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  1. San Juan Montana Thrust Belt WY Thrust Belt Black Warrior

    U.S. Energy Information Administration (EIA) Indexed Site

    San Juan Montana Thrust Belt WY Thrust Belt Black Warrior Paradox - San Juan NW (2) Uinta- Piceance Paradox - San Juan SE (2) Florida Peninsula Appalachian- NY (1) Appalachian ...

  2. San Juan Montana Thrust Belt WY Thrust Belt Black Warrior

    U.S. Energy Information Administration (EIA) Indexed Site

    San Juan Montana Thrust Belt WY Thrust Belt Black Warrior Paradox - San Juan NW (2) Uinta- Piceance Paradox - San Juan SE (2) Florida Peninsula Appalachian- NY (1) Appalachian OH-PA (2) Appalachian Eastern PA (3) Appalachian Southern OH (4) Appalachian Eastern WV (5) Appalachian WV-VA (6) Appalachian TN-KY (7) Piceance Greater Green River Eastern OR-WA Ventura Williston Williston NE (2) Williston NW (1) Williston South (3) Eastern Great Basin Ventura West, Central, East Eastern OR-WA Eastern

  3. Black Warrior, Nevada: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    or Black Warrior Spring coordinates Black Warrior is a property in Washoe County and Churchill County, Nevada that is south and east of Black Warrior Peak. References Nevada...

  4. Cuttings Analysis At Black Warrior Area (DOE GTP) | Open Energy...

    Open Energy Info (EERE)

    Black Warrior Area (DOE GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Cuttings Analysis At Black Warrior Area (DOE GTP) Exploration...

  5. Slim Holes At Black Warrior Area (DOE GTP) | Open Energy Information

    Open Energy Info (EERE)

    Black Warrior Area (DOE GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Slim Holes At Black Warrior Area (DOE GTP) Exploration Activity...

  6. Core Analysis At Black Warrior Area (DOE GTP) | Open Energy Informatio...

    Open Energy Info (EERE)

    Black Warrior Area (DOE GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Core Analysis At Black Warrior Area (DOE GTP) Exploration Activity...

  7. Flow Test At Black Warrior Area (DOE GTP) | Open Energy Information

    Open Energy Info (EERE)

    Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Flow Test At Black Warrior Area (DOE GTP) Exploration Activity Details Location Black Warrior...

  8. File:EIA-BlackWarrior-GAS.pdf | Open Energy Information

    Open Energy Info (EERE)

    applicationpdf) Description Black Warrior Basin By 2001 Gas Reserve Class Sources Energy Information Administration Authors Samuel H. Limerick; Lucy Luo; Gary Long; David F....

  9. Gas Sampling At Black Warrior Area (DOE GTP) | Open Energy Information

    Open Energy Info (EERE)

    GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Gas Sampling At Black Warrior Area (DOE GTP) Exploration Activity Details Location Black...

  10. 2-M Probe At Black Warrior Area (DOE GTP) | Open Energy Information

    Open Energy Info (EERE)

    GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: 2-M Probe At Black Warrior Area (DOE GTP) Exploration Activity Details Location Black...

  11. Gas Flux Sampling At Black Warrior Area (DOE GTP) | Open Energy...

    Open Energy Info (EERE)

    GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Gas Flux Sampling At Black Warrior Area (DOE GTP) Exploration Activity Details Location...

  12. Black Warrior: Sub-soil Gas and Fluid Inclusion Exploration and...

    Open Energy Info (EERE)

    up flow zone drilling targets in a blind geothermal prospect at Black Warrior, Churchill and Washoe Counties, Nevada. Awardees (Company Institution) Nevada Geothermal...

  13. File:Black.Warrior.Basin usgs.map.pdf | Open Energy Information

    Open Energy Info (EERE)

    usgs.map.pdf Jump to: navigation, search File File history File usage Undiscovered Oil and Gas Resources of the Black Warrior Basin Province of Alabama and Mississippi Size...

  14. Reservoir heterogeneity in Carboniferous sandstone of the Black Warrior basin. Final report

    SciTech Connect (OSTI)

    Kugler, R.L.; Pashin, J.C.; Carroll, R.E.; Irvin, G.D.; Moore, H.E.

    1994-04-01

    Although oil production in the Black Warrior basin of Alabama is declining, additional oil may be produced through improved recovery strategies, such as waterflooding, chemical injection, strategic well placement, and infill drilling. High-quality characterization of reservoirs in the Black Warrior basin is necessary to utilize advanced technology to recover additional oil and to avoid premature abandonment of fields. This report documents controls on the distribution and producibility of oil from heterogeneous Carboniferous reservoirs in the Black Warrior basin of Alabama. The first part of the report summarizes the structural and depositional evolution of the Black Warrior basin and establishes the geochemical characteristics of hydrocarbon source rocks and oil in the basin. This second part characterizes facies heterogeneity and petrologic and petrophysical properties of Carter and Millerella sandstone reservoirs. This is followed by a summary of oil production in the Black Warrior basin and an evaluation of seven improved-recovery projects in Alabama. In the final part, controls on the producibility of oil from sandstone reservoirs are discussed in terms of a scale-dependent heterogeneity classification.

  15. Reservoir heterogeneity in carboniferous sandstone of the Black Warrior basin. Final report

    SciTech Connect (OSTI)

    Kugler, R.L.; Pashin, J.C.; Carroll, R.E.; Irvin, G.D.; Moore, H.E.

    1994-06-01

    Although oil production in the Black Warrior basin of Alabama is declining, additional oil may be produced through improved recovery strategies, such as waterflooding, chemical injection, strategic well placement, and infill drilling. High-quality characterization of reservoirs in the Black Warrior basin is necessary to utilize advanced technology to recover additional oil and to avoid premature abandonment of fields. This report documents controls on the distribution and producibility of oil from heterogeneous Carboniferous reservoirs in the Black Warrior basin of Alabama. The first part of the report summarizes the structural and depositional evolution of the Black Warrior basin and establishes the geochemical characteristics of hydrocarbon source rocks and oil in the basin. This second part characterizes facies heterogeneity and petrologic and petrophysical properties of Carter and Millerella sandstone reservoirs. This is followed by a summary of oil production in the Black Warrior basin and an evaluation of seven improved-recovery projects in Alabama. In the final part, controls on the producibility of oil from sandstone reservoirs are discussed in terms of a scale-dependent heterogeneity classification.

  16. Coal stratigraphy of deeper part of Black Warrior basin in Alabama

    SciTech Connect (OSTI)

    Thomas, W.A.; Womack, S.H.

    1983-09-01

    The Warrior coal field of Alabama is stratigraphically in the upper part of the Lower Pennsylvanian Pottsville Formation and structurally in the eastern part of the Black Warrior foreland basin. The productive coal beds extend southwestward from the mining area downdip into the deeper part of the Black Warrior structural basin. Because the deep part of the basin is beyond the limits of conventional coal exploration, study of the stratigraphy of coal beds must rely on data from petroleum wells. Relative abundance of coal can be stated in terms of numbers of beds, but because of the limitations of the available data, thicknesses of coals presently are not accurately determined. The lower sandstone-rich coal-poor part of the Pottsville has been interpreted as barrier sediments in the mining area. To the southwest in the deeper Black Warrior basin, coal beds are more numerous within the sandstone-dominated sequence. The coal-productive upper Pottsville is informally divided into coal groups each of which includes several coal beds. The Black Creek, Mary Lee, and Utley coal groups are associated with northeast-trending delta-distributary sandstones. The areas of most numerous coals also trend northeastward and are laterally adjacent to relatively thick distributary sandstones, suggesting coal accumulation in backswamp environments. The most numerous coals in the Pratt coal group are in an area that trends northwestward parallel with and southwest of a northwest-trending linear sandstone, suggesting coal accumulation in a back-barrier environment. Equivalents of the Cobb, Gwin, and Brookwood coal groups contain little coal in the deep part of the Black Warrior basin.

  17. Feasibility study of heavy oil recovery in the Appalachian, Black Warrior, Illinois, and Michigan basins

    SciTech Connect (OSTI)

    Olsen, D.K.; Rawn-Schatzinger, V.; Ramzel, E.B.

    1992-07-01

    This report is one of a series of publications assessing the feasibility of increasing domestic heavy oil production. Each report covers select areas of the United States. The Appalachian, Black Warrior, Illinois, and Michigan basins cover most of the depositional basins in the Midwest and Eastern United States. These basins produce sweet, paraffinic light oil and are considered minor heavy oil (10{degrees} to 20{degrees} API gravity or 100 to 100,000 cP viscosity) producers. Heavy oil occurs in both carbonate and sandstone reservoirs of Paleozoic Age along the perimeters of the basins in the same sediments where light oil occurs. The oil is heavy because escape of light ends, water washing of the oil, and biodegradation of the oil have occurred over million of years. The Appalachian, Black Warrior, Illinois, and Michigan basins` heavy oil fields have produced some 450,000 bbl of heavy oil of an estimated 14,000,000 bbl originally in place. The basins have been long-term, major light-oil-producing areas and are served by an extensive pipeline network connected to refineries designed to process light sweet and with few exceptions limited volumes of sour or heavy crude oils. Since the light oil is principally paraffinic, it commands a higher price than the asphaltic heavy crude oils of California. The heavy oil that is refined in the Midwest and Eastern US is imported and refined at select refineries. Imports of crude of all grades accounts for 37 to >95% of the oil refined in these areas. Because of the nature of the resource, the Appalachian, Black Warrior, Illinois and Michigan basins are not expected to become major heavy oil producing areas. The crude oil collection system will continue to degrade as light oil production declines. The demand for crude oil will increase pipeline and tanker transport of imported crude to select large refineries to meet the areas` liquid fuels needs.

  18. Feasibility study of heavy oil recovery in the Appalachian, Black Warrior, Illinois, and Michigan basins

    SciTech Connect (OSTI)

    Olsen, D.K.; Rawn-Schatzinger, V.; Ramzel, E.B.

    1992-07-01

    This report is one of a series of publications assessing the feasibility of increasing domestic heavy oil production. Each report covers select areas of the United States. The Appalachian, Black Warrior, Illinois, and Michigan basins cover most of the depositional basins in the Midwest and Eastern United States. These basins produce sweet, paraffinic light oil and are considered minor heavy oil (10{degrees} to 20{degrees} API gravity or 100 to 100,000 cP viscosity) producers. Heavy oil occurs in both carbonate and sandstone reservoirs of Paleozoic Age along the perimeters of the basins in the same sediments where light oil occurs. The oil is heavy because escape of light ends, water washing of the oil, and biodegradation of the oil have occurred over million of years. The Appalachian, Black Warrior, Illinois, and Michigan basins' heavy oil fields have produced some 450,000 bbl of heavy oil of an estimated 14,000,000 bbl originally in place. The basins have been long-term, major light-oil-producing areas and are served by an extensive pipeline network connected to refineries designed to process light sweet and with few exceptions limited volumes of sour or heavy crude oils. Since the light oil is principally paraffinic, it commands a higher price than the asphaltic heavy crude oils of California. The heavy oil that is refined in the Midwest and Eastern US is imported and refined at select refineries. Imports of crude of all grades accounts for 37 to >95% of the oil refined in these areas. Because of the nature of the resource, the Appalachian, Black Warrior, Illinois and Michigan basins are not expected to become major heavy oil producing areas. The crude oil collection system will continue to degrade as light oil production declines. The demand for crude oil will increase pipeline and tanker transport of imported crude to select large refineries to meet the areas' liquid fuels needs.

  19. GEOLOGIC SCREENING CRITERIA FOR SEQUESTRATION OF CO2 IN COAL: QUANTIFYING POTENTIAL OF THE BLACK WARRIOR COALBED METHANE FAIRWAY, ALABAMA

    SciTech Connect (OSTI)

    Jack C. Pashin; Richard E. Carroll; Richard H. Groshong Jr.; Dorothy E. Raymond; Marcella McIntyre; J. Wayne Payton

    2004-01-01

    Sequestration of CO{sub 2} in coal has potential benefits for reducing greenhouse gas emissions from the highly industrialized Carboniferous coal basins of North America and Europe and for enhancing coalbed methane recovery. Hence, enhanced coalbed methane recovery operations provide a basis for a market-based environmental solution in which the cost of sequestration is offset by the production and sale of natural gas. The Black Warrior foreland basin of west-central Alabama contains the only mature coalbed methane production fairway in eastern North America, and data from this basin provide an excellent basis for quantifying the carbon sequestration potential of coal and for identifying the geologic screening criteria required to select sites for the demonstration and commercialization of carbon sequestration technology. Coalbed methane reservoirs in the upper Pottsville Formation of the Black Warrior basin are extremely heterogeneous, and this heterogeneity must be considered to screen areas for the application of CO{sub 2} sequestration and enhanced coalbed methane recovery technology. Major screening factors include stratigraphy, geologic structure, geothermics, hydrogeology, coal quality, sorption capacity, technology, and infrastructure. Applying the screening model to the Black Warrior basin indicates that geologic structure, water chemistry, and the distribution of coal mines and reserves are the principal determinants of where CO{sub 2} can be sequestered. By comparison, coal thickness, temperature-pressure conditions, and coal quality are the key determinants of sequestration capacity and unswept coalbed methane resources. Results of this investigation indicate that the potential for CO{sub 2} sequestration and enhanced coalbed methane recovery in the Black Warrior basin is substantial and can result in significant reduction of greenhouse gas emissions while increasing natural gas reserves. Coal-fired power plants serving the Black Warrior basin in

  20. Geohydrological feasibility study of the Black Warrior Basin for the potential applicability of Jack W. McIntyre`s patented process

    SciTech Connect (OSTI)

    Reed, P.D.

    1994-03-01

    Geraghty & Miller, Inc. of Midland, Texas conducted geological and hydrological feasibility studies of the potential applicability of Jack W. Mclntyre`s patented process for the recovery of natural gas from coalbed/sand formations in the Black Warrior Basin of Mississippi and Alabama through literature surveys. Methane gas from coalbeds in the Black Warrior Basin is confined to the coal fields of northern Alabama. Produced water from degasification of coalbeds is currently disposed by surface discharge. Treatment prior to discharge consists of short-term storage and in-stream dilution. Mr. Mclntyre`s process appears to be applicable to the Black Warrior Basin and could provide an environmentally sound alternative for produced water production.

  1. Water Management Strategies for Improved Coalbed Methane Production in the Black Warrior Basin

    SciTech Connect (OSTI)

    Pashin, Jack; McIntyre-Redden, Marcella; Mann, Steven; Merkel, David

    2013-10-31

    The modern coalbed methane industry was born in the Black Warrior Basin of Alabama and has to date produced more than 2.6 trillion cubic feet of gas and 1.6 billion barrels of water. The coalbed gas industry in this area is dependent on instream disposal of co-produced water, which ranges from nearly potable sodium-bicarbonate water to hypersaline sodium-chloride water. This study employed diverse analytical methods to characterize water chemistry in light of the regional geologic framework and to evaluate the full range of water management options for the Black Warrior coalbed methane industry. Results reveal strong interrelationships among regional geology, water chemistry, and gas chemistry. Coalbed methane is produced from multiple coal seams in Pennsylvanian-age strata of the Pottsville Coal Interval, in which water chemistry is influenced by a structurally controlled meteoric recharge area along the southeastern margin of the basin. The most important constituents of concern in the produced water include chlorides, ammonia compounds, and organic substances. Regional mapping and statistical analysis indicate that the concentrations of most ionic compounds, metallic substances, and nonmetallic substances correlate with total dissolved solids and chlorides. Gas is effectively produced at pipeline quality, and the only significant impurity is N{sub 2}. Geochemical analysis indicates that the gas is of mixed thermogenic-biogenic origin. Stable isotopic analysis of produced gas and calcite vein fills indicates that widespread late-stage microbial methanogenesis occurred primarily along a CO{sub 2} reduction metabolic pathway. Organic compounds in the produced water appear to have helped sustain microbial communities. Ammonia and ammonium levels increase with total dissolved solids content and appear to have played a role in late-stage microbial methanogenesis and the generation of N{sub 2}. Gas production tends to decline exponentially, whereas water production

  2. Secondary oil recovery from selected Carter sandstone oilfields, Black Warrior basin, Alabama. [Annual] yearly report, December 1, 1992--November 30, 1993

    SciTech Connect (OSTI)

    Anderson, J.C.

    1994-03-01

    In this Class I PON, Anderman/Smith Operating Company is targeting three Carter sandstone oilfields (Black Warrior basin) for secondary recovery. Waterfloods are underway in two of the areas -- Central Bluff and North Fairview units. For the third area, South Bluff, negotiations are underway to unitize the field. Once South Bluff is unitized, waterflooding will commence.

  3. GEOLOGIC SCREENING CRITERIA FOR SEQUESTRATION OF CO2 IN COAL: QUANTIFYING POTENTIAL OF THE BLACK WARRIOR COALBED METHANE FAIRWAY, ALABAMA

    SciTech Connect (OSTI)

    Jack C. Pashin; Richard E. Carroll; Richard H. Groshong, Jr.; Dorothy E. Raymond; Marcella McIntyre; J. Wayne Payton

    2003-01-01

    Sequestration of CO{sub 2} in coal has potential to reduce greenhouse gas emissions from coal-fired power plants while enhancing coalbed methane recovery. Data from more than 4,000 coalbed methane wells in the Black Warrior basin of Alabama provide an opportunity to quantify the carbon sequestration potential of coal and to develop a geologic screening model for the application of carbon sequestration technology. This report summarizes stratigraphy and sedimentation, structural geology, geothermics, hydrology, coal quality, gas capacity, and production characteristics of coal in the Black Warrior coalbed methane fairway and the implications of geology for carbon sequestration and enhanced coalbed methane recovery. Coal in the Black Warrior basin is distributed among several fluvial-deltaic coal zones in the Lower Pennsylvanian Pottsville Formation. Most coal zones contain one to three coal beds that are significant targets for coalbed methane production and carbon sequestration, and net coal thickness generally increases southeastward. Pottsville strata have effectively no matrix permeability to water, so virtually all flow is through natural fractures. Faults and folds influence the abundance and openness of fractures and, hence, the performance of coalbed methane wells. Water chemistry in the Pottsville Formation ranges from fresh to saline, and zones with TDS content lower than 10,000 mg/L can be classified as USDW. An aquifer exemption facilitating enhanced recovery in USDW can be obtained where TDS content is higher than 3,000 mg/L. Carbon dioxide becomes a supercritical fluid above a temperature of 88 F and a pressure of 1,074 psi. Reservoir temperature exceeds 88 F in much of the study area. Hydrostatic pressure gradients range from normal to extremely underpressured. A large area of underpressure is developed around closely spaced longwall coal mines, and areas of natural underpressure are distributed among the coalbed methane fields. The mobility and

  4. Site Characterization for CO{sub 2} Storage from Coal-fired Power Facilities in the Black Warrior Basin of Alabama

    SciTech Connect (OSTI)

    Clark, Peter; Pashin, Jack; Carlson, Eric; Goodliffe, Andrew; McIntyre-Redden, Marcella; Mann, Steven; Thompson, Mason

    2012-08-31

    Coal-fired power plants produce large quantities of carbon dioxide. In order to mitigate the greenhouse gas emissions from these power plants, it is necessary to separate and store the carbon dioxide. Saline formations provide a potential sink for carbon dioxide and delineating the capacity of the various known saline formations is a key part of building a storage inventory. As part of this effort, a project was undertaken to access the storage capacity of saline reservoirs in the Black Warrior Basin of Alabama. This basin has been a productive oil and gas reservoir that is well characterized to the west of the two major coal-fired power plants that are north of Birmingham. The saline zones were thought to extend as far east as the Sequatchie Anticline which is just east of the power plants. There is no oil or gas production in the area surrounding the power plants so little is known about the formations in that area. A geologic characterization well was drilled on the Gorgas Power Plant site, which is the farthest west of two power plants in the area. The well was planned to be drilled to approximately 8,000 feet, but drilling was halted at approximately 5,000 feet when a prolific freshwater zone was penetrated. During drilling, a complete set of cores through all of the potential injection zones and the seals above these zones were acquired. A complete set of openhole logs were run along with a vertical seismic profile (VSP). Before drilling started two approximately perpendicular seismic lines were run and later correlated with the VSP. While the zones that were expected were found at approximately the predicted depths, the zones that are typically saline through the reservoir were found to be saturated with a light crude oil. Unfortunately, both the porosity and permeability of these zones were small enough that no meaningful hydrocarbon production would be expected even with carbon dioxide flooding. iv While this part of the basin was found to be unsuitable

  5. Sandia National Laboratories: Cold War Warriors

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Cold War Warriors By Sue Major Holmes Thursday, April 28, 2016 The story of Sandia's decades in nuclear field testing Sandia videographer and documentarian Myra Buteau has produced ...

  6. Black Warrior Geothermal Area | Open Energy Information

    Open Energy Info (EERE)

    135C408.15 K 275 F 734.67 R 1 USGS Estimated Reservoir Volume: 2 km 1 USGS Mean Capacity: 17 MW 1 Click "Edit With Form" above to add content History and...

  7. Ancient Warriors and the Origin of Chinese Purple

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Ancient Warriors and the Origin of Chinese Purple Figure 1: (a) Warrior # T18G21-08, a kneeling archer. The pigment samples in this study have been taken from this terracotta warrior. (b) Close-up picture of the purple paint on the terracotta warrior. (c) Images of the purple paint samples used in this study. In March 1974 during the sinking of wells for farmland irrigation near Xi'an, China, nine farmers made one of the world's most remarkable archaeological finds: the discovery of an army

  8. File:EIA-BlackWarrior-LIQ.pdf | Open Energy Information

    Open Energy Info (EERE)

    Samuel H. Limerick; Lucy Luo; Gary Long; David F. Morehouse; Jack Perrin; Robert F. King Related Technologies Oil, Natural Gas Creation Date 2005-09-01 Extent Regional...

  9. File:EIA-BlackWarrior-BOE.pdf | Open Energy Information

    Open Energy Info (EERE)

    Samuel H. Limerick; Lucy Luo; Gary Long; David F. Morehouse; Jack Perrin; Robert F. King Related Technologies Oil, Natural Gas Creation Date 2005-09-01 Extent Regional...

  10. Laterally bendable belt conveyor

    DOE Patents [OSTI]

    Peterson, William J.

    1985-01-01

    An endless, laterally flexible and bendable belt conveyor particularly adapted for coal mining applications in facilitating the transport of the extracted coal up- or downslope and around corners in a continuous manner is disclosed. The conveying means includes a flat rubber belt reinforced along the middle portion thereof along which the major portion of the belt tension is directed so as to cause rotation of the tubular shaped belt when trammed around lateral turns thus preventing excessive belt bulging distortion between adjacent belt supports which would inhibit belt transport. Pretension induced into the fabric reinforced flat rubber belt by conventional belt take-up means supports the load conveyed when the belt conveyor is making lateral turns. The carrying and return portions of the belt are supported and formed into a tubular shape by a plurality of shapers positioned along its length. Each shaper is supported from above by a monorail and includes clusters of idler rollers which support the belt. Additional cluster rollers in each shaper permit the belt supporting roller clusters to rotate in response to the belt's operating tension imposed upon the cluster rollers by induced lateral belt friction forces. The freely rotating roller clusters thus permit the belt to twist on lateral curves without damage to itself while precluding escape of the conveyed material by effectively enclosing it in the tube-shaped, inner belt transport length.

  11. Belt attachment and system

    DOE Patents [OSTI]

    Schneider, Abraham D.; Davidson, Erick M.

    2016-02-02

    Disclosed herein is a belt assembly including a flexible belt with an improved belt attachment. The belt attachment includes two crossbars spaced along the length of the belt. The crossbars retain bearings that allow predetermined movement in six degrees of freedom. The crossbars are connected by a rigid body that attaches to the bearings. Implements that are attached to the rigid body are simply supported but restrained in pitching rotation.

  12. Replace V-Belts with Notched or Synchronous Belt Drives

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    ... However, synchronous belts are noisier than V-belts, less suited for use on shock-loaded ... However, notched belts may be a better choice when vibration damping is needed or shock ...

  13. Black Warrior: Sub-soil gas and fluid inclusion exploration and...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    and isotope data to define possible upflow areas; Calibrate the sub-soil chemistry with down-hole fluid inclusion stratigraphy and fluid analyses to define a follow-up ...

  14. Black Warrior: Sub-soil gas and fluid inclusion exploration and slim well drilling

    Broader source: Energy.gov [DOE]

    DOE Geothermal Peer Review 2010 - Presentation. Project Objectives: Discover a blind, low-moderate temperature resource: Apply a combination of detailed sub-soil gas, hydrocarbon, and isotope data to define possible upflow areas; Calibrate the sub-soil chemistry with down-hole fluid inclusion stratigraphy and fluid analyses to define a follow-up exploration drilling target; Create short term jobs and long term employment through resource exploration, development and power plant operation; Extend and adapt the DOE sub-soil 2 meter probe technology to gas sampling.

  15. Secondary oil recovery from selected Carter sandstone oilfields--Black Warrior Basin, Alabama. Final report

    SciTech Connect (OSTI)

    Anderson, J.C.

    1995-02-01

    Producibility problems, such as low reservoir pressure and reservoir heterogeneity, have severely limited oil production from the Central Bluff and North Fairview fields. Specific objectives for this project were: To successfully apply detailed geologic and engineering studies with conventional waterflood technologies to these fields in an effort to increase the ultimate economic recovery of oil from Carter sandstone fields; To extensively model, test and evaluate these technologies; thereby, developing a sound methodology for their use and optimization; and To team with Advanced Resources International and the US DOE to assimilate and transfer the information and results gathered from this study to other oil companies to encourage the widespread use of these technologies. At Central Bluff, water injection facilities were constructed and water injection into one well began in January 1993. Oil response from the waterflood has been observed at both producing wells. One of the producing wells has experienced early water breakthrough and a concomitant drop in secondary oil rate. A reservoir modeling study was initiated to help develop an appropriate operating strategy for Central Bluff. For the North Fairview unit waterflood, a previously abandoned well was converted for water injection which began in late June 1993. The reservoir is being re-pressurized, and unit water production has remained nil since flood start indicating the possible formation of an oil bank. A reservoir simulation to characterize the Carter sand at North Fairview was undertaken and the modeling results were used to forecast field performance. The project was terminated due to unfavorable economics. The factors contributing to this decision were premature water breakthrough at Central Bluff, delayed flood response at North Fairview and stalled negotiations at the South Bluff site.

  16. SLH Timing Belt Powertrain

    SciTech Connect (OSTI)

    Schneider, Abe

    2014-04-09

    The main goal of this proposal was to develop and test a novel powertrain solution for the SLH hydroEngine, a low-cost, efficient low-head hydropower technology. Nearly two-thirds of U.S. renewable electricity is produced by hydropower (EIA 2010). According to the U.S. Department of Energy; this amount could be increased by 50% with small hydropower plants, often using already-existing dams (Hall 2004). There are more than 80,000 existing dams, and of these, less than 4% generate power (Blankinship 2009). In addition, there are over 800 irrigation districts in the U.S., many with multiple, non-power, low-head drops. These existing, non-power dams and irrigation drops could be retrofitted to produce distributed, baseload, renewable energy with appropriate technology. The problem is that most existing dams are low-head, or less than 30 feet in height (Ragon 2009). Only about 2% of the available low-head hydropower resource in the U.S. has been developed, leaving more than 70 GW of annual mean potential low-head capacity untapped (Hall 2004). Natel Energy, Inc. is developing a low-head hydropower turbine that operates efficiently at heads less than 6 meters and is cost-effective for deployment across multiple low-head structures. Because of the unique racetrack-like path taken by the prime-movers in the SLH, a flexible powertrain is required. Historically, the only viable technological solution was roller chain. Despite the having the ability to easily attach blades, roller chain is characterized by significant drawbacks, including high cost, wear, and vibration from chordal action. Advanced carbon- fiber-reinforced timing belts have been recently developed which, coupled with a novel belt attachment system developed by Natel Energy, result in a large reduction in moving parts, reduced mass and cost, and elimination of chordal action for increased fatigue life. The work done in this project affirmatively addressed each of the following 3 major uncertainties concerning

  17. SunBelt Biofuels | Open Energy Information

    Open Energy Info (EERE)

    SunBelt Biofuels Jump to: navigation, search Logo: SunBelt Biofuels Name: SunBelt Biofuels Place: Soperton, Georgia Zip: 30457 Sector: Biomass Product: Freedom Giant Miscanthus...

  18. Compliance Monitoring of Underwater Blasting for Rock Removal at Warrior Point, Columbia River Channel Improvement Project, 2009/2010

    SciTech Connect (OSTI)

    Carlson, Thomas J.; Johnson, Gary E.; Woodley, Christa M.; Skalski, J. R.; Seaburg, Adam

    2011-05-10

    The U.S. Army Corps of Engineers, Portland District (USACE) conducted the 20-year Columbia River Channel Improvement Project (CRCIP) to deepen the navigation channel between Portland, Oregon, and the Pacific Ocean to allow transit of fully loaded Panamax ships (100 ft wide, 600 to 700 ft long, and draft 45 to 50 ft). In the vicinity of Warrior Point, between river miles (RM) 87 and 88 near St. Helens, Oregon, the USACE conducted underwater blasting and dredging to remove 300,000 yd3 of a basalt rock formation to reach a depth of 44 ft in the Columbia River navigation channel. The purpose of this report is to document methods and results of the compliance monitoring study for the blasting project at Warrior Point in the Columbia River.

  19. Replace V-Belts with Notched or Synchronous Belt Drives | Department of

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Energy V-Belts with Notched or Synchronous Belt Drives Replace V-Belts with Notched or Synchronous Belt Drives Belt drives provide flexibility in the positioning of the motor relative to the load. Pulleys (sheaves) of varying diameters allow the speed of the driven equipment to be increased or decreased relative to the motor speed. A properly designed belt power-transmission system offers high efficiency and low noise, requires no lubrication, and presents low maintenance requirements.

  20. Upgrading Orinoco belt heavy oil

    SciTech Connect (OSTI)

    Alcantara, J.; Castillo, O.

    1982-09-01

    The Orinoco Heavy Oil Belt of Venezuela is a subsurface geological formation of petroleum-bearing sands that is approximately 700 km long and between 60 and 80 km wide. The results of recent explorations have shown the area to contain over one trillion barrels of oil in-place, ranging from 8/sup 0/ API to 14/sup 0/ APE gravity. In an effort to develop these resources, Petroleos de Venezuela has undertaken a program to evaluate and develop this heavy oil belt. The objectives of this program are discussed along with the process technology selection, pilot plants, and environmental protection measures. (JMT)

  1. Upgrading Orinoco Belt heavy oil

    SciTech Connect (OSTI)

    Aliantara, J.; Castillo, O.

    1982-05-01

    Petroleos de Venezuela, S.A. (PDVSA), in an effort to develop new oil resources, has undertaken a program to evaluate and develop the Orinoco Heavy Oil Belt, in the eastern part of Venezuela. Lagoven, S.A., a subsidiary of PDVSA, has been assigned the responsibility for developing and upgrading part of the Orinoco belt. This paper describes the most relevant aspects of Lagoven's first upgrading module, a facility that will convert Orinoco oil into a premium crude with a very high yield of products of great market demand.

  2. Synchronous and Cogged Fan Belt Performance Assessment

    SciTech Connect (OSTI)

    Cutler, D.; Dean, J.; Acosta, J.

    2014-02-01

    The GSA Regional GPG Team commissioned the National Renewable Energy Laboratory (NREL) to perform monitoring of cogged V-belts and synchronous belts on both a constant volume and a variable air volume fan at the Byron G. Rodgers Federal Building and U.S. Courthouse in Denver, Colorado. These motor/fan combinations were tested with their original, standard V-belts (appropriately tensioned by an operation and maintenance professional) to obtain a baseline for standard operation. They were then switched to the cogged V-belts, and finally to synchronous belts. The power consumption by the motor was normalized for both fan speed and air density changes. This was necessary to ensure that the power readings were not influenced by a change in rotational fan speed or by the power required to push denser air. Finally, energy savings and operation and maintenance savings were compiled into an economic life-cycle cost analysis of the different belt options.

  3. CD-2: Orogenic Belt | Open Energy Information

    Open Energy Info (EERE)

    basin or orogenic mountain belt. Significant crustal subsidence (up to several kilometers) occurs in sedimentary sequences. This subsidence is due to the weight of the...

  4. Corn Belt Power Cooperative Rebate Program

    Broader source: Energy.gov [DOE]

    Corn Belt Power Cooperative is a generation and transmission electric cooperative that provides power to nine distribution rural electric cooperatives and one municipal electric cooperative. These...

  5. Belt Vision Inspection System | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    in mining conveyance systems. Provides a user interface for belt inspection at installation points using software that controls the cameras, collects encoder data, and ...

  6. Study finds surprising variability in shape of Van Allen Belts

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Study finds surprising variability in shape of Van Allen Belts Study finds surprising variability in shape of Van Allen Belts Understanding the shape and size of the belts, which shrink and swell in response to magnetic storms coming from the sun, is crucial for protecting our technology in space. February 23, 2016 1. The traditional idea of the radiation belts includes a larger, more dynamic outer belt and a smaller, more stable inner belt with an empty slot region separating the two. However,

  7. Radiation Belts and Ring Current The Energetic Geospace (Conference...

    Office of Scientific and Technical Information (OSTI)

    Conference: Radiation Belts and Ring Current The Energetic Geospace Citation Details In-Document Search Title: Radiation Belts and Ring Current The Energetic Geospace Authors: Reeves, ...

  8. Radiation Belts and Ring Current The Energetic Geospace (Conference...

    Office of Scientific and Technical Information (OSTI)

    Radiation Belts and Ring Current The Energetic Geospace Citation Details In-Document Search Title: Radiation Belts and Ring Current The Energetic Geospace You are accessing a ...

  9. Electric filter with movable belt electrode

    DOE Patents [OSTI]

    Bergman, W.

    1983-09-20

    A method and apparatus for removing airborne contaminants entrained in a gas or airstream includes an electric filter characterized by a movable endless belt electrode, a grounded electrode, and a filter medium sandwiched there between. Inclusion of the movable, endless belt electrode provides the driving force for advancing the filter medium through the filter, and reduces frictional drag on the filter medium, thereby permitting a wide choice of filter medium materials. Additionally, the belt electrode includes a plurality of pleats in order to provide maximum surface area on which to collect airborne contaminants. 4 figs.

  10. Electric filter with movable belt electrode

    DOE Patents [OSTI]

    Bergman, Werner

    1983-01-01

    A method and apparatus for removing airborne contaminants entrained in a gas or airstream includes an electric filter characterized by a movable endless belt electrode, a grounded electrode, and a filter medium sandwiched therebetween. Inclusion of the movable, endless belt electrode provides the driving force for advancing the filter medium through the filter, and reduces frictional drag on the filter medium, thereby permitting a wide choice of filter medium materials. Additionally, the belt electrode includes a plurality of pleats in order to provide maximum surface area on which to collect airborne contaminants.

  11. Congressional panel makes recommendations on belt safety

    SciTech Connect (OSTI)

    Fiscor, S.

    2007-12-15

    The Mine Improvement and New Emergency Response Act of 2006 (MINER Act) called for a Technical Study Panel to present a review and make recommendations on the use of belt air and the composition and fire retardant properties of belt materials in underground coal mining. In October 2007 the Panel released 20 recommendations publicly. These are presented in the article. Many recommendations encouraged the MSHA to enforce existing laws of maintenance and fire protection or example more vigorously. Maybe the biggest change recommended was that the industry should adopt the Belt Evaluation Laboratory Test (BELT) standard proposed in 1992. Another important recommendation was one that would help eliminate hazards associated with point feeding. 1 photo.

  12. A new picture of the Van Allen Belts

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    A new picture of the Van Allen Belts A new picture of the Van Allen Belts A study conducted by Los Alamos and the New Mexico Consortium reveals that the shape of the Van Allen Belts is actually quite different than previously believed. January 21, 2016 van allen belts During geomagnetic storms, the empty region between the two belts can fill in completely with lower-energy electrons. Traditionally, scientists thought this slot region filled in only during the most extreme geomagnetic storms

  13. Picture of the Week: Bulging Van Allen Belts

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2 Bulging Van Allen Belts Learn about the Van Allen Belts and how new findings from NASA's Van Allen Probes could impact how we protect technology in space. February 25, 2016 Bulging Van Allen Belts Watch the video on YouTube. Bulging Van Allen Belts Learn about the Van Allen Belts and how new findings from NASA's Van Allen Probes could impact how we protect technology in space

  14. Los Alamos provides HOPE for radiation belt storm probes

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    HOPE for radiation belt storm probes Los Alamos provides HOPE for radiation belt storm probes The HOPE analyzer is one of a suite of instruments that was successfully launched as part of the Radiation Belt Storm Probe mission. August 30, 2012 Artist's rendering showing two spacecraft representing the not-yet-designed Radiation Belt Storm Probes that will study the sun and its effects on Earth. PHOTO CREDIT: Johns Hopkins University Applied Physics Laboratory Artist's rendering showing two

  15. New compounds will help coal operators comply with BELT standards

    SciTech Connect (OSTI)

    2009-04-15

    US coal producers will soon have a new set of conveyor belting standards, which are currently proposed as a rulemaking by the Mine Safety and Health Administration (MSHA), to bring higher levels of resistance to propagation of fire by a secondary source. The new test being put into effect is known as a Belt Evaluation Laboratory Test (BELT). The article, submitted by Fenner Dunlop, discusses the company's testing procedures and the development of conveyors to comply with regulations. 2 photos.

  16. Magnetic refrigeration apparatus with belt of ferro or paramagnetic material

    DOE Patents [OSTI]

    Barclay, J.A.; Stewart, W.F.; Henke, M.D.; Kalash, K.E.

    1986-04-03

    A magnetic refrigerator operating in the 12 to 77 K range utilizes a belt which carries ferromagnetic or paramagnetic material and which is disposed in a loop which passes through the center of a solenoidal magnet to achieve cooling. The magnetic material carried by the belt, which can be blocks in frames of a linked belt, can be a mixture of substances with different Curie temperatures arranged such that the Curie temperatures progressively increase from one edge of the belt to the other. This magnetic refrigerator can be used to cool and liquefy hydrogen or other fluids.

  17. Magnetic refrigeration apparatus with belt of ferro or paramagnetic material

    DOE Patents [OSTI]

    Barclay, John A.; Stewart, Walter F.; Henke, Michael D.; Kalash, Kenneth E.

    1987-01-01

    A magnetic refrigerator operating in the 12 to 77K range utilizes a belt which carries ferromagnetic or paramagnetic material and which is disposed in a loop which passes through the center of a solenoidal magnet to achieve cooling. The magnetic material carried by the belt, which can be blocks in frames of a linked belt, can be a mixture of substances with different Curie temperatures arranged such that the Curie temperatures progressively increase from one edge of the belt to the other. This magnetic refrigerator can be used to cool and liquefy hydrogen or other fluids.

  18. Black Pine Engineering

    Broader source: Energy.gov [DOE]

    Black Pine Engineering is commercializing a disruptive technology in the turbomachinery industry. Using a patented woven composite construction, Black Pine Engineering can make turbomachines (turbines, compressors) that are cheaper and lighter than competing technologies. Using this technology, Black Pine Engineering will sell turbo-compressors which solve the problem of wasted steam in geothermal power plants.

  19. Mysterious electron stash found hidden among Van Allen belts

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    have confirmed a never-before-seen phenomenon-a long-lived zone of high-energy electrons residing between the inner and outer radiation belts. (Credit: NASA illustration)...

  20. Carbon smackdown: wind warriors

    ScienceCinema (OSTI)

    Glen Dahlbacka of the Accelerator & Fusion Research Division and Ryan Wiser of the Environmental Energy Technologies Division are the speakers.

    2010-09-01

    July 16. 2010 carbon smackdown summer lecture: learn how Berkeley Lab scientists are developing wind turbines to be used in an urban setting, as well as analyzing what it will take to increase the adoption of wind energy in the U.S.

  1. BLACK HISTORY MONTH

    Broader source: Energy.gov [DOE]

    Black History Month is an annual celebration of achievements by black Americans and a time for recognizing the central role of African Americans in U.S. history. The event grew out of “Negro History Week,” created by historian Carter G. Woodson and other prominent African Americans. Other countries around the world, including Canada and the United Kingdom, also devote a month to celebrating black history.

  2. Angle stations in or for endless conveyor belts

    DOE Patents [OSTI]

    Steel, Alan

    1987-04-07

    In an angle station for an endless conveyor belt, there are presented to each incoming run of the belt stationary curved guide members (18, 19) of the shape of a major segment of a right-circular cylinder and having in the part-cylindrical portion (16 or 17) thereof rectangular openings (15) arranged in parallel and helical paths and through which project small freely-rotatable rollers (14), the continuously-changing segments of the curved surfaces of which projecting through said openings (15) are in attitude to change the direction of travel of the belt (13) through 90.degree. during passage of the belt about the part-cylindrical portion (16 or 17) of the guide member (18 or 19). The rectangular openings (15) are arranged with their longer edges lengthwise of the diagonals representing the mean of the helix but with those of a plurality of the rows nearest to each end of the part-cylindrical portion (16 or 17) slightly out of axial symmetry with said diagonals, being slightly inclined in a direction about the intersections (40) of the diagonals of the main portion of the openings, to provide a "toe-in" attitude in relation to the line of run of the endless conveyor belt.

  3. Early Proterozoic transcontinental orogenic belts in the United States

    SciTech Connect (OSTI)

    Van Schmus, W.R. . Dept. of Geology); Bickford, M.E. . Dept. of Geology); Condie, K.C. . Dept. Geoscience)

    1993-02-01

    It has been recognized for many years that Early Proterozoic orogenic rocks in the western US range from 1.8 to 1.6 Ga, with a general distribution such that 1.8 to 1.7 Ga rocks underlie Colorado, northern Arizona, and northern New Mexico and 1.7 to 1.6 Ga rocks underlie southern Arizona and southern New Mexico. Recent U-Pb geochronologic and Sm-Nd isotopic studies by a variety of research groups have refined crustal history in the western region and have extended knowledge eastward into the buried midcontinent basement. As a result, the authors propose that 1.8 Ga to 1.6 Ga crust of the US by divided into two distinct, but overlapping, orogenic belts: a 1.8 to 1.7 Ga Inner Accretionary Belt and a 1.7 to 1.6 Ga Outer Tectonic Belt. The Inner Accretionary Belt (IAB) comprises rock suites with compositions and isotopic signatures compatible with origin as juvenile crustal terranes formed as oceanic or off-shore and related terranes that were accreted to southern Laurentia between 1.8 and 1.6 Ga. The IAB includes the Yavapai Province of Arizona, Early Proterozoic basement of Colorado and southern Wyoming, and the basement of Nebraska. The Mojave Province of California may be part of this belt, although it also includes components derived from older Proterozoic or Archean crust. Extension of the IAB eastward from Nebraska is uncertain at present, although coeval rocks that may be eastern manifestations of this 1.8 to 1.7 Ga orogenesis occur in Wisconsin (1.76 Ga granite-rhyolite suite), Ontario (Killarney granite), Labrador (Makkovic Province) and southern Greenland (Ketilidian orogen). The Outer Tectonic Belt (OTB) comprises rock suites which have compositions, structures, and isotopic signature compatible with origin in continental margin tectonic settings between 1.7 and 1.6 Ga.

  4. Dotiki saves money and time with power tool and belt fasteners

    SciTech Connect (OSTI)

    Bargo, K.

    2009-11-15

    The use of a Hilti power tool to improve belt splice installations to minimise downtime is described. 3 photos.

  5. ULTRAMASSIVE BLACK HOLE COALESCENCE

    SciTech Connect (OSTI)

    Khan, Fazeel Mahmood; Holley-Bockelmann, Kelly; Berczik, Peter E-mail: k.holley@vanderbilt.edu

    2015-01-10

    Although supermassive black holes (SMBHs) correlate well with their host galaxies, there is an emerging view that outliers exist. Henize 2-10, NGC4889, and NGC1277 are examples of SMBHs at least an order of magnitude more massive than their host galaxy suggests. The dynamical effects of such ultramassive central black holes is unclear. Here, we perform direct N-body simulations of mergers of galactic nuclei where one black hole is ultramassive to study the evolution of the remnant and the black hole dynamics in this extreme regime. We find that the merger remnant is axisymmetric near the center, while near the large SMBH influence radius, the galaxy is triaxial. The SMBH separation shrinks rapidly due to dynamical friction, and quickly forms a binary black hole; if we scale our model to the most massive estimate for the NGC1277 black hole, for example, the timescale for the SMBH separation to shrink from nearly a kiloparsec to less than a parsec is roughly 10Myr. By the time the SMBHs form a hard binary, gravitational wave emission dominates, and the black holes coalesce in a mere few Myr. Curiously, these extremely massive binaries appear to nearly bypass the three-body scattering evolutionary phase. Our study suggests that in this extreme case, SMBH coalescence is governed by dynamical friction followed nearly directly by gravitational wave emission, resulting in a rapid and efficient SMBH coalescence timescale. We discuss the implications for gravitational wave event rates and hypervelocity star production.

  6. Effective Conveyor Belt Inspection for Improved Mining Productivity

    SciTech Connect (OSTI)

    Chris Fromme

    2006-06-01

    This document details progress on the project entitled ''Effective Conveyor Belt Inspection for Improved Mining Productivity'' during the period from November 15, 2004 to May 14, 2004. Highlights include fabrication of low-cost prototype hardware, acquisition of infrared thermal data, and initial design of a Smart-Camera based system.

  7. Effective Conveyor Belt Inspection for Improved Mining Productivity

    SciTech Connect (OSTI)

    Chris Fromme

    2006-06-01

    This document details progress on the project entitled ''Effective Conveyor Belt Inspection for Improved Mining Productivity'' during the period from November 15, 2004 to May 14, 2004. Highlights include fabrication of an improved LED lightbar, fabrication of a line-scan sensor head for the Smart-Camera based prototype, and development of prototype vulcanized splice detection algorithms.

  8. ARM - Black Forest News

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Black Forest News ARM Mobile Facility Completes Field Campaign in Germany January 15, 2008 Microwave Radiometers Put to the Test in Germany September 15, 2007 Zeppelin NT Flies for ...

  9. Effective Conveyor Belt Inspection for Improved Mining Productivity

    SciTech Connect (OSTI)

    David LaRose

    2006-07-01

    This document details progress on the project ''Effective Conveyor Belt Inspection for Improved Mining Productivity'' during the period from November 15, 2005 to May 14, 2006. Highlights include significant improvements in the accuracy and reliability of computer-vision based vulcanized splice detection, deployment of the vulcanized splice detection algorithms for daily use in two working mines, and successful demonstration of an early prototype of a Smart-Camera based system for on-site mechanical splice detection in coal mine installations.

  10. Effective Conveyer Belt Inspection for Improved Mining Productivity

    SciTech Connect (OSTI)

    David LaRose

    2006-11-14

    This document details progress on the project ''Effective Conveyor Belt Inspection for Improved Mining Productivity'' during the period from May 15, 2006 to November 14, 2006. Progress during this period includes significant advances in development of a Smart Camera based prototype system for on-site mechanical splice detection, and continued deployment of both the mechanical splice detection system and the vulcanized splice detection system in area coal mines.

  11. Aspects of hairy black holes

    SciTech Connect (OSTI)

    Anabalón, Andrés; Astefanesei, Dumitru

    2015-03-26

    We review the existence of exact hairy black holes in asymptotically flat, anti-de Sitter and de Sitter space-times. We briefly discuss the issue of stability and the charging of the black holes with a Maxwell field.

  12. Lumens Placard (Black) | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    File lumensplacard-black.eps More Documents & Publications Lumens Placard (Black) Lumens Placard (Green) Lumens Placard (Green)

  13. Gasification of black liquor

    DOE Patents [OSTI]

    Kohl, Arthur L.

    1987-07-28

    A concentrated aqueous black liquor containing carbonaceous material and alkali metal sulfur compounds is treated in a gasifier vessel containing a relatively shallow molten salt pool at its bottom to form a combustible gas and a sulfide-rich melt. The gasifier vessel, which is preferably pressurized, has a black liquor drying zone at its upper part, a black liquor solids gasification zone located below the drying zone, and a molten salt sulfur reduction zone which comprises the molten salt pool. A first portion of an oxygen-containing gas is introduced into the gas space in the gasification zone immediatley above the molten salt pool. The remainder of the oxygen-containing gas is introduced into the molten salt pool in an amount sufficient to cause gasification of carbonaceous material entering the pool from the gasification zone but not sufficient to create oxidizing conditions in the pool. The total amount of the oxygen-containing gas introduced both above the pool and into the pool constitutes between 25 and 55% of the amount required for complete combustion of the black liquor feed. A combustible gas is withdrawn from an upper portion of the drying zone, and a melt in which the sulfur content is predominantly in the form of alkali metal sulfide is withdrawn from the molten salt sulfur reduction zone.

  14. Black hole magnetospheres

    SciTech Connect (OSTI)

    Nathanail, Antonios; Contopoulos, Ioannis

    2014-06-20

    We investigate the structure of the steady-state force-free magnetosphere around a Kerr black hole in various astrophysical settings. The solution Ψ(r, θ) depends on the distributions of the magnetic field line angular velocity ω(Ψ) and the poloidal electric current I(Ψ). These are obtained self-consistently as eigenfunctions that allow the solution to smoothly cross the two singular surfaces of the problem, the inner light surface inside the ergosphere, and the outer light surface, which is the generalization of the pulsar light cylinder. Magnetic field configurations that cross both singular surfaces (e.g., monopole, paraboloidal) are uniquely determined. Configurations that cross only one light surface (e.g., the artificial case of a rotating black hole embedded in a vertical magnetic field) are degenerate. We show that, similar to pulsars, black hole magnetospheres naturally develop an electric current sheet that potentially plays a very important role in the dissipation of black hole rotational energy and in the emission of high-energy radiation.

  15. Gasification of black liquor

    DOE Patents [OSTI]

    Kohl, A.L.

    1987-07-28

    A concentrated aqueous black liquor containing carbonaceous material and alkali metal sulfur compounds is treated in a gasifier vessel containing a relatively shallow molten salt pool at its bottom to form a combustible gas and a sulfide-rich melt. The gasifier vessel, which is preferably pressurized, has a black liquor drying zone at its upper part, a black liquor solids gasification zone located below the drying zone, and a molten salt sulfur reduction zone which comprises the molten salt pool. A first portion of an oxygen-containing gas is introduced into the gas space in the gasification zone immediately above the molten salt pool. The remainder of the oxygen-containing gas is introduced into the molten salt pool in an amount sufficient to cause gasification of carbonaceous material entering the pool from the gasification zone but not sufficient to create oxidizing conditions in the pool. The total amount of the oxygen-containing gas introduced both above the pool and into the pool constitutes between 25 and 55% of the amount required for complete combustion of the black liquor feed. A combustible gas is withdrawn from an upper portion of the drying zone, and a melt in which the sulfur content is predominantly in the form of alkali metal sulfide is withdrawn from the molten salt sulfur reduction zone. 2 figs.

  16. Data From HANE-Generated Radiation Belts and the Origin of Diffusion Theory

    SciTech Connect (OSTI)

    Winske, Dan

    2012-07-16

    In this presentation we briefly review some of the published data regarding the artificial radiation belts produced by the Starfish and R2 high altitude nuclear explosions in 1962. The data showed slow temporal variations of the belts in altitude (L) and pitch angle ({alpha}) that could be modeled as a diffusion process. That early work formed the basis for more complex radiation belt diffusion models that are in use at present.

  17. DREAM3D simulations of inner-belt dynamics

    SciTech Connect (OSTI)

    Cunningham, Gregory Scott

    2015-05-26

    A 1973 paper by Lyons and Thorne explains the two-belt structure for electrons in the inner magnetosphere as a balance between inward radial diffusion and loss to the atmosphere, where the loss to the atmosphere is enabled by pitch-angle scattering from Coulomb and wave-particle interactions. In the 1973 paper, equilibrium solutions to a decoupled set of 1D radial diffusion equations, one for each value of the first invariant of motion, ?, were computed to produce the equilibrium two-belt structure. Each 1D radial diffusion equation incorporated an L-and ?-dependent `lifetime' due to the Coulomb and wave-particle interactions. This decoupling of the problem is appropriate under the assumption that radial diffusion is slow in comparison to pitch-angle scattering. However, for some values of ? and L the lifetime associated with pitch-angle scattering is comparable to the timescale associated with radial diffusion, suggesting that the true equilibrium solutions might reflect `coupled modes' involving pitch-angle scattering and radial diffusion and thus requiring a 3D diffusion model. In the work we show here, we have computed the equilibrium solutions using our 3D diffusion model, DREAM3D, that allows for such coupling. We find that the 3D equilibrium solutions are quite similar to the solutions shown in the 1973 paper when we use the same physical models for radial diffusion and pitch-angle scattering from hiss. However, we show that the equilibrium solutions are quite sensitive to various aspects of the physics model employed in the 1973 paper that can be improved, suggesting that additional work needs to be done to understand the two-belt structure.

  18. conventional_gas.pdf

    Gasoline and Diesel Fuel Update (EIA)

    ... Uinta Basin Paradox Basin Arkoma Basin Greater Green River Basin Black Warrior Basin Palo ... Miles Source: Energy Information Administration based on data from HPDI, IN Geological ...

  19. Black Pine Circle Project

    ScienceCinema (OSTI)

    Mytko, Christine

    2014-09-15

    A group of seventh graders from Black Pine Circle school in Berkeley had the opportunity to experience the Advanced Light Source (ALS) as "users" via a collaborative field trip and proposal project. The project culminated with a field trip to the ALS for all seventh graders, which included a visit to the ALS data visualization room, a diffraction demonstration, a beamline tour, and informative sessions about x-rays and tomography presented by ALS scientists.

  20. Black Pine Circle Project

    SciTech Connect (OSTI)

    Mytko, Christine

    2014-03-31

    A group of seventh graders from Black Pine Circle school in Berkeley had the opportunity to experience the Advanced Light Source (ALS) as "users" via a collaborative field trip and proposal project. The project culminated with a field trip to the ALS for all seventh graders, which included a visit to the ALS data visualization room, a diffraction demonstration, a beamline tour, and informative sessions about x-rays and tomography presented by ALS scientists.

  1. First ultraviolet reflectance measurements of several Kuiper Belt objects, Kuiper Belt object satellites, and new ultraviolet measurements of A Centaur

    SciTech Connect (OSTI)

    Stern, S. A.; Schindhelm, E.; Cunningham, N. J.

    2014-05-01

    We observed the 2600-3200 (hereafter, mid-UV) reflectance of two Kuiper Belt Objects (KBOs), two KBO satellites, and a Centaur, using the Hubble Space Telescope (HST) Cosmic Origins Spectrograph (COS). Other than measurements of the Pluto system, these constitute the first UV measurements obtained of KBOs, and KBO satellites, and new HST UV measurements of the Centaur 2060 Chiron. We find significant differences among these objects, constrain the sizes and densities of Haumea's satellites, and report the detection of a possible spectral absorption band in Haumea's spectrum near 3050 . Comparisons of these objects to previously published UV reflectance measurements of Pluto and Charon are also made here.

  2. Ultra-low-frequency wave-driven diffusion of radiation belt relativistic electrons

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Su, Zhenpeng; Zhu, Hui; Xiao, Fuliang; Zong, Q. -G.; Zhou, X. -Z.; Zheng, Huinan; Wang, Yuming; Wang, Shui; Hao, Y. -X.; Gao, Zhonglei; et al

    2015-12-22

    The Van Allen radiation belts are typically two zones of energetic particles encircling the Earth separated by the slot region. How the outer radiation belt electrons are accelerated to relativistic energies remains an unanswered question. Recent studies have presented compelling evidence for the local acceleration by very-low-frequency (VLF) chorus waves. However, there has been a competing theory to the local acceleration, radial diffusion by ultra-low-frequency (ULF) waves, whose importance has not yet been determined definitively. Here we report a unique radiation belt event with intense ULF waves but no detectable VLF chorus waves. So, our results demonstrate that the ULFmore » waves moved the inner edge of the outer radiation belt earthward 0.3 Earth radii and enhanced the relativistic electron fluxes by up to one order of magnitude near the slot region within about 10 h, providing strong evidence for the radial diffusion of radiation belt relativistic electrons.« less

  3. Ultra-low-frequency wave-driven diffusion of radiation belt relativistic electrons

    SciTech Connect (OSTI)

    Su, Zhenpeng; Zhu, Hui; Xiao, Fuliang; Zong, Q. -G.; Zhou, X. -Z.; Zheng, Huinan; Wang, Yuming; Wang, Shui; Hao, Y. -X.; Gao, Zhonglei; He, Zhaoguo; Baker, D. N.; Spence, H. E.; Reeves, G. D.; Blake, J. B.; Wygant, J. R.

    2015-12-22

    The Van Allen radiation belts are typically two zones of energetic particles encircling the Earth separated by the slot region. How the outer radiation belt electrons are accelerated to relativistic energies remains an unanswered question. Recent studies have presented compelling evidence for the local acceleration by very-low-frequency (VLF) chorus waves. However, there has been a competing theory to the local acceleration, radial diffusion by ultra-low-frequency (ULF) waves, whose importance has not yet been determined definitively. Here we report a unique radiation belt event with intense ULF waves but no detectable VLF chorus waves. So, our results demonstrate that the ULF waves moved the inner edge of the outer radiation belt earthward 0.3 Earth radii and enhanced the relativistic electron fluxes by up to one order of magnitude near the slot region within about 10 h, providing strong evidence for the radial diffusion of radiation belt relativistic electrons.

  4. MAIN-BELT COMET P/2012 T1 (PANSTARRS)

    SciTech Connect (OSTI)

    Hsieh, Henry H.; Kaluna, Heather M.; Yang Bin; Haghighipour, Nader; Micheli, Marco; Denneau, Larry; Jedicke, Robert; Kleyna, Jan; Veres, Peter; Wainscoat, Richard J.; Ansdell, Megan; Elliott, Garrett T.; Keane, Jacqueline V.; Meech, Karen J.; Riesen, Timm E.; Sonnett, Sarah; Novakovic, Bojan; Fitzsimmons, Alan; Moskovitz, Nicholas A.; Sheppard, Scott S.; and others

    2013-07-01

    We present initial results from observations and numerical analyses aimed at characterizing the main-belt comet P/2012 T1 (PANSTARRS). Optical monitoring observations were made between 2012 October and 2013 February using the University of Hawaii 2.2 m telescope, the Keck I telescope, the Baade and Clay Magellan telescopes, Faulkes Telescope South, the Perkins Telescope at Lowell Observatory, and the Southern Astrophysical Research Telescope. The object's intrinsic brightness approximately doubles from the time of its discovery in early October until mid-November and then decreases by {approx}60% between late December and early February, similar to photometric behavior exhibited by several other main-belt comets and unlike that exhibited by disrupted asteroid (596) Scheila. We also used Keck to conduct spectroscopic searches for CN emission as well as absorption at 0.7 {mu}m that could indicate the presence of hydrated minerals, finding an upper limit CN production rate of Q{sub CN} < 1.5 Multiplication-Sign 10{sup 23} mol s{sup -1}, from which we infer a water production rate of Q{sub H{sub 2O}}<5 Multiplication-Sign 10{sup 25} mol s{sup -1}, and no evidence of the presence of hydrated minerals. Numerical simulations indicate that P/2012 T1 is largely dynamically stable for >100 Myr and is unlikely to be a recently implanted interloper from the outer solar system, while a search for potential asteroid family associations reveals that it is dynamically linked to the {approx}155 Myr old Lixiaohua asteroid family.

  5. Sandia National Laboratories: Warrior Women

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    specialist at Sandia and an Iraq war veteran. "It is so common now that I am used to it. ... She says that despite everything she went through in war, "I really loved my job in the ...

  6. Black Forest Partners | Open Energy Information

    Open Energy Info (EERE)

    Black Forest Partners Jump to: navigation, search Name: Black Forest Partners Place: San Francisco, California Zip: 94111 Product: San Francisco-based project developer focused on...

  7. BlackGold Biofuels | Open Energy Information

    Open Energy Info (EERE)

    BlackGold Biofuels Jump to: navigation, search Name: BlackGold Biofuels Place: Philadelphia, Pennsylvania Zip: 19107 Product: Philadelphia-based developer of a waste...

  8. Black optic display

    DOE Patents [OSTI]

    Veligdan, James T.

    1997-01-01

    An optical display includes a plurality of stacked optical waveguides having first and second opposite ends collectively defining an image input face and an image screen, respectively, with the screen being oblique to the input face. Each of the waveguides includes a transparent core bound by a cladding layer having a lower index of refraction for effecting internal reflection of image light transmitted into the input face to project an image on the screen, with each of the cladding layers including a cladding cap integrally joined thereto at the waveguide second ends. Each of the cores is beveled at the waveguide second end so that the cladding cap is viewable through the transparent core. Each of the cladding caps is black for absorbing external ambient light incident upon the screen for improving contrast of the image projected internally on the screen.

  9. Grenville foreland thrust belt hidden beneath the eastern US midcontinent

    SciTech Connect (OSTI)

    Hauser, E.C. (Cornell Univ., Ithaca, NY (United States))

    1993-01-01

    Grenville foreland thrust structures are observed beneath the eastern US midcontinent on COCORP (Consortium for Continental Reflection Profiling) line OH-1 and a short seismic line in southwest Ohio. These structures represent the first evidence for a significant Grenville foreland thrust belt preserved in eastern North America. On the COCORP lines, the structures include a thrust ramp anticline and an associated asymmetric syncline. The Grenville front tectonic zone appears to truncate these foreland structures, indicating a later, second phase expressed as a deeply penetrating, out-of-sequence thrust zone associated with the main uplift of the Grenville province on the east. A short, shallow seismic line in southwestern Ohio reveals an east-dipping sequence of prominently layered rocks that may lie above a footwall ramp to a deeper Grenville thrust fault. A drill hole into the less reflective top of this dipping sequence encountered unmetamorphosed sedimentary rocks like those increasingly reported from other drill holes in southwestern Ohio and adjacent states. Although possibly part of a late Precambrian (Keweenawan ) rift, these clastic sedimentary rocks may instead preserve evidence of a heretofore unrecognized Grenville foreland basin in eastern North America. Alternatively these Precambrian sedimentary rocks together with an underlying, but yet undrilled, strongly layered sequence may correlate with similarly layered rocks observed on COCORP and industrial seismic lines within the Middle Proterozoic granite-rhyolite province to the west in Indiana and Illinois and indicate that unmetamorphosed sedimentary material is an important constituent of the granite-rhyolite province. 25 refs., 6 figs.

  10. Dynamical implantation of objects in the Kuiper Belt

    SciTech Connect (OSTI)

    Brasil, P. I. O.

    2014-09-01

    Several models have been suggested in the past to describe the dynamical formation of hot Kuiper Belt objects (hereafter Hot Classicals or HCs for short). Here, we discuss a dynamical mechanism that allows orbits to evolve from the primordial planetesimal disk at ≲ 35 AU to reach the orbital region now occupied by HCs. We performed three different sets of numerical simulations to illustrate this mechanism. Two of these simulations were based on modern theories for the early evolution of the solar system (the Nice and jumping-Jupiter models). The third simulation was performed with the purpose of increasing the resolution at 41-46 AU. The common aspect of these simulations is that Neptune scatters planetesimals from ≲ 35 AU to >40 AU and then undergoes a long phase of slow residual migration. Our results show that to reach an HC orbit, a scattered planetesimal needs to be captured in a mean motion resonance (MMR) with Neptune where the perihelion distance rises due to the Kozai resonance (which occurs in MMRs even for moderate inclinations). Finally, while Neptune is still migrating, the planetesimal is released from the MMR on a stable HC orbit. We show that the orbital distribution of HCs expected from this process provides a reasonable match to observations. The capture efficiency and the mass deposited into the HC region appears to be sensitive to the maximum eccentricity reached by Neptune during the planetary instability phase. Additional work will be needed to resolve this dependency in detail.

  11. COLOR DEPENDENCE IN THE SIZE DISTRIBUTION OF MAIN BELT ASTEROIDS REVISITED

    SciTech Connect (OSTI)

    August, Tyler M.; Wiegert, Paul A.

    2013-06-15

    The size distribution of the asteroid belt is examined with 16956 main belt asteroids detected in data taken from the Canada-France-Hawaii Telescope Legacy Survey in two filters (g' and r'). The cumulative H (absolute magnitude) distribution is examined in both filters, and both match well to simple power laws down to H = 17, with slopes in rough agreement with those reported the literature. This implies that disruptive collisions between asteroids are gravitationally dominated down to at least this size, and probably sub-kilometer scales. The slopes of these distributions appear shallower in the outer belt than the inner belt, and the g' distributions appear slightly steeper than the r'. The slope shallowing in the outer belt may reflect a real compositional difference: the inner asteroid belt has been suggested to consist mostly of stony and/or metallic S-type asteroids, whereas carbonaceous C-types are thought to be more prevalent further from the Sun. No waves are seen in the size distribution above H = 15. Since waves are expected to be produced at the transition from gravitationally-dominated to internal strength-dominated collisions, their absence here may imply that the transition occurs at sub-kilometer scales, much smaller than the H = 17 (diameter {approx} 1.6 km) cutoff of this study.

  12. Category:Map Image Files | Open Energy Information

    Open Energy Info (EERE)

    55 KB Awstwspd100onoff3-1.jpg Awstwspd100onoff3-1.jpg 4.43 MB Banglmetst 221.pdf Banglmetst 221.pdf 5.42 MB Black.Warrior.Basin usgs.map.pdf Black.Warrior.Basin us......

  13. The evolution and hydrocarbon habitat of the Papuan fold belt, PNG

    SciTech Connect (OSTI)

    Dalton, D.G.; Smith, R.I.; Cawley, S.J. )

    1990-05-01

    After over 70 years of hydrocarbon exploration in the Papuan fold belt of PNG (Papua New Guinea) there have been a number of hydrocarbon discoveries over recent years that have confirmed its potential as a significant producing province. The Papuan basin developed during the early Mesozoic as part of the northeast corner of the Australian passive margin. The basin's tertiary evolution and the development of the Papuan fold belt within the Papuan basin has evolved in response to oblique convergence between the northerly moving Australian plate and westerly moving Pacific plate. Restacking of the Mesozoic passive margin sequence within the Papuan Basin was initiated in the early miocene by southward abduction of the Solomon Sea plate and the subsequent collision, in the late Miocene, of the Melanesian Island arc along the northeastern margin of PNG. This later collision provided the driving mechanism for the development of the papuan thrust belt. To date, all the significant hydrocarbon discoveries made within the Papuan fold belt have been located within the frontal zone of the fold belt, which is characterized by relatively simple ramp anticlines and thick-skinned inversion structures. The primary proven reservoir fairway is the Jurassic Toro formation, which is a sequence of stacked submarine bars prograding out across a shallow-marine low-gradient shelf. Geochemical analysis of produced hydrocarbons and samples collected from the many surface seeps found in the fold belt indicate two main families of oil. A model explains the distribution of hydrocarbons discovered to date, which involves Jurassic and Cretaceous source intervals and a complex history of secondary migration and entrapment. The unique technical problems associated with exploration of the Papuan fold belt leave many elements of the proven play systems uncertain, but in so doing, they present many challenges and opportunities for the future.

  14. Black hole mimickers: Regular versus singular behavior

    SciTech Connect (OSTI)

    Lemos, Jose P. S.; Zaslavskii, Oleg B.

    2008-07-15

    Black hole mimickers are possible alternatives to black holes; they would look observationally almost like black holes but would have no horizon. The properties in the near-horizon region where gravity is strong can be quite different for both types of objects, but at infinity it could be difficult to discern black holes from their mimickers. To disentangle this possible confusion, we examine the near-horizon properties, and their connection with far away asymptotic properties, of some candidates to black mimickers. We study spherically symmetric uncharged or charged but nonextremal objects, as well as spherically symmetric charged extremal objects. Within the uncharged or charged but nonextremal black hole mimickers, we study nonextremal {epsilon}-wormholes on the threshold of the formation of an event horizon, of which a subclass are called black foils, and gravastars. Within the charged extremal black hole mimickers we study extremal {epsilon}-wormholes on the threshold of the formation of an event horizon, quasi-black holes, and wormholes on the basis of quasi-black holes from Bonnor stars. We elucidate whether or not the objects belonging to these two classes remain regular in the near-horizon limit. The requirement of full regularity, i.e., finite curvature and absence of naked behavior, up to an arbitrary neighborhood of the gravitational radius of the object enables one to rule out potential mimickers in most of the cases. A list ranking the best black hole mimickers up to the worst, both nonextremal and extremal, is as follows: wormholes on the basis of extremal black holes or on the basis of quasi-black holes, quasi-black holes, wormholes on the basis of nonextremal black holes (black foils), and gravastars. Since in observational astrophysics it is difficult to find extremal configurations (the best mimickers in the ranking), whereas nonextremal configurations are really bad mimickers, the task of distinguishing black holes from their mimickers seems to

  15. Charged rotating dilaton black strings

    SciTech Connect (OSTI)

    Dehghani, M.H.; Farhangkhah, N.

    2005-02-15

    In this paper we, first, present a class of charged rotating solutions in four-dimensional Einstein-Maxwell-dilaton gravity with zero and Liouville-type potentials. We find that these solutions can present a black hole/string with two regular horizons, an extreme black hole or a naked singularity provided the parameters of the solutions are chosen suitable. We also compute the conserved and thermodynamic quantities, and show that they satisfy the first law of thermodynamics. Second, we obtain the (n+1)-dimensional rotating solutions in Einstein-dilaton gravity with Liouville-type potential. We find that these solutions can present black branes, naked singularities or spacetimes with cosmological horizon if one chooses the parameters of the solutions correctly. Again, we find that the thermodynamic quantities of these solutions satisfy the first law of thermodynamics.

  16. Quantum Criticality and Black Holes

    ScienceCinema (OSTI)

    Sachdev, Subir [Harvard University, Cambridge, Massachusetts, United States

    2009-09-01

    I will describe the behavior of a variety of condensed matter systems in the vicinity of zero temperature quantum phase transitions. There is a remarkable analogy between the hydrodynamics of such systems and the quantum theory of black holes. I will show how insights from this analogy have shed light on recent experiments on the cuprate high temperature superconductors. Studies of new materials and trapped ultracold atoms are yielding new quantum phases, with novel forms of quantum entanglement. Some materials are of technological importance: e.g. high temperature superconductors. Exact solutions via black hole mapping have yielded first exact results for transport coefficients in interacting many-body systems, and were valuable in determining general structure of hydrodynamics. Theory of VBS order and Nernst effect in cuprates. Tabletop 'laboratories for the entire universe': quantum mechanics of black holes, quark-gluon plasma, neutrons stars, and big-bang physics.

  17. Black Engineer of the Year Award

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Black Engineer of the Year Award - Sandia Energy Energy Search Icon Sandia Home Locations ... Twitter Google + Vimeo GovDelivery SlideShare Black Engineer of the Year Award Home...

  18. Gravity survey of the southwestern part of the sourthern Utah geothermal belt

    SciTech Connect (OSTI)

    Green, R.T.; Cook, K.L.

    1981-03-01

    A gravity survey covering an area of 6200 km/sup 2/ was made over the southwestern part of the southern Utah geothermal belt. The objective of the gravity survey is to delineate the geologic structures and assist in the understanding of the geothermal potential of the area. A total of 726 new gravity stations together with 205 existing gravity stations, are reduced to give: (1) a complete Bouguer gravity anomaly map, and (2) a fourth-order residual gravity anomaly map; both maps have a 2-mgal contour interval. The complete Bouguer gravity anomaly map shows an east-trending regional gravity belt with a total relief of about 70 mgal which crosses the central portion of the survey area. The gravity belt is attributed to a crustal lateral density variation of 0.1 gm/cc from a depth of 5 to 15 km.

  19. Nonstorm time dropout of radiation belt electron fluxes on 24 September 2013

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Su, Zhenpeng; Gao, Zhonglei; Reeves, Geoffrey D.; Funsten, Herbert O.; Zhu, Hui; Li, Wen; Zheng, Huinan; Wang, Yuming; Wang, Shui; Spence, H. E.; et al

    2016-07-15

    Radiation belt electron flux dropouts during the main phase of geomagnetic storms have received increasing attention in recent years. Here we focus on a rarely reported nonstorm time dropout event observed by Van Allen Probes on 24 September 2013. Within several hours, the radiation belt electron fluxes exhibited a significant (up to 2 orders of magnitude) depletion over a wide range of radial distances (L > 4.5), energies (~500 keV to several MeV) and equatorial pitch angles (0° ≤ αe ≤ 180°). STEERB simulations show that the relativistic electron loss in the region L = 4.5–6.0 was primarily caused bymore » the pitch angle scattering of observed plasmaspheric hiss and electromagnetic ion cyclotron waves. Furthermore, our results emphasize the complexity of radiation belt dynamics and the importance of wave-driven precipitation loss even during nonstorm times.« less

  20. Solar wind conditions leading to efficient radiation belt electron acceleration: A superposed epoch analysis

    SciTech Connect (OSTI)

    Li, W.; Thorne, R. M.; Bortnik, J.; Baker, D. N.; Reeves, G. D.; Kanekal, S. G.; Spence, H. E.; Green, J. C.

    2015-09-07

    In this study by determining preferential solar wind conditions leading to efficient radiation belt electron acceleration is crucial for predicting radiation belt electron dynamics. Using Van Allen Probes electron observations (>1 MeV) from 2012 to 2015, we identify a number of efficient and inefficient acceleration events separately to perform a superposed epoch analysis of the corresponding solar wind parameters and geomagnetic indices. By directly comparing efficient and inefficient acceleration events, we clearly show that prolonged southward Bz, high solar wind speed, and low dynamic pressure are critical for electron acceleration to >1 MeV energies in the heart of the outer radiation belt. We also evaluate chorus wave evolution using the superposed epoch analysis for the identified efficient and inefficient acceleration events and find that chorus wave intensity is much stronger and lasts longer during efficient electron acceleration events, supporting the scenario that chorus waves play a key role in MeV electron acceleration.

  1. Source and seed populations for relativistic electrons: Their roles in radiation belt changes

    SciTech Connect (OSTI)

    Jaynes, A. N.; Baker, D. N.; Singer, H. J.; Rodriguez, J. V.; Loto'aniu, T. M.; Ali, A. F.; Elkington, S. R.; Li, X.; Kanekal, S. G.; Claudepierre, S. G.; Fennell, J. F.; Li, W.; Thorne, R. M.; Kletzing, C. A.; Spence, H. E.; Reeves, G. D.

    2015-09-09

    Strong enhancements of outer Van Allen belt electrons have been shown to have a clear dependence on solar wind speed and on the duration of southward interplanetary magnetic field. However, individual case study analyses also have demonstrated that many geomagnetic storms produce little in the way of outer belt enhancements and, in fact, may produce substantial losses of relativistic electrons. In this study, focused upon a key period in AugustSeptember 2014, we use GOES geostationary orbit electron flux data and Van Allen Probes particle and fields data to study the process of radiation belt electron acceleration. One particular interval, 1322 September, initiated by a short-lived geomagnetic storm and characterized by a long period of primarily northward interplanetary magnetic field (IMF), showed strong depletion of relativistic electrons (including an unprecedented observation of long-lasting depletion at geostationary orbit) while an immediately preceding, and another immediately subsequent, storm showed strong radiation belt enhancement. We demonstrate with these data that two distinct electron populations resulting from magnetospheric substorm activity are crucial elements in the ultimate acceleration of highly relativistic electrons in the outer belt: the source population (tens of keV) that give rise to VLF wave growth and the seed population (hundreds of keV) that are, in turn, accelerated through VLF wave interactions to much higher energies. ULF waves may also play a role by either inhibiting or enhancing this process through radial diffusion effects. Furthermore, if any components of the inner magnetospheric accelerator happen to be absent, the relativistic radiation belt enhancement fails to materialize.

  2. Exploration for hydrocarbons under thrust belts - a challenging new frontier in the Carpathians

    SciTech Connect (OSTI)

    Picha, F.J. )

    1993-09-01

    The Carpathian thrust belt has been explored with mixed results. Large reserves of oil and gas have been found in Romania and the western Ukraine, while exploration in other areas has been disappointing. Deep drilling and seismic profiling, as well as better understanding of structure, however, has contributed to the opening of promising new plays beneath the allochthonous belt. The thin-skinned Carpathian thrust belt is characterized by a long-range tectonic transport over the Neogene foredeep and the underlying European platform. The complex structure of the platform involves Caledonian and Variscan compressional deformation, Mesozoic extension, related to the development of the northern Tethyan margins, and Cenozoic normal faulting and wrenching associated with the Alpine Orogeny. Elements of the platform were also detached and incorporated into the thrust belt proper. In addition to numerous structural plays, significant morphologic features, such as large Paleogene and neogene buried valleys, have been found within the platform margins. Both the valley fill and the associated subsea fans and channels represent promising plays. Generation of hydrocarbons from various source rocks within the platform was greatly enhanced by emplacement of the wedge-shaped Carpathian thrust belt. The low heat flow, typical for the subthrust setting, enabled generation and preservation of hydrocarbons at great depths. Although several oil and gas fields have been found in shallower parts of the platform, the deeper structures (below 5 km) remain mostly unexplored. The complexity and diversity of subthrust geology offers a big challenge to exploration, but also provides an opportunity for finding significant oil and gas accumulations not only in the Carpathians, but elsewhere under thin-skinned thrust belts.

  3. Source and seed populations for relativistic electrons: Their roles in radiation belt changes

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Jaynes, A. N.; Baker, D. N.; Singer, H. J.; Rodriguez, J. V.; Loto'aniu, T. M.; Ali, A. F.; Elkington, S. R.; Li, X.; Kanekal, S. G.; Claudepierre, S. G.; et al

    2015-09-09

    Strong enhancements of outer Van Allen belt electrons have been shown to have a clear dependence on solar wind speed and on the duration of southward interplanetary magnetic field. However, individual case study analyses also have demonstrated that many geomagnetic storms produce little in the way of outer belt enhancements and, in fact, may produce substantial losses of relativistic electrons. In this study, focused upon a key period in August–September 2014, we use GOES geostationary orbit electron flux data and Van Allen Probes particle and fields data to study the process of radiation belt electron acceleration. One particular interval, 13–22more » September, initiated by a short-lived geomagnetic storm and characterized by a long period of primarily northward interplanetary magnetic field (IMF), showed strong depletion of relativistic electrons (including an unprecedented observation of long-lasting depletion at geostationary orbit) while an immediately preceding, and another immediately subsequent, storm showed strong radiation belt enhancement. We demonstrate with these data that two distinct electron populations resulting from magnetospheric substorm activity are crucial elements in the ultimate acceleration of highly relativistic electrons in the outer belt: the source population (tens of keV) that give rise to VLF wave growth and the seed population (hundreds of keV) that are, in turn, accelerated through VLF wave interactions to much higher energies. ULF waves may also play a role by either inhibiting or enhancing this process through radial diffusion effects. Furthermore, if any components of the inner magnetospheric accelerator happen to be absent, the relativistic radiation belt enhancement fails to materialize.« less

  4. Source and seed populations for relativistic electrons: Their roles in radiation belt changes

    SciTech Connect (OSTI)

    Jaynes, A. N.; Baker, D. N.; Singer, H. J.; Rodriguez, J. V.; Loto'aniu, T. M.; Ali, A. F.; Elkington, S. R.; Li, X.; Kanekal, S. G.; Claudepierre, S. G.; Fennell, J. F.; Li, W.; Thorne, R. M.; Kletzing, C. A.; Spence, H. E.; Reeves, G. D.

    2015-09-09

    Strong enhancements of outer Van Allen belt electrons have been shown to have a clear dependence on solar wind speed and on the duration of southward interplanetary magnetic field. However, individual case study analyses also have demonstrated that many geomagnetic storms produce little in the way of outer belt enhancements and, in fact, may produce substantial losses of relativistic electrons. In this study, focused upon a key period in August–September 2014, we use GOES geostationary orbit electron flux data and Van Allen Probes particle and fields data to study the process of radiation belt electron acceleration. One particular interval, 13–22 September, initiated by a short-lived geomagnetic storm and characterized by a long period of primarily northward interplanetary magnetic field (IMF), showed strong depletion of relativistic electrons (including an unprecedented observation of long-lasting depletion at geostationary orbit) while an immediately preceding, and another immediately subsequent, storm showed strong radiation belt enhancement. We demonstrate with these data that two distinct electron populations resulting from magnetospheric substorm activity are crucial elements in the ultimate acceleration of highly relativistic electrons in the outer belt: the source population (tens of keV) that give rise to VLF wave growth and the seed population (hundreds of keV) that are, in turn, accelerated through VLF wave interactions to much higher energies. ULF waves may also play a role by either inhibiting or enhancing this process through radial diffusion effects. Furthermore, if any components of the inner magnetospheric accelerator happen to be absent, the relativistic radiation belt enhancement fails to materialize.

  5. From Pinholes to Black Holes

    SciTech Connect (OSTI)

    Fenimore, Edward E.

    2014-10-06

    Pinhole photography has made major contributions to astrophysics through the use of coded apertures. Coded apertures were instrumental in locating gamma-ray bursts and proving that they originate in faraway galaxies, some from the birth of black holes from the first stars that formed just after the big bang.

  6. Close encounters of three black holes

    SciTech Connect (OSTI)

    Campanelli, Manuela; Lousto, Carlos O.; Zlochower, Yosef

    2008-05-15

    We present the first fully relativistic long-term numerical evolutions of three equal-mass black holes in a system consisting of a third black hole in a close orbit about a black-hole binary. These close-three-black-hole systems have very different merger dynamics from black-hole binaries; displaying complex trajectories, a redistribution of energy that can impart substantial kicks to one of the holes, distinctive waveforms, and suppression of the emitted gravitational radiation. In one configuration the binary is quickly disrupted and the individual holes follow complicated trajectories and merge with the third hole in rapid succession, while in another, the binary completes a half-orbit before the initial merger of one of the members with the third black hole, and the resulting two-black-hole system forms a highly elliptical, well separated binary that shows no significant inspiral for (at least) the first t{approx}1000M of evolution.

  7. AN ASTEROID BELT INTERPRETATION FOR THE TIMING VARIATIONS OF THE MILLISECOND PULSAR B1937+21

    SciTech Connect (OSTI)

    Shannon, R. M.; Cordes, J. M.; Metcalfe, T. S.; Lazio, T. J. W.; Jessner, A.; Kramer, M.; Lazaridis, K. E-mail: cordes@astro.cornell.edu

    2013-03-20

    Pulsar timing observations have revealed companions to neutron stars that include other neutron stars, white dwarfs, main-sequence stars, and planets. We demonstrate that the correlated and apparently stochastic residual times of arrival from the millisecond pulsar B1937+21 are consistent with the signature of an asteroid belt having a total mass {approx}< 0.05 M{sub Circled-Plus }. Unlike the solar system's asteroid belt, the best fit pulsar asteroid belt extends over a wide range of radii, consistent with the absence of any shepherding companions. We suggest that any pulsar that has undergone accretion-driven spin-up and subsequently evaporated its companion may harbor orbiting asteroid mass objects. The resulting timing variations may fundamentally limit the timing precision of some of the other millisecond pulsars. Observational tests of the asteroid belt model include identifying periodicities from individual asteroids, which are difficult; testing for statistical stationarity, which becomes possible when observations are conducted over a longer observing span; and searching for reflected radio emission.

  8. Heavy oil reservoirs in the Tulare Fold Belt, Cymric-McKittrick fields, Kern County, California

    SciTech Connect (OSTI)

    Farley, T. )

    1990-05-01

    The Tulare fold belt is a series of asymmetric, generally northeast-verging anticlines and synclines in the Pliocene-Pleistocene Tulare Formation that trend northwestward through the Cymric-McKittrick fields. Anticlines within the deformed belt generally originated as fault propagation folds above decollements, the most important of which is the regional decollement on top of the Amnicola sand, the basal Tulare unit. The Amnicola decollement is the northeast subsurface extension of the McKittrick thrust, a low-angle fault that has displaced the Miocene Antelope shale over the Pliocene San Joaquin Formation and locally over the Tulare Formation. The Amnicola decollement is itself deformed by folding related to a younger, deeper decollement near the base of the San Joaquin Formation that merges westward with the Amnicola decollement and defines a zone of faulting associated with the McKittrick thrust Heavy oil reservoirs in the Tulare Formation are currently undergoing active development by thermal recovery techniques. In general, the geometry of heavy oil reservoirs is determined by location within the Tulare fold belt combined with the position of a subhorizontal fluid level trap that forms the updip limit of fluid-saturated rock Reservoir geometry is complicated by complex local structure, discontinuous stratigraphy, and partial depletion of heavy oil reservoirs by fluid withdrawal due to gravity drainage. Proper resolution of fold geometry, fault geometry, and position of the fluid level trap is crucial to the design and monitoring of thermal recovery projects within the Tulare fold belt.

  9. NEPTUNE ON TIPTOES: DYNAMICAL HISTORIES THAT PRESERVE THE COLD CLASSICAL KUIPER BELT

    SciTech Connect (OSTI)

    Wolff, Schuyler; Dawson, Rebekah I.; Murray-Clay, Ruth A. E-mail: rdawson@cfa.harvard.edu

    2012-02-20

    The current dynamical structure of the Kuiper Belt was shaped by the orbital evolution of the giant planets, especially Neptune, during the era following planet formation when the giant planets may have undergone planet-planet scattering and/or planetesimal-driven migration. Numerical simulations of this process, while reproducing many properties of the Belt, fail to generate the high inclinations and eccentricities observed for some objects while maintaining the observed dynamically 'cold' population. We present the first of a three-part parameter study of how different dynamical histories of Neptune sculpt the planetesimal disk. Here we identify which dynamical histories allow an in situ planetesimal disk to remain dynamically cold, becoming today's cold Kuiper Belt population. We find that if Neptune undergoes a period of elevated eccentricity and/or inclination, it secularly excites the eccentricities and inclinations of the planetesimal disk. We demonstrate that there are several well-defined regimes for this secular excitation, depending on the relative timescales of Neptune's migration, the damping of Neptune's orbital inclination and/or eccentricity, and the secular evolution of the planetesimals. We model this secular excitation analytically in each regime, allowing for a thorough exploration of parameter space. Neptune's eccentricity and inclination can remain high for a limited amount of time without disrupting the cold classical belt. In the regime of slow damping and slow migration, if Neptune is located (for example) at 20 AU, then its eccentricity must stay below 0.18 and its inclination below 6 Degree-Sign .

  10. Method for determining molten metal pool level in twin-belt continuous casting machines

    DOE Patents [OSTI]

    Kaiser, Timothy D.; Daniel, Sabah S.; Dykes, Charles D.

    1989-03-21

    A method for determining level of molten metal in the input of a continuous metal casting machine having at least one endless, flexible, revolving casting belt with a surface which engages the molten metal to be cast and a reverse, cooled surface along which is directed high velocity liquid coolant includes the steps of predetermining the desired range of positions of the molten metal pool and positioning at least seven heat-sensing transducers in bearing contact with the moving reverse belt surface and spaced in upstream-downstream relationship relative to belt travel spanning the desired pool levels. A predetermined temperature threshold is set, somewhat above coolant temperature and the output signals of the transducer sensors are scanned regarding their output signals indicative of temperatures of the moving reverse belt surface. Position of the molten pool is determined using temperature interpolation between any successive pair of upstream-downstream spaced sensors, which follows confirmation that two succeeding downstream sensors are at temperature levels exceeding threshold temperature. The method accordingly provides high resolution for determining pool position, and verifies the determined position by utilizing full-strength signals from two succeeding downstream sensors. In addition, dual sensors are used at each position spanning the desired range of molten metal pool levels to provide redundancy, wherein only the higher temperature of each pair of sensors at a station is utilized.

  11. Study of movement of the western and central belts of Peninsular Malaysia using GPS data analysis

    SciTech Connect (OSTI)

    Ramli, Siti Hafizah; Samsudin, Abdul Rahim

    2014-09-03

    Since the large earthquakes in Sumatera and Nias, there were some tremors incidents at Bukit Tinggi. Therefore, a study on the earth’s crust movement and the effects of the earthquake in Indonesia on the tectonic blocks of Peninsular Malaysia have been carried out using GPS data analysis. GPS data from five MyRTKnet stations within Peninsular Malaysia have been analyzed to monitor the movement of two major tectonic blocks of Peninsular Malaysia which are the western belt represented by the Behrang (BEHR) and UPM Serdang (UPMS) stations and the central belt represented by Bentong (BENT), Jerantut (JRNT) and Temerloh (TLOH) stations. GPS data recorded from 2005 to 2010 were analysed based on horizontal and vertical displacements of the respective stations by using Trimble Business Centre (TBC) software. Based on the results of accumulated displacements of recorded GPS data from January 2006 to December 2013, it shows that the western belt which represented by UPMS has shifted 0.096m towards northwest with changes of ellipsoidal height of +0.030m while the central belt which represented by TLOH has shifted 0.080m towards northwest with changes of ellipsoidal height of −0.015m. Meanwhile, BENT station which is located on the Bentong-Raub suture zone turns to its original position as well as JRNT station. However, BEHR station which are located in western belt do not show any movements. All of these movements may be due to the influence of reactive faults in the stations area stimulated by several large earthquakes that occurred in 2005 to 2010. Study on using the GPS data analysis and combine with integrated geophysical methods are necessary to understand in detail about the tectonic evolution of Peninsular Malaysia.

  12. Complexity, action, and black holes

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Brown, Adam R.; Roberts, Daniel A.; Susskind, Leonard; Swingle, Brian; Zhao, Ying

    2016-04-18

    In an earlier paper "Complexity Equals Action" we conjectured that the quantum computational complexity of a holographic state is given by the classical action of a region in the bulk (the `Wheeler-DeWitt' patch). We provide calculations for the results quoted in that paper, explain how it fits into a broader (tensor) network of ideas, and elaborate on the hypothesis that black holes are the fastest computers in nature.

  13. Multi-clad black display panel

    SciTech Connect (OSTI)

    Veligdan, James T.; Biscardi, Cyrus; Brewster, Calvin

    2002-01-01

    A multi-clad black display panel, and a method of making a multi-clad black display panel, are disclosed, wherein a plurality of waveguides, each of which includes a light-transmissive core placed between an opposing pair of transparent cladding layers and a black layer disposed between transparent cladding layers, are stacked together and sawed at an angle to produce a wedge-shaped optical panel having an inlet face and an outlet face.

  14. Boson shells harboring charged black holes

    SciTech Connect (OSTI)

    Kleihaus, Burkhard; Kunz, Jutta; Laemmerzahl, Claus; List, Meike

    2010-11-15

    We consider boson shells in scalar electrodynamics coupled to Einstein gravity. The interior of the shells can be empty space, or harbor a black hole or a naked singularity. We analyze the properties of these types of solutions and determine their domains of existence. We investigate the energy conditions and present mass formulae for the composite black hole-boson shell systems. We demonstrate that these types of solutions violate black hole uniqueness.

  15. Black hole birth captured by cosmic voyeurs

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Black hole birth captured by cosmic voyeurs Black hole birth captured by cosmic voyeurs The RAPTOR system is a network of small robotic observatories that scan the skies for optical anomalies such as flashes emanating from a star in its death throes as it collapses and becomes a black hole. November 21, 2013 Los Alamos National Laboratory astrophysicist Tom Vestrand poses with a telescope array that is part of the RAPTOR (RAPid Telescopes for Optical Response) system. RAPTOR is an intelligent

  16. National Conference of Black Mayors, Inc.

    Broader source: Energy.gov [DOE]

    The cooperative agreement enhances the National Conference of Black Mayors, Inc., members' capacity for energy and environmental planning through computer-based technology, Internet access, and a...

  17. Black Coral Capital | Open Energy Information

    Open Energy Info (EERE)

    Coral Capital Jump to: navigation, search Name: Black Coral Capital Address: 55 Union Street, 3rd Floor Place: Boston, Massachusetts Zip: 02108 Region: Greater Boston Area Product:...

  18. Black Mountain Insulation | Open Energy Information

    Open Energy Info (EERE)

    Mountain Insulation Jump to: navigation, search Name: Black Mountain Insulation Place: United Kingdom Sector: Carbon Product: UK-based manufacturer of sheeps wool insulation which...

  19. Black carbon contribution to global warming

    SciTech Connect (OSTI)

    Chylek, P.; Johnson, B.; Kou, L.; Wong, J.

    1996-12-31

    Before the onset of industrial revolution the only important source of black carbon in the atmosphere was biomass burning. Today, black carbon production is divided between the biomass and fossil fuel burning. Black carbon is a major agent responsible for absorption of solar radiation by atmospheric aerosols. Thus black carbon makes other aerosols less efficient in their role of reflecting solar radiation and cooling the earth-atmosphere system. Black carbon also contributes to the absorption of solar radiation by clouds and snow cover. The authors present the results of black carbon concentrations measurements in the atmosphere, in cloud water, in rain and snow melt water collected during the 1992--1996 time period over the southern Nova Scotia. Their results are put into the global and historical perspective by comparing them with the compilation of past measurements at diverse locations and with their measurements of black carbon concentrations in the Greenland and Antarctic ice cores. Black carbon contribution to the global warming is estimated, and compared to the carbon dioxide warming, using the radiative forcing caused by the black carbon at the top of the atmosphere.

  20. Black Hills Energy (Electric) - Residential Energy Efficiency...

    Broader source: Energy.gov (indexed) [DOE]

    Water Heater: 450 Refrigerator: 30unit Freezer: 30unit Dishwasher: 30unit Television: 25unit CFLLED Bulbs: In-store rebates Summary Black Hills Energy (BHE) offers...

  1. Strengthening Our Partnerships with Historically Black Colleges...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Addthis Strengthening Our Partnerships with Historically Black Colleges and Universities Secretary Chu Secretary Chu Former Secretary of Energy Last February, President Obama ...

  2. Efficient Nanostructured Silicon (Black Silicon) PV Devices ...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Traditional AR coatings however, add significant cost to the solar cell manufacturing process. NREL scientists have devised a method and created a nanostructured Si wafer, or black ...

  3. Causticizing for Black Liquor Gasifiers

    SciTech Connect (OSTI)

    Scott Sinquefeld; James Cantrell; Xiaoyan Zeng; Alan Ball; Jeff Empie

    2009-01-07

    The cost-benefit outlook of black liquor gasification (BLG) could be greatly improved if the smelt causticization step could be achieved in situ during the gasification step. Or, at a minimum, the increase in causticizing load associated with BLG could be mitigated. A number of chemistries have been proven successful during black liquor combustion. In this project, three in situ causticizing processes (titanate, manganate, and borate) were evaluated under conditions suitable for high temperature entrained flow BLG, and low temperature steam reforming of black liquor. The evaluation included both thermodynamic modeling and lab experimentation. Titanate and manganate were tested for complete direct causticizing (to thus eliminate the lime cycle), and borates were evaluated for partial causticizing (to mitigate the load increase associated with BLG). Criteria included high carbonate conversion, corresponding hydroxide recovery upon hydrolysis, non process element (NPE) removal, and economics. Of the six cases (three chemistries at two BLG conditions), only two were found to be industrially viable: titanates for complete causticizing during high temperature BLG, and borates for partial causticizing during high temperature BLG. These two cases were evaluated for integration into a gasification-based recovery island. The Larsen [28] BLG cost-benefit study was used as a reference case for economic forecasting (i.e. a 1500 tpd pulp mill using BLG and upgrading the lime cycle). By comparison, using the titanate direct causticizing process yielded a net present value (NPV) of $25M over the NPV of BLG with conventional lime cycle. Using the existing lime cycle plus borate autocausticizing for extra capacity yielded a NPV of $16M.

  4. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    SciTech Connect (OSTI)

    William L. Headrick Jr; Musa Karakus; Jun Wei

    2005-03-01

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective surfaces in

  5. Extraordinary vacuum black string solutions

    SciTech Connect (OSTI)

    Kim, Hyeong-Chan; Lee, Jungjai

    2008-01-15

    In addition to the boosted static solution there are two other classes of stationary stringlike solutions of the vacuum Einstein equation in (4+1) dimensions. Each class is characterized by three parameters of mass, tension, and momentum flow along the fifth coordinate. We analyze the metric properties of one of the two classes, which was previously assumed to be naked singular, and show that the solution spectrum contains black string and wormhole in addition to the known naked singularity as the momentum flow to mass ratio increases. Interestingly, there does not exist new zero momentum solution in these cases.

  6. Geology of oil and gas accumulations in the Papuan fold and thrust belt

    SciTech Connect (OSTI)

    Foo, W.K. )

    1990-06-01

    The high level of exploration interest in Papua New Guinea has developed in large part because of recent discoveries in the western Papuan fold and thrust belt and shows in the adjacent foreland region. Results from recent drilling in the Iagifu/Hedinia area by a Chevron-led joint venture have outlined several pools in culminations along a 50 km long structural axis. Oil and gas are sourced from a thick succession of Jurassic marine shales that were deposited along the rifted northern margin of the Australian plate. Generation and migration is interpreted to have peaked coincident with development of the fold and thrust belt during the Neogene. Trapping occurred as anticlines and thrust sheets developed sequentially from northeast to southwest. Several trends remain untested on lands held by various groups, primarily in the area west of the Juha gas condensate pool.

  7. THE EXTRAORDINARY MULTI-TAILED MAIN-BELT COMET P/2013 P5

    SciTech Connect (OSTI)

    Jewitt, David; Agarwal, Jessica; Weaver, Harold; Mutchler, Max; Larson, Stephen

    2013-11-20

    Hubble Space Telescope observations of main-belt comet P/2013 P5 reveal an extraordinary system of six dust tails that distinguish this object from any other. Observations two weeks apart show dramatic morphological change in the tails while providing no evidence for secular fading of the object as a whole. Each tail is associated with a unique ejection date, revealing continued, episodic mass loss from the 0.24 ± 0.04 km radius nucleus over the last five months. As an inner-belt asteroid and probable Flora family member, the object is likely to be highly metamorphosed and unlikely to contain ice. The protracted period of dust release appears inconsistent with an impact origin, but may be compatible with a body that is losing mass through a rotational instability. We suggest that P/2013 P5 has been accelerated to breakup speed by radiation torques.

  8. THE NUCLEUS OF MAIN-BELT COMET 259P/GARRADD

    SciTech Connect (OSTI)

    MacLennan, Eric M.; Hsieh, Henry H. E-mail: emaclenn@utk.edu

    2012-10-10

    We present observations of the main-belt comet 259P/Garradd, previously known as P/2008 R1 (Garradd), obtained in 2011 and 2012 using the Gemini North Telescope on Mauna Kea in Hawaii and the SOAR telescope at Cerro Pachon in Chile, with the goal of computing the object's phase function and nucleus size. We find an absolute magnitude of H{sub R} = 19.71 {+-} 0.05 mag and slope parameter of G{sub R} = -0.08 {+-} 0.05 for the inactive nucleus, corresponding to an effective nucleus radius of r{sub e} = 0.30 {+-} 0.02 km, assuming an R-band albedo of p{sub R} = 0.05. We also revisit observations reported for 259P while it was active in 2008 to quantify the dust mass loss and compare the object with other known main-belt comets.

  9. A SOUTHERN SKY AND GALACTIC PLANE SURVEY FOR BRIGHT KUIPER BELT OBJECTS

    SciTech Connect (OSTI)

    Sheppard, Scott S.; Udalski, Andrzej; Kubiak, Marcin; Pietrzynski, Grzegorz; Poleski, Radoslaw; Soszynski, Igor; Szymanski, Michal K.; Ulaczyk, Krzysztof; Trujillo, Chadwick

    2011-10-15

    About 2500 deg{sup 2} of sky south of declination -25{sup 0} and/or near the Galactic Plane were surveyed for bright outer solar system objects. This survey is one of the first large-scale southern sky and Galactic Plane surveys to detect dwarf planets and other bright Kuiper Belt Objects in the trans-Neptunian region. The survey was able to obtain a limiting R-band magnitude of 21.6. In all, 18 outer solar system objects were detected, including Pluto which was detected near the Galactic center using optimal image subtraction techniques to remove the high stellar density background. Fourteen of the detections were previously unknown trans-Neptunian objects, demonstrating that the southern sky had not been well searched to date for bright outer solar system objects. Assuming moderate albedos, several of the new discoveries from this survey could be in hydrostatic equilibrium and thus could be considered dwarf planets. Combining this survey with previous surveys from the northern hemisphere suggests that the Kuiper Belt is nearly complete to around 21st magnitude in the R band. All the main dynamical classes in the Kuiper Belt are occupied by at least one dwarf-planet-sized object. The 3:2 Neptune resonance, which is the innermost well-populated Neptune resonance, has several large objects while the main outer Neptune resonances such as the 5:3, 7:4, 2:1, and 5:2 do not appear to have any large objects. This indicates that the outer resonances are either significantly depleted in objects relative to the 3:2 resonance or have a significantly different assortment of objects than the 3:2 resonance. For the largest objects (H < 4.5 mag), the scattered disk population appears to have a few times more objects than the main Kuiper Belt (MKB) population, while the Sedna population could be several times more than that of the MKB.

  10. New Horizons Science Photos from NASA's Pluto-Kuiper Belt Mission

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    DOE provided the power supply for NASA's New Horizons Mission, a mission to the Pluto and Charon, a double-planet system, and the Kuiper Belt. There are science photos posted on the New Horizons website, along with mission photos, spacecraft images, launch photos, posters and renderings that are both scientific and artistic. The images can be searched by keywords, by date, or by subject topic. They can also be browsed as an entire list. Each image has a detailed description.

  11. Near-infrared spectra of high-albedo outer main-belt asteroids

    SciTech Connect (OSTI)

    Kasuga, Toshihiro; Shirahata, Mai; Usui, Fumihiko; Kuroda, Daisuke; Ootsubo, Takafumi; Okamura, Natsuko; Hasegawa, Sunao

    2015-02-01

    Most outer main-belt asteroids have low albedos because of their carbonaceouslike bodies. However, infrared satellite surveys have revealed that some asteroids have high albedos, which may suggest the presence of unusual surface minerals for those primitive objects. We present new near-infrared (1.12.5 ?m) spectra of four outer main-belt asteroids with albedos ? 0.1. The C-complex asteroids (555) Norma and (2542) Calpurnia are featureless and have (50%60%) amorphous Mg pyroxenes that might explain the high albedos. Asteroids (701) Oriola (which is a C-complex asteroid) and (2670) Chuvashia (a D/T-type or M-type asteroid) show possible broad absorption bands (1.52.1 ?m). The feature can be reproduced by either Mg-rich amorphous pyroxene (with 50%60% and 80%95% Mg, respectively) or orthopyroxene (crystalline silicate), which might be responsible for the high albedos. No absorption features of water ice (near 1.5 and 2.0 ?m) are detected in the objects. We discuss the origin of high albedo components in the outer main-belt asteroids and their physical relations to comets.

  12. Exploration within the Sub-Andean Thrust Belt of Southern Bolivia

    SciTech Connect (OSTI)

    Nelson, K.J. )

    1993-02-01

    The Sub-Andean thrust belt of Southern Bolivia is a proven hydrocarbon province. Chevron began a regional study of the area in 1988 and chose the Caipipendi block due to its high potential for significant new oil reserves. A regional work program designed to acquire and integrate seismic data, geologic field data, geochemistry, and gravity data was used to generated structural models, evaluate regional risk components and to detail leads. The structural style within the Caipipendi block is interpreted as being an in sequence, thin skinned thrust belt with eastward verging folds and thrust faults. Tight surface anticlines associated with a Middle Devonian detachment have been later folded by deeper fault bend folds associated with the Silurian detachment. While the tight surface folds are presently producing oil, the deeper broader structures associated with the Silurian detachement have not been tested. Seismic data, utilized for the first time in this part of the Sub-Andean thrust belt, integrated with balanced structural cross sections, is the key to evaluating this new play. Geochemical analysis, including oil biomarker work, indicate that the oils are sourced from the Silurian-Devonian sequence. A generative oil system model formulated by integrating the geochemical analysis with maturation modeling indicates that the Devonian Los Monos formation is the primary oil source. Anticipated reservoirs for the new play are Carboniferous and Devonian sandstones which are also productive elsewhere in the basin.

  13. The quest for better seismic imaging in the sub-Andean thrust belt of southern Bolivia

    SciTech Connect (OSTI)

    Dunn, J.F.; Nelson, K.J.

    1996-08-01

    Like many thrust belts around the world, the sub-Andean thrust belt of southern Bolivia is a difficult place to acquire good seismic data because of the challenges of complex geology, rugged topography, and remote access. This is further aggravated by the fact that we generally desire to image below the surface anticlines, where the conditions for acquiring good data are the worst. Near-surface, steeply-dipping beds also challenge some of the fundamental assumptions of seismic processing. Our approach has been to integrate detailed structural analysis of the surface and subsurface with the seismic interpretation. Seismic imaging of structural geometry is a fundamental risk element in thrust belt hydrocarbon exploration. Acquiring high-quality seismic data in mountainous terrain has been a difficult, time consuming, and costly task. We have exerted considerable effort into finding innovative ways to improve data quality. After an initial round of acquisition in Bolivia, we designed a seismic test program to optimize acquisition parameters. We found that standard parameters were acceptable in the valleys, but larger dynamite charges yielded better results in the mountainous areas where imaging had previously been poor. Additionally, a swath line layout (three parallel receiver lines 200 m apart) helped improve the signal-to-noise ratio. Better static solutions, detailed velocity analysis, and careful structural modeling and depth migrations all help to yield better data and a more reliable interpretation.

  14. Solar wind conditions leading to efficient radiation belt electron acceleration: A superposed epoch analysis

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Li, W.; Thorne, R. M.; Bortnik, J.; Baker, D. N.; Reeves, G. D.; Kanekal, S. G.; Spence, H. E.; Green, J. C.

    2015-09-07

    In this study by determining preferential solar wind conditions leading to efficient radiation belt electron acceleration is crucial for predicting radiation belt electron dynamics. Using Van Allen Probes electron observations (>1 MeV) from 2012 to 2015, we identify a number of efficient and inefficient acceleration events separately to perform a superposed epoch analysis of the corresponding solar wind parameters and geomagnetic indices. By directly comparing efficient and inefficient acceleration events, we clearly show that prolonged southward Bz, high solar wind speed, and low dynamic pressure are critical for electron acceleration to >1 MeV energies in the heart of the outermore » radiation belt. We also evaluate chorus wave evolution using the superposed epoch analysis for the identified efficient and inefficient acceleration events and find that chorus wave intensity is much stronger and lasts longer during efficient electron acceleration events, supporting the scenario that chorus waves play a key role in MeV electron acceleration.« less

  15. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    SciTech Connect (OSTI)

    William L. Headrick Jr; Musa Karakus; Xiaoting Liang; Jun Wei

    2005-04-01

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective surfaces in

  16. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    SciTech Connect (OSTI)

    William L. Headrick Jr; Musa Karakus; Xiaoting Liang; Alireza Rezaie

    2004-10-01

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective surfaces in

  17. Refractory for Black Liquor Gasifiers

    SciTech Connect (OSTI)

    William L. Headrick Jr; Musa Karakus; Xiaoting Liang

    2005-10-01

    The University of Missouri-Rolla identified materials that permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project was to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study attempted to define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials were selected/developed that either react with the gasifier environment to form protective surfaces in-situ; and

  18. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    SciTech Connect (OSTI)

    William L. Headrick Jr; Musa Karakus; Xiaoting Liang

    2005-07-01

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective surfaces in

  19. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    SciTech Connect (OSTI)

    William L. Headrick Jr; Musa Karakus; Xiaoting Liang; Jun Wei

    2005-01-01

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective surfaces in

  20. Refractory for Black Liquor Gasifiers

    SciTech Connect (OSTI)

    William L. Headrick Jr; Alireza Rezaie

    2003-12-01

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the materials problems encountered during the operation of low-pressure high-temperature (LFHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective surfaces in

  1. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    SciTech Connect (OSTI)

    William L. Headrick Jr.; Alireza Rezaie

    2003-12-01

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the materials problems encountered during the operation of low-pressure high-temperature (LFHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective surfaces in

  2. Refractory for Black Liquor Gasifiers

    SciTech Connect (OSTI)

    William L. Headrick Jr; Alireza Rezaie; Xiaoting Liang; Musa Karakus; Jun Wei

    2005-12-01

    The University of Missouri-Rolla identified materials that permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project was to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study attempted to define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials were selected or developed that reacted with the gasifier environment to form protective surfaces in-situ; and

  3. Refractory for Black Liquor Gasifiers

    SciTech Connect (OSTI)

    William L. Headrick Jr; Alireza Rezaie

    2003-08-01

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the materials problems encountered during the operation of low-pressure high-temperature (LFHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective surfaces in

  4. Refractory for Black Liquor Gasifiers

    SciTech Connect (OSTI)

    Robert E. Moore; William L. Headrick; Alireza Rezaie

    2003-03-31

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the materials problems encountered during the operation of low-pressure high-temperature (LFHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective surfaces in

  5. Big Island Demonstration Project - Black Liquor

    SciTech Connect (OSTI)

    2006-08-01

    Black liquor is a papermaking byproduct that also serves as a fuel for pulp and paper mills. This project involves the design, construction, and operation of a black liquor gasifier that will be integrated into Georgia-Pacific's Big Island facility in Virginia, a mill that has been in operation for more than 100 years.

  6. Normal Modes of Black Hole Accretion Disks (Technical Report...

    Office of Scientific and Technical Information (OSTI)

    the modes for different values of the mass and angular momentum of the central black hole. ... PARTICLES AND FIELDS; ACCRETION DISKS; ANGULAR MOMENTUM; BLACK HOLES; EIGENFUNCTIONS; ...

  7. Barrow Black Carbon Source and Impact Study Final Campaign Report...

    Office of Scientific and Technical Information (OSTI)

    Barrow Black Carbon Source and Impact Study Final Campaign Report Citation Details In-Document Search Title: Barrow Black Carbon Source and Impact Study Final Campaign Report The ...

  8. Energy and information near black hole horizons (Journal Article...

    Office of Scientific and Technical Information (OSTI)

    Energy and information near black hole horizons Citation Details In-Document Search Title: Energy and information near black hole horizons The central challenge in trying to ...

  9. Novel mechanism for vorticity generation in black-hole accretion...

    Office of Scientific and Technical Information (OSTI)

    Novel mechanism for vorticity generation in black-hole accretion disks Prev Next Title: Novel mechanism for vorticity generation in black-hole accretion disks Authors: ...

  10. Water telescope's first sky map shows flickering black holes

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Water telescope's first sky map shows flickering black holes Water telescope's first sky map shows flickering black holes The High Altitude Water Cherenkov observatory has released ...

  11. On the time needed to reach an equilibrium structure of the radiation belts

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ripoll, J. -F.; Loran, V.; Cunningham, Gregory Scott; Reeves, Geoffrey D.; Shprits, Y. Y.

    2016-06-04

    In this paper, we complement the notion of equilibrium states of the radiation belts with a discussion on the dynamics and time needed to reach equilibrium. We solve for the equilibrium states obtained using 1D radial diffusion with recently developed hiss and chorus lifetimes at constant values of Kp = 1, 3 and 6. We find that the equilibrium states at moderately low Kp, when plotted vs L-shell (L) and energy (E), display the same interesting S-shape for the inner edge of the outer belt as recently observed by the Van Allen Probes. The S-shape is also produced as themore » radiation belts dynamically evolve toward the equilibrium state when initialized to simulate the buildup after a massive dropout or to simulate loss due to outward diffusion from a saturated state. Physically, this shape, intimately linked with the slot structure, is due to the dependence of electron loss rate (originating from wave-particle interactions) on both energy and L-shell. Equilibrium electron flux profiles are governed by the Biot number (τDiffusion/τloss), with large Biot number corresponding to low fluxes and low Biot number to large fluxes. The time it takes for the flux at a specific (L, E) to reach the value associated with the equilibrium state, starting from these different initial states, is governed by the initial state of the belts, the property of the dynamics (diffusion coefficients), and the size of the domain of computation. Its structure shows a rather complex scissor form in the (L, E) plane. The equilibrium value (phase space density or flux) is practically reachable only for selected regions in (L, E) and geomagnetic activity. Convergence to equilibrium requires hundreds of days in the inner belt for E > 300 keV and moderate Kp (≤3). It takes less time to reach equilibrium during disturbed geomagnetic conditions (Kp ≥ 3), when the system evolves faster. Restricting our interest to the slot region, below L = 4, we find that only small regions in (L, E) space

  12. THE COLOR DIFFERENCES OF KUIPER BELT OBJECTS IN RESONANCE WITH NEPTUNE

    SciTech Connect (OSTI)

    Sheppard, Scott S.

    2012-12-01

    The optical colors of 58 objects in mean motion resonance with Neptune were obtained. The various Neptune resonant populations were found to have significantly different surface color distributions. The 5:3 and 7:4 resonances have semimajor axes near the middle of the main Kuiper Belt and both are dominated by ultra-red material (spectral gradient: S {approx}> 25). The 5:3 and 7:4 resonances have statistically the same color distribution as the low-inclination 'cold' classical belt. The inner 4:3 and distant 5:2 resonances have objects with mostly moderately red colors (S {approx} 15), similar to the scattered and detached disk populations. The 2:1 resonance, which is near the outer edge of the main Kuiper Belt, has a large range of colors with similar numbers of moderately red and ultra-red objects at all inclinations. The 2:1 resonance was also found to have a very rare neutral colored object showing that the 2:1 resonance is really a mix of all object types. The inner 3:2 resonance, like the outer 2:1, has a large range of objects from neutral to ultra-red. The Neptune Trojans (1:1 resonance) are only slightly red (S {approx} 9), similar to the Jupiter Trojans. The inner 5:4 resonance only has four objects with measured colors but shows equal numbers of ultra-red and moderately red objects. The 9:5, 12:5, 7:3, 3:1, and 11:3 resonances do not have reliable color distribution statistics since few objects have been observed in these resonances, though it appears noteworthy that all three of the measured 3:1 objects have only moderately red colors, similar to the 4:3 and 5:2 resonances. The different color distributions of objects in mean motion resonance with Neptune are likely a result from the disruption of the primordial Kuiper Belt from the scattering and migration of the giant planets. The few low-inclination objects known in the outer 2:1 and 5:2 resonances are mostly only moderately red. This suggests if the 2:1 and 5:2 have a cold low-inclination component

  13. 2007 TY430: A COLD CLASSICAL KUIPER BELT TYPE BINARY IN THE PLUTINO POPULATION

    SciTech Connect (OSTI)

    Sheppard, Scott S.; Ragozzine, Darin; Trujillo, Chadwick

    2012-03-15

    Kuiper Belt object 2007 TY430 is the first wide, equal-sized, binary known in the 3:2 mean motion resonance with Neptune. The two components have a maximum separation of about 1 arcsec and are on average less than 0.1 mag different in apparent magnitude with identical ultra-red colors (g - i = 1.49 {+-} 0.01 mag). Using nearly monthly observations of 2007 TY430 from 2007 to 2011, the orbit of the mutual components was found to have a period of 961.2 {+-} 4.6 days with a semi-major axis of 21000 {+-} 160 km and eccentricity of 0.1529 {+-} 0.0028. The inclination with respect to the ecliptic is 15.68 {+-} 0.22 deg and extensive observations have allowed the mirror orbit to be eliminated as a possibility. The total mass for the binary system was found to be 7.90 {+-} 0.21 Multiplication-Sign 10{sup 17} kg. Equal-sized, wide binaries and ultra-red colors are common in the low-inclination 'cold' classical part of the Kuiper Belt and likely formed through some sort of three-body interactions within a much denser Kuiper Belt. To date 2007 TY430 is the only ultra-red, equal-sized binary known outside of the classical Kuiper Belt population. Numerical simulations suggest 2007 TY430 is moderately unstable in the outer part of the 3:2 resonance and thus 2007 TY430 is likely an escaped 'cold' classical object that later got trapped in the 3:2 resonance. Similar to the known equal-sized, wide binaries in the cold classical population, the binary 2007 TY430 requires a high albedo and very low density structure to obtain the total mass found for the pair. For a realistic minimum density of 0.5 g cm{sup -3} the albedo of 2007 TY430 would be greater than 0.17. For reasonable densities, the radii of either component should be less than 60 km, and thus the relatively low eccentricity of the binary is interesting since no tides should be operating on the bodies at their large distances from each other. The low prograde inclination of the binary also makes it unlikely that the Kozai

  14. Refractory for Black Liquor Gasifiers

    SciTech Connect (OSTI)

    William L. Headrick Jr; Musa Karakus; Xiaoting Laing

    2005-10-01

    The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective surfaces in

  15. Early black hole signals at the LHC

    SciTech Connect (OSTI)

    Koch, Ben; Bleicher, Marcus; Stoecker, Horst

    2007-10-26

    The production of mini black holes due to large extra dimensions is a speculative but possible scenario. We survey estimates for di-jet suppression, and multi-mono-jet emission due to black hole production. We further look for a possible sub-scenario which is the formation of a stable or meta-stable black hole remnant (BHR). We show that the beauty of such objects is, that they are relatively easy to observe, even in the early phase of LHC running.

  16. Department of Energy Research Opportunities for Historically Black Colleges

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    and Universities | Department of Energy Department of Energy Research Opportunities for Historically Black Colleges and Universities Department of Energy Research Opportunities for Historically Black Colleges and Universities Information about the Department's laboratories, funding opportunities, partnerships with Historically Black Colleges and Universities, WDTS Program Mission. Department of Energy Research Opportunities for Historically Black Colleges and Universities (472.61 KB) More

  17. black out | OpenEI Community

    Open Energy Info (EERE)

    Dc(266) Contributor 31 October, 2014 - 10:58 What do you know about the grid? black out brown out bulk power system electricity grid future grid grid history security Smart Grid...

  18. Spectral line broadening in magnetized black holes

    SciTech Connect (OSTI)

    Frolov, Valeri P.; Shoom, Andrey A.; Tzounis, Christos E-mail: ashoom@ualberta.ca

    2014-07-01

    We consider weakly magnetized non-rotating black holes. In the presence of a regular magnetic field the motion of charged particles in the vicinity of a black hole is modified. As a result, the position of the innermost stable circular orbit (ISCO) becomes closer to the horizon. When the Lorentz force is repulsive (directed from the black hole) the ISCO radius can reach the gravitational radius. In the process of accretion charged particles (ions) of the accreting matter can be accumulated near their ISCO, while neutral particles fall down to the black hole after they reach 6M radius. The sharp spectral line Fe α, emitted by iron ions at such orbits, is broadened when the emission is registered by a distant observer. In this paper we study this broadening effect and discuss how one can extract information concerning the strength of the magnetic field from the observed spectrum.

  19. Black Emerald Group | Open Energy Information

    Open Energy Info (EERE)

    Group Jump to: navigation, search Name: Black Emerald Group Address: 4 Park Place Place: London, United Kingdom Zip: SW1A 1LP Product: Investment banking firm specializing in...

  20. New Horizons Science Photos from NASA's Pluto-Kuiper Belt Mission

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    DOE provided the power supply for NASA's New Horizons Mission, a mission to the Pluto and Charon, a double-planet system, and the Kuiper Belt. There are 61 science photos posted on the New Horizons website, along with mission photos, spacecraft images, launch photos, posters and renderings that are both scientific and artistic. Dates range from June of 2006 to February of 2008. The images can be searched by keywords, by date, or by subject topic. They can also be browsed as an entire list. Each image has a detailed description.

  1. Black Pine Engineering Wins Clean Energy Trust Clean Energy Challenge |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy Black Pine Engineering Wins Clean Energy Trust Clean Energy Challenge Black Pine Engineering Wins Clean Energy Trust Clean Energy Challenge April 11, 2014 - 11:20am Addthis Black Pine Engineering's pilot compressor in California. The team won the Clean Energy Trust Clean Energy Challenge, securing its spot as a regional finalist in the National Clean Energy Business Plan Competition. | Photo courtesy of Black Pine Engineering Black Pine Engineering's pilot compressor in

  2. Black Silicon Etching - Energy Innovation Portal

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Solar Photovoltaic Solar Photovoltaic Find More Like This Return to Search Black Silicon Etching Award-winning, efficient, and inexpensive photovoltaic technology National Renewable Energy Laboratory Contact NREL About This Technology Three silicon wafers, showing absorbed light: (left) micron-scale texture, (center) NREL&rsquo;s Black Silicon Etch, and (right) micron-scale texture with an antireflective coating. Three silicon wafers, showing absorbed light: (left) micron-scale texture,

  3. Warrior Girl Corporation | Open Energy Information

    Open Energy Info (EERE)

    Girl Corporation Region: United States Sector: Marine and Hydrokinetic Phone Number: 305-607-9518 Website: http: This company is listed in the Marine and Hydrokinetic Technology...

  4. Re-Entries: New strategies in development zones at the Orinoco Oil Belt

    SciTech Connect (OSTI)

    Gonzalez, R.; Briceno, M.; Figueroa, J.; Bolanos, C.

    1996-08-01

    Drilling of horizontal wells in Venezuela began in the Orinoco Oil Belt with the wells CI-87 and CI-97 in the J-20 block, drilled in 1989 and 1990, respectively. Well CI-87 produces up to 1000 BPD without steam injection. Due to the success of this well, the exploitation strategy was oriented toward re-entry and sidetracking wells with mechanical problems, high water cut and low potential. The purpose of this programme was to enhance drainage patterns, access new reservoirs through existing bores, and increase oil production while reducing per-barrel costs. Eighteen (18) wells were re-drilled in different pay zones such as O-12, O-13, O-14 and O-15 with horizontal sections between a thousand feet and one thousand six hundred feet. Those wells were completed with progressive cavity pumps, sucker rod beam pumps and electrical submersible pumps. Presented in this paper are the results of the re-entries at the Orinoco Oil Belt and the future re-entry strategy.

  5. OBSERVATIONAL AND DYNAMICAL CHARACTERIZATION OF MAIN-BELT COMET P/2010 R2 (La Sagra)

    SciTech Connect (OSTI)

    Hsieh, Henry H.; Yang Bin; Haghighipour, Nader; Jedicke, Robert; Wainscoat, Richard J.; Denneau, Larry; Kaluna, Heather M.; Kleyna, Jan; Novakovic, Bojan; Abe, Shinsuke; Chen Wenping; Ip, Wing; Kinoshita, Daisuke; Fitzsimmons, Alan; Lacerda, Pedro; Granvik, Mikael; Grav, Tommy; Knight, Matthew M.; Lisse, Carey M.; Maclennan, Eric; and others

    2012-05-15

    We present observations of the recently discovered comet-like main-belt object P/2010 R2 (La Sagra) obtained by Pan-STARRS1 and the Faulkes Telescope-North on Haleakala in Hawaii, the University of Hawaii 2.2 m, Gemini-North, and Keck I telescopes on Mauna Kea, the Danish 1.54 m telescope (operated by the MiNDSTEp consortium) at La Silla, and the Isaac Newton Telescope on La Palma. An antisolar dust tail is observed to be present from 2010 August through 2011 February, while a dust trail aligned with the object's orbit plane is also observed from 2010 December through 2011 August. Assuming typical phase darkening behavior, P/La Sagra is seen to increase in brightness by >1 mag between 2010 August and December, suggesting that dust production is ongoing over this period. These results strongly suggest that the observed activity is cometary in nature (i.e., driven by the sublimation of volatile material), and that P/La Sagra is therefore the most recent main-belt comet to be discovered. We find an approximate absolute magnitude for the nucleus of H{sub R} = 17.9 {+-} 0.2 mag, corresponding to a nucleus radius of {approx}0.7 km, assuming an albedo of p = 0.05. Comparing the observed scattering surface areas of the dust coma to that of the nucleus when P/La Sagra was active, we find dust-to-nucleus area ratios of A{sub d} /A{sub N} = 30-60, comparable to those computed for fellow main-belt comets 238P/Read and P/2008 R1 (Garradd), and one to two orders of magnitude larger than for two other main-belt comets (133P/Elst-Pizarro and 176P/LINEAR). Using optical spectroscopy to search for CN emission, we do not detect any conclusive evidence of sublimation products (i.e., gas emission), finding an upper limit CN production rate of Q{sub CN} < 6 Multiplication-Sign 10{sup 23} mol s{sup -1}, from which we infer an H{sub 2}O production rate of Q{sub H{sub 2O}} < 10{sup 26} mol s{sup -1}. Numerical simulations indicate that P/La Sagra is dynamically stable for >100 Myr

  6. T-534: Vulnerability in the PDF distiller of the BlackBerry Attachment...

    Broader source: Energy.gov (indexed) [DOE]

    PROBLEM: Vulnerability in the PDF distiller of the BlackBerry Attachment Service for the BlackBerry Enterprise Server. PLATFORM: * BlackBerry Enterprise Server Express version...

  7. Rotating black hole thermodynamics with a particle probe

    SciTech Connect (OSTI)

    Gwak, Bogeun; Lee, Bum-Hoon

    2011-10-15

    The thermodynamics of Myers-Perry black holes in general dimensions are studied using a particle probe. When undergoing particle absorption, the changes of the entropy and irreducible mass are shown to be dependent on the particle radial momentum. The black hole thermodynamic behaviors are dependent on dimensionality for specific rotations. For a 4-dimensional Kerr black hole, its black hole properties are maintained for any particle absorption. 5-dimensional black holes can avoid a naked ring singularity by absorbing a particle in specific momenta ranges. Black holes over 6 dimensions become ultraspinning black holes through a specific form of particle absorption. The microscopical changes are interpreted in limited cases of Myers-Perry black holes using Kerr/CFT correspondence. We systematically describe the black hole properties changed by particle absorption in all dimensions.

  8. THE BLACK HOLE FORMATION PROBABILITY

    SciTech Connect (OSTI)

    Clausen, Drew; Piro, Anthony L.; Ott, Christian D.

    2015-02-01

    A longstanding question in stellar evolution is which massive stars produce black holes (BHs) rather than neutron stars (NSs) upon death. It has been common practice to assume that a given zero-age main sequence (ZAMS) mass star (and perhaps a given metallicity) simply produces either an NS or a BH, but this fails to account for a myriad of other variables that may effect this outcome, such as spin, binarity, or even stochastic differences in the stellar structure near core collapse. We argue that instead a probabilistic description of NS versus BH formation may be better suited to account for the current uncertainties in understanding how massive stars die. We present an initial exploration of the probability that a star will make a BH as a function of its ZAMS mass, P {sub BH}(M {sub ZAMS}). Although we find that it is difficult to derive a unique P {sub BH}(M {sub ZAMS}) using current measurements of both the BH mass distribution and the degree of chemical enrichment by massive stars, we demonstrate how P {sub BH}(M {sub ZAMS}) changes with these various observational and theoretical uncertainties. We anticipate that future studies of Galactic BHs and theoretical studies of core collapse will refine P {sub BH}(M {sub ZAMS}) and argue that this framework is an important new step toward better understanding BH formation. A probabilistic description of BH formation will be useful as input for future population synthesis studies that are interested in the formation of X-ray binaries, the nature and event rate of gravitational wave sources, and answering questions about chemical enrichment.

  9. Rotating black lens solution in five dimensions

    SciTech Connect (OSTI)

    Chen Yu; Teo, Edward

    2008-09-15

    It has recently been shown that a stationary, asymptotically flat vacuum black hole in five space-time dimensions with two commuting axial symmetries must have an event horizon with either a spherical, ring or lens-space topology. In this paper, we study the third possibility, a so-called black lens with L(n,1) horizon topology. Using the inverse scattering method, we construct a black-lens solution with the simplest possible rod structure, and possessing a single asymptotic angular momentum. Its properties are then analyzed; in particular, it is shown that there must either be a conical singularity or a naked curvature singularity present in the space-time.

  10. Electric field effect in ultrathin black phosphorus

    SciTech Connect (OSTI)

    Koenig, Steven P.; Schmidt, Hennrik; Doganov, Rostislav A.; Castro Neto, A. H.; Özyilmaz, Barbaros

    2014-03-10

    Black phosphorus exhibits a layered structure similar to graphene, allowing mechanical exfoliation of ultrathin single crystals. Here, we demonstrate few-layer black phosphorus field effect devices on Si/SiO{sub 2} and measure charge carrier mobility in a four-probe configuration as well as drain current modulation in a two-point configuration. We find room-temperature mobilities of up to 300 cm{sup 2}/Vs and drain current modulation of over 10{sup 3}. At low temperatures, the on-off ratio exceeds 10{sup 5}, and the device exhibits both electron and hole conduction. Using atomic force microscopy, we observe significant surface roughening of thin black phosphorus crystals over the course of 1 h after exfoliation.

  11. LANL LDRD-funded project: Test particle simulations of energetic ions in natural and artificial radiation belts

    SciTech Connect (OSTI)

    Cowee, Misa; Liu, Kaijun; Friedel, Reinhard H.; Reeves, Geoffrey D.

    2012-07-17

    We summarize the scientific problem and work plan for the LANL LDRD-funded project to use a test particle code to study the sudden de-trapping of inner belt protons and possible cross-L transport of debris ions after a high altitude nuclear explosion (HANE). We also discuss future application of the code for other HANE-related problems.

  12. The Cordilleran foreland thrust belt in northwestern Montana and northern Idaho from COCORP and industry seismic reflection data

    SciTech Connect (OSTI)

    Yoos, T.R.; Potter, C.J.; Thigpen, J.L.; Brown, L.D. (Cornell Univ., Ithaca, NY (United States))

    1991-06-01

    COCORP and petroleum industry seismic reflection profiles in northwestern Montana reveal the structure of the Cordilleran foreland thrust belt. The Front Ranges consist of thick thrust sheets containing Precambrian Belt Supergroup and Paleozoic miogeoclinal shelf rocks above a thin remnant of Paleozoic rocks and gently westward-dipping North American basement. Interpretation of the seismic data and results from a recent petroleum exploration well suggest that 15-22 km of Precambrian Belt Supergroup sedimentary rocks are present in several thrust plates beneath the eastern Purcell anticlinorium. Previous hypotheses of a large mass of Paleozoic miogeoclinal sedimentary rocks or slices of crystalline basement located beneath the eastern Purcell anticlinorium do not appear to be supported by the data. The easternmost occurrence of allochthonous basement is interpreted to be in the western part of the anticlinorium near the Montana-Idaho border. Comparison of the Cordilleran foreland thrust belt in northwestern Montana and southern Canada suggest that a change in the deep structure of the Purcell anticlinorium occurs along strike. The anticlinorium in southern Canada has been interpreted as a hanging-wall anticline that was thrust over the western edge of thick Proterozoic North American basement, whereas in northwestern Montana the anticlinorium appears to consist of a complex series of thrust sheets above highly attenuated North American basement.

  13. Wave-driven butterfly distribution of Van Allen belt relativistic electrons

    SciTech Connect (OSTI)

    Xiao, Fuliang; Yang, Chang; Su, Zhenpeng; Zhou, Qinghua; He, Zhaoguo; He, Yihua; Baker, D. N.; Spence, H. E.; Funsten, H. O.; Blake, J. B.

    2015-10-05

    Van Allen radiation belts consist of relativistic electrons trapped by Earth's magnetic field. Trapped electrons often drift azimuthally around Earth and display a butterfly pitch angle distribution of a minimum at 90° further out than geostationary orbit. This is usually attributed to drift shell splitting resulting from day–night asymmetry in Earth’s magnetic field. However, direct observation of a butterfly distribution well inside of geostationary orbit and the origin of this phenomenon have not been provided so far. Here we report high-resolution observation that a unusual butterfly pitch angle distribution of relativistic electrons occurred within 5 Earth radii during the 28 June 2013 geomagnetic storm. In conclusion, simulation results show that combined acceleration by chorus and magnetosonic waves can successfully explain the electron flux evolution both in the energy and butterfly pitch angle distribution. Finally, the current provides a great support for the mechanism of wave-driven butterfly distribution of relativistic electrons.

  14. Variscan fold belt and its foreland in western Europe from late Carboniferous to Permian time

    SciTech Connect (OSTI)

    Mascle, A.; Benard, F.; Cazes, M.; Le Gall, B.

    1988-08-01

    The Variscan front was emplaced in the Later Carboniferous with a south-to-north or southeast-to-northwest-trending vergence of thrusting. At the same time, folds were formed in the foreland. In England and southern Scotland, such structures were induced by an east-west direction of shortening, followed by a more subdued north-south compressive event. In Stephanian time, isolated basins developed on the Hercynian belt. In the Massif Central Marues Massif, they are closely related to transcurrent faults which developed in response to north-south-trending compressive stresses. The distribution of stresses completely changed in Early Permian time when extension dominated almost everywhere. Three kinds of basins developed at that time: those related to the relaxation of stresses on the Hercynian range, a north-south-trending rift system in the western United Kingdom and the North Sea, and a broad flexural evaporitic basin from eastern England to Poland.

  15. SUBLIMATION-DRIVEN ACTIVITY IN MAIN-BELT COMET 313P/GIBBS

    SciTech Connect (OSTI)

    Hsieh, Henry H.; Hainaut, Olivier; Novaković, Bojan; Bolin, Bryce; Denneau, Larry; Haghighipour, Nader; Kleyna, Jan; Meech, Karen J.; Schunova, Eva; Wainscoat, Richard J.; Fitzsimmons, Alan; Kokotanekova, Rosita; Snodgrass, Colin; Lacerda, Pedro; Micheli, Marco; Moskovitz, Nick; Wasserman, Lawrence; Waszczak, Adam

    2015-02-10

    We present an observational and dynamical study of newly discovered main-belt comet 313P/Gibbs. We find that the object is clearly active both in observations obtained in 2014 and in precovery observations obtained in 2003 by the Sloan Digital Sky Survey, strongly suggesting that its activity is sublimation-driven. This conclusion is supported by a photometric analysis showing an increase in the total brightness of the comet over the 2014 observing period, and dust modeling results showing that the dust emission persists over at least three months during both active periods, where we find start dates for emission no later than 2003 July 24 ± 10 for the 2003 active period and 2014 July 28 ± 10 for the 2014 active period. From serendipitous observations by the Subaru Telescope in 2004 when the object was apparently inactive, we estimate that the nucleus has an absolute R-band magnitude of H{sub R} = 17.1 ± 0.3, corresponding to an effective nucleus radius of r{sub e} ∼ 1.00 ± 0.15 km. The object’s faintness at that time means we cannot rule out the presence of activity, and so this computed radius should be considered an upper limit. We find that 313P’s orbit is intrinsically chaotic, having a Lyapunov time of T{sub l} = 12,000 yr and being located near two three-body mean-motion resonances with Jupiter and Saturn, 11J-1S-5A and 10J+12S-7A, yet appears stable over >50 Myr in an apparent example of stable chaos. We furthermore find that 313P is the second main-belt comet, after P/2012 T1 (PANSTARRS), to belong to the ∼155 Myr old Lixiaohua asteroid family.

  16. Structural styles of subandean fold and thrust belt of Peru and Southern Ecuador

    SciTech Connect (OSTI)

    Aleman, A.M.

    1988-01-01

    Along-strike variations in structural styles of the east-verging Subandean fold and thrust belt (SAFTB) in Peru and southern Ecuador are controlled by the presence or absence of thick Late Permian to Jurassic evaporite sequences rather than changes in subducting plate geometries as has been suggested previously for the Andes. Salt distribution and thickness have not only controlled the styles and segmentation along the SAFTB but also have been important factors in strike variations across the belt. The southern Ecuador SAFTB lacks significant evaporite units and is characterized by thick-skinned deformation that encompasses high-angle reverse faults, and broad, low-amplitude folds. The style changes to thin-skinned deformation near 2S lat. and it is well illustrated in the Santiago and Huallaga basins where thick evaporite units are present. This segment is characterized by a major decollement on the salt, grabens formed by salt withdrawal from reactivation of thrust faults as listric normal faults, salt piercement at or near synclinal axes, and periclines and asymmetric folds. The frontal thrust of this thin-skinned segment consists of box, overturned and upright folds above shallow salt domes, and by a major backthrust at the mountain front. This segment extends to 1030'S lat., near Oxapampa, Peru, where the thin-skinned SAFTB is narrow and changes across strike to a thick-skinned deformation as the evaporite units thin and disappear eastward. South of 1030'S lat., a new thick-skinned deformation segment is present in southern Peru and characterizes most of the deformation in the SAFTB of the Ucayali and Madre De Dios basins.

  17. A PHOTOMETRIC SYSTEM FOR DETECTION OF WATER AND METHANE ICES ON KUIPER BELT OBJECTS

    SciTech Connect (OSTI)

    Trujillo, Chadwick A.; Sheppard, Scott S.; Schaller, Emily L. E-mail: sheppard@dtm.ciw.edu

    2011-04-01

    We present a new near-infrared photometric system for detection of water ice and methane ice in the solar system. The system consists of two medium-band filters in the K-band region of the near-infrared, which are sensitive to water ice and methane ice, plus continuum observations in the J band and Y band. The primary purpose of this system is to distinguish between three basic types of Kuiper Belt Objects (KBOs)-those rich in water ice, those rich in methane ice, and those with little absorbance. In this work, we present proof-of-concept observations of 51 KBOs using our filter system, 21 of which have never been observed in the near-infrared spectroscopically. We show that our custom photometric system is consistent with previous spectroscopic observations while reducing telescope observing time by a factor of {approx}3. We use our filters to identify Haumea collisional family members, which are thought to be collisional remnants of a much larger body and are characterized by large fractions of water ice on their surfaces. We add 2009 YE{sub 7} to the Haumea collisional family based on our water ice band observations (J - H{sub 2}O = -1.03 {+-} 0.27) which indicate a high amount of water ice absorption, our calculated proper orbital elements, and the neutral optical colors we measured, V - R = 0.38 {+-} 0.04, which are all consistent with the rest of the Haumea family. We identify several objects dynamically similar to Haumea as being distinct from the Haumea family as they do not have water ice on their surfaces. In addition, we find that only the largest KBOs have methane ice, and Haumea itself has significantly less water ice absorption than the smaller Haumea family members. We find no evidence for other families in the Kuiper Belt.

  18. Non-diffusive resonant acceleration of electrons in the radiation belts

    SciTech Connect (OSTI)

    Artemyev, A. V.; Krasnoselskikh, V. V.; Agapitov, O. V.; Rolland, G.

    2012-12-15

    We describe a mechanism of resonant electron acceleration by oblique high-amplitude whistler waves under conditions typical for the Earth radiation belts. We use statistics of spacecraft observations of whistlers in the Earth radiation belts to obtain the dependence of the angle {theta} between the wave-normal and the background magnetic field on magnetic latitude {lambda}. According to this statistics, the angle {theta} already approaches the resonance cone at {lambda}{approx}15 Degree-Sign and remains close to it up to {lambda}{approx}30 Degree-Sign -40 Degree-Sign on the dayside. The parallel component of the electrostatic field of whistler waves often increases around {lambda}{approx}15 Degree-Sign up to one hundred of mV/m. We show that due to this increase of the electric field, the whistler waves can trap electrons into the potential well via wave particle resonant interaction corresponding to Landau resonance. Trapped electrons then move with the wave to higher latitudes where they escape from the resonance. Strong acceleration is favored by adiabatic invariance along the increasing magnetic field, which continuously transfers the parallel energy gained to perpendicular energy, allowing resonance to be reached and maintained. The concomitant increase of the wave phase velocity allows for even stronger relative acceleration at low energy <50keV. Each trapping-escape event of electrons of {approx}10keV to 100 keV results in an energy gain of up to 100 keV in the inhomogeneous magnetic field of the Earth dipole. For electrons with initial energy below 100 keV, such rapid acceleration should hasten their drop into the loss-cone and their precipitation into the atmosphere. We discuss the role of the considered mechanism in the eventual formation of a trapped distribution of relativistic electrons for initial energies larger than 100 keV and in microbursts precipitations of lower energy particles.

  19. Black Friday Savings All Year 'Round | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Black Friday Savings All Year 'Round Black Friday Savings All Year 'Round November 21, 2011 - 3:58pm Addthis Chris Stewart Senior Communicator at DOE's National Renewable Energy ...

  20. Black River Farm Solar Project | Open Energy Information

    Open Energy Info (EERE)

    Solar Project Facility Black River Farm Solar Project Sector Solar Facility Type Fixed Tilt Ground-Mount & Roof-Mount Owner EnXco Developer EnXco Energy Purchaser Black River Farm...

  1. Water telescope's first sky map shows flickering black holes

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Water telescope's first sky map shows flickering black holes Water telescope's first sky map shows flickering black holes The High Altitude Water Cherenkov observatory has released its first map of the sky, including the first measurements of how often black holes flicker on and off. It has also caught pulsars, supernova remnants, and other bizarre cosmic beasts. April 24, 2016 Water telescope's first sky map shows flickering black holes Three new sources of gamma rays spotted by HAWC. Credit:

  2. Gravitational waves found, black-hole models led the way

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Gravitational waves found, black-hole models led the way Gravitational waves found, black-hole models led the way Gravitational waves were predicted by Einstein's theory of general relativity in 1916, and now, almost exactly 100 years later, the faint ripples across space-time have been found. February 11, 2016 A simulation of two merging black holes, creating gravitational waves. Photo courtesy of LIGO. A simulation of two merging black holes, creating gravitational waves. Photo courtesy of

  3. Modified carbon black materials for lithium-ion batteries

    DOE Patents [OSTI]

    Kostecki, Robert; Richardson, Thomas; Boesenberg, Ulrike; Pollak, Elad; Lux, Simon

    2016-06-14

    A lithium (Li) ion battery comprising a cathode, a separator, an organic electrolyte, an anode, and a carbon black conductive additive, wherein the carbon black has been heated treated in a CO.sub.2 gas environment at a temperature range of between 875-925 degrees Celsius for a time range of between 50 to 70 minutes to oxidize the carbon black and reduce an electrochemical reactivity of the carbon black towards the organic electrolyte.

  4. Semiclassical S-matrix for black holes

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Bezrukov, Fedor; Levkov, Dmitry; Sibiryakov, Sergey

    2015-12-01

    In this study, we propose a semiclassical method to calculate S-matrix elements for two-stage gravitational transitions involving matter collapse into a black hole and evaporation of the latter. The method consistently incorporates back-reaction of the collapsing and emitted quanta on the metric. We illustrate the method in several toy models describing spherical self-gravitating shells in asymptotically flat and AdS space-times. We find that electrically neutral shells reflect via the above collapse-evaporation process with probability exp(–B), where B is the Bekenstein-Hawking entropy of the intermediate black hole. This is consistent with interpretation of exp(B) as the number of black hole states.more » The same expression for the probability is obtained in the case of charged shells if one takes into account instability of the Cauchy horizon of the intermediate Reissner-Nordström black hole. As a result, our semiclassical method opens a new systematic approach to the gravitational S-matrix in the non-perturbative regime.« less

  5. SLIM DISKS AROUND KERR BLACK HOLES REVISITED

    SciTech Connect (OSTI)

    Sadowski, Aleksander

    2009-08-01

    We investigate stationary slim accretion disks around Kerr black holes. We construct a new numerical method based on the relaxation technique. We systematically cover the whole parameter space relevant to stellar mass X-ray binaries. We also notice some non-monotonic features in the disk structure, overlooked in previous studies.

  6. Bubbling supertubes and foaming black holes

    SciTech Connect (OSTI)

    Bena, Iosif; Warner, Nicholas P.

    2006-09-15

    We construct smooth BPS three-charge geometries that resolve the zero-entropy singularity of the U(1)xU(1) invariant black ring. This singularity is resolved by a geometric transition that results in geometries without any branes sources or singularities but with nontrivial topology. These geometries are both ground states of the black ring, and nontrivial microstates of the D1-D5-P system. We also find the form of the geometries that result from the geometric transition of N zero-entropy black rings, and argue that, in general, such geometries give a very large number of smooth bound-state three-charge solutions, parametrized by 6N functions. The generic microstate solution is specified by a four-dimensional hyper-Kaehler geometry of a certain signature, and contains a 'foam' of nontrivial two-spheres. We conjecture that these geometries will account for a significant part of the entropy of the D1-D5-P black hole, and that Mathur's conjecture might reduce to counting certain hyper-Kaehler manifolds.

  7. T-534: Vulnerability in the PDF distiller of the BlackBerry Attachment Service for the BlackBerry Enterprise Server

    Broader source: Energy.gov [DOE]

    BlackBerry advisory describes a security issue that the BlackBerry Attachment Service component of the BlackBerry Enterprise Server is susceptible to. The issue relates to a known vulnerability in the PDF distiller component of the BlackBerry Attachment Service that affects how the BlackBerry Attachment Service processes PDF files.

  8. Trumpet-puncture initial data for black holes

    SciTech Connect (OSTI)

    Immerman, Jason D.; Baumgarte, Thomas W.

    2009-09-15

    We propose a new approach, based on the puncture method, to construct black hole initial data in the so-called trumpet geometry, i.e. on slices that asymptote to a limiting surface of nonzero areal radius. Our approach is easy to implement numerically and, at least for nonspinning black holes, does not require any internal boundary conditions. We present numerical results, obtained with a uniform-grid finite-difference code, for boosted black holes and binary black holes. We also comment on generalizations of this method for spinning black holes.

  9. Quasi-black holes: Definition and general properties

    SciTech Connect (OSTI)

    Lemos, Jose P. S.; Zaslavskii, Oleg B.

    2007-10-15

    Objects that are on the verge of being extremal black holes but actually are distinct in many ways are called quasi-black holes. Quasi-black holes are defined here and treated in a unified way by displaying their properties. Their main properties are as follows: (i) there are infinite redshift whole regions (ii) the spacetimes exhibit degenerate, almost singular, features but their curvature invariants remain perfectly regular everywhere (iii) in the limit under discussion, outer and inner regions become mutually impenetrable and disjoint, although, in contrast to the usual black holes, this separation is of a dynamical nature, rather than purely causal, and (iv) for external faraway observers the spacetime is virtually indistinguishable from that of extremal black holes. In addition, we show that quasi-black holes must be extremal. Connections with black hole and wormhole physics are also drawn.

  10. Pitch-angle diffusion of electrons through growing and propagating along a magnetic field electromagnetic wave in Earth's radiation belts

    SciTech Connect (OSTI)

    Choi, C.-R. Dokgo, K.; Min, K.-W.; Woo, M.-H.; Choi, E.-J.; Hwang, J.; Park, Y.-D.; Lee, D.-Y.

    2015-06-15

    The diffusion of electrons via a linearly polarized, growing electromagnetic (EM) wave propagating along a uniform magnetic field is investigated. The diffusion of electrons that interact with the growing EM wave is investigated through the autocorrelation function of the parallel electron acceleration in several tens of electron gyration timescales, which is a relatively short time compared with the bounce time of electrons between two mirror points in Earth's radiation belts. Furthermore, the pitch-angle diffusion coefficient is derived for the resonant and non-resonant electrons, and the effect of the wave growth on the electron diffusion is discussed. The results can be applied to other problems related to local acceleration or the heating of electrons in space plasmas, such as in the radiation belts.

  11. Astrophysical black holes in screened modified gravity

    SciTech Connect (OSTI)

    Davis, Anne-Christine; Jha, Rahul; Muir, Jessica; Gregory, Ruth E-mail: r.a.w.gregory@durham.ac.uk E-mail: jlmuir@umich.edu

    2014-08-01

    Chameleon, environmentally dependent dilaton, and symmetron gravity are three models of modified gravity in which the effects of the additional scalar degree of freedom are screened in dense environments. They have been extensively studied in laboratory, cosmological, and astrophysical contexts. In this paper, we present a preliminary investigation into whether additional constraints can be provided by studying these scalar fields around black holes. By looking at the properties of a static, spherically symmetric black hole, we find that the presence of a non-uniform matter distribution induces a non-constant scalar profile in chameleon and dilaton, but not necessarily symmetron gravity. An order of magnitude estimate shows that the effects of these profiles on in-falling test particles will be sub-leading compared to gravitational waves and hence observationally challenging to detect.

  12. Hanford Site Black-tailed Jackrabbit

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    10 Revision 0 Hanford Site Black-tailed Jackrabbit Monitoring Report for Fiscal Year 2013 Prepared for the U.S. Department of Energy Assistant Secretary for Environmental Management Contractor for the U.S. Department of Energy under Contract DE-AC06-09RL14728 P.O. Box 650 Richland, Washington 99352 Approved for Public Release Further Dissemination Unlimited HNF- 56710 Revision 0 TRADEMARK DISCLAIMER Reference herein to any specific commercial product, process, or service by trade name,

  13. Gold deposits in the late Archaean Nzega-Igunga greenstone belt, central plateau of tanzania

    SciTech Connect (OSTI)

    Feiss, P.G.; Siyomana, S.

    1985-01-01

    2.2 m oz of gold have been produced, since 1935, from late Archaean (2480-2740 Ma) greenstone belts of the Central Plateau, Tanzania. North and east of Nzega (4/sup 0/12'S, 3/sup 0/11'E), 18% of the exposed basement, mainly Dodoman schists and granites, consists of metavolcanics and metasediments of the Nyanzian and Kavirondian Series. Four styles of mineralization are observed. 1. Stratabound quartz-gold veins with minor sulfides. Host rocks are quartz porphyry, banded iron formation (BIF), magnetite quartzite, and dense, cherty jasperite at the Sekenke and Canuck mines. The Canuck veins are on strike from BIF's in quartz-eye porphyry of the Igusule Hills. 2. Stratabound, disseminated gold in coarse-grained, crowded feldspar porphyry with lithic fragments and minor pyrite. At Bulangamilwa, the porphyry is conformable with Nyanzian-aged submarine (.) greenstone, volcanic sediment, felsic volcanics, and sericite phyllite. The deposits are on strike with BIF of the Wella Hills, which contains massive sulfide with up to 15% Pb+Zn. 3. Disseminated gold in quartz-albite metasomes in Nyanzian greenstones. At Kirondatal, alteration is associated with alaskites and feldspar porphyry dikes traceable several hundred meters into post-Dodoman diorite porphyry. Gold is with pyrite, arsenopyrite, pyrrhotite, minor chalcopyrite, and sphalerite as well as tourmalinite and silica-cemented breccias. 4. Basal Kavirondian placers in metaconglomerates containing cobbles and boulders of Dodoman and Nyanzian rocks several hundred meters up-section from the stratabound, disseminated mineralization at Bulangamilwa.

  14. A long-lived relativistic electron storage ring embedded in Earth's Outer Van Allen belt

    SciTech Connect (OSTI)

    Baker, D. N.; Kanekal, S. G.; Hoxie, V. C.; Henderson, M. G.; Li, X.; Spence, H. E.; Elkington, S. R.; Friedel, R. H. W.; Goldstein, J.; Hudson, M. K.; Reeves, G. D.; Thorne, R. M.; Kletzing, C. A.; Claudepierre, S. G.

    2013-02-28

    Since their discovery over 50 years ago, the Earth’s Van Allen radiation belts are thought to consist of two distinct zones of trapped, highly energetic charged particles. The outer zone is comprised predominantly of mega-electron volt (MeV) electrons that wax and wane in intensity on time scales ranging from hours to days depending primarily on external forcing by the solar wind. Thus, the spatially separated inner zone is comprised of commingled high-energy electrons and very energetic positive ions (mostly protons), the latter being stable in intensity levels over years to decades. In situ energy-specific and temporally resolved spacecraft observations reveal an isolated third ring, or torus, of high-energy (E > 2 MeV) electrons that formed on 2 September 2012 and persisted largely unchanged in the geocentric radial range of 3.0 to ~3.5 Earth radii for over four weeks before being disrupted (and virtually annihilated) by a powerful interplanetary shock wave passage.

  15. Wave-driven butterfly distribution of Van Allen belt relativistic electrons

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Xiao, Fuliang; Yang, Chang; Su, Zhenpeng; Zhou, Qinghua; He, Zhaoguo; He, Yihua; Baker, D. N.; Spence, H. E.; Funsten, H. O.; Blake, J. B.

    2015-10-05

    Van Allen radiation belts consist of relativistic electrons trapped by Earth's magnetic field. Trapped electrons often drift azimuthally around Earth and display a butterfly pitch angle distribution of a minimum at 90° further out than geostationary orbit. This is usually attributed to drift shell splitting resulting from day–night asymmetry in Earth’s magnetic field. However, direct observation of a butterfly distribution well inside of geostationary orbit and the origin of this phenomenon have not been provided so far. Here we report high-resolution observation that a unusual butterfly pitch angle distribution of relativistic electrons occurred within 5 Earth radii during the 28more » June 2013 geomagnetic storm. In conclusion, simulation results show that combined acceleration by chorus and magnetosonic waves can successfully explain the electron flux evolution both in the energy and butterfly pitch angle distribution. Finally, the current provides a great support for the mechanism of wave-driven butterfly distribution of relativistic electrons.« less

  16. A long-lived relativistic electron storage ring embedded in Earth's Outer Van Allen belt

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Baker, D. N.; Kanekal, S. G.; Hoxie, V. C.; Henderson, M. G.; Li, X.; Spence, H. E.; Elkington, S. R.; Friedel, R. H. W.; Goldstein, J.; Hudson, M. K.; et al

    2013-02-28

    Since their discovery over 50 years ago, the Earth’s Van Allen radiation belts are thought to consist of two distinct zones of trapped, highly energetic charged particles. The outer zone is comprised predominantly of mega-electron volt (MeV) electrons that wax and wane in intensity on time scales ranging from hours to days depending primarily on external forcing by the solar wind. Thus, the spatially separated inner zone is comprised of commingled high-energy electrons and very energetic positive ions (mostly protons), the latter being stable in intensity levels over years to decades. In situ energy-specific and temporally resolved spacecraft observations revealmore » an isolated third ring, or torus, of high-energy (E > 2 MeV) electrons that formed on 2 September 2012 and persisted largely unchanged in the geocentric radial range of 3.0 to ~3.5 Earth radii for over four weeks before being disrupted (and virtually annihilated) by a powerful interplanetary shock wave passage.« less

  17. Integration of upgrading in the production of extra heavy crudes from the orinoco belt

    SciTech Connect (OSTI)

    Solari, R.B.; Marzin, R.; Soler, L.

    1996-12-31

    Four heavy oil upgrading joint ventures with major oil players are currently being developed by Petroleos de Venezuela, S.A. (PDVSA) affiliates. Their objective is to build integrated production-upgrading complexes to transform the low quality heavy oil from the Orinoco Belt into valuable synthetic crude oil (SCO). One of this joint ventures, a partnership between Corpoven, S.A. and ARCO International Oil and Gas Co., thoroughly evaluated the new HDH{trademark} hydroprocessing technology of Intevep, S.A. as an option to upgrade 99 API Hamaca extraheavy crude. This paper summarizes the characteristics and economics of an integrated worldscale production-upgrading complex based on the HDH{trademark} technology as compared to a similar complex based on the well known delayed coking process. It concludes that whenever high liquid yields and/or feedstock cost drives the process economics, HDH{trademark} can compite advantageously with these more conventional technologies. At present, Maraven, S.A., another PDVSA affiliate, is developing the first HDH{trademark} commercial unit, to be built in its Cardon Refinery. It is anticipated that the 100 m{sup 3}/h unit will be in operation by 1998, allowing the demonstration of the process, as well as further optimizations of the scheme, thereby improving its economic competitiveness. 2 refs., 3 figs., 1 tab.

  18. Hydrocarbon exploration through remote sensing and field work in the onshore Eastern Papuan Fold Belt, Gulf province, Papua New Guinea

    SciTech Connect (OSTI)

    Dekker, F.; Balkwill, H.; Slater, A. ); Herner, R. ); Kampschuur, W. )

    1990-05-01

    Over the years several types of remote sensing surveys have been acquired of the Eastern Papuan Fold Belt, in the Gulf Province of Papua New Guinea. These include aerial photographs, Landsat Multispectral Scanner (MSS), and Synthetic Aperture Radar (SAR). Each has been used by Petro-Canada Inc. for interpreting the geologic structure and stratigraphy of onshore hydrocarbon prospects. Analysis of available remotely sensed imagery reveals greater structural complexity than is shown on published geologic maps. Foremost among the images is SAR because of its low, artificial sun angle. Hence, a comprehensive view of the area has been acquired revealing many structural elements previously not appreciated. A distinct difference in structural style is found between the northern and southern segment of the Eastern Papuan fold belt in the study area. The northern segment shows discontinuous, open folds with widely separated anticlines set in featureless valleys. The southern segment is tightly folded, possessing few anticlines and synclines clearly recognizable on the imagery. However, structural components can be traced easily for tens of miles. Recent field work supports an SAR structural interpretation suggesting most, if not all, anticlines in the northern segment are overturned. The combination of remote sensing and field work proved invaluable in understanding the fold belt tectonics and has aided considerably in the selection of drilling locations.

  19. Magnetostratigraphic constraints on the development of paired fold-thrust belts/foreland basins in the Argentine Andes

    SciTech Connect (OSTI)

    Reynolds, J.H. ); Damanti, J.F. ); Jordan, T.E. )

    1991-03-01

    Development of a paired fold thrust-thrust belt/foreland basin is correlated to the flattening of the subducting Nazca plate between 28-33{degree}S. Magnetostratigraphic studies in neogene basin-filling continental strata determine local basin subsidence rates and provide relatively precise chronostratigraphic correlation between different depositional environments. The data demonstrate that most existing lithostratigraphic units are diachronous and require new tectonic interpretations. Increases in sediment accumulation rates closely correspond to changes in provenance and indicate that the Frontal Cordillera, on the Chile-Argentina border was a positive topographic province by 18 Ma. The Precordillera evolved from {approx}16 Ma to the present as thrusting migrated from west to east. Published ages from intercalated airfall tuffs constrain some sedimentary sections in the eastern Sierras Pampeanas where the earliest uplift occurred since 10 Ma. The youngest uplifts are on the west side close to continuing thrusting in the Precordillera. Not all fold-thrust belt/foreland basin pairs are associated with flat subduction, suggesting that tectonic controls exceeding the scale of individual plate segments may be important. The hydrocarbon-producing Subandean fold-thrust belt/foreland basin, located in the area of 'steep' subduction that underlies northern Argentina and Bolivia (18-24{degree}S), is also believed to have evolved since middle Miocene time. Recently initiated magnetostratigraphic studies in the Subandean foreland basin will attempt to temporally constrain the Neogene tectonic evolution for comparison with the southern region.

  20. Highly relativistic radiation belt electron acceleration, transport, and loss: Large solar storm events of March and June 2015

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Baker, Daniel N.; Jaynes, A. N.; Kanekal, S. G.; Foster, J. C.; Erickson, P. J.; Fennell, J. F.; Blake, J. B.; Zhao, H.; Li, X.; Elkington, S. R.; et al

    2016-07-26

    Two of the largest geomagnetic storms of the last decade were witnessed in 2015. On 17 March 2015, a coronal mass ejection-driven event occurred with a Dst (storm time ring current index) value reaching –223 nT. On 22 June 2015 another strong storm (Dst reaching –204 nT) was recorded. These two storms each produced almost total loss of radiation belt high-energy (E ≳ 1 MeV) electron fluxes. Following the dropouts of radiation belt fluxes there were complex and rather remarkable recoveries of the electrons extending up to nearly 10 MeV in kinetic energy. The energized outer zone electrons showed amore » rich variety of pitch angle features including strong “butterfly” distributions with deep minima in flux at α = 90°. However, despite strong driving of outer zone earthward radial diffusion in these storms, the previously reported “impenetrable barrier” at L ≈ 2.8 was pushed inward, but not significantly breached, and no E ≳ 2.0 MeV electrons were seen to pass through the radiation belt slot region to reach the inner Van Allen zone. Altogether, these intense storms show a wealth of novel features of acceleration, transport, and loss that are demonstrated in the present detailed analysis.« less

  1. Twin-belt continuous caster with containment and cooling of the exiting cast product for enabling high-speed casting of molten-center product

    DOE Patents [OSTI]

    Dykes, Charles D.; Daniel, Sabah S.; Wood, J. F. Barry

    1990-02-20

    In continuously casting molten metal into cast product by a twin-belt machine, it is desirable to achieve dramatic increases in speed (linear feet per minute) at which cast product exits the machine, particularly in installations where steel cast product is intended to feed a downstream regular rolling mill (as distinct from a planetary mill) operating in tandem with the twin-belt caster. Such high-speed casting produces product with a relatively thin shell and molten interior, and the shell tends to bulge outwardly due to metallostatic head pressure of the molten center. A number of cooperative features enable high-speed, twin-belt casting: (1) Each casting belt is slidably supported adjacent to the caster exit pulley for bulge control and enhanced cooling of cast product. (2) Lateral skew steering of each belt provides an effective increase in moving mold length plus a continuity of heat transfer not obtained with prior art belt steering apparatus. (3) The exiting slab is contained and supported downstream from the casting machine to prevent bulging of the shell of the cast product, and (4) spray cooling is incorporated in the exit containment apparatus for secondary cooling of cast product.

  2. Phenomenological loop quantum geometry of the Schwarzschild black hole

    SciTech Connect (OSTI)

    Chiou, D.-W.

    2008-09-15

    The interior of a Schwarzschild black hole is investigated at the level of phenomenological dynamics with the discreteness corrections of loop quantum geometry implemented in two different improved quantization schemes. In one scheme, the classical black hole singularity is resolved by the quantum bounce, which bridges the black hole interior with a white hole interior. In the other scheme, the classical singularity is resolved and the event horizon is also diffused by the quantum bounce. Jumping over the quantum bounce, the black hole gives birth to a baby black hole with a much smaller mass. This lineage continues as each classical black hole brings forth its own descendant in the consecutive classical cycle, giving the whole extended spacetime fractal structure, until the solution eventually descends into the deep Planck regime, signaling a breakdown of the semiclassical description. The issues of scaling symmetry and no-hair theorem are also discussed.

  3. Multiscalar black holes with contingent primary hair: Mechanics and stability

    SciTech Connect (OSTI)

    Mignemi, Salvatore; Wiltshire, David L.

    2004-12-15

    We generalize a class of magnetically charged black holes nonminimally coupled to two scalar fields previously found by one of us to the case of multiple scalar fields. The black holes possess a novel type of primary scalar hair, which we call a contingent primary hair: although the solutions possess degrees of freedom which are not completely determined by the other charges of the theory, the charges necessarily vanish in the absence of the magnetic monopole. Only one constraint relates the black hole mass to the magnetic charge and scalar charges of the theory. We obtain a Smarr-type thermodynamic relation, and the first law of black hole thermodynamics for the system. We further explicitly show in the two-scalar-field case that, contrary to the case of many other hairy black holes, the black hole solutions are stable to radial perturbations.

  4. The Black Mesa coal/water slurry pipeline system

    SciTech Connect (OSTI)

    Brolick, H.J.

    1994-12-31

    The Black Mesa Pipeline is a 273 mile (439 km) long, 18-inch (457 mm) coal/water slurry pipeline, originating on the Black Mesa in the Northeastern part of Arizona, USA. The system delivers coal from the Peabody Coal Company`s Black Mesa open pit mine to the Mohave Generating Station which is a 1580 mw steam powered electric generating plant located in Laughlin, Nevada.

  5. Fossil Energy Acting Assistant Secretary Recognized at Black Engineer of

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    the Year Awards | Department of Energy Fossil Energy Acting Assistant Secretary Recognized at Black Engineer of the Year Awards Fossil Energy Acting Assistant Secretary Recognized at Black Engineer of the Year Awards February 19, 2013 - 8:54am Addthis Director Dot Harris presents Chris Smith, Principal Deputy Assistant Secretary and Acting Assistant Secretary of Fossil Energy, with a professional achievement award at the Black Engineer of the Year Awards conference this February. Photo

  6. Searching for tiny black holes during cold fusion

    SciTech Connect (OSTI)

    Matsumoto, T. . Dept. of Nuclear Engineering)

    1992-09-01

    A previous technical note suggests that cold fusion is a small-scale simulation of events that occur in cold stars far-away in the universe. Therefore, it is expected that tiny black holes might be produced during cold fusion. In this paper, a search for tiny black holes whose traces might have been recorded on nuclear emulsions is described. Several traces suggesting the production and evaporation of tiny black holes have been successfully observed.

  7. PHYSICAL PROPERTIES OF MAIN-BELT COMET 176P/LINEAR

    SciTech Connect (OSTI)

    Hsieh, Henry H.; Ishiguro, Masateru; Lacerda, Pedro; Jewitt, David E-mail: p.lacerda@qub.ac.uk E-mail: jewitt@ucla.edu

    2011-07-15

    We present a physical characterization of comet 176P/LINEAR, the third discovered member of the new class of main-belt comets, which exhibit cometary activity but are dynamically indistinguishable from main-belt asteroids. Observations show the object exhibiting a fan-shaped tail for at least one month in late 2005, but then becoming inactive in early 2006. During this active period, we measure broadband colors of B - V = 0.63 {+-} 0.02, V - R = 0.35 {+-} 0.02, and R - I = 0.31 {+-} 0.04. Using data from when the object was observed to be inactive, we derive best-fit IAU phase function parameters of H = 15.10 {+-} 0.05 mag and G = 0.15 {+-} 0.10, and best-fit linear phase function parameters of m(1, 1, 0) = 15.35 {+-} 0.05 mag and {beta} = 0.038 {+-} 0.005 mag deg{sup -1}. From this baseline phase function, we find that 176P exhibits a mean photometric excess of {approx}30% during its active period, implying an approximate total coma dust mass of M{sub d} {approx} (7.2 {+-} 3.6) x 10{sup 4} kg. From inactive data obtained in early 2007, we find a rotation period of P{sub rot} = 22.23 {+-} 0.01 hr and a peak-to-trough photometric range of {Delta}m {approx} 0.7 mag. Phasing our photometric data from 176P's 2005 active period to this rotation period, we find that the nucleus exhibits a significantly smaller photometric range than in 2007 that cannot be accounted for by coma damping effects, and as such, are attributed by us to viewing geometry effects. A detailed analysis of these geometric effects showed that 176P is likely to be a highly elongated object with an axis ratio of 1.8 < b/a < 2.1, an orbital obliquity of {epsilon} {approx} 60{sup 0}, and a solstice position at a true anomaly of {nu}{sub o} = 20{sup 0} {+-} 20{sup 0}. Numerical modeling of 176P's dust emission found that its activity can only be reproduced by asymmetric dust emission, such as a cometary jet. We find plausible fits to our observations using models assuming {approx}10 {mu}m dust particles

  8. Funds Awarded to Historically Black Colleges and Universities...

    Broader source: Energy.gov (indexed) [DOE]

    Research by Historically Black Colleges and Universities and Other Minority Institutions (HBCUOMI), recently announced awards to institutions under the HBCUOMI designation. ...

  9. Savannah River National Laboratory Meets with Historically Black...

    Energy Savers [EERE]

    Last week, student and faculty leaders at seven Historically Black Colleges and Universities (HBCUs) spent the day at the Center for Hydrogen Research at Savannah River National ...

  10. Black Hawk County, Iowa: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Solutions Places in Black Hawk County, Iowa Cedar Falls, Iowa Dunkerton, Iowa Elk Run Heights, Iowa Evansdale, Iowa Gilbertville, Iowa Hudson, Iowa Janesville, Iowa Jesup,...

  11. Variation of the radiative properties during black carbon aging...

    Office of Scientific and Technical Information (OSTI)

    A theoretical black carbon (BC) aging model is developed to account for three typical evolution stages, namely, freshly emitted aggregates, coated BC by soluble material, and BC ...

  12. Black Hills Energy (Gas) - Commercial Energy Efficiency Rebate...

    Broader source: Energy.gov (indexed) [DOE]

    sq ft. Infiltration Control: 70% of installed cost Doors: 25 or 50 Pool Cover: 250 Spa Cover: 50 Summary Black Hills Energy offers commercial and industrial customers...

  13. BlackLight Power Inc | Open Energy Information

    Open Energy Info (EERE)

    Name: BlackLight Power Inc Place: Cranbury, New Jersey Zip: 8512 Sector: Hydro, Hydrogen Product: Researching a means of producing energy by catalysing the reaction of...

  14. Black Forest, Colorado: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Black Forest, Colorado: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 39.0130484, -104.7008083 Show Map Loading map... "minzoom":false,"mappi...

  15. Black Hole Remnants in the Early Universe (Journal Article) ...

    Office of Scientific and Technical Information (OSTI)

    Title: Black Hole Remnants in the Early Universe Authors: Scardigli, Fabio ; Gruber, Christine ; Taiwan, Natl. Taiwan U. ; Chen, Pisin ; Taiwan, Natl. Taiwan U. KIPAC, Menlo ...

  16. Black Hills Energy (Electric)- Commercial Energy Efficiency Program

    Broader source: Energy.gov [DOE]

    Black Hills Energy also offers the custom rebate program to commercial and industrial customers for projects that reduce energy usage. Eligible projects include chillers, unitary HVAC equipment,...

  17. SEARCH FOR SUPERMASSIVE BLACK HOLE BINARIES IN THE SLOAN DIGITAL...

    Office of Scientific and Technical Information (OSTI)

    THE SLOAN DIGITAL SKY SURVEY SPECTROSCOPIC SAMPLE Citation Details In-Document Search Title: SEARCH FOR SUPERMASSIVE BLACK HOLE BINARIES IN THE SLOAN DIGITAL SKY SURVEY ...

  18. Will new horizons see dust clumps in the Edgeworth-Kuiper Belt?

    SciTech Connect (OSTI)

    Vitense, Christian; Krivov, Alexander V.; Lhne, Torsten

    2014-06-01

    Debris disks are thought to be sculptured by neighboring planets. The same is true for the Edgeworth-Kuiper debris disk, yet no direct observational evidence for signatures of giant planets in the Kuiper Belt dust distribution has been found so far. Here we model the dust distribution in the outer solar system to reproduce the dust impact rates onto the dust detector on board the New Horizons spacecraft measured so far and to predict the rates during the Neptune orbit traverse. To this end, we take a realistic distribution of trans-Neptunian objects to launch a sufficient number of dust grains of different sizes and follow their orbits by including radiation pressure, Poynting-Robertson and stellar wind drag, as well as the perturbations of four giant planets. In a subsequent statistical analysis, we calculate number densities and lifetimes of the dust grains in order to simulate a collisional cascade. In contrast to the previous work, our model not only considers collisional elimination of particles but also includes production of finer debris. We find that particles captured in the 3:2 resonance with Neptune build clumps that are not removed by collisions, because the depleting effect of collisions is counteracted by production of smaller fragments. Our model successfully reproduces the dust impact rates measured by New Horizons out to ?23 AU and predicts an increase of the impact rate of about a factor of two or three around the Neptune orbit crossing. This result is robust with respect to the variation of the vaguely known number of dust-producing scattered disk objects, collisional outcomes, and the dust properties.

  19. Hubble space telescope investigation of main-belt comet 133P/Elst-Pizarro

    SciTech Connect (OSTI)

    Jewitt, David; Ishiguro, Masateru; Weaver, Harold; Agarwal, Jessica; Mutchler, Max; Larson, Steven

    2014-05-01

    We report new observations of the prototype main-belt comet (active asteroid) 133P/Elst-Pizarro taken at high angular resolution using the Hubble Space Telescope. The object has three main components: (1) a point-like nucleus; (2) a long, narrow antisolar dust tail; and (3) a short, sunward anti-tail. There is no resolved coma. The nucleus has a mean absolute magnitude H{sub V} = 15.70 0.10 and a light curve range ?V = 0.42 mag, the latter corresponding to projected dimensions 3.6 5.4 km (axis ratio 1.5:1) at the previously measured geometric albedo of 0.05 0.02. We explored a range of continuous and impulsive emission models to simultaneously fit the measured surface brightness profile, width, and position angle of the antisolar tail. Preferred fits invoke protracted emission, over a period of 150 days or less, of dust grains following a differential power-law size distribution with index 3.25 ?q ? 3.5 and with a wide range of sizes. Ultra-low surface brightness dust projected in the sunward direction is a remnant from emission activity occurring in previous orbits, and consists of the largest (?cm-sized) particles. Ejection velocities of one-micron-sized particles are comparable to the ?1.8 m s{sup 1} gravitational escape speed of the nucleus, while larger particles are released at speeds less than the gravitational escape velocity. The observations are consistent with, but do not prove, a hybrid hypothesis in which mass loss is driven by gas drag from the sublimation of near-surface water ice, but escape is aided by centripetal acceleration from the rotation of the elongated nucleus. No plausible alternative hypothesis has been identified.

  20. Crustal structure of mountain belts and basins: Industry and academic collaboration at Cornell

    SciTech Connect (OSTI)

    Allmendinger, R.; Barazangi, M.; Brown, L.

    1995-08-01

    Interdisciplinary investigations of the large-scale structure and evolution of key basins and orogenic belts around the world are the focal point of academic-industry interaction at Cornell. Ongoing and new initiatives with significant industry involvement include: Project INDEPTH (Interdisciplinary Deep Profiling of Tibet and the Himalayas), a multinational effort to delineate deep structure across the type example of active continent-continent collision. 300 km of deep reflection profiling was collected across the Himalaya: and southern Tibet Plateau in 1992 and 1994. CAP (Cornell Andes Project), a long-standing interdisciplinary effort to understand the structure and evolution of the Andes, with a focus on Argentina, Chile and Bolivia. A deep reflection profile is tentatively planned for 1997. Intra-plate Orogeny in the Middle East and North Africa is the focus of multidisciplinary regional syntheses of existing seismic reflection and other databases in Syria (Palmyrides)and Morocco (Atlas), with an emphasis on reactivation and inversion tectonics. Project URSEIS (Urals Reflection Seismic Experiment and Integrated Studies) is a collaboration with EUROPROBE to collect 500 km of vibroseis and dynamite deep reflection profiling across the southern Urals in 1995. Project CRATON, an element in COCORP`s systematic exploration of the continental US, is a nascent multi-disciplinary effort to understand the buried craton of the central US and the basins built upon it. Global Basins Research Network (GBRN) is a diversified observational and computational effort to image and model the movement of pore fluids in detail and on a regional scale for a producing oil structure in the Gulf of Mexico.

  1. Predicting methane accumulations generated from humic Carboniferous coals in the Donbas fold belt (Ukraine)

    SciTech Connect (OSTI)

    Alsaab, D.; Elie, M.; Izart, A.; Sachsenhofer, R.F.; Privalov, V.A.

    2008-08-15

    The numerical modeling of the Ukrainian part of the Donbas fold belt indicates that the coalification pattern was controlled mainly by the maximum burial depth of coal seams and the heat flow (HF) (40-75 mW/m{sup 2}) during the Permian. The coalification pattern was overprinted by magmatic events during the Late Permian in the south syncline (150 mW/m{sup 2}) and during the Permian-Triassic in the north of the Krasnoarmeisk region (120 mW/m{sup 2}). The coalification pattern shows a strong increase in vitrinite reflectance values toward the east and southeastern parts of the study area likely caused by (1) an eastward increase in burial depth, (2) a probable eastward increase in HF, and, (3) probable magmatic activity. An increase in total erosion toward the eastern and southeastern parts was also observed with a maximum erosional amount of approximately 8 km (5 mi) in the southeastern part of the study area. The basin modeling of this area predicts that the main phase of hydrocarbon generation occurred during the Carboniferous-Early Permian subsidence. The magmatic events that occurred during the Permian-Triassic caused renewed pulses of hydrocarbon generation. A large amount of the generated hydrocarbons was lost to the surface because of a lack of seals. However, the numerical simulation predicts accumulations of about 2 tcf (57 billion m{sup 3}) of methane generated from Carboniferous coals in the south and main synclines, where Lower Permian seal rocks are preserved. Finally, this study provides data on methane resources along the northern flank

  2. Acoustic analogues of black hole singularities

    SciTech Connect (OSTI)

    Cadoni, Mariano; Mignemi, Salvatore

    2005-10-15

    We search for acoustic analogues of a spherical symmetric black hole with a pointlike source. We show that the gravitational system has a dynamical counterpart in the constrained, steady motion of a fluid with a planar source. The equations governing the dynamics of the gravitational system can be exactly mapped in those governing the motion of the fluid. The different meaning that singularities and sources have in fluid dynamics and in general relativity is also discussed. Whereas in the latter a pointlike source is always associated with a (curvature) singularity in the former the presence of sources does not necessarily imply divergences of the fields.

  3. T-579: BlackBerry Device Software Bug in WebKit Lets Remote Users...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    or instant messages. BlackBerry has described a workaround (disabling the use of JavaScript in the BlackBerry Browser) in their advisory. BlackBerry Device storage space...

  4. T-602: BlackBerry Enterprise Server Input Validation Flaw in...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    02: BlackBerry Enterprise Server Input Validation Flaw in BlackBerry Web Desktop Manager Permits Cross-Site Scripting Attacks T-602: BlackBerry Enterprise Server Input Validation...

  5. BLACK HOLE FORAGING: FEEDBACK DRIVES FEEDING

    SciTech Connect (OSTI)

    Dehnen, Walter; King, Andrew, E-mail: wd11@leicester.ac.uk, E-mail: ark@astro.le.ac.uk [Theoretical Astrophysics Group, University of Leicester, Leicester LE1 7RH (United Kingdom)] [Theoretical Astrophysics Group, University of Leicester, Leicester LE1 7RH (United Kingdom)

    2013-11-10

    We suggest a new picture of supermassive black hole (SMBH) growth in galaxy centers. Momentum-driven feedback from an accreting hole gives significant orbital energy, but little angular momentum to the surrounding gas. Once central accretion drops, the feedback weakens and swept-up gas falls back toward the SMBH on near-parabolic orbits. These intersect near the black hole with partially opposed specific angular momenta, causing further infall and ultimately the formation of a small-scale accretion disk. The feeding rates into the disk typically exceed Eddington by factors of a few, growing the hole on the Salpeter timescale and stimulating further feedback. Natural consequences of this picture include (1) the formation and maintenance of a roughly toroidal distribution of obscuring matter near the hole; (2) random orientations of successive accretion disk episodes; (3) the possibility of rapid SMBH growth; (4) tidal disruption of stars and close binaries formed from infalling gas, resulting in visible flares and ejection of hypervelocity stars; (5) super-solar abundances of the matter accreting on to the SMBH; and (6) a lower central dark-matter density, and hence annihilation signal, than adiabatic SMBH growth implies. We also suggest a simple subgrid recipe for implementing this process in numerical simulations.

  6. Black holes can have curly hair

    SciTech Connect (OSTI)

    Bronnikov, K. A.; Zaslavskii, O. B.

    2008-07-15

    We study equilibrium conditions between a static, spherically symmetric black hole and classical matter in terms of the radial pressure to density ratio p{sub r}/{rho}=w(u), where u is the radial coordinate. It is shown that such an equilibrium is possible in two cases: (i) the well-known case w{yields}-1 as u{yields}u{sub h} (the horizon), i.e., 'vacuum' matter, for which {rho}(u{sub h}) can be nonzero; (ii) w{yields}-1/(1+2k) and {rho}{approx}(u-u{sub h}){sup k} as u{yields}u{sub h}, where k>0 is a positive integer (w=-1/3 in the generic case k=1). A noninteracting mixture of these two kinds of matter can also exist. The whole reasoning is local, hence the results do not depend on any global or asymptotic conditions. They mean, in particular, that a static black hole cannot live inside a star with nonnegative pressure and density. As an example, an exact solution for an isotropic fluid with w=-1/3 (that is, a fluid of disordered cosmic strings), with or without vacuum matter, is presented.

  7. U-228: BlackBerry Tablet OS Flash Player Multiple Vulnerabilities...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Addthis PROBLEM: BlackBerry Tablet OS Flash Player Multiple Vulnerabilities PLATFORM: Adobe Flash Player versions included with BlackBerry PlayBook tablet software versions...

  8. Restoration of geological surface-UNFOLD method-a validation of complex structural mapping interpretation in the Andean Thrust Belt

    SciTech Connect (OSTI)

    Guillier, B. ); Oller, J.; Mendez, E.; Leconte, J.C.; Letouzey, J.; Specht, M.; Gratier, J.P.

    1993-02-01

    One of the most important problems in petroleum structural geology is dependable interpretation of structural maps obtained by seismic and sub-surface data. One method for validating the geometry of geological structures is the balancing cross-section technique which allows verification of cross-section geometry by a return to its initial horizontal state. However, this can not be used for of 3D halokinesis, shale tectonics, structures formed by polyphased noncoaxial tectonic events, or strike-slip and wrench faulting. An alternative approach is to test the restoration of folded and faulted surfaces to verify 3D structures by balancing geological surfaces represented by a structural map. This method tests the geometry of studied horizon and faults and is based upon the fact that, initially, actual folded/faulted structures were continuous at deposition. The balancing surface program, UNFOLD, restores the actual geological surface to its initial state. Misfits along faults implied poor structural map drawings or strong internal deformation of the geological level. By trial and error method, we returned to the initial data interpretation modifications. This method has been applied to 2D and 3D seismic structural interpretation in different structural styles, environments, rift zones, salt basins, wrench faulting, thrust belt,etc. Some applications to oil field structures in the Andean Thrust Belt have been done to check and validate the complex structural mapping interpretation.

  9. Nonuniform black strings in various dimensions

    SciTech Connect (OSTI)

    Sorkin, Evgeny

    2006-11-15

    The nonuniform black-strings branch, which emerges from the critical Gregory-Laflamme string, is numerically constructed in dimensions 6{<=}D{<=}11 and extended into the strongly nonlinear regime. All the solutions are more massive and less entropic than the marginal string. We find the asymptotic values of the mass, the entropy and other physical variables in the limit of large horizon deformations. By explicit metric comparison we verify that the local geometry around the waist of our most nonuniform solutions is conelike with less than 10% deviation. We find evidence that in this regime the characteristic length scale has a power-law dependence on a parameter along the branch of the solutions, and estimate the critical exponent.

  10. Modeling the black hole excision problem

    SciTech Connect (OSTI)

    Szilagyi, B.; Winicour, J.; Kreiss, H.-O.

    2005-05-15

    We analyze the excision strategy for simulating black holes. The problem is modeled by the propagation of quasilinear waves in a 1-dimensional spatial region with timelike outer boundary, spacelike inner boundary and a horizon in between. Proofs of well-posed evolution and boundary algorithms for a second differential order treatment of the system are given for the separate pieces underlying the finite-difference problem. These are implemented in a numerical code which gives accurate long term simulations of the quasilinear excision problem. Excitation of long wavelength exponential modes, which are latent in the problem, are suppressed using conservation laws for the discretized system. The techniques are designed to apply directly to recent codes for the Einstein equations based upon the harmonic formulation.

  11. Charged black holes in generalized teleparallel gravity

    SciTech Connect (OSTI)

    Rodrigues, M.E.; Houndjo, M.J.S.; Tossa, J.; Momeni, D.; Myrzakulov, R. E-mail: sthoundjo@yahoo.fr E-mail: d.momeni@yahoo.com

    2013-11-01

    In this paper we investigate charged static black holes in 4D for generalized teleparallel models of gravity, based on torsion as the geometric object for describing gravity according to the equivalence principle. As a motivated idea, we introduce a set of non-diagonal tetrads and derive the full system of non linear differential equations. We prove that the common Schwarzschild gauge is applicable only when we study linear f(T) case. We reobtain the Reissner-Nordstrom-de Sitter (or RN-AdS) solution for the linear case of f(T) and perform a parametric cosmological reconstruction for two nonlinear models. We also study in detail a type of the no-go theorem in the framework of this modified teleparallel gravity.

  12. Varying fine structure 'constant' and charged black holes

    SciTech Connect (OSTI)

    Bekenstein, Jacob D.; Schiffer, Marcelo

    2009-12-15

    Speculation that the fine-structure constant {alpha} varies in spacetime has a long history. We derive, in 4-D general relativity and in isotropic coordinates, the solution for a charged spherical black hole according to the framework for dynamical {alpha} J. D. Bekenstein, Phys. Rev. D 25, 1527 (1982).. This solution coincides with a previously known one-parameter extension of the dilatonic black hole family. Among the notable properties of varying-{alpha} charged black holes are adherence to a 'no hair' principle, the absence of the inner (Cauchy) horizon of the Reissner-Nordstroem black holes, the nonexistence of precisely extremal black holes, and the appearance of naked singularities in an analytic extension of the relevant metric. The exteriors of almost extremal electrically (magnetically) charged black holes have simple structures which makes their influence on applied magnetic (electric) fields transparent. We rederive the thermodynamic functions of the modified black holes; the otherwise difficult calculation of the electric potential is done by a shortcut. We confirm that variability of {alpha} in the wake of expansion of the universe does not threaten the generalized second law.

  13. Black phosphorus saturable absorber for ultrashort pulse generation

    SciTech Connect (OSTI)

    Sotor, J. Sobon, G.; Abramski, K. M.; Macherzynski, W.; Paletko, P.

    2015-08-03

    Low-dimensional materials, due to their unique and versatile properties, are very interesting for numerous applications in electronics and optoelectronics. Recently rediscovered black phosphorus, with a graphite-like layered structure, can be effectively exfoliated up to the single atomic layer called phosphorene. Contrary to graphene, it possesses a direct band gap controllable by the number of stacked atomic layers. For those reasons, black phosphorus is now intensively investigated and can complement or replace graphene in various photonics and electronics applications. Here, we demonstrate that black phosphorus can serve as a broadband saturable absorber and can be used for ultrashort optical pulse generation. The mechanically exfoliated ∼300 nm thick layers of black phosphorus were transferred onto the fiber core, and under pulsed excitation at 1560 nm wavelength, its transmission increases by 4.6%. We have demonstrated that the saturable absorption of black phosphorus is polarization sensitive. The fabricated device was used to mode-lock an Er-doped fiber laser. The generated optical solitons with the 10.2 nm bandwidth and 272 fs duration were centered at 1550 nm. The obtained results unambiguously show that black phosphorus can be effectively used for ultrashort pulse generation with performances similar or even better than currently used graphene or carbon nanotubes. This application of black phosphorus proves its great potential to future practical use in photonics.

  14. KCP's Carey honored as 2014 Black Achiever | National Nuclear Security

    National Nuclear Security Administration (NNSA)

    Administration | (NNSA) KCP's Carey honored as 2014 Black Achiever Monday, February 10, 2014 - 11:00am KCP's Carey honored as 2014 Black Achiever Anthony Carey is not just focused on developing the next generation of Test Systems for our nation's military; he's also focused on developing the next generation of young leaders. A Technical Manager for the Kansas City Plant, Anthony was honored Jan. 16 at the annual Black Achievers Society of Kansas City event for his leadership both in the

  15. ARM - Field Campaign - Black Carbon at the Mt. Bachelor Observatory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    govCampaignsBlack Carbon at the Mt. Bachelor Observatory Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Black Carbon at the Mt. Bachelor Observatory 2016.06.15 - 2016.10.01 Lead Scientist : Daniel Jaffe Abstract Black carbon (BC) is a key component in the earth system and a significant climate forcing agent. Observations at remote sites and in free-tropospheric air are extremely sparse. We propose to utilize one of the ARM SP2 (Single

  16. ARM - Field Campaign - Characterization of Black Carbon Mixing State

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    govCampaignsCharacterization of Black Carbon Mixing State Campaign Links Field Campaign Report ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Characterization of Black Carbon Mixing State 2012.11.01 - 2013.06.14 Lead Scientist : Arthur Sedlacek For data sets, see below. Abstract The objective of the proposed experiments was to characterize the mixing state of black carbon produced in biomass burning

  17. Paramont's Black Bear No. 4 mine does it right, again

    SciTech Connect (OSTI)

    Sanda, A.

    2007-07-15

    The Paramont Coal Company Virginia, LLC, a subsidiary of Alpha Natural Resources, recently won the '2007 overall award for excellence in mining and reclamation from the Virginia Division of Mined Land Reclamation and the Virginia Mining Association. Coal People Magazine recently visited Black Bear No. 4 mine where a settling pond was being removed and stream bed placed to drain the area, part of the 451-acre award winning reclamation project. The article recounts discussions with mining engineers about the company's operations with emphasis on the Black Bear No. 4 mine. Black Bear No. 1 mine won five state and national awards last year for conservation and land management practices. 8 photos.

  18. Back reaction on a Reissner-Nordstro''m black hole

    SciTech Connect (OSTI)

    Wang, Bobo; Huang, Chao-guang

    2001-06-15

    The perturbed (''dressed'') metric of the conformally invariant scalar field in a Reissner-Nordstroem (RN) black hole is given by solving the semiclassical Einstein and Maxwell equations according to York's back-reaction approach. Some properties of the ''dressed'' black hole are obtained, such as its ''dressed'' mass, the location of the event horizon, and its surface gravity. It will also be found that the hypersurfaces of r{sub +} and r{sub {minus}} which are the event and Cauchy horizons in the ''naked'' RN black hole, become spacelike in the perturbed geometry.

  19. Modified clock inequalities and modified black hole lifetime

    SciTech Connect (OSTI)

    Yang Rongjia; Zhang Shuangnan

    2009-06-15

    Based on a generalized uncertainty principle, Salecker-Wigner inequalities are modified. When applied to black holes, they give a modified black hole lifetime: T{sub MB}{approx}(M{sup 3}/m{sub p}{sup 3})(1-m{sub p}{sup 2}/M{sup 2})t{sub p}, and the number of bits required to specify the information content of the black hole as the event horizon area in Planck units N{approx}(M{sup 2}/m{sub p}{sup 2})(1-m{sub p}{sup 2}/M{sup 2})

  20. Are black holes in alternative theories serious astrophysical candidates? The case for Einstein-dilaton-Gauss-Bonnet black holes

    SciTech Connect (OSTI)

    Pani, Paolo; Cardoso, Vitor

    2009-04-15

    It is generally accepted that Einstein's theory will get some as yet unknown corrections, possibly large in the strong-field regime. An ideal place to look for these modifications is in the vicinities of compact objects such as black holes. Here, we study dilatonic black holes, which arise in the framework of Gauss-Bonnet couplings and one-loop corrected four-dimensional effective theory of heterotic superstrings at low energies. These are interesting objects as a prototype for alternative, yet well-behaved gravity theories: they evade the 'no-hair' theorem of general relativity but were proven to be stable against radial perturbations. We investigate the viability of these black holes as astrophysical objects and try to provide some means to distinguish them from black holes in general relativity. We start by extending previous works and establishing the stability of these black holes against axial perturbations. We then look for solutions of the field equations describing slowly rotating black holes and study geodesic motion around this geometry. Depending on the values of mass, dilaton charge, and angular momentum of the solution, one can have differences in the innermost-stable-circular-orbit location and orbital frequency, relative to black holes in general relativity. In the most favorable cases, the difference amounts to a few percent. Given the current state-of-the-art, we discuss the difficulty of distinguishing the correct theory of gravity from electromagnetic observations or even with gravitational-wave detectors.

  1. Proceedings of the black liquor research program review fourth meeting held July 28--30, 1987

    SciTech Connect (OSTI)

    Emerson, D. B.; Whitworth, B. A.

    1987-10-01

    Research programs, presented at the black liquor review meeting are described. Research topics include the following: Cooperative Program in Kraft Recovery; Black Liquor Physical Properties; Viscosity of Strong Black Liquor; Ultrafiltration of Kraft Black Liquor; Molecular Weight Distribution of Kraft Lignin; Black Liquor Droplet Formation Project; Fundamental Studies of Black Liquor Combustion; Black Liquor Combustion Sensors; Flash X-ray Imagining of Black Liquor Sprays; Laser Induced Fluorescence For Process Control In The Pulp and Paper Industry; Recovery Boiler Optimization; Black Liquor Gasification and Use of the Products in Combined-Cycle Cogeneration; Black Liquor Steam Plasma Automization; The B and W Pyrosonic 2000R System; Monsteras Boiler Control System; and Cooperative Program Project Reviews. Individual projects are processed separately for the data bases.

  2. Generic features of Einstein-Aether black holes

    SciTech Connect (OSTI)

    Tamaki, Takashi; Miyamoto, Umpei

    2008-01-15

    We reconsider spherically symmetric black hole solutions in Einstein-Aether theory with the condition that this theory has identical parametrized post-Newtonian parameters as those for general relativity, which is the main difference from the previous research. In contrast with previous study, we allow superluminal propagation of a spin-0 Aether-gravity wave mode. As a result, we obtain black holes having a spin-0 'horizon' inside an event horizon. We allow a singularity at a spin-0 horizon since it is concealed by the event horizon. If we allow such a configuration, the kinetic term of the Aether field can be large enough for black holes to be significantly different from Schwarzschild black holes with respect to Arnowitt-Deser-Misner mass, innermost stable circular orbit, Hawking temperature, and so on. We also discuss whether or not the above features can be seen in more generic vector-tensor theories.

  3. MLK Day/Black History Month DOE Celebration

    Broader source: Energy.gov [DOE]

    Join us as the Department honors both Dr. King and Black History Month with a dialogue on the history of civil rights for all. Secretary Ernest Moniz will open our program.

  4. The Role of Circulation Features on Black Carbon Transport into...

    Office of Scientific and Technical Information (OSTI)

    Carbon Transport into the Arctic in the Community Atmosphere Model Version 5 (CAM5) Citation Details In-Document Search Title: The Role of Circulation Features on Black Carbon ...

  5. Black hole evaporation in a noncommutative charged Vaidya model

    SciTech Connect (OSTI)

    Sharif, M. Javed, W.

    2012-06-15

    We study the black hole evaporation and Hawking radiation for a noncommutative charged Vaidya black hole. For this purpose, we determine a spherically symmetric charged Vaidya model and then formulate a noncommutative Reissner-Nordstroem-like solution of this model, which leads to an exact (t - r)-dependent metric. The behavior of the temporal component of this metric and the corresponding Hawking temperature are investigated. The results are shown in the form of graphs. Further, we examine the tunneling process of charged massive particles through the quantum horizon. We find that the tunneling amplitude is modified due to noncommutativity. Also, it turns out that the black hole evaporates completely in the limits of large time and horizon radius. The effect of charge is to reduce the temperature from a maximum value to zero. We note that the final stage of black hole evaporation is a naked singularity.

  6. Black Hills Energy (Gas) - Residential Energy Efficiency Program...

    Broader source: Energy.gov (indexed) [DOE]

    70% of cost Duct Repair and Sealing: 70% of cost Doors: 25 Summary Black Hills Energy (BHE) offers a variety of rebates for residential Colorado customers who purchase and...

  7. Paleoecology of the Devonian-Mississippian black-shale sequence...

    Office of Scientific and Technical Information (OSTI)

    The black shales contain abundant evidence of life from upper parts of the water column such as fish fossils, conodonts, algae and other phytoplankton; however, there is a lack of ...

  8. Atmospheric Radiation Measurement (ARM) Data from Black Forest...

    Office of Scientific and Technical Information (OSTI)

    ARM maintains four major, permanent sites for data collection and deploys the ARM Mobile Facility (AMF) to other sites as determined. In 2007 the AMF operated in the Black Forest ...

  9. Black Diamond, Washington: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    This article is a stub. You can help OpenEI by expanding it. Black Diamond is a city in King County, Washington. It falls under Washington's 8th congressional district.12...

  10. Black Branes in Flux Compactifications (Journal Article) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    Black Branes in Flux Compactifications Citation Details ... Report Number(s): SLAC-PUB-15462 arXiv:1306.3982 DOE Contract Number: AC02-76SF00515 Resource Type: Journal Article ...

  11. Multi-satellite simultaneous observations of magnetopause and atmospheric losses of radiation belt electrons during an intense solar wind dynamic pressure pulse

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Xiang, Zheng; Ni, Binbin; Zhou, Chen; Zou, Zhengyang; Gu, Xudong; Zhao, Zhengyu; Zhang, Xianguo; Zhang, Xiaoxin; Zhang, Shenyi; Li, Xinlin; et al

    2016-05-03

    Radiation belt electron flux dropouts are a kind of drastic variation in the Earth's magnetosphere, understanding of which is of both scientific and societal importance. We report multi-satellite simultaneous observations of magnetopause and atmospheric losses of radiation belt electrons during an event of intense solar wind dynamic pressure pulse, using electron flux data from a group of 14 satellites. Moreover, when the pulse occurred, magnetopause and atmospheric loss could take effect concurrently contributing to the electron flux dropout. Losses through the magnetopause were observed to be efficient and significant at L ≳ 5, owing to the magnetopause intrusion into Lmore » ~6 and outward radial diffusion associated with sharp negative gradient in electron phase space density. Losses to the atmosphere were directly identified from the precipitating electron flux observations, for which pitch angle scattering by plasma waves could be mainly responsible. While the convection and substorm injections strongly enhanced the energetic electron fluxes up to hundreds of keV, they could delay other than avoid the occurrence of electron flux dropout at these energies. Finally, we demonstrate that the pulse-time radiation belt electron flux dropout depends strongly on the specific interplanetary and magnetospheric conditions and that losses through the magnetopause and to the atmosphere and enhancements of substorm injection play an essential role in combination, which should be incorporated as a whole into future simulations for comprehending the nature of radiation belt electron flux dropouts.« less

  12. Celebrating Black History Month with DOE's Christopher Smith | Department

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    of Energy Black History Month with DOE's Christopher Smith Celebrating Black History Month with DOE's Christopher Smith February 16, 2011 - 12:08pm Addthis Christopher A. Smith Christopher A. Smith Assistant Secretary for Fossil Energy Throughout the month of February, we've been introducing remarkable African Americans who are working to advance the President's clean energy agenda. This week we're highlighting Christopher Smith, the Department's Deputy Assistant Secretary for Oil and

  13. Funds Awarded to Historically Black Colleges and Universities for Fossil

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Energy Research | Department of Energy Funds Awarded to Historically Black Colleges and Universities for Fossil Energy Research Funds Awarded to Historically Black Colleges and Universities for Fossil Energy Research October 7, 2014 - 10:26am Addthis Washington, D.C. - The U.S. Department of Energy (DOE) has selected four research projects that will provide educational and research training opportunities for minority students while advancing key technical areas in fossil fuel utilization.

  14. Black holes in supergravity: the non-BPS branch

    SciTech Connect (OSTI)

    Gimon, Eric; Gimon, Eric G.; Larsen, Finn; Simon, Joan

    2007-10-25

    We construct extremal, spherically symmetric black hole solutions to 4D supergravity with charge assignments that preclude BPS-saturation. In particular, we determine the ground state energy as a function of charges and moduli. We find that the mass of the non-BPS black hole remains that of a marginal bound state of four basic constituents throughout the entire moduli space and that there is always a non-zero gap above the BPS bound.

  15. Historically Black Colleges and Universities Receive Funds for Fossil

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Energy Research | Department of Energy Historically Black Colleges and Universities Receive Funds for Fossil Energy Research Historically Black Colleges and Universities Receive Funds for Fossil Energy Research August 15, 2013 - 1:18pm Addthis Washington, D.C. - Five fossil energy-related projects that will help maintain the nation's energy portfolio while also providing educational and research training opportunities for tomorrow's scientists and engineers have been selected for funding by

  16. Students, Faculty from Historically Black Colleges and Universities Share

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Research with EM Laboratory in Successful Exchange | Department of Energy Students, Faculty from Historically Black Colleges and Universities Share Research with EM Laboratory in Successful Exchange Students, Faculty from Historically Black Colleges and Universities Share Research with EM Laboratory in Successful Exchange February 5, 2013 - 12:00pm Addthis South Carolina State University students William Dumpson, left, and Alejandra Chirino, center, talk with Savannah River National

  17. Choice of an equivalent black body solar temperature

    SciTech Connect (OSTI)

    Parrott, J.E. )

    1993-09-01

    In the course of modeling the performance of photovoltaic solar cells for space use, it became desirable to set up a black body spectrum equivalent to the standard Air Mass Zero (AMO) solar spectrum. A method of calculating the equivalent black body solar surface temperature, based on irradiance and photon number flux derived from the AMO spectrum, is presented. It does not require knowledge of the angle subtended by the sun at the earth's surface. The value obtained is 5730 +/- 90 K.

  18. Drum drying of black liquor using superheated steam impinging jets

    SciTech Connect (OSTI)

    Shiravi, A.H.; Mujumdar, A.S.; Kubes, G.J. [McGill Univ., Montreal, Quebec (Canada)

    1997-05-01

    A novel drum dryer for black liquor utilizing multiple impinging jets of superheated steam was designed and built to evaluate the performance characteristics and effects of various operating parameters thereon. Appropriate ranges of parameters such as steam jet temperature and velocity were examined experimentally to quantify the optimal operating conditions for the formation of black liquor film on the drum surface as well as the drying kinetics.

  19. CHANGES OF THE SOLAR MERIDIONAL VELOCITY PROFILE DURING CYCLE 23 EXPLAINED BY FLOWS TOWARD THE ACTIVITY BELTS

    SciTech Connect (OSTI)

    Cameron, R. H.; Schuessler, M.

    2010-09-10

    The solar meridional flow is an important ingredient in Babcock-Leighton type models of the solar dynamo. Global variations of this flow have been suggested to explain the variations in the amplitudes and lengths of the activity cycles. Recently, cycle-related variations in the amplitude of the P{sup 1}{sub 2} term in the Legendre decomposition of the observed meridional flow have been reported. The result is often interpreted in terms of an overall variation in the flow amplitude during the activity cycle. Using a semi-empirical model based upon the observed distribution of magnetic flux on the solar surface, we show that the reported variations of the P{sup 1}{sub 2} term can be explained by the observed localized inflows into the active region belts. No variation of the overall meridional flow amplitude is required.

  20. Carbon black and carbon black-conducting polymer composites for environmental applications

    SciTech Connect (OSTI)

    Rajeshwar, K.; Wampler, W.A.; Goeringer, S.; Gerspacher, M.; Richardson, S.

    1996-10-01

    The preparation and use of the title materials for the treatment of Cr(VI) in aqueous media will be described. The carcinogenic Cr(VI) will be shown to be efficiently reduced to the less toxic specie Cr(III). The preparation and process variables will be described using a furnace black (N135) and polypyrrole as model candidates. Other aspects to be discussed include reaction kinetics, mechanism and thermodynamics. Finally, the practical implications of this new Cr(VI) pollution abatement approach are discussed.

  1. Controlled Sculpture of Black Phosphorus Nanoribbons

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Masih Das, Paul; Danda, Gopinath; Cupo, Andrew; Parkin, William M.; Liang, Liangbo; Kharche, Neerav; Ling, Xi; Huang, Shengxi; Dresselhaus, Mildred S.; Meunier, Vincent; et al

    2016-05-18

    Black phosphorus (BP) is a highly anisotropic allotrope of phosphorus with high promise for fast functional electronics and optoelectronics. We demonstrate that high-resolution and controlled structural modification of few-layer BP along arbitrary crystal direction can be achieved with nanometer-scale precision on a few-minute timescales leading to the formation of sub-nm wide armchair and zigzag BP nanoribbons. The nanoribbons are assembled, along with nanopores and nanogaps, using a combination of mechanical-liquid exfoliation and in situ transmission electron microscope (TEM) and scanning TEM nanosculpting. Here we report time-dependent structural properties of the one-dimensional systems under electron irradiation and probe their oxidation propertiesmore » with electron energy-loss spectroscopy (EELS). Finally, we demonstrate the use of STEM to controllably narrow and thin the nanoribbons until they break into nanogaps. The observations are rationalized using density functional theory for transition state calculations and electronic band-structure evolution for the various stages of the narrowing procedure. In particular, we predict that the sub- and few-nm wide BP nanoribbons realized experimentally possess clear one-dimensional quantum confinement, even when the systems are made up of a few layers. We find the demonstration of this procedure is key for the development of BP-based electronic, optoelectronic, thermoelectric, and other applications in reduced dimensions.« less

  2. Mechanical properties of reconstituted Australian black coal

    SciTech Connect (OSTI)

    Jasinge, D.; Ranjith, P.G.; Choi, S.K.; Kodikara, J.; Arthur, M.; Li, H.

    2009-07-15

    Coal is usually highly heterogeneous. Great variation in properties can exist among samples obtained even at close proximity within the same seam or within the same core sample. This makes it difficult to establish a correlation between uniaxial compressive strength (UCS) and point load index for coal. To overcome this problem, a method for making reconstituted samples for laboratory tests was developed. Samples were made by compacting particles of crushed coal mixed with cement and water. These samples were allowed to cure for four days. UCS and point load tests were performed to measure the geomechanical properties of the reconstituted coal. After four days curing, the average UCS was found to be approximately 4 MPa. This technical note outlines some experimental results and correlations that were developed to predict the mechanical properties of the reconstituted black coal samples. By reconstituting the samples from crushed coal, it is hoped that the samples will retain the important mechanical and physicochemical properties of coal, including the swelling, fluid transport, and gas sorption properties of coal. The aim is to be able to produce samples that are homogeneous with properties that are highly reproducible, and the reconstituted coal samples can be used for a number of research areas related to coal, including the long-term safe storage of CO{sub 2} in coal seams.

  3. Thermodynamics of Sultana-Dyer black hole

    SciTech Connect (OSTI)

    Majhi, Bibhas Ranjan

    2014-05-01

    The thermodynamical entities on the dynamical horizon are not naturally defined like the usual static cases. Here I find the temperature, Smarr formula and the first law of thermodynamics for the Sultana-Dyer metric which is related to the Schwarzschild spacetime by a time dependent conformal factor. To find the temperature (T), the chiral anomaly expressions for the two dimensional spacetime are used. This shows an application of the anomaly method to study Hawking effect for a dynamical situation. Moreover, the analysis singles out one expression for temperature among two existing expressions in the literature. Interestingly, the present form satisfies the first law of thermodynamics. Also, it relates the Misner-Sharp energy (Ē) and the horizon entropy ( S-bar ) by an algebraic expression Ē = 2 S-bar T which is the general form of the Smarr formula. This fact is similar to the usual static black hole cases in Einstein's gravity where the energy is identified as the Komar conserved quantity.

  4. Russian anthropogenic black carbon: Emission reconstruction and Arctic black carbon simulation

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Huang, Kan; Fu, Joshua S.; Prikhodko, Vitaly Y.; Storey, John M.; Romanov, Alexander; Hodson, Elke L.; Cresko, Joe; Morozova, Irina; Ignatieva, Yulia; Cabaniss, John

    2015-10-02

    Development of reliable source emission inventories is needed to advance the understanding of the origin of Arctic haze using chemical transport modeling. This paper develops a regional anthropogenic black carbon (BC) emission inventory for the Russian Federation, the largest country by land area in the Arctic Council. Activity data from combination of local Russia information and international resources, emission factors based on either Russian documents or adjusted values for local conditions, and other emission source data are used to approximate the BC emissions. Emissions are gridded at a resolution of 0.1° × 0.1° and developed into a monthly temporal profile.more » Total anthropogenic BC emission of Russia in 2010 is estimated to be around 224 Gg. Gas flaring, a commonly ignored black carbon source, contributes a significant fraction of 36.2% to Russia's total anthropogenic BC emissions. Other sectors, i.e., residential, transportation, industry, and power plants, contribute 25.0%, 20.3%, 13.1%, and 5.4%, respectively. Three major BC hot spot regions are identified: the European part of Russia, the southern central part of Russia where human population densities are relatively high, and the Urals Federal District where Russia's major oil and gas fields are located but with sparse human population. BC simulations are conducted using the hemispheric version of Community Multi-scale Air Quality Model with emission inputs from a global emission database EDGAR (Emissions Database for Global Atmospheric Research)-HTAPv2 (Hemispheric Transport of Air Pollution) and EDGAR-HTAPv2 with its Russian part replaced by the newly developed Russian BC emissions, respectively. The simulation using the new Russian BC emission inventory could improve 30–65% of absorption aerosol optical depth measured at the AERONET sites in Russia throughout the whole year as compared to that using the default HTAPv2 emissions. At the four ground monitoring sites (Zeppelin, Barrow, Alert

  5. Russian anthropogenic black carbon: Emission reconstruction and Arctic black carbon simulation

    SciTech Connect (OSTI)

    Huang, Kan; Fu, Joshua S.; Prikhodko, Vitaly Y.; Storey, John M.; Romanov, Alexander; Hodson, Elke L.; Cresko, Joe; Ignatieva, Yulia; Cabaniss, John

    2015-10-02

    Development of reliable source emission inventories is needed to advance the understanding of the origin of Arctic haze using chemical transport modeling. This paper develops a regional anthropogenic black carbon (BC) emission inventory for the Russian Federation, the largest country by land area in the Arctic Council. Activity data from combination of local Russia information and international resources, emission factors based on either Russian documents or adjusted values for local conditions, and other emission source data are used to approximate the BC emissions. Emissions are gridded at a resolution of 0.1° × 0.1° and developed into a monthly temporal profile. Total anthropogenic BC emission of Russia in 2010 is estimated to be around 224 Gg. Gas flaring, a commonly ignored black carbon source, contributes a significant fraction of 36.2% to Russia's total anthropogenic BC emissions. Other sectors, i.e., residential, transportation, industry, and power plants, contribute 25.0%, 20.3%, 13.1%, and 5.4%, respectively. Three major BC hot spot regions are identified: the European part of Russia, the southern central part of Russia where human population densities are relatively high, and the Urals Federal District where Russia's major oil and gas fields are located but with sparse human population. BC simulations are conducted using the hemispheric version of Community Multi-scale Air Quality Model with emission inputs from a global emission database EDGAR (Emissions Database for Global Atmospheric Research)-HTAPv2 (Hemispheric Transport of Air Pollution) and EDGAR-HTAPv2 with its Russian part replaced by the newly developed Russian BC emissions, respectively. The simulation using the new Russian BC emission inventory could improve 30–65% of absorption aerosol optical depth measured at the AERONET sites in Russia throughout the whole year as compared to that using the default HTAPv2 emissions. At the four ground monitoring sites (Zeppelin, Barrow, Alert, and

  6. Stellar black holes and the origin of cosmic acceleration

    SciTech Connect (OSTI)

    Prescod-Weinstein, Chanda; Afshordi, Niayesh; Balogh, Michael L.

    2009-08-15

    The discovery of cosmic acceleration has presented a unique challenge for cosmologists. As observational cosmology forges ahead, theorists have struggled to make sense of a standard model that requires extreme fine-tuning. This challenge is known as the cosmological constant problem. The theory of gravitational aether is an alternative to general relativity that does not suffer from this fine-tuning problem, as it decouples the quantum field theory vacuum from geometry, while remaining consistent with other tests of gravity. In this paper, we study static black hole solutions in this theory and show that it manifests a UV-IR coupling: Aether couples the space-time metric close to the black hole horizon, to metric at infinity. We then show that using the trans-Planckian ansatz (as a quantum gravity effect) close to the black hole horizon, leads to an accelerating cosmological solution, far from the horizon. Interestingly, this acceleration matches current observations for stellar-mass black holes. Based on our current understanding of the black hole accretion history in the Universe, we then make a prediction for how the effective dark energy density should evolve with redshift, which can be tested with future dark energy probes.

  7. Transport properties of ultrathin black phosphorus on hexagonal boron nitride

    SciTech Connect (OSTI)

    Doganov, Rostislav A.; zyilmaz, Barbaros; Koenig, Steven P.; Yeo, Yuting; Watanabe, Kenji; Taniguchi, Takashi

    2015-02-23

    Ultrathin black phosphorus, or phosphorene, is a two-dimensional material that allows both high carrier mobility and large on/off ratios. Similar to other atomic crystals, like graphene or layered transition metal dichalcogenides, the transport behavior of few-layer black phosphorus is expected to be affected by the underlying substrate. The properties of black phosphorus have so far been studied on the widely utilized SiO{sub 2} substrate. Here, we characterize few-layer black phosphorus field effect transistors on hexagonal boron nitridean atomically smooth and charge trap-free substrate. We measure the temperature dependence of the field effect mobility for both holes and electrons and explain the observed behavior in terms of charged impurity limited transport. We find that in-situ vacuum annealing at 400?K removes the p-doping of few-layer black phosphorus on both boron nitride and SiO{sub 2} substrates and reduces the hysteresis at room temperature.

  8. Can reducing black carbon emissions counteract global warming?

    SciTech Connect (OSTI)

    Tami C. Bond; Haolin Sun

    2005-08-15

    Field measurements and model results have recently shown that aerosols may have important climatic impacts. One line of inquiry has investigated whether reducing climate-warming soot or black carbon aerosol emissions can form a viable component of mitigating global warming. Black carbon is produced by poor combustion, from our example hard coal cooking fires for and industrial pulverized coal boilers. The authors review and acknowledge scientific arguments against considering aerosols and greenhouse gases in a common framework, including the differences in the physical mechanisms of climate change and relevant time scales. It is argued that such a joint consideration is consistent with the language of the United Nations Framework Convention on Climate Change. Results from published climate-modeling studies are synthesized to obtain a global warming potential for black carbon relative to that of CO{sub 2} (680 on a 100 year basis). This calculation enables a discussion of cost-effectiveness for mitigating the largest sources of black carbon. It is found that many emission reductions are either expensive or difficult to enact when compared with greenhouse gases, particularly in Annex I countries. Finally, a role for black carbon in climate mitigation strategies is proposed that is consistent with the apparently conflicting arguments raised during the discussion. Addressing these emissions is a promising way to reduce climatic interference primarily for nations that have not yet agreed to address greenhouse gas emissions and provides the potential for a parallel climate agreement. 31 refs., 3 figs., 1 tab.

  9. Topological black holes in Lovelock-Born-Infeld gravity

    SciTech Connect (OSTI)

    Dehghani, M. H.; Alinejadi, N.; Hendi, S. H.

    2008-05-15

    In this paper, we present topological black holes of third order Lovelock gravity in the presence of cosmological constant and nonlinear electromagnetic Born-Infeld field. Depending on the metric parameters, these solutions may be interpreted as black hole solutions with inner and outer event horizons, an extreme black hole or naked singularity. We investigate the thermodynamics of asymptotically flat solutions and show that the thermodynamic and conserved quantities of these black holes satisfy the first law of thermodynamic. We also endow the Ricci flat solutions with a global rotation and calculate the finite action and conserved quantities of these class of solutions by using the counterterm method. We compute the entropy through the use of the Gibbs-Duhem relation and find that the entropy obeys the area law. We obtain a Smarr-type formula for the mass as a function of the entropy, the angular momenta, and the charge, and compute temperature, angular velocities, and electric potential and show that these thermodynamic quantities coincide with their values which are computed through the use of geometry. Finally, we perform a stability analysis for this class of solutions in both the canonical and the grand-canonical ensemble and show that the presence of a nonlinear electromagnetic field and higher curvature terms has no effect on the stability of the black branes, and they are stable in the whole phase space.

  10. Hard, infrared black coating with very low outgassing

    SciTech Connect (OSTI)

    Kuzmenko, P J; Behne, D M; Casserly, T; Boardman, W; Upadhyaya, D; Boinapally, K; Gupta, M; Cao, Y

    2008-06-02

    Infrared astronomical instruments require absorptive coatings on internal surfaces to trap scattered and stray photons. This is typically accomplished with any one of a number of black paints. Although inexpensive and simple to apply, paint has several disadvantages. Painted surfaces can be fragile, prone to shedding particles, and difficult to clean. Most importantly, the vacuum performance is poor. Recently a plasma enhanced chemical vapor deposition (PECVD) process was developed to apply thick (30 {micro}m) diamond-like carbon (DLC) based protective coatings to the interior of oil pipelines. These DLC coatings show much promise as an infrared black for an ultra high vacuum environment. The coatings are very robust with excellent cryogenic adhesion. Their total infrared reflectivity of < 10% at normal incidence approaches that of black paints. We measured outgas rates of <10{sup -12} Torr liter/sec cm{sup 2}, comparable to bare stainless steel.

  11. Planck-Size Black Hole Remnants as Dark Matter

    SciTech Connect (OSTI)

    Chen, P

    2004-09-13

    While there exist various candidates, the nature of dark matter remains unresolved. Recently it was argued that the generalized uncertainty principle (GUP) may prevent a black hole from evaporating completely, and as a result there should exist a Planck-size black hole remnant (BHR) at the end of its evaporation. If a sufficient amount of small black holes can be produced in the early universe, then the resultant BHRs can be an interesting candidate for DM. We demonstrate that this is indeed the case for the hybrid inflation model. By assuming BHR as DM, our notion imposes a constraint on the hybrid inflation potential. We show that such a constraint is not so fine-tuned. Possible observational signatures are briefly discussed.

  12. Safeguards Approaches for Black Box Processes or Facilities

    SciTech Connect (OSTI)

    Diaz-Marcano, Helly; Gitau, Ernest TN; Hockert, John; Miller, Erin; Wylie, Joann

    2013-09-25

    The objective of this study is to determine whether a safeguards approach can be developed for “black box” processes or facilities. These are facilities where a State or operator may limit IAEA access to specific processes or portions of a facility; in other cases, the IAEA may be prohibited access to the entire facility. The determination of whether a black box process or facility is safeguardable is dependent upon the details of the process type, design, and layout; the specific limitations on inspector access; and the restrictions placed upon the design information that can be provided to the IAEA. This analysis identified the necessary conditions for safeguardability of black box processes and facilities.

  13. Black holes in a box: Toward the numerical evolution of black holes in AdS space-times

    SciTech Connect (OSTI)

    Witek, Helvi; Nerozzi, Andrea; Cardoso, Vitor; Herdeiro, Carlos; Sperhake, Ulrich; Zilhao, Miguel

    2010-11-15

    The evolution of black holes in ''confining boxes'' is interesting for a number of reasons, particularly because it mimics the global structure of anti-de Sitter geometries. These are nonglobally hyperbolic space-times and the Cauchy problem may only be well defined if the initial data are supplemented by boundary conditions at the timelike conformal boundary. Here, we explore the active role that boundary conditions play in the evolution of a bulk black hole system, by imprisoning a black hole binary in a box with mirrorlike boundary conditions. We are able to follow the post-merger dynamics for up to two reflections off the boundary of the gravitational radiation produced in the merger. We estimate that about 15% of the radiation energy is absorbed by the black hole per interaction, whereas transfer of angular momentum from the radiation to the black hole is observed only in the first interaction. We discuss the possible role of superradiant scattering for this result. Unlike the studies with outgoing boundary conditions, both of the Newman-Penrose scalars {Psi}{sub 4} and {Psi}{sub 0} are nontrivial in our setup, and we show that the numerical data verifies the expected relations between them.

  14. Greybody factors for Myers–Perry black holes

    SciTech Connect (OSTI)

    Boonserm, Petarpa; Chatrabhuti, Auttakit Ngampitipan, Tritos; Visser, Matt

    2014-11-15

    The Myers–Perry black holes are higher-dimensional generalizations of the usual (3+1)-dimensional rotating Kerr black hole. They are of considerable interest in Kaluza–Klein models, specifically within the context of brane-world versions thereof. In the present article, we shall consider the greybody factors associated with scalar field excitations of the Myers–Perry spacetimes, and develop some rigorous bounds on these greybody factors. These bounds are of relevance for characterizing both the higher-dimensional Hawking radiation, and the super-radiance, that is expected for these spacetimes.

  15. Black liquor gasification phase 2D final report

    SciTech Connect (OSTI)

    Kohl, A.L.; Stewart, A.E.

    1988-06-01

    This report covers work conducted by Rockwell International under Amendment 5 to Subcontract STR/DOE-12 of Cooperative Agreement DE-AC-05-80CS40341 between St. Regis Corporation (now Champion International) and the Department of Energy (DOE). The work has been designated Phase 2D of the overall program to differentiate it from prior work under the same subcontract. The overall program is aimed at demonstrating the feasibility of and providing design data for the Rockwell process for gasifying Kraft black liquor. In this process, concentrated black liquor is converted into low-Btu fuel gas and reduced melt by reaction with air in a specially designed gasification reactor.

  16. We the Geeks: Celebrating Black History Month | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    the Geeks: Celebrating Black History Month We the Geeks: Celebrating Black History Month February 24, 2014 - 9:40am Addthis President Barack Obama talks with Evan Jackson, 10, Alec Jackson, 8, and Caleb Robinson, 8, from McDonough, Ga., while looking at exhibits at the White House Science Fair in the State Dining Room, April 22, 2013. The sports-loving grade-schoolers created a new product concept to keep athletes cool and helps players maintain safe body temperatures on the field. | Official

  17. Black and gray Helmholtz-Kerr soliton refraction

    SciTech Connect (OSTI)

    Sanchez-Curto, Julio; Chamorro-Posada, Pedro; McDonald, Graham S.

    2011-01-15

    Refraction of black and gray solitons at boundaries separating different defocusing Kerr media is analyzed within a Helmholtz framework. A universal nonlinear Snell's law is derived that describes gray soliton refraction, in addition to capturing the behavior of bright and black Kerr solitons at interfaces. Key regimes, defined by beam and interface characteristics, are identified, and predictions are verified by full numerical simulations. The existence of a unique total nonrefraction angle for gray solitons is reported; both internal and external refraction at a single interface is shown possible (dependent only on incidence angle). This, in turn, leads to the proposal of positive or negative lensing operations on soliton arrays at planar boundaries.

  18. SP2 Deployment at Boston College-Aerodyne-Led Coated Black Carbon...

    Office of Scientific and Technical Information (OSTI)

    Coated Black Carbon Study (BC4) Final Campaign Summary Citation Details In-Document Search Title: SP2 Deployment at Boston College-Aerodyne-Led Coated Black Carbon Study (BC4) ...

  19. Stability of Hořava-Lifshitz black holes in the context of AdS...

    Office of Scientific and Technical Information (OSTI)

    Stability of Hoava-Lifshitz black holes in the context of AdSCFT Citation Details In-Document Search Title: Stability of Hoava-Lifshitz black holes in the context of AdSCFT ...

  20. V-069: BlackBerry Tablet OS Adobe Flash Player and Samba Multiple...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    9: BlackBerry Tablet OS Adobe Flash Player and Samba Multiple Vulnerabilities V-069: BlackBerry Tablet OS Adobe Flash Player and Samba Multiple Vulnerabilities January 15, 2013 -...

  1. Geometry and evolution of the frontal part of the Magallanes foreland thrust and fold belt (Vicuna Area), Tierra del Fuego, southern Chile

    SciTech Connect (OSTI)

    Alvarez-Marron, J.; McClay, K.R. ); Harambour, S.; Rojas, L.; Skarmeta, J. )

    1993-11-01

    The Magallanes foreland thrust and fold belt is a thin-skinned foreland thrust and fold belt of Paleocene to Oligocene age that deforms Upper Jurassic through Tertiary volcanic, volcaniclastic, and siliciclastic strata of the Magallanes basin, southern Andean Cordillera, Chile. This paper is a detailed description and analysis of the geology and structural evolution of the thrust front (Vicuna area of southern Tierra del Fuego). Reflection seismic and well data, together with 1:50,000 scale geological mapping, have been used in the analysis. In the southern part of the Vicuna area, two different thrust systems have been found: an upper imbricate fan that deforms Upper Jurassic and Cretaceous strata, and a younger, lower duplex composed of Cretaceous and probably Upper Jurassic rocks. The imbricate fan is characterized by fault-propagation folding in which listric thrust faults merge downward into a sole thrust that probably is located within the Upper Jurassic stratigraphy. The sole thrust of the upper imbricates forms the roof thrust of the underlying duplex. In the northern part of the Vicuna area, the syntectonic sedimentary wedge of the foredeep consists of Late Cretaceous through Tertiary siliciclastics that have been deformed and uplifted by passive back thrusting at the triangle zone. The structural style in the foreland region shows three main subhorizontal detachment levels located within the sedimentary wedge as a result of the progressive transfer of slip from the thrust belt to the foreland. Minor blind thrusts produce stacked [open quotes]pop up[close quotes] and triangle structures that result in complex geometries in the cores of anticlines. A forward-breaking sequence of thrusting is interpreted. During deformation, the active foredeep wedge migrated at least 10 km northward. Balanced geological cross sections indicate approximately 60% (-30 km) shortening for this part of the Magallanes thrust belt.

  2. THE SPITZER SURVEY OF INTERSTELLAR CLOUDS IN THE GOULD BELT. II. THE CEPHEUS FLARE OBSERVED WITH IRAC AND MIPS

    SciTech Connect (OSTI)

    Kirk, Jason M.; Ward-Thompson, Derek; Di Francesco, James E-mail: derek.ward-thompson@astro.cf.ac.uk

    2009-11-01

    We present Spitzer Infrared Array Camera (IRAC; {approx}2 deg{sup 2}) and Multiband Imaging Photometer for Spitzer (MIPS; {approx}8 deg{sup 2}) observations of the Cepheus Flare, which is associated with the Gould Belt, at an approximate distance of {approx}300 pc. Around 6500 sources are detected in all four IRAC bands, of which {approx}900 have MIPS 24 {mu}m detections. We identify 133 young stellar object (YSO) candidates using color-magnitude diagram techniques, and a large number of the YSO candidates are associated with the NGC 7023 reflection nebula. Cross-identifications were made with the Guide Star Catalog II and the IRAS Faint Source Catalog, and spectral energy distributions (SEDs) were constructed. SED modeling was conducted to estimate the degree of infrared excess. It was found that a large majority of disks were optically thick accreting disks, suggesting that there has been little disk evolution in these sources. Nearest-neighbor clustering analysis identified four small protostellar groups (L1228, L1228N, L1251A, and L1251B) with 5-15 members each and the larger NGC 7023 association with 32 YSO members. The star-formation efficiency for cores with clusters of protostars and for those without clusters was found to be {approx}8% and {approx}1%, respectively. The cores L1155, L1241, and L1247 are confirmed to be starless down to our luminosity limit of L {sub bol} = 0.06 L {sub sun}.

  3. A Summary of Information on the Behavior of the Yakima Fold Belt as a Structural Entity -- Topical Report

    SciTech Connect (OSTI)

    Last, George V.; Winsor, Kelsey; Unwin, Stephen D.

    2012-08-01

    This document is one in a series of topical reports compiled by the Pacific Northwest National Laboratory to summarize technical information on selected topics important to the performance of a probabilistic seismic hazard analysis (PSHA) of the Hanford Site. The purpose of this report is to summarize available data and analyses relevant to the Yakima Fold Belt (YFB) that may bear on the question of whether or not the YFB behaves as a single seismotectonic province in which activity along one fold structure is representative of behavior along all other fold structures. This topic has met with a fairly high level of contention in the expert community and has the potential to result in significant impacts on an evaluation of seismic hazard at the Hanford Site. This report defines the relevant alternative conceptual models relevant to this technical issue and the arguments and data that support those models. It provides a brief description of the technical issue and principal uncertainties; a general overview on the nature of the technical issue, along with alternative conceptual models, supporting arguments and information, and uncertainties; and finally, it suggests some possible approaches for reducing uncertainties regarding this issue.

  4. A Summary of Coupled, Uncoupled, and Hybrid Tectonic Models for the Yakima Fold Belt--Topical Report

    SciTech Connect (OSTI)

    Chamness, Michele A.; Winsor, Kelsey; Unwin, Stephen D.

    2012-08-01

    This document is one in a series of topical reports compiled by the Pacific Northwest National Laboratory to summarize technical information on selected topics important to the performance of a probabilistic seismic hazard analysis of the Hanford Site. The purpose of this report is to summarize the range of opinions and supporting information expressed by the expert community regarding whether a coupled or uncoupled model, or a combination of both, best represents structures in the Yakima Fold Belt. This issue was assessed to have a high level of contention with up to moderate potential for impact on the hazard estimate. This report defines the alternative conceptual models relevant to this technical issue and the arguments and data that support those models. It provides a brief description of the technical issue and principal uncertainties; a general overview on the nature of the technical issue, along with alternative conceptual models, supporting arguments and information, and uncertainties; and finally, suggests some possible approaches for reducing uncertainties regarding this issue.

  5. CONSTRAINTS ON THE PHYSICAL PROPERTIES OF MAIN BELT COMET P/2013 R3 FROM ITS BREAKUP EVENT

    SciTech Connect (OSTI)

    Hirabayashi, Masatoshi; Snchez, Diego Paul; Gabriel, Travis; Scheeres, Daniel J.

    2014-07-01

    Jewitt etal. recently reported that main belt comet P/2013 R3 experienced a breakup, probably due to rotational disruption, with its components separating on mutually hyperbolic orbits. We propose a technique for constraining physical properties of the proto-body, especially the initial spin period and cohesive strength, as a function of the body's estimated size and density. The breakup conditions are developed by combining mutual orbit dynamics of the smaller components and the failure condition of the proto-body. Given a proto-body with a bulk density ranging from 1000kgm{sup 3} to 1500kgm{sup 3} (a typical range of the bulk density of C-type asteroids), we obtain possible values of the cohesive strength (40-210Pa) and the initial spin state (0.48-1.9hr). From this result, we conclude that although the proto-body could have been a rubble pile, it was likely spinning beyond its gravitational binding limit and would have needed cohesive strength to hold itself together. Additional observations of P/2013 R3 will enable stronger constraints on this event, and the present technique will be able to give more precise estimates of its internal structure.

  6. BLACK HOLE MASS ESTIMATES AND RAPID GROWTH OF SUPERMASSIVE BLACK HOLES IN LUMINOUS z ∼ 3.5 QUASARS

    SciTech Connect (OSTI)

    Zuo, Wenwen; Wu, Xue-Bing; Fan, Xiaohui; Green, Richard; Wang, Ran; Bian, Fuyan

    2015-02-01

    We present new near-infrared (IR) observations of the Hβ λ4861 and Mg II λ2798 lines for 32 luminous quasars with 3.2 < z < 3.9 using the Palomar Hale 200 inch telescope and the Large Binocular Telescope. We find that the Mg II FWHM is well correlated with the Hβ FWHM, confirming itself as a good substitute for the Hβ FWHM in the black hole mass estimates. The continuum luminosity at 5100 Å well correlates with the continuum luminosity at 3000 Å and the broad emission line luminosities (Hβ and Mg II). With simultaneous near-IR spectroscopy of the Hβ and Mg II lines to exclude the influences of flux variability, we are able to evaluate the reliability of estimating black hole masses based on the Mg II line for high redshift quasars. With the reliable Hβ line based black hole mass and Eddington ratio estimates, we find that the z ∼ 3.5 quasars in our sample have black hole masses 1.90 × 10{sup 9} M {sub ☉} ≲ M {sub BH} ≲ 1.37 × 10{sup 10} M {sub ☉}, with a median of ∼5.14 × 10{sup 9} M {sub ☉} and are accreting at Eddington ratios between 0.30 and 3.05, with a median of ∼1.12. Assuming a duty cycle of 1 and a seed black hole mass of 10{sup 4} M {sub ☉}, we show that the z ∼ 3.5 quasars in this sample can grow to their estimated black hole masses within the age of the universe at their redshifts.

  7. WBA-15-0009 - In the Matter of Sandra Black | Department of Energy

    Energy Savers [EERE]

    9 - In the Matter of Sandra Black WBA-15-0009 - In the Matter of Sandra Black On December 31, 2015, OHA denied an Appeal involving a Complaint filed by Sandra Black against Savannah River Nuclear Solutions, LLC (SRNS) under the DOE's Contractor Employee Protection Program, 10 CFR Part 708. In her Complaint, Black alleged SRNS terminated her for engaging in protected activities, specifically citing her participation in a Government Accountability Office review as a protected disclosure. An OHA

  8. NREL's Black Silicon Increases Solar Cell Efficiency by Reducing Reflected Sunlight (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2010-11-01

    A fact sheet detailing the R&D 100 Award-winning Black Silicon Nanocatalytic Wet-Chemical Etch technology.

  9. Cold warriors target arms control (Journal Article) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    to achieve a comprehensive test ban (CTB) by 1996. US leadership in the post-Cold War era will undermined as the international community, already skeptical about this ...

  10. Dissipative effects in the worldline approach to black hole dynamics

    SciTech Connect (OSTI)

    Goldberger, Walter D.; Rothstein, Ira Z.

    2006-05-15

    We derive a long wavelength effective point-particle description of four-dimensional Schwarzschild black holes. In this effective theory, absorptive effects are incorporated by introducing degrees of freedom localized on the worldline that mimic the interaction between the horizon and bulk fields. The correlation functions of composite operators in this worldline theory can be obtained by standard matching calculations. For example, we obtain the low frequency two-point function of multipole worldline operators by relating them to the long wavelength graviton black hole absorptive cross section. The effective theory is then used to predict the leading effects of absorption in several astrophysically motivated examples, including the dynamics of nonrelativistic black hole binary inspirals and the motion of a small black hole in an arbitrary background geometry. Our results can be written compactly in terms of absorption cross sections, and can be easily applied to the dissipative dynamics of any compact object, e.g. neutron stars. The relation of our methodology to that developed in the context of the AdS/CFT correspondence is discussed.

  11. Entanglement entropy of two black holes and entanglement entropic force

    SciTech Connect (OSTI)

    Shiba, Noburo

    2011-03-15

    We study the entanglement entropy S{sub C} of the massless free scalar field on the outside region C of two black holes A and B whose radii are R{sub 1} and R{sub 2} and how it depends on the distance r(>>R{sub 1},R{sub 2}) between two black holes. If we can consider the entanglement entropy as thermodynamic entropy, we can see the entropic force acting on the two black holes from the r dependence of S{sub C}. We develop the computational method based on that of Bombelli et al. to obtain the r dependence of S{sub C} of scalar fields whose Lagrangian is quadratic with respect to the scalar fields. First, we study S{sub C} in (d+1)-dimensional Minkowski spacetime. In this case the state of the massless free scalar field is the Minkowski vacuum state, and we replace two black holes by two imaginary spheres and take the trace over the degrees of freedom residing in the imaginary spheres. We obtain the leading term of S{sub C} with respect to 1/r. The result is S{sub C}=S{sub A}+S{sub B}+(1/r{sup 2d-2})G(R{sub 1},R{sub 2}), where S{sub A} and S{sub B} are the entanglement entropy on the inside region of A and B, respectively, and G(R{sub 1},R{sub 2}){<=}0. We do not calculate G(R{sub 1},R{sub 2}) in detail, but we show how to calculate it. In the black hole case we use the method used in the Minkowski spacetime case with some modifications. We show that S{sub C} can be expected to be the same form as that in the Minkowski spacetime case. But in the black hole case, S{sub A} and S{sub B} depend on r, so we do not fully obtain the r dependence of S{sub C}. Finally, we assume that the entanglement entropy can be regarded as thermodynamic entropy and consider the entropic force acting on two black holes. We argue how to separate the entanglement entropic force from other forces and how to cancel S{sub A} and S{sub B} whose r dependences are not obtained. Then we obtain the physical prediction, which can be tested experimentally in principle.

  12. THE SPITZER SURVEY OF INTERSTELLAR CLOUDS IN THE GOULD BELT. V. OPHIUCHUS NORTH OBSERVED WITH IRAC AND MIPS

    SciTech Connect (OSTI)

    Hatchell, J.; Terebey, S.; Huard, T.; Mamajek, E. E. E-mail: sterebe@calstatela.edu; and others

    2012-08-01

    We present Spitzer IRAC (2.1 deg{sup 2}) and MIPS (6.5 deg{sup 2}) observations of star formation in the Ophiuchus North (Oph N) molecular clouds. This fragmentary cloud complex lies on the edge of the Sco-Cen OB association, several degrees to the north of the well-known {rho} Oph star-forming region, at an approximate distance of 130 pc. The Oph N clouds were mapped as part of the Spitzer Gould Belt project under the working name 'Scorpius'. In the regions mapped, selected to encompass all the cloud with visual extinction A{sub V} > 3, 11 young stellar object (YSO) candidates are identified, 8 from IRAC/MIPS color-based selection and 3 from Two Micron All Sky Survey (2MASS) K{sub S} /MIPS colors. Adding to one source previously identified in L43, this increases the number of YSOcs identified in Oph N to 12. During the selection process, four color-based YSOcs were rejected as probable asymptotic giant branch stars and one as a known galaxy. The sources span the full range of YSOc classifications from Class 0/1 to Class III, and starless cores are also present. Twelve high extinction (A{sub V} > 10) cores are identified with a total mass of {approx}100 M{sub Sun }. These results confirm that there is little ongoing star formation in this region (instantaneous star formation efficiency <0.34%) and that the bottleneck lies in the formation of dense cores. The influence of the nearby Upper Sco OB association, including the 09V star {zeta} Oph, is seen in dynamical interactions and raised dust temperatures but has not enhanced levels of star formation in Oph N.

  13. THE SPITZER SURVEY OF INTERSTELLAR CLOUDS IN THE GOULD BELT. IV. LUPUS V AND VI OBSERVED WITH IRAC AND MIPS

    SciTech Connect (OSTI)

    Spezzi, Loredana; Vernazza, Pierre; Merin, Bruno; Allen, Lori E.; Evans, Neal J. II; Harvey, Paul M.; Joergensen, Jes K.; Bourke, Tyler L.; Peterson, Dawn; Cieza, Lucas A.; Dunham, Michael M.; Huard, Tracy L.; Tothill, Nick F. H.

    2011-04-01

    We present Gould's Belt (GB) Spitzer IRAC and MIPS observations of the Lupus V and VI clouds and discuss them in combination with near-infrared (2MASS) data. Our observations complement those obtained for other Lupus clouds within the frame of the Spitzer 'Core to Disk' (c2d) Legacy Survey. We found 43 young stellar object (YSO) candidates in Lupus V and 45 in Lupus VI, including two transition disks, using the standard c2d/GB selection method. None of these sources was classified as a pre-main-sequence star from previous optical, near-IR, and X-ray surveys. A large majority of these YSO candidates appear to be surrounded by thin disks (Class III; {approx}79% in Lupus V and {approx}87% in Lupus VI). These Class III abundances differ significantly from those observed for the other Lupus clouds and c2d/GB surveyed star-forming regions, where objects with optically thick disks (Class II) dominate the young population. We investigate various scenarios that can explain this discrepancy. In particular, we show that disk photoevaporation due to nearby OB stars is not responsible for the high fraction of Class III objects. The gas surface densities measured for Lupus V and VI lie below the star formation threshold (A{sub V} {approx} 8.6 mag), while this is not the case for other Lupus clouds. Thus, few Myr older age for the YSOs in Lupus V and VI with respect to other Lupus clouds is the most likely explanation of the high fraction of Class III objects in these clouds, while a higher characteristic stellar mass might be a contributing factor. Better constraints on the age and binary fraction of the Lupus clouds might solve the puzzle but require further observations.

  14. The influences of solar wind pressure and interplanetary magnetic field on global magnetic field and outer radiation belt electrons

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Yu, J.; Li, L. Y.; Cao, J. B.; Reeves, Geoffrey D.; Baker, D. N.; Spence, H.

    2016-07-22

    Using the Van Allen Probe in situ measured magnetic field and electron data, we examine the solar wind dynamic pressure and interplanetary magnetic field (IMF) effects on global magnetic field and outer radiation belt relativistic electrons (≥1.8 MeV). The dynamic pressure enhancements (>2 nPa) cause the dayside magnetic field increase and the nightside magnetic field reduction, whereas the large southward IMFs (Bz-IMF < –2nT) mainly lead to the decrease of the nightside magnetic field. In the dayside increased magnetic field region (magnetic local time (MLT) ~ 06:00–18:00, and L > 4), the pitch angles of relativistic electrons are mainly pancakemore » distributions with a flux peak around 90° (corresponding anisotropic index A > 0.1), and the higher-energy electrons have stronger pancake distributions (the larger A), suggesting that the compression-induced betatron accelerations enhance the dayside pancake distributions. However, in the nighttime decreased magnetic field region (MLT ~ 18:00–06:00, and L ≥ 5), the pitch angles of relativistic electrons become butterfly distributions with two flux peaks around 45° and 135° (A < 0). The spatial range of the nighttime butterfly distributions is almost independent of the relativistic electron energy, but it depends on the magnetic field day-night asymmetry and the interplanetary conditions. The dynamic pressure enhancements can make the nighttime butterfly distribution extend inward. The large southward IMFs can also lead to the azimuthal expansion of the nighttime butterfly distributions. As a result, these variations are consistent with the drift shell splitting and/or magnetopause shadowing effect.« less

  15. Advancement of High Temperature Black Liquor Gasification Technology

    SciTech Connect (OSTI)

    Craig Brown; Ingvar Landalv; Ragnar Stare; Jerry Yuan; Nikolai DeMartini; Nasser Ashgriz

    2008-03-31

    Weyerhaeuser operates the world's only commercial high-temperature black liquor gasifier at its pulp mill in New Bern, NC. The unit was started-up in December 1996 and currently processes about 15% of the mill's black liquor. Weyerhaeuser, Chemrec AB (the gasifier technology developer), and the U.S. Department of Energy recognized that the long-term, continuous operation of the New Bern gasifier offered a unique opportunity to advance the state of high temperature black liquor gasification toward the commercial-scale pressurized O2-blown gasification technology needed as a foundation for the Forest Products Bio-Refinery of the future. Weyerhaeuser along with its subcontracting partners submitted a proposal in response to the 2004 joint USDOE and USDA solicitation - 'Biomass Research and Development Initiative'. The Weyerhaeuser project 'Advancement of High Temperature Black Liquor Gasification' was awarded USDOE Cooperative Agreement DE-FC26-04NT42259 in November 2004. The overall goal of the DOE sponsored project was to utilize the Chemrec{trademark} black liquor gasification facility at New Bern as a test bed for advancing the development status of molten phase black liquor gasification. In particular, project tasks were directed at improvements to process performance and reliability. The effort featured the development and validation of advanced CFD modeling tools and the application of these tools to direct burner technology modifications. The project also focused on gaining a fundamental understanding and developing practical solutions to address condensate and green liquor scaling issues, and process integration issues related to gasifier dregs and product gas scrubbing. The Project was conducted in two phases with a review point between the phases. Weyerhaeuser pulled together a team of collaborators to undertake these tasks. Chemrec AB, the technology supplier, was intimately involved in most tasks, and focused primarily on the design, specification and

  16. All or nothing: On the small fluctuations of two-dimensional string theoretic black holes

    SciTech Connect (OSTI)

    Gilbert, Gerald; Raiten, Eric

    1992-10-01

    A comprehensive analysis of small fluctuations about two-dimensional string-theoretic and string-inspired black holes is presented. It is shown with specific examples that two-dimensional black holes behave in a radically different way from all known black holes in four dimensions. For both the SL(2,R)/U(1) black hole and the two-dimensional black hole coupled to a massive dilaton with constant field strength, it is shown that there are a {\\it continuous infinity} of solutions to the linearized equations of motion, which are such that it is impossible to ascertain the classical linear response. It is further shown that the two-dimensional black hole coupled to a massive, linear dilaton admits {\\it no small fluctuations at all}. We discuss possible implications of our results for the Callan-Giddings-Harvey-Strominger black hole.

  17. T-668: Vulnerability in a BlackBerry Enterprise Server component could allow information disclosure and partial denial of service

    Broader source: Energy.gov [DOE]

    This advisory describes a security issue in the BlackBerry Administration API component. Successful exploitation of the vulnerability could result in information disclosure and partial denial of service (DoS). The BlackBerry Administration API is a BlackBerry Enterprise Server component that is installed on the server that hosts the BlackBerry Administration Service. The BlackBerry Administration API contains multiple web services that receive API requests from client applications. The BlackBerry Administration API then translates requests into a format that the BlackBerry Administration Service can process.

  18. PRECISE BLACK HOLE MASSES FROM MEGAMASER DISKS: BLACK HOLE-BULGE RELATIONS AT LOW MASS

    SciTech Connect (OSTI)

    Greene, Jenny E.; Peng, Chien Y.; Kim, Minjin; Kuo, Cheng-Yu; Braatz, James A.; Impellizzeri, C. M. Violette; Condon, James J.; Lo, K. Y.; Henkel, Christian; Reid, Mark J.

    2010-09-20

    The black hole (BH)-bulge correlations have greatly influenced the last decade of efforts to understand galaxy evolution. Current knowledge of these correlations is limited predominantly to high BH masses (M{sub BH{approx}}>10{sup 8} M{sub sun}) that can be measured using direct stellar, gas, and maser kinematics. These objects, however, do not represent the demographics of more typical L < L* galaxies. This study transcends prior limitations to probe BHs that are an order of magnitude lower in mass, using BH mass measurements derived from the dynamics of H{sub 2}O megamasers in circumnuclear disks. The masers trace the Keplerian rotation of circumnuclear molecular disks starting at radii of a few tenths of a pc from the central BH. Modeling of the rotation curves, presented by Kuo et al., yields BH masses with exquisite precision. We present stellar velocity dispersion measurements for a sample of nine megamaser disk galaxies based on long-slit observations using the B and C spectrograph on the Dupont telescope and the Dual Imaging Spectrograph on the 3.5 m telescope at Apache Point. We also perform bulge-to-disk decomposition of a subset of five of these galaxies with Sloan Digital Sky Survey imaging. The maser galaxies as a group fall below the M{sub BH}-{sigma}{sub *} relation defined by elliptical galaxies. We show, now with very precise BH mass measurements, that the low-scatter power-law relation between M{sub BH} and {sigma}{sub *} seen in elliptical galaxies is not universal. The elliptical galaxy M{sub BH}-{sigma}{sub *} relation cannot be used to derive the BH mass function at low mass or the zero point for active BH masses. The processes (perhaps BH self-regulation or minor merging) that operate at higher mass have not effectively established an M{sub BH}-{sigma}{sub *} relation in this low-mass regime.

  19. Instability of black hole formation in gravitational collapse

    SciTech Connect (OSTI)

    Joshi, Pankaj S.; Malafarina, Daniele

    2011-01-15

    We consider here the classic scenario given by Oppenheimer, Snyder, and Datt, for the gravitational collapse of a massive matter cloud, and examine its stability under the introduction of small tangential stresses. We show, by offering an explicit class of physically valid tangential stress perturbations, that an introduction of tangential pressure, however small, can qualitatively change the final fate of collapse from a black hole final state to a naked singularity. This shows instability of black hole formation in collapse and sheds important light on the nature of cosmic censorship hypothesis and its possible formulations. The key effect of these perturbations is to alter the trapped surface formation pattern within the collapsing cloud and the apparent horizon structure. This allows the singularity to be visible, and implications are discussed.

  20. Void morphology in polyethylene/carbon black composites

    SciTech Connect (OSTI)

    Marr, D.W.M.; Wartenberg, M.; Schwartz, K.B.

    1996-12-31

    A combination of small angle neutron scattering (SANS) and contrast matching techniques is used to determine the size and quantity of voids incorporated during fabrication of polyethylene/carbon black composites. The analysis used to extract void morphology from SANS data is based on the three-phase model of microcrack determination via small angle x-rayscattering (SAXS) developed by W.Wu{sup 12} and applied to particulate reinforced composites.

  1. Method of comparison equations for Schwarzschild black holes

    SciTech Connect (OSTI)

    Casadio, Roberto; Luzzi, Mattia

    2006-10-15

    We employ the method of comparison equations to study the propagation of a massless minimally coupled scalar field on the Schwarzschild background. In particular, we show that this method allows us to obtain explicit approximate expressions for the radial modes with energy below the peak of the effective potential which are fairly accurate over the whole region outside the horizon. This case can be of particular interest, for example, for the problem of black hole evaporation.

  2. ON THE EFFECT OF GIANT PLANETS ON THE SCATTERING OF PARENT BODIES OF IRON METEORITE FROM THE TERRESTRIAL PLANET REGION INTO THE ASTEROID BELT: A CONCEPT STUDY

    SciTech Connect (OSTI)

    Haghighipour, Nader; Scott, Edward R. D.

    2012-04-20

    In their model for the origin of the parent bodies of iron meteorites, Bottke et al. proposed differentiated planetesimals, formed in 1-2 AU during the first 1.5 Myr, as the parent bodies, and suggested that these objects and their fragments were scattered into the asteroid belt as a result of interactions with planetary embryos. Although viable, this model does not include the effect of a giant planet that might have existed or been growing in the outer regions. We present the results of a concept study where we have examined the effect of a planetary body in the orbit of Jupiter on the early scattering of planetesimals from the terrestrial region into the asteroid belt. We integrated the orbits of a large battery of planetesimals in a disk of planetary embryos and studied their evolutions for different values of the mass of the planet. Results indicate that when the mass of the planet is smaller than 10 M{sub Circled-Plus }, its effects on the interactions among planetesimals and planetary embryos are negligible. However, when the planet mass is between 10 and 50 M{sub Circled-Plus }, simulations point to a transitional regime with {approx}50 M{sub Circled-Plus} being the value for which the perturbing effect of the planet can no longer be ignored. Simulations also show that further increase of the mass of the planet strongly reduces the efficiency of the scattering of planetesimals from the terrestrial planet region into the asteroid belt. We present the results of our simulations and discuss their possible implications for the time of giant planet formation.

  3. Global solutions for higher-dimensional stretched small black holes

    SciTech Connect (OSTI)

    Chen, C.-M.; Gal'tsov, Dmitri V.; Ohta, Nobuyoshi; Orlov, Dmitry G.

    2010-01-15

    Small black holes in heterotic string theory have a vanishing horizon area at the supergravity level, but the horizon is stretched to the finite radius AdS{sub 2}xS{sup D-2} geometry once higher curvature corrections are turned on. This has been demonstrated to give good agreement with microscopic entropy counting. Previous considerations, however, were based on the classical local solutions valid only in the vicinity of the event horizon. Here we address the question of global existence of extremal black holes in the D-dimensional Einstein-Maxwell-Dilaton theory with the Gauss-Bonnet term introducing a variable dilaton coupling a as a parameter. We show that asymptotically flat black holes exist only in a bounded region of the dilaton couplings 0=}5 (but not for D=4) the allowed range of a includes the heterotic string values. For a>a{sub cr} numerical solutions meet weak naked singularities at finite radii r=r{sub cusp} (spherical cusps), where the scalar curvature diverges as |r-r{sub cusp}|{sup -1/2}. For D{>=}7 cusps are met in pairs, so that solutions can be formally extended to asymptotically flat infinity choosing a suitable integration variable. We show, however, that radial geodesics cannot be continued through the cusp singularities, so such a continuation is unphysical.

  4. Barrow Black Carbon Source and Impact Study Final Campaign Report

    SciTech Connect (OSTI)

    Barrett, Tate

    2014-07-01

    The goal of the Barrow Black Carbon Source and Impact (BBCSI) Study was to characterize the concentration and isotopic composition of carbonaceous atmospheric particulate matter (PM) at the Atmospheric Radiation Measurement site in Barrow, AK. The carbonaceous component was characterized via measurement of the organic and black carbon (OC and BC) components of the total PM. To facilitate complete characterization of the particulate matter, filter-based collections were used, including a medium volume PM2.5 sampler and a high volume PM10 sampler. Thirty-eight fine (PM2.5) and 49 coarse (PM10) particulate matter fractions were collected at weekly and bi-monthly intervals. The PM2.5 sampler operated with minimal maintenance during the 12 month campaign. The PM10 sampler used for the BBCSI used standard Tisch hi-vol motors which have a known lifetime of ~1 month under constant use; this necessitated monthly maintenance and it is suggested that the motors be upgraded to industrial blowers for future deployment in the Arctic. The BBCSI sampling campaign successfully collected and archived 87 ambient atmospheric particulate matter samples from Barrow, AK from July 2012 to June 2013. Preliminary analysis of the organic and black carbon concentrations has been completed. This campaign confirmed known trends of high BC lasting from the winter through to spring haze periods and low BC concentrations in the summer.

  5. Petroleum geology of Azov-Black Sea region

    SciTech Connect (OSTI)

    Lukin, A.; Trofimenko, G.

    1995-08-01

    The main features of tectonics, stratigraphy, paleogeography, lithology, hydrogeology, geothermics and hydrocarbon-bearingness of Azov-Black Sea Region are characterized on the basis of present-day data. Among the most prospective petroliferous complexes one ought to mention: Paleozoic (S - D - C{sub 1}) of Near-Dobrudga foredeep, Triassic - Jurassic of the Black Sea (shelf and continental slope); Lower Cretaceous of the various parts of the Region; Upper Cretaceous of the Black Sea shelf; Paleocene-Eocene of Azov Sea. In addition certain prospects are connected with Precambrian and Paleozoic basements within conjunction zone between Eastern-Europe platform and Scythian plate. Geodynamic evolution of the Region is considered with determination of tension and compression stages and characteristic of the main regularities of diapirs, mud volcanos, swells, horsts and grabens distribution. There determined the most interesting types of hydrocarbon traps connected with various tectonic forms, river and deltaic channels, bars, conturites, carbonate reefs, etc. Paleogeothermic and paleogeodynamic reconstructions allow to determine the main phases of oil and gas accumulation. The most prospective oil-gas-bearing zones and areas are mapped.

  6. Regular black holes: Electrically charged solutions, Reissner-Nordstroem outside a de Sitter core

    SciTech Connect (OSTI)

    Lemos, Jose P. S.; Zanchin, Vilson T.

    2011-06-15

    To have the correct picture of a black hole as a whole, it is of crucial importance to understand its interior. The singularities that lurk inside the horizon of the usual Kerr-Newman family of black hole solutions signal an endpoint to the physical laws and, as such, should be substituted in one way or another. A proposal that has been around for sometime is to replace the singular region of the spacetime by a region containing some form of matter or false vacuum configuration that can also cohabit with the black hole interior. Black holes without singularities are called regular black holes. In the present work, regular black hole solutions are found within general relativity coupled to Maxwell's electromagnetism and charged matter. We show that there are objects which correspond to regular charged black holes, whose interior region is de Sitter, whose exterior region is Reissner-Nordstroem, and the boundary between both regions is made of an electrically charged spherically symmetric coat. There are several types of solutions: regular nonextremal black holes with a null matter boundary, regular nonextremal black holes with a timelike matter boundary, regular extremal black holes with a timelike matter boundary, and regular overcharged stars with a timelike matter boundary. The main physical and geometrical properties of such charged regular solutions are analyzed.

  7. Black Holes in the Cosmos, the Lab, and in Fundamental Physics (3/3)

    ScienceCinema (OSTI)

    None

    2011-10-06

    Black holes present the extreme limits of physics. They are ubiquitous in the cosmos, and in some extra-dimensional scenarios they could be produced at colliders. They have also yielded a puzzle that challenges the foundations of physics. These talks will begin with an overview of the basics of black hole physics, and then briefly summarize some of the exciting developments with cosmic black holes. They will then turn to properties of quantum black holes, and the question of black hole production in high energy collisions, perhaps beginning with the LHC. I will then overview the apparent paradox emerging from Hawking's discovery of black hole evaporation, and what it could be teaching us about the foundations of quantum mechanics and gravity.

  8. Does the mass of a black hole decrease due to the accretion of phantom energy?

    SciTech Connect (OSTI)

    Gao Changjun; Chen Xuelei; Faraoni, Valerio; Shen Yougen

    2008-07-15

    According to Babichev et al., the accretion of a phantom test fluid onto a Schwarzschild black hole will induce the mass of the black hole to decrease, however the backreaction was ignored in their calculation. Using new exact solutions describing black holes in a background Friedmann-Robertson-Walker universe, we find that the physical black hole mass may instead increase due to the accretion of phantom energy. If this is the case, and the future universe is dominated by phantom dark energy, the black hole apparent horizon and the cosmic apparent horizon will eventually coincide and, after that, the black hole singularity will become naked in finite comoving time before the big rip occurs, violating the cosmic censorship conjecture.

  9. Black Holes in the Cosmos, the Lab, and in Fundamental Physics (2/3)

    ScienceCinema (OSTI)

    None

    2011-10-06

    Black holes present the extreme limits of physics. They are ubiquitous in the cosmos, and in some extra-dimensional scenarios they could be produced at colliders. They have also yielded a puzzle that challenges the foundations of physics. These talks will begin with an overview of the basics of black hole physics, and then briefly summarize some of the exciting developments with cosmic black holes. They will then turn to properties of quantum black holes, and the question of black hole production in high energy collisions, perhaps beginning with the LHC. I will then overview the apparent paradox emerging from Hawking's discovery of black hole evaporation, and what it could be teaching us about the foundations of quantum mechanics and gravity.

  10. Black Holes in the Cosmos, the Lab, and in Fundamental Physics (1/3)

    ScienceCinema (OSTI)

    None

    2011-10-06

    Black holes present the extreme limits of physics. They are ubiquitous in the cosmos, and in some extra-dimensional scenarios they could be produced at colliders. They have also yielded a puzzle that challenges the foundations of physics. These talks will begin with an overview of the basics of black hole physics, and then briefly summarize some of the exciting developments with cosmic black holes. They will then turn to properties of quantum black holes, and the question of black hole production in high energy collisions, perhaps beginning with the LHC. I will then overview the apparent paradox emerging from Hawking's discovery of black hole evaporation, and what it could be teaching us about the foundations of quantum mechanics and gravity.

  11. FIA-16-0040 - In the Matter of Kathy L. Black | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    0 - In the Matter of Kathy L. Black FIA-16-0040 - In the Matter of Kathy L. Black On June 27, 2016, OHA denied a Freedom of Information Act Appeal (FOIA) filed by Kathy L. Black (Appellant) of a determination issued by the DOE Office of Information Resources (OIR). In the Appeal, the Appellant challenged OIR's withholding under FOIA Exemption 5. OHA reviewed the withheld information and concluded that OIR properly withheld the information under Exemption 5's deliberative process privilege. OHA

  12. The Spitzer survey of interstellar clouds in the gould belt. VI. The Auriga-California molecular cloud observed with IRAC and MIPS

    SciTech Connect (OSTI)

    Broekhoven-Fiene, Hannah; Matthews, Brenda C.; Harvey, Paul M.; Gutermuth, Robert A.; Huard, Tracy L.; Miller, Jennifer F.; Tothill, Nicholas F. H.; Nutter, David; Bourke, Tyler L.; DiFrancesco, James; Jørgensen, Jes K.; Allen, Lori E.; Chapman, Nicholas L.; Dunham, Michael M.; Merín, Bruno; Terebey, Susan; Peterson, Dawn E.; and others

    2014-05-01

    We present observations of the Auriga-California Molecular Cloud (AMC) at 3.6, 4.5, 5.8, 8.0, 24, 70, and 160 μm observed with the IRAC and MIPS detectors as part of the Spitzer Gould Belt Legacy Survey. The total mapped areas are 2.5 deg{sup 2} with IRAC and 10.47 deg{sup 2} with MIPS. This giant molecular cloud is one of two in the nearby Gould Belt of star-forming regions, the other being the Orion A Molecular Cloud (OMC). We compare source counts, colors, and magnitudes in our observed region to a subset of the SWIRE data that was processed through our pipeline. Using color-magnitude and color-color diagrams, we find evidence for a substantial population of 166 young stellar objects (YSOs) in the cloud, many of which were previously unknown. Most of this population is concentrated around the LkHα 101 cluster and the filament extending from it. We present a quantitative description of the degree of clustering and discuss the relative fraction of YSOs in earlier (Class I and F) and later (Class II) classes compared to other clouds. We perform simple SED modeling of the YSOs with disks to compare the mid-IR properties to disks in other clouds and identify 14 classical transition disk candidates. Although the AMC is similar in mass, size, and distance to the OMC, it is forming about 15-20 times fewer stars.

  13. Development of transfer zones and location of oil and gas fields in frontal part of Bolivian Andean fold-and-thrust belt

    SciTech Connect (OSTI)

    Baby, P. ); Specht, M.; Colletta, B.; Letouzey, J. ); Mendez, E. ); Guillier, B. )

    1993-02-01

    The frontal part of the Bolivian Andean thrust belt consists of a thick series of paleozoic to cenozoic sedimentary rocks (5 to 8 km thick) which are folded and thrusted towards the east on a sole thrust at the base of paleozoic series. The front of this tectonic wedge is characterized by transfer zones of various scales and geometries. The main oil and gas fields are located in these transfer zones. A study realized from YPFB (Yacimientos Petroliferos Fiscales Bolivianos) seismic data shows that in all the cases, the deformation is controlled by the geometry and thickness variations of the paleozoic basin. The most spectacular transfer zone appears at the bolivian orocline scale and corresponds to the famous bending of the andean thrust front close to Santa Cruz. More to the south (19 to 22[degrees] S) the southern foreland fold and thrust belt is characterized by a set of local right lateral offset transfer zones ([open quotes]en echellon[close quotes] folds). The difference of geometry and scale of the transfer zones seems to be related to the variation of the angle value between the shortening direction and the direction of the paleozoic basin borders. In order to test our interpretation, to constrain the boundary conditions and to study the thrust propagation sequence, we performed a set of analog model experiments whose 3D visualization was analyzed by computerized X-ray tomography.

  14. THE HERSCHEL AND JCMT GOULD BELT SURVEYS: CONSTRAINING DUST PROPERTIES IN THE PERSEUS B1 CLUMP WITH PACS, SPIRE, AND SCUBA-2

    SciTech Connect (OSTI)

    Sadavoy, S. I.; Di Francesco, J.; Johnstone, D.; Fallscheer, C.; Matthews, B.; Currie, M. J.; Jenness, T.; Drabek, E.; Hatchell, J.; Nutter, D.; Andre, Ph.; Hennemann, M.; Hill, T.; Koenyves, V.; Benedettini, M.; Bernard, J.-P.; Duarte-Cabral, A.; Friesen, R.; Greaves, J.; Collaboration: JCMT and Herschel Gould Belt Survey teams; and others

    2013-04-20

    We present Herschel observations from the Herschel Gould Belt Survey and SCUBA-2 science verification observations from the JCMT Gould Belt Survey of the B1 clump in the Perseus molecular cloud. We determined the dust emissivity index using four different techniques to combine the Herschel PACS+SPIRE data at 160-500 {mu}m with the SCUBA-2 data at 450 {mu}m and 850 {mu}m. Of our four techniques, we found that the most robust method was filtering out the large-scale emission in the Herschel bands to match the spatial scales recovered by the SCUBA-2 reduction pipeline. Using this method, we find {beta} Almost-Equal-To 2 toward the filament region and moderately dense material and lower {beta} values ({beta} {approx}> 1.6) toward the dense protostellar cores, possibly due to dust grain growth. We find that {beta} and temperature are more robust with the inclusion of the SCUBA-2 data, improving estimates from Herschel data alone by factors of {approx}2 for {beta} and by {approx}40% for temperature. Furthermore, we find core mass differences of {approx}< 30% compared to Herschel-only estimates with an adopted {beta} = 2, highlighting the necessity of long-wavelength submillimeter data for deriving accurate masses of prestellar and protostellar cores.

  15. Searching for mini black holes signatures in cosmic rays air shower

    SciTech Connect (OSTI)

    Lamri, S.; Kalli, S.; Mimouni, J.

    2012-06-27

    Theories with extra dimensions at low Planck scale, offer the exciting possibility of mini black holes production in ultra high-energy particles interactions. In particular, cosmic neutrinos interaction can produce black holes deep in the Earth's atmosphere. These mini black holes then decay and produce 'characteristic' air showers. In this paper, we examine the properties of the mini black holes (mBH) air showers and compare them to the standard model (mSM) ones. We point out to some possible criteria that help distinguishing mBH air showers.

  16. Surface geometry of a rotating black hole in a magnetic field...

    Office of Scientific and Technical Information (OSTI)

    Subject: 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BLACK HOLES; KERR FIELD; ROTATION; DIFFERENTIAL GEOMETRY; EINSTEIN-MAXWELL EQUATIONS; EQUATIONS; FIELD EQUATIONS; ...

  17. Five-dimensional black strings in Einstein-Gauss-Bonnet gravity

    SciTech Connect (OSTI)

    Kobayashi, Tsutomu; Tanaka, Takahiro

    2005-04-15

    We consider black-string-type solutions in five-dimensional Einstein-Gauss-Bonnet gravity. Numerically constructed solutions under static, axially symmetric and translationally invariant metric ansatz are presented. The solutions are specified by two asymptotic charges: mass of a black string and a scalar charge associated with the radion part of the metric. Regular black string solutions are found if and only if the two charges satisfy a fine-tuned relation, and otherwise the spacetime develops a singular event horizon or a naked singularity. We can also generate bubble solutions from the black strings by using a double Wick rotation.

  18. Navy legend Carl Brashear speaks at JLab's Black History Month event |

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Jefferson Lab Navy legend Carl Brashear speaks at JLab's Black History Month event Carl Brashear poster Carl Brashear will speak at JLab's Black History Month event on Wednesday, February 19 at 2p.m. Navy legend Carl Brashear speaks at JLab's Black History Month event February 6, 2003 U.S. Naval legend Carl Brashear will be at Jefferson Lab on Wednesday, February 19, as the Lab's guest speaker for Black History Month Directions to the Lab Enter through Onnes Dr. from Jefferson Ave. Anyone 16

  19. Generalized uncertainty principle in f(R) gravity for a charged black hole

    SciTech Connect (OSTI)

    Said, Jackson Levi; Adami, Kristian Zarb

    2011-02-15

    Using f(R) gravity in the Palatini formularism, the metric for a charged spherically symmetric black hole is derived, taking the Ricci scalar curvature to be constant. The generalized uncertainty principle is then used to calculate the temperature of the resulting black hole; through this the entropy is found correcting the Bekenstein-Hawking entropy in this case. Using the entropy the tunneling probability and heat capacity are calculated up to the order of the Planck length, which produces an extra factor that becomes important as black holes become small, such as in the case of mini-black holes.

  20. V-158: BlackBerry Tablet OS Flash Player Multiple Vulnerabilities

    Broader source: Energy.gov [DOE]

    Multiple vulnerabilities have been reported in BlackBerry Tablet OS, which can be exploited by malicious people to bypass certain security restrictions and compromise a user's system.

  1. Climate Impacts of Atmospheric Sulfate and Black Carbon Aerosols

    SciTech Connect (OSTI)

    Qian, Yun; Song, Qingyuan; Menon, Surabi; Yu, Shaocai; Liu, Shaw C.; Shi, Guangyu; Leung, Lai R.; Luo, Yunfeng

    2008-09-19

    Although the global average surface temperature has increased by about 0.6°C during the last century (IPCC, 2001), some regions such as East Asia, Eastern North America, and Western Europe have cooled rather than warmed during the past decades (Jones, 1988; Qian and Giorgi, 2000). Coherent changes at the regional scale may reflect responses to different climate forcings that need to be understood in order to predict the future net climate response at the global and regional scales under different emission scenarios. Atmospheric aerosols play an important role in global climate change (IPCC 2001). They perturb the earth’s radiative budget directly by scattering and absorbing solar and long wave radiation, and indirectly by changing cloud reflectivity, lifetime, and precipitation efficiency via their role as cloud condensation nuclei. Because aerosols have much shorter lifetime (days to weeks) compared to most greenhouse gases, they tend to concentrate near their emission sources and distribute very unevenly both in time and space. This non-uniform distribution of aerosols, in conjunction with the greenhouse effect, may lead to differential net heating in some areas and net cooling in others (Penner et al. 1994). Sulfate aerosols come mainly from the oxidation of sulfur dioxide (SO2) emitted from fossil fuel burning. Black carbon aerosols are directly emitted during incomplete combustion of biomass, coal, and diesel derived sources. Due to the different optical properties, sulfate and black carbon affect climate in different ways. Because of the massive emissions of sulfur and black carbon that accompany the rapid economic expansions in East Asia, understanding the effects of aerosols on climate is particularly important scientifically and politically in order to develop adaptation and mitigation strategies.

  2. Barrow Black Carbon Source and Impact Study Final Campaign Report

    SciTech Connect (OSTI)

    Barrett, Tate

    2014-07-01

    The goal of the Barrow Black Carbon Source and Impact campaign was to characterize the concentration and isotopic composition of carbonaceous atmospheric particulate matter (PM) at the Atmospheric Radiation Measurement (ARM) Climate Research Facility site in Barrow, Alaska. The carbonaceous component was characterized by measuring the organic and black carbon (OC and BC) components of the total PM. To facilitate complete characterization of the PM, filter-based collections were used, including a medium volume PM2.5 sampler and a high volume PM10 sampler. Thirty-eight fine PM fractions (PM2.5) and 49 coarse (PM10) PM fractions were collected at weekly and bi-monthly intervals. The PM2.5 sampler operated with minimal maintenance during the 12 month campaign. The PM10 sampler used for the Barrow Black Carbon Source and Impact (BBCSI) study used standard Tisch “hi-vol” motors that have a known lifetime of approximately 1 month under constant use; this necessitated monthly maintenance, and it is suggested that, for future deployment in the Arctic, the motors be upgraded to industrial blowers. The BBCSI sampling campaign successfully collected and archived 87 ambient atmospheric PM samples from Barrow, Alaska, from July 2012 to June 2013. Preliminary analysis of the OC and BC concentrations has been completed. This campaign confirmed known trends of high BC lasting from the winter through to spring haze periods and low BC concentrations in the summer. However, the annual OC concentrations had a very different seasonal pattern with the highest concentrations during the summer, lowest concentrations during the fall, and increased concentrations during the winter and spring (Figure 1).

  3. Minimum length, extra dimensions, modified gravity and black hole remnants

    SciTech Connect (OSTI)

    Maziashvili, Michael

    2013-03-01

    We construct a Hilbert space representation of minimum-length deformed uncertainty relation in presence of extra dimensions. Following this construction, we study corrections to the gravitational potential (back reaction on gravity) with the use of correspondingly modified propagator in presence of two (spatial) extra dimensions. Interestingly enough, for r?0 the gravitational force approaches zero and the horizon for modified Schwarzschild-Tangherlini space-time disappears when the mass approaches quantum-gravity energy scale. This result points out to the existence of zero-temperature black hole remnants in ADD brane-world model.

  4. Black hole temperature: Minimal coupling vs conformal coupling

    SciTech Connect (OSTI)

    Fazel, Mohamadreza; Mirza, Behrouz; Mansoori, Seyed Ali Hosseini

    2014-05-15

    In this article, we discuss the propagation of scalar fields in conformally transformed spacetimes with either minimal or conformal coupling. The conformally coupled equation of motion is transformed into a one-dimensional Schrödinger-like equation with an invariant potential under conformal transformation. In a second stage, we argue that calculations based on conformal coupling yield the same Hawking temperature as those based on minimal coupling. Finally, it is conjectured that the quasi normal modes of black holes are invariant under conformal transformation.

  5. Entropy localization and extensivity in the semiclassical black hole evaporation

    SciTech Connect (OSTI)

    Casini, H.

    2009-01-15

    I aim to quantify the distribution of information in the Hawking radiation and inside the black hole in the semiclassical evaporation process. The structure of relativistic quantum field theory does not allow one to define a localized entropy unambiguously, but rather forces one to consider the shared information (mutual information) between two different regions of space-time. Using this tool, I first show that the entropy of a thermal gas at the Unruh temperature underestimates the actual amount of (shared) information present in a region of the Rindler space. Then, I analyze the mutual information between the black hole and the late time radiation region. A well-known property of the entropy implies that this is monotonically increasing with time. This means that in the semiclassical picture it is not possible to recover the eventual purity of the initial state in the final Hawking radiation through subtle correlations established during the whole evaporation period, no matter the interactions present in the theory. I find extensivity of the entropy as a consequence of a reduction to a two dimensional conformal problem in a simple approximation. However, the extensivity of information in the radiation region in a full four dimensional calculation seems not to be guaranteed on general grounds. I also analyze the localization of shared information inside the black hole finding that a large amount of it is contained in a small, approximately flat region of space-time near the point where the horizon begins. This gives place to large violations of the entropy bounds. I show that this problem is not eased by backscattering effects and argue that a breaking of conformal invariance is necessary to delocalize the entropy. Finally, I indicate that the mutual information could lead to a way to understand the Bekenstein-Hawking black hole entropy which does not require a drastic reduction in degrees of freedom in order to regulate the entanglement entropy. On the contrary

  6. Primordial Black Holes: Observational characteristics of the final evaporation

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ukwatta, T. N.; Stump, D. R.; Linnemann, J. T.; MacGibbon, J. H.; Marinelli, S. S.; Yapici, T.; Tollefson, K.

    2016-07-01

    For many early universe theories predict the creation of Primordial Black Holes (PBHs). PBHs could have masses ranging from the Planck mass to 105 solar masses or higher depending on the size of the universe at formation. A Black Hole (BH) has a Hawking temperature which is inversely proportional to its mass. Hence a sufficiently small BH will quasi-thermally radiate particles at an ever-increasing rate as emission lowers its mass and raises its temperature. Moreover, the final moments of this evaporation phase should be explosive and its description is dependent on the particle physics model. In this work we investigatemore » the final few seconds of BH evaporation, using the Standard Model and incorporating the most recent Large Hadron Collider (LHC) results, and provide a new parameterization for the instantaneous emission spectrum. We calculate for the first time energy-dependent PBH burst light curves in the GeV/TeV energy range. Moreover, we explore PBH burst search methods and potential observational PBH burst signatures. We have found a unique signature in the PBH burst light curves that may be detectable by GeV/TeV gamma-ray observatories such as the High Altitude Water Cerenkov (HAWC) observatory. Finally, the implications of beyond the Standard Model theories on the PBH burst observational characteristics are also discussed, including potential sensitivity of the instantaneous photon detection rate to a squark threshold in the 5–10 TeV range.« less

  7. CALIBRATING C-IV-BASED BLACK HOLE MASS ESTIMATORS

    SciTech Connect (OSTI)

    Park, Daeseong; Woo, Jong-Hak; Shin, Jaejin [Astronomy Program, Department of Physics and Astronomy, Seoul National University, Seoul 151-742 (Korea, Republic of); Denney, Kelly D., E-mail: pds2001@astro.snu.ac.kr, E-mail: woo@astro.snu.ac.kr, E-mail: jjshin@astro.snu.ac.kr, E-mail: kelly@dark-cosmology.dk [Dark Cosmology Centre, Niels Bohr Institute, Juliane Maries Vej 30, DK-2100 Copenhagen O (Denmark)

    2013-06-20

    We present the single-epoch black hole mass estimators based on the C IV {lambda}1549 broad emission line, using the updated sample of the reverberation-mapped active galactic nuclei and high-quality UV spectra. By performing multi-component spectral fitting analysis, we measure the C IV line widths (FWHM{sub C{sub IV}} and line dispersion, {sigma}{sub C{sub IV}}) and the continuum luminosity at 1350 A (L{sub 1350}) to calibrate the C-IV-based mass estimators. By comparing with the H{beta} reverberation-based masses, we provide new mass estimators with the best-fit relationships, i.e., M{sub BH}{proportional_to}L{sub 1350}{sup 0.50{+-}0.07}{sigma}{sub C{sub IV}{sup 2}} and M{sub BH}{proportional_to}L{sub 1350}{sup 0.52{+-}0.09} FWHM{sub C{sub IV}{sup 0.56{+-}0.48}}. The new C-IV-based mass estimators show significant mass-dependent systematic difference compared to the estimators commonly used in the literature. Using the published Sloan Digital Sky Survey QSO catalog, we show that the black hole mass of high-redshift QSOs decreases on average by {approx}0.25 dex if our recipe is adopted.

  8. GRAVITATIONAL WAVE SIGNATURES IN BLACK HOLE FORMING CORE COLLAPSE

    SciTech Connect (OSTI)

    Cerd-Durn, Pablo; DeBrye, Nicolas; Aloy, Miguel A.; Font, Jos A.; Obergaulinger, Martin

    2013-12-20

    We present general relativistic numerical simulations of collapsing stellar cores. Our initial model consists of a low metallicity rapidly-rotating progenitor which is evolved in axisymmetry with the latest version of our general relativistic code CoCoNuT, which allows for black hole formation and includes the effects of a microphysical equation of state (LS220) and a neutrino leakage scheme to account for radiative losses. The motivation of our study is to analyze in detail the emission of gravitational waves in the collapsar scenario of long gamma-ray bursts. Our simulations show that the phase during which the proto-neutron star (PNS) survives before ultimately collapsing to a black hole is particularly optimal for gravitational wave emission. The high-amplitude waves last for several seconds and show a remarkable quasi-periodicity associated with the violent PNS dynamics, namely during the episodes of convection and the subsequent nonlinear development of the standing-accretion shock instability (SASI). By analyzing the spectrogram of our simulations we are able to identify the frequencies associated with the presence of g-modes and with the SASI motions at the PNS surface. We note that the gravitational waves emitted reach large enough amplitudes to be detected with third-generation detectors such as the Einstein Telescope within a Virgo Cluster volume at rates ? 0.1yr{sup 1}.

  9. Effects of intermediate mass black holes on nuclear star clusters

    SciTech Connect (OSTI)

    Mastrobuono-Battisti, Alessandra; Perets, Hagai B.; Loeb, Abraham

    2014-11-20

    Nuclear star clusters (NSCs) are dense stellar clusters observed in galactic nuclei, typically hosting a central massive black hole. Here we study the possible formation and evolution of NSCs through the inspiral of multiple star clusters hosting intermediate mass black holes (IMBHs). Using an N-body code, we examine the dynamics of the IMBHs and their effects on the NSC. We find that IMBHs inspiral to the core of the newly formed NSC and segregate there. Although the IMBHs scatter each other and the stars, none of them is ejected from the NSC. The IMBHs are excited to high eccentricities and their radial density profile develops a steep power-law cusp. The stars also develop a power-law cusp (instead of the central core that forms in their absence), but with a shallower slope. The relaxation rate of the NSC is accelerated due to the presence of IMBHs, which act as massive perturbers. This in turn fills the loss cone and boosts the tidal disruption rate of stars both by the MBH and the IMBHs to a value excluded by rate estimates based on current observations. Rate estimates of tidal disruptions can therefore provide a cumulative constraint on the existence of IMBHs in NSCs.

  10. Strengthening Our Partnerships with Historically Black Colleges and Universities

    Broader source: Energy.gov [DOE]

    Secretary Chu meets with Annie Whatley, Acting Chief of Staff in the Office of Economic Impact and Diversity, and Dr. William Harvey. Last February, President Obama renewed the White House Initiative on Historically Black Colleges and Universities to encourage collaboration between government agencies, educational associations, philanthropic organizations, the private sector and others to increase the capacity of HBCUs to provide high-quality education to a greater number of students.  The Department of Energy is committed to supporting education at HBCUs and has partnered with HBCUs on a variety of projects. As part of that commitment, today I met with Dr. William Harvey, Chairman of the President’s Board of Advisors on Historically Black Colleges and Universities and President of Hampton University, as well as Langston University President JoAnn Haysbert and Morgan State University President David Wilson. The presidents and I discussed how the Department can better engage HBCUs in our science and laboratory projects, and what lessons we can learn from the many ongoing and successful partnerships we have in place.

  11. Hawking radiation of scalar particles from accelerating and rotating black holes

    SciTech Connect (OSTI)

    Gillani, Usman A.; Rehman, Mudassar; Saifullah, K. E-mail: mudassar051@yahoo.com

    2011-06-01

    Hawking radiation of uncharged and charged scalar particles from accelerating and rotating black holes is studied. We calculate the tunneling probabilities of these particles from the rotation and acceleration horizons of these black holes. Using this method we recover the correct Hawking temperature as well.

  12. AmeriFlux CA-Qfo Quebec - Eastern Boreal, Mature Black Spruce

    SciTech Connect (OSTI)

    Margolis, Hank A.

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site CA-Qfo Quebec - Eastern Boreal, Mature Black Spruce. Site Description - 49.69247° N / 74.34204° W, elevation of 387 mm, 90 - 100 yr old Black Spruce, Jack Pine, feather moss

  13. X-ray technology behind NASA's black-hole hunter (NuSTAR)

    ScienceCinema (OSTI)

    Craig, Bill

    2014-05-22

    Livermore Lab astrophysicist Bill Craig describes his team's role in developing X-ray imaging technology for the NASA Nuclear Spectroscopic Telescope Array (NuSTAR) mission. The black-hole-hunting spacecraft bagged its first 10 supermassive black holes this week

  14. X-ray technology behind NASA's black-hole hunter (NuSTAR)

    SciTech Connect (OSTI)

    Craig, Bill

    2013-09-10

    Livermore Lab astrophysicist Bill Craig describes his team's role in developing X-ray imaging technology for the NASA Nuclear Spectroscopic Telescope Array (NuSTAR) mission. The black-hole-hunting spacecraft bagged its first 10 supermassive black holes this week

  15. Lithospheric flexure and composite tectonic loads in the foreland of the Marathon orogenic belt: Permian Basin, west Texas and southern New Mexico

    SciTech Connect (OSTI)

    Yang, Kenn Ming; Dorobek, S. . Dept. of Geology)

    1992-01-01

    Lithospheric flexure caused by loading of orogenic belts is regarded as the main process that produces subsidence in foreland basins. However in some foreland areas, subsidence may be affected by synorogenic foreland uplifts that act as additional loads. The Permian Basin is located in the foreland area of the late Paleozoic Marathon orogenic belt (Mob). The Permian Basin consists of several sub-basins that are separated by several structurally complex uplifts. Uplift of the Central Basin Platform (CBP) and subsidence in adjacent basins were coeval with final stages of deformation in the Marathon orogen. The CBP is oriented at high angles to the Marathon orogen and consists of several blocks arranged in an en echelon pattern. Data suggest that uplift of the CBP was affected by clockwise rotation of crustal blocks between NNW-SSE trending boundary faults. Although both the Delaware Basin (DB) and Val Verde Basin (VVB) are adjacent to the Mob, the synorogenic geometries of these basins are different. The VVB has a typical flexural profile that apparently is due to loading of the Marathon orogen. However, the flexural profile becomes narrower and deeper toward the western end of the VVB where the basin is bordered by the southernmost block of the CBP. In contrast, synorogenic DB profiles have composite wavelengths which show maximum deflection next to the Mob and toward the uplifted blocks of the CBP. This suggests that synorogenic subsidence of the DB was affected by loading of the CBP. In addition, the loading geometry across the uplifted CBP is asymmetric, with greater uplift and basement shortening on the western side of the CBP and less uplift and basement shortening on the eastern side. This may explain greater synorogenic subsidence in the DB than the Midland Basin.

  16. Historically Black Colleges and Universities (HBCU) Solar Radiation Monitoring Network

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    The Historically Black Colleges and Universities (HBCU) Solar Radiation Monitoring Network operated from November 1985 through December 1996. The six-station network provided 5-minute averaged measurements of global and diffuse horizontal solar irradiance. The data were processed at the National Renewable Energy Laboratory (NREL) to improve the assessment of the solar radiation resources in the southeastern United States. Three of the stations also measured the direct-normal solar irradiance with a pyrheliometer mounted in an automatic sun tracker. All data are archived in the Standard Broadband Format (SBF) with quality-assessment indicators. Monthly data summaries and plots are also available for each month. In January 1997 the HBCU sites became part of the CONFRRM solar monitoring network.

  17. The genome of black cottonwood, Populus trichocarpa (Torr.&Gray)

    SciTech Connect (OSTI)

    Tuskan, G.A.; DiFazio, S.; Jansson, S.; Bohlmann, J.; Grigoriev,I.; Hellsten, U.; Putnam, N.; Ralph, S.; Rombauts, S.; Salamov, A.; Schein, J.; Sterck, L.; Aerts, A.; Bhalerao, R.R.; Bhalerao, R.P.; Blaudez, D.; Boerjan, W.; Brun, A.; Brunner, A.; Busov, V.; Campbell, M.; Carlson, J.; Chalot, M.; Chapman, J.; Chen, G.-L.; Cooper, D.; Coutinho,P.M.; Couturier, J.; Covert, S.; Cronk, Q.; Cunningham, R.; Davis, J.; Degroeve, S.; Dejardin, A.; dePamphillis, C.; Detter, J.; Dirks, B.; Dubchak, I.; Duplessis, S.; Ehiting, J.; Ellis, B.; Gendler, K.; Goodstein, D.; Gribskov, M.; Grimwood, J.; Groover, A.; Gunter, L.; Hamberger, B.; Heinze, B.; Helariutta, Y.; Henrissat, B.; Holligan, D.; Holt, R.; Huang, W.; Islam-Faridi, N.; Jones, S.; Jones-Rhoades, M.; Jorgensen, R.; Joshi, C.; Kangasjarvi, J.; Karlsson, J.; Kelleher, C.; Kirkpatrick, R.; Kirst, M.; Kohler, A.; Kalluri, U.; Larimer, F.; Leebens-Mack, J.; Leple, J.-C.; Locascio, P.; Lou, Y.; Lucas, S.; Martin,F.; Montanini, B.; Napoli, C.; Nelson, D.R.; Nelson, D.; Nieminen, K.; Nilsson, O.; Peter, G.; Philippe, R.; Pilate, G.; Poliakov, A.; Razumovskaya, J.; Richardson, P.; Rinaldi, C.; Ritland, K.; Rouze, P.; Ryaboy, D.; Schmutz, J.; Schrader, J.; Segerman, B.; Shin, H.; Siddiqui,A.; Sterky, F.; Terry, A.; Tsai, C.; Uberbacher, E.; Unneberg, P.; Vahala, J.; Wall, K.; Wessler, S.; Yang, G.; Yin, T.; Douglas, C.; Marra,M.; Sandberg, G.; Van der Peer, Y.; Rokhsar, D.

    2006-09-01

    We report the draft genome of the black cottonwood tree, Populus trichocarpa. Integration of shotgun sequence assembly with genetic mapping enabled chromosome-scale reconstruction of the genome. Over 45,000 putative protein-coding genes were identified. Analysis of the assembled genome revealed a whole-genome duplication event, with approximately 8,000 pairs of duplicated genes from that event surviving in the Populus genome. A second, older duplication event is indistinguishably coincident with the divergence of the Populus and Arabidopsis lineages. Nucleotide substitution, tandem gene duplication and gross chromosomal rearrangement appear to proceed substantially slower in Populus relative to Arabidopsis. Populus has more protein-coding genes than Arabidopsis, ranging on average between 1.4-1.6 putative Populus homologs for each Arabidopsis gene. However, the relative frequency of protein domains in the two genomes is similar. Overrepresented exceptions in Populus include genes associated with disease resistance, meristem development, metabolite transport and lignocellulosic wall biosynthesis.

  18. Recoiling supermassive black holes: a search in the nearby universe

    SciTech Connect (OSTI)

    Lena, D.; Robinson, A.; Axon, D. J.; Merritt, D.; Marconi, A.; Capetti, A.; Batcheldor, D.

    2014-11-10

    The coalescence of a binary black hole can be accompanied by a large gravitational recoil due to anisotropic emission of gravitational waves. A recoiling supermassive black hole (SBH) can subsequently undergo long-lived oscillations in the potential well of its host galaxy, suggesting that offset SBHs may be common in the cores of massive ellipticals. We have analyzed Hubble Space Telescope archival images of 14 nearby core ellipticals, finding evidence for small (? 10 pc) displacements between the active galactic nucleus (AGN; the location of the SBH) and the center of the galaxy (the mean photocenter) in 10 of them. Excluding objects that may be affected by large-scale isophotal asymmetries, we consider six galaxies to have detected displacements, including M87, where a displacement was previously reported by Batcheldor et al. In individual objects, these displacements can be attributed to residual gravitational recoil oscillations following a major or minor merger within the last few gigayears. For plausible merger rates, however, there is a high probability of larger displacements than those observed, if SBH coalescence took place in these galaxies. Remarkably, the AGN-photocenter displacements are approximately aligned with the radio source axis in four of the six galaxies with displacements, including three of the four having relatively powerful kiloparsec-scale jets. This suggests intrinsic asymmetries in radio jet power as a possible displacement mechanism, although approximate alignments are also expected for gravitational recoil. Orbital motion in SBH binaries and interactions with massive perturbers can produce the observed displacement amplitudes but do not offer a ready explanation for the alignments.

  19. RECOILING SUPERMASSIVE BLACK HOLES IN SPIN-FLIP RADIO GALAXIES

    SciTech Connect (OSTI)

    Liu, F. K.; Wang Dong; Chen Xian

    2012-02-20

    Numerical relativity simulations predict that coalescence of supermassive black hole (SMBH) binaries leads not only to a spin flip but also to a recoiling of the merger remnant SMBHs. In the literature, X-shaped radio sources are popularly suggested to be candidates for SMBH mergers with spin flip of jet-ejecting SMBHs. Here we investigate the spectral and spatial observational signatures of the recoiling SMBHs in radio sources undergoing black hole spin flip. Our results show that SMBHs in most spin-flip radio sources have mass ratio q {approx}> 0.3 with a minimum possible value q{sub min} {approx_equal} 0.05. For major mergers, the remnant SMBHs can get a kick velocity as high as 2100 km s{sup -1} in the direction within an angle {approx}< 40 Degree-Sign relative to the spin axes of remnant SMBHs, implying that recoiling quasars are biased to be with high Doppler-shifted broad emission lines while recoiling radio galaxies are biased to large apparent spatial off-center displacements. We also calculate the distribution functions of line-of-sight velocity and apparent spatial off-center displacements for spin-flip radio sources with different apparent jet reorientation angles. Our results show that the larger the apparent jet reorientation angle is, the larger the Doppler-shifting recoiling velocity and apparent spatial off-center displacement will be. We investigate the effects of recoiling velocity on the dust torus in spin-flip radio sources and suggest that recoiling of SMBHs would lead to 'dust-poor' active galactic nuclei. Finally, we collect a sample of 19 X-shaped radio objects and for each object give the probability of detecting the predicted signatures of recoiling SMBH.

  20. Constraining the spin and the deformation parameters from the black hole shadow

    SciTech Connect (OSTI)

    Tsukamoto, Naoki; Li, Zilong; Bambi, Cosimo E-mail: zilongli@fudan.edu.cn

    2014-06-01

    Within 5–10 years, very-long baseline interferometry (VLBI) facilities will be able to directly image the accretion flow around SgrA*, the super-massive black hole candidate at the center of the Galaxy, and observe the black hole ''shadow''. In 4-dimensional general relativity, the no-hair theorem asserts that uncharged black holes are described by the Kerr solution and are completely specified by their mass M and by their spin parameter a. In this paper, we explore the possibility of distinguishing Kerr and Bardeen black holes from their shadow. In Hioki and Maeda (2009), under the assumption that the background geometry is described by the Kerr solution, the authors proposed an algorithm to estimate the value of a/M by measuring the distortion parameter δ, an observable quantity that characterizes the shape of the shadow. Here, we try to extend their approach. Since the Hioki-Maeda distortion parameter is degenerate with respect to the spin and possible deviations from the Kerr solution, one has to measure another quantity to test the Kerr black hole hypothesis. We study a few possibilities. We find that it is extremely difficult to distinguish Kerr and Bardeen black holes from the sole observation of the shadow, and out of reach for the near future. The combination of the measurement of the shadow with possible accurate radio observations of a pulsar in a compact orbit around SgrA* could be a more promising strategy to verify the Kerr black hole paradigm.

  1. Sulfide-Driven Arsenic Mobilization from Arsenopyrite and Black Shale Pyrite

    SciTech Connect (OSTI)

    Zhu, W.; Young, L; Yee, N; Serfes, M; Rhine, E; Reinfelder, J

    2008-01-01

    We examined the hypothesis that sulfide drives arsenic mobilization from pyritic black shale by a sulfide-arsenide exchange and oxidation reaction in which sulfide replaces arsenic in arsenopyrite forming pyrite, and arsenide (As-1) is concurrently oxidized to soluble arsenite (As+3). This hypothesis was tested in a series of sulfide-arsenide exchange experiments with arsenopyrite (FeAsS), homogenized black shale from the Newark Basin (Lockatong formation), and pyrite isolated from Newark Basin black shale incubated under oxic (21% O2), hypoxic (2% O2, 98% N2), and anoxic (5% H2, 95% N2) conditions. The oxidation state of arsenic in Newark Basin black shale pyrite was determined using X-ray absorption-near edge structure spectroscopy (XANES). Incubation results show that sulfide (1 mM initial concentration) increases arsenic mobilization to the dissolved phase from all three solids under oxic and hypoxic, but not anoxic conditions. Indeed under oxic and hypoxic conditions, the presence of sulfide resulted in the mobilization in 48 h of 13-16 times more arsenic from arsenopyrite and 6-11 times more arsenic from isolated black shale pyrite than in sulfide-free controls. XANES results show that arsenic in Newark Basin black shale pyrite has the same oxidation state as that in FeAsS (-1) and thus extend the sulfide-arsenide exchange mechanism of arsenic mobilization to sedimentary rock, black shale pyrite. Biologically active incubations of whole black shale and its resident microorganisms under sulfate reducing conditions resulted in sevenfold higher mobilization of soluble arsenic than sterile controls. Taken together, our results indicate that sulfide-driven arsenic mobilization would be most important under conditions of redox disequilibrium, such as when sulfate-reducing bacteria release sulfide into oxic groundwater, and that microbial sulfide production is expected to enhance arsenic mobilization in sedimentary rock aquifers with major pyrite-bearing, black

  2. Formation of carbon black as a byproduct of pyrolysis of light hydrocarbons in plasma jet

    SciTech Connect (OSTI)

    Chen, H.G.; Zhang, X.B.; Li, F.; Xie, K.C.; Dai, B.; Fan, Y.S.

    1997-12-31

    The light hydrocarbons undergo a complex reaction of flash hydropyrolysis in a DC arc H{sub 2}/Ar plasma jet at atmospheric pressure and average temperatures between 1,500 K and 4,000 K. The raw material was LPG. Acetylene is the major product. Carbon black is a byproduct. Carbon black is characterized with XRD, TEM, and adsorption-and-desorption of liquid nitrogen, respectively. The present work proposes to use the plasma process to replace the classical thermal process in order to produce acetylene directly from LPG with carbon black being a byproduct.

  3. FIA-16-0034 - In the Matter of Leo Conor Black | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    4 - In the Matter of Leo Conor Black FIA-16-0034 - In the Matter of Leo Conor Black On June 13, 2016, OHA denied a FOIA Appeal filed by Leo Conor Black from a determination issued by the Office of Information Resources (OIR) of the Department of Energy. In the Appeal, the Appellant challenged the adequacy of OIR's search for responsive documents. OHA found, however, that OIR conducted a search reasonably calculated to uncover the materials sought by the Appellant. FIA-16-0034.pdf (139.28 KB)

  4. Legendary Tuskegee Airmen to Speak at Jefferson Lab's Black History Month

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Event | Jefferson Lab Legendary Tuskegee Airmen to Speak at Jefferson Lab's Black History Month Event Legendary Tuskegee Airmen to Speak at Jefferson Lab's Black History Month Event February 3, 2004 Three members of the legendary, World War II era Tuskegee Airmen will speak at Jefferson Lab's Black History Month celebration at 2:30 p.m. on Thursday, Feb. 19. The public is invited to the event. The program will start with footage from the 1996 movie based on the true story of the Tuskegee

  5. General Nonextremal Rotating Black Holes in Minimal Five-Dimensional Gauged Supergravity

    SciTech Connect (OSTI)

    Chong, Z.-W.; Lue, H.; Pope, C.N.; Cvetic, M.

    2005-10-14

    We construct the general solution for nonextremal charged rotating black holes in five-dimensional minimal gauged supergravity. They are characterized by four nontrivial parameters: namely, the mass, the charge, and the two independent rotation parameters. The metrics in general describe regular rotating black holes, providing the parameters lie in appropriate ranges so that naked singularities and closed timelike curves (CTCs) are avoided. We calculate the conserved energy, angular momenta, and charge for the solutions, and show how supersymmetric solutions arise in a Bogomol'nyi-Prasad-Sommerfield limit. These have naked CTCs in general, but for special choices of the parameters we obtain new regular supersymmetric black holes or smooth topological solitons.

  6. Investigation of Fuel Chemistry and Bed Performance in a Fluidized Bed Black Liquor Steam Reformer

    SciTech Connect (OSTI)

    Kevin Whitty

    2007-06-30

    University of Utah's project entitled 'Investigation of Fuel Chemistry and Bed Performance in a Fluidized Bed Black Liquor Steam Reformer' (DOE Cooperative Agreement DE-FC26-02NT41490) was developed in response to a solicitation released by the U.S. Department of Energy in December 2001, requesting proposals for projects targeted towards black liquor/biomass gasification technology support research and development. Specifically, the solicitation was seeking projects that would provide technical support for Department of Energy supported black liquor and biomass gasification demonstration projects under development at the time.

  7. Stringy stability of charged dilaton black holes with flat event horizon

    SciTech Connect (OSTI)

    Ong, Yen Chin; Chen, Pisin

    2015-01-15

    Electrically charged black holes with flat event horizon in anti-de Sitter space have received much attention due to various applications in Anti-de Sitter/Conformal Field Theory (AdS/CFT) correspondence, from modeling the behavior of quark-gluon plasma to superconductor. Critical to the physics on the dual field theory is the fact that when embedded in string theory, black holes in the bulk may become vulnerable to instability caused by brane pair-production. Since dilation arises naturally in the context of string theory, we study the effect of coupling dilation to Maxwell field on the stability of flat charged AdS black holes.

  8. Arctic Black Carbon Loading and Profile Using the Single-Particle...

    Office of Scientific and Technical Information (OSTI)

    Single-Particle Soot Photometer (SP2) Field Campaign Report Citation Details In-Document Search Title: Arctic Black Carbon Loading and Profile Using the Single-Particle Soot ...

  9. DOE/SC-ARM-14-017 Barrow Black Carbon Source and Impact Study

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    7 Barrow Black Carbon Source and Impact Study Final Campaign Report July 2014 DISCLAIMER This report was prepared as an account of work sponsored by the U.S. Government. Neither...

  10. Final/Technical Report on The National Conference of Black Physics Students

    SciTech Connect (OSTI)

    Williams, Elvira

    2001-06-01

    The 14th Annual Conference of the Society of Black Physics Students (NCBPS) was held March 16-19, 2000 at North Carolina A&T State University. The conference was held jointly with the National Society of Black Physicists. The students had the opportunity to interact and network with each other and the members of the profesional organization (NSBP). There are two attachments: Findings from the survey of participants of the 14th Annual National Conference of Black Physics Students, and XXVII Day of Scientific Lectures and 23rd Annual Meeting of The National Society of Black Physicists, March 15-18, 2000. The theme of the meeting was 'Physics: The science that shapes the future.'

  11. BINARY DISRUPTION BY MASSIVE BLACK HOLES: HYPERVELOCITY STARS, S STARS, AND TIDAL DISRUPTION EVENTS

    SciTech Connect (OSTI)

    Bromley, Benjamin C.; Kenyon, Scott J.; Geller, Margaret J.; Brown, Warren R. E-mail: skenyon@cfa.harvard.edu E-mail: wbrown@cfa.harvard.edu

    2012-04-20

    We examine whether disrupted binary stars can fuel black hole growth. In this mechanism, tidal disruption produces a single hypervelocity star (HVS) ejected at high velocity and a former companion star bound to the black hole. After a cluster of bound stars forms, orbital diffusion allows the black hole to accrete stars by tidal disruption at a rate comparable to the capture rate. In the Milky Way, HVSs and the S star cluster imply similar rates of 10{sup -5} to 10{sup -3} yr{sup -1} for binary disruption. These rates are consistent with estimates for the tidal disruption rate in nearby galaxies and imply significant black hole growth from disrupted binaries on 10 Gyr timescales.

  12. Thermodynamics of black holes in (n+1)-dimensional Einstein-Born-Infeld-dilaton gravity

    SciTech Connect (OSTI)

    Sheykhi, A.; Riazi, N.

    2007-01-15

    We construct a new class of (n+1)-dimensional (n{>=}3) black hole solutions in Einstein-Born-Infeld-dilaton gravity with Liouville-type potential for the dilaton field and investigate their properties. These solutions are neither asymptotically flat nor (anti)-de Sitter. We find that these solutions can represent black holes, with inner and outer event horizons, an extreme black hole, or a naked singularity provided the parameters of the solutions are chosen suitably. We compute the thermodynamic quantities of the black hole solutions and find that these quantities satisfy the first law of thermodynamics. We also perform a stability analysis and investigate the effect of dilaton on the stability of the solutions.

  13. Hidden symmetries, null geodesics, and photon capture in the Sen black hole

    SciTech Connect (OSTI)

    Hioki, Kenta; Miyamoto, Umpei

    2008-08-15

    Important classes of null geodesics and hidden symmetries in the Sen black hole are investigated. First, we obtain the principal null geodesics and circular photon orbits. Then, an irreducible rank-two Killing tensor and a conformal Killing tensor are derived, which represent the hidden symmetries. Analyzing the properties of Killing tensors, we clarify why the Hamilton-Jacobi and wave equations are separable in this spacetime. We also investigate the gravitational capture of photons by the Sen black hole and compare the result with those by the various charged/rotating black holes and naked singularities in the Kerr-Newman family. For these black holes and naked singularities, we show the capture regions in a two dimensional impact parameter space (or equivalently the 'shadows' observed at infinity) to form a variety of shapes such as the disk, circle, dot, arc, and their combinations.

  14. Thermodynamics of asymptotically flat charged black holes in third order Lovelock gravity

    SciTech Connect (OSTI)

    Dehghani, M.H.; Shamirzaie, M.

    2005-12-15

    We present a new class of asymptotically flat charge static solutions in third order Lovelock gravity. These solutions present black hole solutions with two inner and outer event horizons, extreme black holes, or naked singularities provided the parameters of the solutions are chosen suitable. We find that the uncharged asymptotically flat solutions can present black holes with two inner and outer horizons. This kind of solution does not exist in Einstein or Gauss-Bonnet gravity, and it is a special effect in third order Lovelock gravity. We compute temperature, entropy, charge, electric potential, and mass of the black hole solutions, and find that these quantities satisfy the first law of thermodynamics. We also perform a stability analysis by computing the determinant of the Hessian matrix of the mass with respect to its thermodynamic variables in both the canonical and the grand-canonical ensembles, and show that there exists only an intermediate stable phase.

  15. Causal extraction of black hole rotational energy by various kinds of electromagnetic fields

    SciTech Connect (OSTI)

    Koide, Shinji; Baba, Tamon

    2014-09-10

    Recent general relativistic magnetohydrodynamics (MHD) simulations have suggested that relativistic jets from active galactic nuclei (AGNs) have been powered by the rotational energy of central black holes. Some mechanisms for extraction of black hole rotational energy have been proposed, like the Penrose process, Blandford-Znajek mechanism, MHD Penrose process, and superradiance. The Blandford-Znajek mechanism is the most promising mechanism for the engines of the relativistic jets from AGNs. However, an intuitive interpretation of this mechanism with causality is not yet clarified, while the Penrose process has a clear interpretation for causal energy extraction from a black hole with negative energy. In this paper, we present a formula to build physical intuition so that in the Blandford-Znajek mechanism, as well as in other electromagnetic processes, negative electromagnetic energy plays an important role in causal extraction of the rotational energy of black holes.

  16. Thin-layer black phosphorous/GaAs heterojunction p-n diodes

    SciTech Connect (OSTI)

    Gehring, Pascal; Urcuyo, Roberto; Duong, Dinh Loc; Burghard, Marko; Kern, Klaus

    2015-06-08

    Owing to its high carrier mobility and thickness-tunable direct band gap, black phosphorous emerges as a promising component of optoelectronic devices. Here, we evaluate the device characteristics of p-n heterojunction diodes wherein thin black phosphorous layers are interfaced with an underlying, highly n-doped GaAs substrate. The p-n heterojunctions exhibit close-to-ideal diode behavior at low bias, while under illumination they display a photoresponse that is evenly distributed over the entire junction area, with an external quantum efficiency of up to 10% at zero bias. Moreover, the observed maximum open circuit voltage of 0.6 V is consistent with the band gap estimated for a black phosphorous sheet with a thickness on the order of 10?nm. Further analysis reveals that the device performance is limited by the structural quality of the black phosphorous surface.

  17. Higgs production and decay from TeV scale black holes at the...

    Office of Scientific and Technical Information (OSTI)

    We compare our results with the standard model backgrounds. We find that Higgs production from black holes is dominant over standard model production for psub Tsup H>100 GeV, ...

  18. Savannah River National Laboratory Meets with Historically Black Colleges and Universities

    Broader source: Energy.gov [DOE]

    Student and faculty leaders at Historically Black Colleges and Universities (HBCUs) spent the day at the Center for Hydrogen Research at Savannah River National Laboratory, reporting on their work to professional scientists and engineers at the Laboratory.

  19. Superradiance and black hole bomb in five-dimensional minimal ungauged supergravity

    SciTech Connect (OSTI)

    Aliev, Alikram N.

    2014-11-01

    We examine the black hole bomb model which consists of a rotating black hole of five-dimenensional minimal ungauged supergravity and a reflecting mirror around it. For low-frequency scalar perturbations, we find solutions to the Klein-Gordon equation in the near-horizon and far regions of the black hole spacetime. To avoid solutions with logarithmic terms, we assume that the orbital quantum number l takes on nearly, but not exactly, integer values and perform the matching of these solutions in an intermediate region. This allows us to calculate analytically the frequency spectrum of quasinormal modes, taking the limits as l approaches even or odd integers separately. We find that all l modes of scalar perturbations undergo negative damping in the regime of superradiance, resulting in exponential growth of their amplitudes. Thus, the model under consideration would exhibit the superradiant instability, eventually behaving as a black hole bomb in five dimensions.

  20. Black History Month: Former Energy Secretary Broke Barriers and Advanced Clean Energy

    Broader source: Energy.gov [DOE]

    Black History Month celebrates the many vital contributions African Americans have made in America’s history.  Today, we’re highlighting African Americans who have helped advance energy efficiency...

  1. Quasinormal modes, scattering, and Hawking radiation of Kerr-Newman black holes in a magnetic field

    SciTech Connect (OSTI)

    Kokkotas, K. D.; Konoplya, R. A.; Zhidenko, A.

    2011-01-15

    We perform a comprehensive analysis of the spectrum of proper oscillations (quasinormal modes), transmission/reflection coefficients, and Hawking radiation for a massive charged scalar field in the background of the Kerr-Newman black hole immersed in an asymptotically homogeneous magnetic field. There are two main effects: the Zeeman shift of the particle energy in the magnetic field and the difference of values of an electromagnetic potential between the horizon and infinity, i.e. the Faraday induction. We have shown that 'turning on' the magnetic field induces a stronger energy-emission rate and leads to 'recharging' of the black hole. Thus, a black hole immersed in a magnetic field evaporates much quicker, achieving thereby an extremal state in a shorter period of time. Quasinormal modes are moderately affected by the presence of a magnetic field which is assumed to be relatively small compared to the gravitational field of the black hole.

  2. SUPER-CRITICAL GROWTH OF MASSIVE BLACK HOLES FROM STELLAR-MASS SEEDS

    SciTech Connect (OSTI)

    Madau, Piero; Haardt, Francesco; Dotti, Massimo

    2014-04-01

    We consider super-critical accretion with angular momentum onto stellar-mass black holes as a possible mechanism for growing billion-solar-mass black holes from light seeds at early times. We use the radiatively inefficient ''slim disk'' solutionadvective, optically thick flows that generalize the standard geometrically thin disk modelto show how mildly super-Eddington intermittent accretion may significantly ease the problem of assembling the first massive black holes when the universe was less than 0.8Gyr old. Because of the low radiative efficiencies of slim disks around non-rotating as well as rapidly rotating black holes, the mass e-folding timescale in this regime is nearly independent of the spin parameter. The conditions that may lead to super-critical growth in the early universe are briefly discussed.

  3. AmeriFlux CA-Man Manitoba - Northern Old Black Spruce (former BOREAS Northern Study Area)

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Amiro, Brian [University of Manitoba

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site CA-Man Manitoba - Northern Old Black Spruce (former BOREAS Northern Study Area). Site Description - 55.880° N, 98.481° W, elevation of 259 m, Boreal coniferous: Black spruce; occasional larch present in poorly-drained areas. Groundcover is moss (feathermosses and Sphagnum), Labrador Tea, Vaccinium, and willows are a main component of the understory. It was established in 1993 as a BOREAS site.

  4. Wet-chemical systems and methods for producing black silicon substrates

    DOE Patents [OSTI]

    Yost, Vernon; Yuan, Hao-Chih; Page, Matthew

    2015-05-19

    A wet-chemical method of producing a black silicon substrate. The method comprising soaking single crystalline silicon wafers in a predetermined volume of a diluted inorganic compound solution. The substrate is combined with an etchant solution that forms a uniform noble metal nanoparticle induced Black Etch of the silicon wafer, resulting in a nanoparticle that is kinetically stabilized. The method comprising combining with an etchant solution having equal volumes acetonitrile/acetic acid:hydrofluoric acid:hydrogen peroxide.

  5. Analysis of the Sultana-Dyer cosmological black hole solution of the Einstein equations

    SciTech Connect (OSTI)

    Faraoni, Valerio

    2009-08-15

    The Sultana-Dyer solution of general relativity representing a black hole embedded in a special cosmological background is analyzed. We find an expanding (weak) spacetime singularity instead of the reported conformal Killing horizon, which is covered by an expanding black hole apparent horizon (internal to a cosmological apparent horizon) for most of the history of the Universe. This singularity was naked early on. The global structure of the solution is studied as well.

  6. Energy Department Announces New Technical Review to Assess Black Cells at

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Hanford's Waste Treatment Plant | Department of Energy Technical Review to Assess Black Cells at Hanford's Waste Treatment Plant Energy Department Announces New Technical Review to Assess Black Cells at Hanford's Waste Treatment Plant August 2, 2012 - 12:15pm Addthis News Media Contact (202) 586-4940 WASHINGTON -- The U.S. Department of Energy announced today that Secretary of Energy Steven Chu has assembled a group of independent technical experts to assess the Hanford Site's Waste

  7. HOW IMPORTANT IS THE DARK MATTER HALO FOR BLACK HOLE GROWTH?

    SciTech Connect (OSTI)

    Volonteri, Marta; Gueltekin, Kayhan; Natarajan, Priyamvada

    2011-08-20

    In this paper, we examine whether the properties of central black holes in galactic nuclei correlate with their host dark matter halos. We analyze the entire sample of galaxies where black hole mass, velocity dispersion {sigma}, and asymptotic circular velocity V{sub c} have all been measured. We fit M{sub BH}-{sigma} and M{sub BH}-V{sub c} to a power law, and find that in both relationships the scatter and slope are similar. This model-independent analysis suggests that although the black hole masses are not uniquely determined by dark matter halo mass, when considered for the current sample as a whole, the M{sub BH}-V{sub c} correlation may be as strong (or as weak) as M{sub BH}-{sigma}. Although the data are sparse, there appears to be more scatter in the correlation for both {sigma} and V{sub c} at the low-mass end. This is not unexpected given our current understanding of galaxy and black hole assembly. In fact, there are several compelling reasons that account for this: (1) supermassive black hole (SMBH) formation is likely less efficient in low-mass galaxies with large angular momentum content, (2) SMBH growth is less efficient in low-mass disk galaxies that have not experienced major mergers, and (3) dynamical effects, such as gravitational recoil, increase scatter preferentially at the low-mass end. Therefore, the recent observational claim of the absence of central SMBHs in bulgeless, low-mass galaxies, or deviations from the correlations defined by high-mass black holes in large galaxies today is, in fact, predicated by current models of black hole growth. We show how this arises as a direct consequence of the coupling between dark matter halos and central black holes at the earliest epochs.

  8. Gravitational Waves from Coalescing Binary Black Holes: Theoretical and Experimental Challenges

    ScienceCinema (OSTI)

    None

    2011-10-06

    A network of ground-based interferometric gravitational wave detectors (LIGO/VIRGO/GEO/...) is currently taking data near its planned sensitivity. Coalescing black hole binaries are among the most promising, and most exciting, gravitational wave sources for these detectors. The talk will review the theoretical and experimental challenges that must be met in order to successfully detect gravitational waves from coalescing black hole binaries, and to be able to reliably measure the physical parameters of the source (masses, spins, ...).

  9. Red & Black Ball raises nearly $82,000 for youth

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Red & Black Ball raises $81,000 for youth Community Connections: Your link to news and opportunities from Los Alamos National Laboratory Latest Issue: September 1, 2016 all issues All Issues » submit Red & Black Ball raises nearly $82,000 for youth The Family YMCA receives windfall for Española and Los Alamos teen centers. April 4, 2016 From left: LANL Government Affairs Office Director Patrick Woehrle, LANL Community Programs Office Director Kathy Keith, Laboratory Director Charles

  10. COLLOQUIUM: The Observation of Gravitational Waves from a Binary Black Hole

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Merger | Princeton Plasma Physics Lab 29, 2016, 4:15pm to 5:30pm Colloquia MBG Auditorium, PPPL (284 cap.) COLLOQUIUM: The Observation of Gravitational Waves from a Binary Black Hole Merger Dr. Duncan Brown Syracuse University On September 14, 2015 the the two detectors of the Laser Interferometer Gravitational-Wave Observatory (LIGO) simultaneously observed gravitational waves from a binary black hole merger. The gravitational waves observed match the waveform predicted by general

  11. T-602: BlackBerry Enterprise Server Input Validation Flaw in BlackBerry Web Desktop Manager Permits Cross-Site Scripting Attacks

    Broader source: Energy.gov [DOE]

    The BlackBerry Web Desktop Manager not properly filter HTML code from user-supplied input before displaying the input. A remote user can cause arbitrary scripting code to be executed by the target user's browser. The code will originate from the site running the BlackBerry Web Desktop Manager software and will run in the security context of that site. As a result, the code will be able to access the target user's cookies (including authentication cookies), if any, associated with the site, access data recently submitted by the target user via web form to the site, or take actions on the site acting as the target user.

  12. Very large radiative transfer over small distances from a black body for thermophotovoltaic applications

    SciTech Connect (OSTI)

    Pan, J.L.; Choy, H.K.H.; Fonstad, C.G. Jr.

    2000-01-01

    The maximum amount of radiated heat intensity which can be transferred from a black body of refractive index n{sub BB} to an object of refractive index n{sub OBJ} located a short distance away is shown to be n{sup 2}{sub smaller} times the free space Planck distribution, where n{sub smaller} is the smaller of n{sub BB} and n{sub OBJ}, and where n{sub BB} and n{sub OBJ} are assumed greater than unity. The implication is that the radiative power spectral density within a thermophotovoltaic cell could be designed to be much greater than the free space Planck distribution. The maximum radiative intensity transferred occurs when the index of the black body matches that of the object at wavelengths where the Planck distribution is sizeable. A simple expression is found for the transferred radiative intensity as a function of the refractive indices of, and the distance separating, the black body and the object. The expression is interpreted in terms of the specific black body modes which are evanescent in the space between the black body and the object and which make the largest contribution to the transmission of radiation. The black body, the object, and the gap region are all modeled as lossless dielectrics.

  13. Observing the shadow of Einstein-Maxwell-Dilaton-Axion black hole

    SciTech Connect (OSTI)

    Wei, Shao-Wen; Liu, Yu-Xiao E-mail: liuyx@lzu.edu.cn

    2013-11-01

    In this paper, the shadows cast by Einstein-Maxwell-Dilaton-Axion black hole and naked singularity are studied. The shadow of a rotating black hole is found to be a dark zone covered by a deformed circle. For a fixed value of the spin a, the size of the shadow decreases with the dilaton parameter b. The distortion of the shadow monotonically increases with b and takes its maximal when the black hole approaches to the extremal case. Due to the optical properties, the area of the black hole shadow is supposed to equal to the high-energy absorption cross section. Based on this assumption, the energy emission rate is investigated. For a naked singularity, the shadow has a dark arc and a dark spot or straight, and the corresponding observables are obtained. These results show that there is a significant effect of the spin a and dilaton parameter b on these shadows. Moreover, we examine the observables of the shadow cast by the supermassive black hole at the center of the Milky Way, which is very useful for us to probe the nature of the black hole through the astronomical observations in the near future.

  14. BPS-like bound and thermodynamics of the charged BTZ black hole

    SciTech Connect (OSTI)

    Cadoni, Mariano; Monni, Cristina

    2009-07-15

    The charged Banados-Teitelboim-Zanelli (BTZ) black hole is plagued by several pathologies: (a) Divergent boundary terms are present in the action; hence, we have a divergent black-hole mass. (b) Once a finite, renormalized, mass M is defined, black-hole states exist for arbitrarily negative values of M. (c) There is no upper bound on the charge Q. We show that these pathological features are an artifact of the renormalization procedure. They can be completely removed by using an alternative renormalization scheme leading to a different definition M{sub 0} of the black-hole mass, which is the total energy inside the horizon. The new mass satisfies a BPS-like bound M{sub 0}{>=}({pi}/2)Q{sup 2}, and the heat capacity of the hole is positive. We also discuss the black-hole thermodynamics that arises when M{sub 0} is interpreted as the internal energy of the system. We show, using three independent approaches (black-hole thermodynamics, Einstein equations, and Euclidean action formulation), that M{sub 0} satisfies the first law if a term describing the mechanical work done by the electrostatic pressure is introduced.

  15. Linking the spin evolution of massive black holes to galaxy kinematics

    SciTech Connect (OSTI)

    Sesana, A.; Barausse, E.; Dotti, M.; Rossi, E. M. E-mail: barausse@iap.fr E-mail: emr@strw.leidenuniv.nl

    2014-10-20

    We present the results of a semianalytical model that evolves the masses and spins of massive black holes together with the properties of their host galaxies across the cosmic history. As a consistency check, our model broadly reproduces a number of observations, e.g., the cosmic star formation history; the black hole mass, luminosity, and galaxy mass functions at low redshift; the black hole-bulge mass relation; and the morphological distribution at low redshift. For the first time in a semianalytical investigation, we relax the simplifying assumptions of perfect coherency or perfect isotropy of the gas fueling the black holes. The dynamics of gas is instead linked to the morphological properties of the host galaxies, resulting in different spin distributions for black holes hosted in different galaxy types. We compare our results with the observed sample of spin measurements obtained through broad K? iron line fitting. The observational data disfavor both accretion along a fixed direction and isotropic fueling. Conversely, when the properties of the accretion flow are anchored to the kinematics of the host galaxy, we obtain a good match between theoretical expectations and observations. A mixture of coherent accretion and phases of activity in which the gas dynamics is similar to that of the stars in bulges (i.e., with a significant velocity dispersion superimposed to a net rotation) best describes the data, adding further evidence in support of the coevolution of massive black holes and their hosts.

  16. WHAT'S INSIDE THE BLACK BOX - EXPLAINING PERFORMANCE ASSESSMENT TO STAKEHOLDERS

    SciTech Connect (OSTI)

    Seitz, R; Elmer Wilhite, E

    2009-01-06

    The performance assessment (PA) process is being applied to support an increasing variety of waste management decisions that involve the whole spectrum of stakeholders. As with many technical tools, the PA process can be seen as a black box, which can be difficult to understand when implemented. Recognizing the increasing use of PA and the concerns about difficulties with understanding, the Savannah River Site Citizens Advisory Board (CAB) made a recommendation that the U.S. Department of Energy (DOE) provide a Public Educational Forum on PAs. The DOE-Headquarters Environmental Management (DOE-EM) Office of Compliance and the DOE-Savannah River (DOE-SR) responded to this recommendation by supporting the Savannah River National Laboratory (SRNL) in developing several presentation modules that can be used to describe different aspects of the PA process. For the Public Educational Forum, the PA modules were combined with presentations on DOE perspectives, historical modeling efforts at the Savannah River Site, and review perspectives from the U.S. Nuclear Regulatory Commission (NRC). The overall goals are to help the public understand how PAs are implemented and the rigor that is applied, and to provide insight into the use of PAs for waste management decision-making.

  17. First principles study of metal contacts to monolayer black phosphorous

    SciTech Connect (OSTI)

    Chanana, Anuja; Mahapatra, Santanu

    2014-11-28

    Atomically thin layered black phosphorous (BP) has recently appeared as an alternative to the transitional metal dichalcogenides for future channel material in a metal-oxide-semiconductor transistor due to its lower carrier effective mass. Investigation of the electronic property of source/drain contact involving metal and two-dimensional material is essential as it impacts the transistor performance. In this paper, we perform a systematic and rigorous study to evaluate the Ohmic nature of the side-contact formed by the monolayer BP (mBP) and metals (gold, titanium, and palladium), which are commonly used in experiments. Employing the Density Functional Theory, we analyse the potential barrier, charge transfer and atomic orbital overlap at the metal-mBP interface in an optimized structure to understand how efficiently carriers could be injected from metal contact to the mBP channel. Our analysis shows that gold forms a Schottky contact with a higher tunnel barrier at the interface in comparison to the titanium and palladium. mBP contact with palladium is found to be purely Ohmic, where as titanium contact demonstrates an intermediate behaviour.

  18. Black carbon aerosols and the third polar ice cap

    SciTech Connect (OSTI)

    Menon, Surabi; Koch, Dorothy; Beig, Gufran; Sahu, Saroj; Fasullo, John; Orlikowski, Daniel

    2010-04-15

    Recent thinning of glaciers over the Himalayas (sometimes referred to as the third polar region) have raised concern on future water supplies since these glaciers supply water to large river systems that support millions of people inhabiting the surrounding areas. Black carbon (BC) aerosols, released from incomplete combustion, have been increasingly implicated as causing large changes in the hydrology and radiative forcing over Asia and its deposition on snow is thought to increase snow melt. In India BC emissions from biofuel combustion is highly prevalent and compared to other regions, BC aerosol amounts are high. Here, we quantify the impact of BC aerosols on snow cover and precipitation from 1990 to 2010 over the Indian subcontinental region using two different BC emission inventories. New estimates indicate that Indian BC emissions from coal and biofuel are large and transport is expected to expand rapidly in coming years. We show that over the Himalayas, from 1990 to 2000, simulated snow/ice cover decreases by {approx}0.9% due to aerosols. The contribution of the enhanced Indian BC to this decline is {approx}36%, similar to that simulated for 2000 to 2010. Spatial patterns of modeled changes in snow cover and precipitation are similar to observations (from 1990 to 2000), and are mainly obtained with the newer BC estimates.

  19. The mass of the black hole in LMC X-3

    SciTech Connect (OSTI)

    Orosz, Jerome A.; Steiner, James F.; McClintock, Jeffrey E.; Buxton, Michelle M.; Bailyn, Charles D.; Steeghs, Danny; Guberman, Alec; Torres, Manuel A. P. E-mail: jsteiner@cfa.harvard.edu E-mail: michelle.buxton@yale.edu E-mail: D.T.H.Steeghs@warwick.ac.uk E-mail: M.Torres@sron.nl

    2014-10-20

    We analyze a large set of new and archival photometric and spectroscopic observations of LMC X-3 to arrive at a self-consistent dynamical model for the system. Using echelle spectra obtained with the Magellan Inamori Kyocera Echelle instrument on the 6.5 m Magellan Clay telescope and the UVES instrument on the second 8.2 m Very Large Telescope, we find a velocity semiamplitude for the secondary star of K {sub 2} = 241.1 6.2 km s{sup 1}, where the uncertainty includes an estimate of the systematic error caused by X-ray heating. Using the spectra, we also find a projected rotational velocity of V {sub rot}sin i = 118.5 6.6 km s{sup 1}. From an analysis of archival B and V light curves as well as new B and V light curves from the SMARTS 1.3 m telescope, we find an inclination of i = 69.84 0.37 for models that do not include X-ray heating and an inclination of i = 69.24 0.72 for models that incorporate X-ray heating. Adopting the latter inclination measurement, we find masses of 3.63 0.57 M {sub ?} and 6.98 0.56 M {sub ?} for the companion star and the black hole, respectively. We briefly compare our results with earlier work and discuss some of their implications.

  20. BLINDLY DETECTING MERGING SUPERMASSIVE BLACK HOLES WITH RADIO SURVEYS

    SciTech Connect (OSTI)

    Kaplan, D. L.; O'Shaughnessy, R.; Sesana, A.; Volonteri, M. E-mail: oshaughn@gravity.phys.uwm.edu E-mail: martav@umich.edu

    2011-06-20

    Supermassive black holes (SMBHs) presumably grow through numerous mergers throughout cosmic time. During each merger, SMBH binaries are surrounded by a circumbinary accretion disk that imposes a significant ({approx}10{sup 4} G for a binary of 10{sup 8} M{sub sun}) magnetic field. The motion of the binary through that field will convert the field energy to Poynting flux, with a luminosity {approx}10{sup 43} erg s{sup -1} (B/10{sup 4} G){sup 2}(M/10{sup 8} M{sub sun}){sup 2}, some of which may emerge as synchrotron emission at frequencies near 1 GHz where current and planned wide-field radio surveys will operate. We find that the short timescales of many mergers will limit their detectability with most planned blind surveys to <1 per year over the whole sky, independent of the details of the emission process and flux distribution. Including an optimistic estimate for the radio flux makes detection even less likely, with <0.1 mergers per year over the whole sky. However, wide-field radio instruments may be able to localize systems identified in advance of merger by gravitational waves. Further, radio surveys may be able to detect the weaker emission produced by the binary's motion as it is modulated by spin-orbit precession and inspiral well in advance of merger.

  1. Black Carbon Radiative Forcing over the Tibetan Plateau

    SciTech Connect (OSTI)

    He, Cenlin; Li, Qinbin; Liou, K. N.; Takano, Y.; Gu, Yu; Qi, L.; Mao, Yuhao; Leung, Lai-Yung R.

    2014-11-28

    We estimate the snow albedo forcing and direct radiative forcing (DRF) of black carbon (BC) in the Tibetan Plateau using a global chemical transport model in conjunction with a stochastic snow model and a radiative transfer model. Our best estimate of the annual BC snow albedo forcing in the Plateau is 2.9 W m-2 (uncertainty: 1.55.0 W m-226 ). We find that BC-snow internal mixing increases the albedo forcing by 40-60% compared with external mixing and coated BC increases the forcing by 30-50% compared with uncoated BC, whereas Koch snowflakes reduce the forcing by 20-40% relative to spherical snow grains. Our best estimate of the annual BC DRF at the top of the atmosphere is 2.3 W m-2 (uncertainty: 0.74.3 W m-230 ) in the Plateau after scaling the modeled BC absorption optical depth to Aerosol Robotic Network (AERONET) observations. The BC forcings are attributed to emissions from different regions.

  2. Soro West: A non-seismically defined, fault cut-off prospect in the Papuan Fold and Thrust Belt, Papua New Guinea

    SciTech Connect (OSTI)

    Robinson, W.F. ); Swift, C.M. Jr. )

    1996-01-01

    Soro West is a fault cut-off prospect located in the frontal portion of the Papuan Fold and Thrust Belt. Prospective Toro and Imburu sandstones are interpreted to be in the hanging wall of the Soro Thrust. Truncation against the thrust, both updip and through lateral ramps, provides the trapping mechanism. The Soro West Prospect was defined using geological, geochemical, remote sensing, and geophysical data. The definition and location of the trap is a primary risk and work was focused on this aspect. Surface geological data (lithology, strikes, and dips) topography and synthetic aperture radar imagery were incorporated into the evaluation. Statistical curvature analysis techniques helped define the shape of the structure and the locations of the lateral ramps. Strontium isotope analyses of Darai Limestone surface samples refined erosional levels using a locally-derived reference curve. Severe karst precludes the acquisition of coherent surface seismic data, so the primary geophysical tool used was magnetotellurics (MT). A detailed, pre-survey feasibility study defined expected responses from alternative structural models. The MT data demonstrated that the limestone at surface is underlain by thick conductive clastics and not another Darai Limestone sheet. The data also constrained the range of fault cut-off positions significantly. Multiple, three-dimensionally consistent, restorable alternative structural models were created using results from all analyses. These led to a positive assessment of the prospect and an exploratory test is to be drilled in 1996.

  3. Soro West: A non-seismically defined, fault cut-off prospect in the Papuan Fold and Thrust Belt, Papua New Guinea

    SciTech Connect (OSTI)

    Robinson, W.F.; Swift, C.M. Jr.

    1996-12-31

    Soro West is a fault cut-off prospect located in the frontal portion of the Papuan Fold and Thrust Belt. Prospective Toro and Imburu sandstones are interpreted to be in the hanging wall of the Soro Thrust. Truncation against the thrust, both updip and through lateral ramps, provides the trapping mechanism. The Soro West Prospect was defined using geological, geochemical, remote sensing, and geophysical data. The definition and location of the trap is a primary risk and work was focused on this aspect. Surface geological data (lithology, strikes, and dips) topography and synthetic aperture radar imagery were incorporated into the evaluation. Statistical curvature analysis techniques helped define the shape of the structure and the locations of the lateral ramps. Strontium isotope analyses of Darai Limestone surface samples refined erosional levels using a locally-derived reference curve. Severe karst precludes the acquisition of coherent surface seismic data, so the primary geophysical tool used was magnetotellurics (MT). A detailed, pre-survey feasibility study defined expected responses from alternative structural models. The MT data demonstrated that the limestone at surface is underlain by thick conductive clastics and not another Darai Limestone sheet. The data also constrained the range of fault cut-off positions significantly. Multiple, three-dimensionally consistent, restorable alternative structural models were created using results from all analyses. These led to a positive assessment of the prospect and an exploratory test is to be drilled in 1996.

  4. Spectrum of relativistic radiation from electric charges and dipoles as they fall freely into a black hole

    SciTech Connect (OSTI)

    Shatskiy, A. A. Novikov, I. D.; Lipatova, L. N.

    2013-06-15

    The motion of electric charges and dipoles falling radially and freely into a Schwarzschild black hole is considered. The inverse effect of the electromagnetic fields on the black hole is neglected. Since the dipole is assumed to be a point particle, the deformation due to the action of tidal forces on it is neglected. According to the theorem stating that 'black holes have no hair', the multipole electromagnetic fields should be completely radiated as a multipole falls into a black hole. The electromagnetic radiation power spectrum for these multipoles (a monopole and a dipole) has been found. Differences have been found in the spectra for different orientations of the falling dipole. A general method has been developed to find the radiated multipole electromagnetic fields for multipoles (including higher-order multipoles-quadrupoles, etc.) falling freely into a black hole. The calculated electromagnetic spectra can be compared with observational data from stellar-mass and smaller black holes.

  5. Selection and Characterization of Carbon Black and Surfactants for Development of Small Scale Uranium Oxicarbide Kernels

    SciTech Connect (OSTI)

    Contescu, Cristian I

    2006-01-01

    This report supports the effort for development of small scale fabrication of UCO (a mixture of UO{sub 2} and UC{sub 2}) fuel kernels for the generation IV high temperature gas reactor program. In particular, it is focused on optimization of dispersion conditions of carbon black in the broths from which carbon-containing (UO{sub 2} {center_dot} H{sub 2}O + C) gel spheres are prepared by internal gelation. The broth results from mixing a hexamethylenetetramine (HMTA) and urea solution with an acid-deficient uranyl nitrate (ADUN) solution. Carbon black, which is previously added to one or other of the components, must stay dispersed during gelation. The report provides a detailed description of characterization efforts and results, aimed at identification and testing carbon black and surfactant combinations that would produce stable dispersions, with carbon particle sizes below 1 {micro}m, in aqueous HMTA/urea and ADUN solutions. A battery of characterization methods was used to identify the properties affecting the water dispersability of carbon blacks, such as surface area, aggregate morphology, volatile content, and, most importantly, surface chemistry. The report introduces the basic principles for each physical or chemical method of carbon black characterization, lists the results obtained, and underlines cross-correlations between methods. Particular attention is given to a newly developed method for characterization of surface chemical groups on carbons in terms of their acid-base properties (pK{sub a} spectra) based on potentiometric titration. Fourier-transform infrared (FTIR) spectroscopy was used to confirm the identity of surfactants, both ionic and non-ionic. In addition, background information on carbon black properties and the mechanism by which surfactants disperse carbon black in water is also provided. A list of main physical and chemical properties characterized, samples analyzed, and results obtained, as well as information on the desired trend or

  6. Linearity of Climate Response to Increases in Black Carbon Aerosols

    SciTech Connect (OSTI)

    Mahajan, Salil; Evans, Katherine J.; Hack, James J.; Truesdale, John

    2013-04-19

    The impact of absorbing aerosols on global climate are not completely understood. Here, we present results of idealized experiments conducted with the Community Atmosphere Model (CAM4) coupled to a slab ocean model (CAM4-SOM) to simulate the climate response to increases in tropospheric black carbon aerosols (BC) by direct and semi-direct effects. CAM4-SOM was forced with 0, 1x, 2x, 5x and 10x an estimate of the present day concentration of BC while maintaining their estimated present day global spatial and vertical distribution. The top of the atmosphere (TOA) radiative forcing of BC in these experiments is positive (warming) and increases linearly as the BC burden increases. The total semi-direct effect for the 1x experiment is positive but becomes increasingly negative for higher BC concentrations. The global average surface temperature response is found to be a linear function of the TOA radiative forcing. The climate sensitivity to BC from these experiments is estimated to be 0.42 K $ W^{-1} m^{2}$ when the semi-direct effects are accounted for and 0.22 K $ W^{-1} m^{2}$ with only the direct effects considered. Global average precipitation decreases linearly as BC increases, with a precipitation sensitivity to atmospheric absorption of 0.4 $\\%$ $W^{-1}m^{2}$ . The hemispheric asymmetry of BC also causes an increase in southward cross-equatorial heat transport and a resulting northward shift of the inter-tropical convergence zone in the simulations at a rate of 4$^{\\circ}$N $ PW^{-1}$. Global average mid- and high-level clouds decrease, whereas the low-level clouds increase linearly with BC. The increase in marine stratocumulus cloud fraction over the south tropical Atlantic is caused by increased BC-induced diabatic heating of the free troposphere.

  7. U-012: BlackBerry Enterprise Server Collaboration Service Bug Lets Remote Users Impersonate Intra-organization Messages

    Office of Energy Efficiency and Renewable Energy (EERE)

    A vulnerability was reported in BlackBerry Enterprise Server. A remote user can impersonate another messaging user within the same organization.

  8. THE ANGULAR MOMENTA OF NEUTRON STARS AND BLACK HOLES AS A WINDOW ON SUPERNOVAE

    SciTech Connect (OSTI)

    Miller, J. M.; Miller, M. C.; Reynolds, C. S.

    2011-04-10

    It is now clear that a subset of supernovae displays evidence for jets and is observed as gamma-ray bursts (GRBs). The angular momentum distribution of massive stellar endpoints provides a rare means of constraining the nature of the central engine in core-collapse explosions. Unlike supermassive black holes, the spin of stellar-mass black holes in X-ray binary systems is little affected by accretion and accurately reflects the spin set at birth. A modest number of stellar-mass black hole angular momenta have now been measured using two independent X-ray spectroscopic techniques. In contrast, rotation-powered pulsars spin down over time, via magnetic braking, but a modest number of natal spin periods have now been estimated. For both canonical and extreme neutron star parameters, statistical tests strongly suggest that the angular momentum distributions of black holes and neutron stars are markedly different. Within the context of prevalent models for core-collapse supernovae, the angular momentum distributions are consistent with black holes typically being produced in GRB-like supernovae with jets and with neutron stars typically being produced in supernovae with too little angular momentum to produce jets via magnetohydrodynamic processes. It is possible that neutron stars are with high spin initially and rapidly spun down shortly after the supernova event, but the available mechanisms may be inconsistent with some observed pulsar properties.

  9. Transition from adiabatic inspiral to plunge into a spinning black hole

    SciTech Connect (OSTI)

    Kesden, Michael

    2011-05-15

    A test particle of mass {mu} on a bound geodesic of a Kerr black hole of mass M>>{mu} will slowly inspiral as gravitational radiation extracts energy and angular momentum from its orbit. This inspiral can be considered adiabatic when the orbital period is much shorter than the time scale on which energy is radiated, and quasicircular when the radial velocity is much less than the azimuthal velocity. Although the inspiral always remains adiabatic provided {mu}<black hole's spin changes following a test-particle merger, and can be extrapolated to help predict the mass and spin of the final black hole produced in finite-mass-ratio black-hole mergers. Our new contribution is particularly important for nearly maximally spinning black holes, as it can affect whether a merger produces a naked singularity.

  10. ELECTRON IRRADIATION OF KUIPER BELT SURFACE ICES: TERNARY N{sub 2}-CH{sub 4}-CO MIXTURES AS A CASE STUDY

    SciTech Connect (OSTI)

    Kim, Y. S.; Kaiser, R. I.

    2012-10-10

    The space weathering of icy Kuiper Belt Objects was investigated in this case study by exposing methane (CH{sub 4}) and carbon monoxide (CO) doped nitrogen (N{sub 2}) ices at 10 K to ionizing radiation in the form of energetic electrons. Online and in situ Fourier transform infrared spectroscopy was utilized to monitor the radiation-induced chemical processing of these ices. Along with isocyanic acid (HNCO), the products could be mainly derived from those formed in irradiated binary ices of the N{sub 2}-CH{sub 4} and CO-CH{sub 4} systems: nitrogen-bearing products were found in the form of hydrogen cyanide (HCN), hydrogen isocyanide (HNC), diazomethane (CH{sub 2}N{sub 2}), and its radical fragment (HCN{sub 2}); oxygen-bearing products were of acetaldehyde (CH{sub 3}CHO), formyl radical (HCO), and formaldehyde (H{sub 2}CO). As in the pure ices, the methyl radical (CH{sub 3}) and ethane (C{sub 2}H{sub 6}) were also detected, as were carbon dioxide (CO{sub 2}) and the azide radical (N{sub 3}). Based on the temporal evolution of the newly formed products, kinetic reaction schemes were then developed to fit the temporal profiles of the newly formed species, resulting in numerical sets of rate constants. The current study highlights important constraints on the preferential formation of isocyanic acid (HNCO) over hydrogen cyanide (HCN) and hydrogen isocyanide (HNC), thus guiding the astrobiological and chemical evolution of those distant bodies.

  11. Evaluation of Black Carbon Estimations in Global Aerosol Models

    SciTech Connect (OSTI)

    Koch, D.; Schulz, M.; Kinne, Stefan; McNaughton, C. S.; Spackman, J. R.; Balkanski, Y.; Bauer, S.; Berntsen, T.; Bond, Tami C.; Boucher, Olivier; Chin, M.; Clarke, A. D.; De Luca, N.; Dentener, F.; Diehl, T.; Dubovik, O.; Easter, Richard C.; Fahey, D. W.; Feichter, J.; Fillmore, D.; Freitag, S.; Ghan, Steven J.; Ginoux, P.; Gong, S.; Horowitz, L.; Iversen, T.; Kirkevag, A.; Klimont, Z.; Kondo, Yutaka; Krol, M.; Liu, Xiaohong; Miller, R.; Montanaro, V.; Moteki, N.; Myhre, G.; Penner, J.; Perlwitz, Ja; Pitari, G.; Reddy, S.; Sahu, L.; Sakamoto, H.; Schuster, G.; Schwarz, J. P.; Seland, O.; Stier, P.; Takegawa, Nobuyuki; Takemura, T.; Textor, C.; van Aardenne, John; Zhao, Y.

    2009-11-27

    We evaluate black carbon (BC) model predictions from the AeroCom model intercomparison project by considering the diversity among year 2000 model simulations and comparing model predictions with available measurements. These model-measurement intercomparisons include BC surface and aircraft concentrations, aerosol absorption optical depth (AAOD) from AERONET and OMI retrievals and BC column estimations based on AERONET. In regions other than Asia, most models are biased high compared to surface concentration measurements. However compared with (column) AAOD or BC burden retreivals, the models are generally biased low. The average ratio of model to retrieved AAOD is less than 0.7 in South American and 0.6 in African biomass burning regions; both of these regions lack surface concentration measurements. In Asia the average model to observed ratio is 0.6 for AAOD and 0.5 for BC surface concentrations. Compared with aircraft measurements over the Americas at latitudes between 0 and 50N, the average model is a factor of 10 larger than observed, and most models exceed the measured BC standard deviation in the mid to upper troposphere. At higher latitudes the average model to aircraft BC is 0.6 and underestimate the observed BC loading in the lower and middle troposphere associated with springtime Arctic haze. Low model bias for AAOD but overestimation of surface and upper atmospheric BC concentrations at lower latitudes suggests that most models are underestimating BC absorption and should improve estimates for refractive index, particle size, and optical effects of BC coating. Retrieval uncertainties and/or differences with model diagnostic treatment may also contribute to the model-measurement disparity. Largest AeroCom model diversity occurred in northern Eurasia and the remote Arctic, regions influenced by anthropogenic sources. Changing emissions, aging, removal, or optical properties within a single model generated a smaller change in model predictions than the

  12. Mill Integration-Pulping, Stream Reforming and Direct Causticization for Black Liquor Recovery

    SciTech Connect (OSTI)

    Adriaan van Heiningen

    2007-06-30

    MTCI/StoneChem developed a steam reforming, fluidized bed gasification technology for biomass. DOE supported the demonstration of this technology for gasification of spent wood pulping liquor (or 'black liquor') at Georgia-Pacific's Big Island, Virginia mill. The present pre-commercial R&D project addressed the opportunities as well as identified negative aspects when the MTCI/StoneChem gasification technology is integrated in a pulp mill production facility. The opportunities arise because black liquor gasification produces sulfur (as H{sub 2}S) and sodium (as Na{sub 2}CO{sub 3}) in separate streams which may be used beneficially for improved pulp yield and properties. The negative aspect of kraft black liquor gasification is that the amount of Na{sub 2}CO{sub 3} which must be converted to NaOH (the so called causticizing requirement) is increased. This arises because sulfur is released as Na{sub 2}S during conventional kraft black liquor recovery, while during gasification the sodium associated Na{sub 2}S is partly or fully converted to Na{sub 2}CO{sub 3}. The causticizing requirement can be eliminated by including a TiO{sub 2} based cyclic process called direct causticization. In this process black liquor is gasified in the presence of (low sodium content) titanates which convert Na{sub 2}CO{sub 3} to (high sodium content) titanates. NaOH is formed when contacting the latter titanates with water, thereby eliminating the causticizing requirement entirely. The leached and low sodium titanates are returned to the gasification process. The project team comprised the University of Maine (UM), North Carolina State University (NCSU) and MTCI/ThermoChem. NCSU and MTCI are subcontractors to UM. The principal organization for the contract is UM. NCSU investigated the techno-economics of using advanced pulping techniques which fully utilize the unique cooking liquors produced by steam reforming of black liquor (Task 1). UM studied the kinetics and agglomeration problems of

  13. Noether charges and black hole mechanics in Einstein-aether theory

    SciTech Connect (OSTI)

    Foster, Brendan Z.

    2006-01-15

    The Noether charge method for defining the Hamiltonian of a diffeomorphism-invariant field theory is applied to 'Einstein-aether' theory, in which gravity couples to a dynamical, timelike, unit-norm vector field. Using the method, expressions are obtained for the total energy, momentum, and angular momentum of an Einstein-aether space-time. The method is also used to discuss the mechanics of Einstein-aether black holes. The derivation of Wald, and Iyer and Wald, of the first law of black hole thermodynamics fails for this theory because the unit-vector is necessarily singular at the bifurcation surface of the Killing horizon. A general identity relating variations of energy and angular momentum to a surface integral at the horizon is obtained, but a thermodynamic interpretation, including a definitive expression for the black hole entropy, is not found.

  14. Uniqueness theorem for Kaluza-Klein black holes in five-dimensional minimal supergravity

    SciTech Connect (OSTI)

    Tomizawa, Shinya

    2010-11-15

    We show a uniqueness theorem for Kaluza-Klein black holes in the bosonic sector of five-dimensional minimal supergravity. More precisely, under the assumptions of the existence of two commuting axial isometries and a nondegenerate connected event horizon of the cross-section topology S{sup 3}, or lens space, we prove that a stationary charged rotating Kaluza-Klein black hole in five-dimensional minimal supergravity is uniquely characterized by its mass, two independent angular momenta, electric charge, magnetic flux, and nut charge, provided that there exists neither a nut nor a bolt (a bubble) in the domain of outer communication. We also show that under the assumptions of the same symmetry, same asymptotics, and the horizon cross section of S{sup 1}xS{sup 2}, a black ring within the same theory--if it exists--is uniquely determined by its dipole charge and rod intervals besides the charges and magnetic flux.

  15. Inflation Induced Planck-Size Black Hole Remnants as Dark Matter

    SciTech Connect (OSTI)

    Chen, P

    2004-07-06

    While there exist various candidates, the identification of dark matter remains unresolved. Recently it was argued that the generalized uncertainty principle (GUP) may prevent a black hole from evaporating completely, and as a result there should exist a Planck-size BHR at the end of its evaporation. We speculate that the stability of BHR may be further protected by supersymmetry in the form of extremal black hole. If this is indeed the case and if a sufficient amount of small black holes can be produced in the early universe, then the resultant BHRs can be an interesting candidate for DM. We demonstrate that this is the case in the hybrid inflation model. By assuming BHR as DM, our notion imposes a constraint on the hybrid inflation potential. We show that such a constraint is not fine-tuned. Possible observational signatures are briefly discussed.

  16. Gravitational waves from the collision of tidally disrupted stars with massive black holes

    SciTech Connect (OSTI)

    East, William E.

    2014-11-10

    We use simulations of hydrodynamics coupled with full general relativity to investigate the gravitational waves produced by a star colliding with a massive black hole when the star's tidal disruption radius lies far outside of the black hole horizon. We consider both main-sequence and white-dwarf compaction stars, and nonspinning black holes, as well as those with near-extremal spin. We study the regime in between where the star can be accurately modeled by a point particle, and where tidal effects completely suppress the gravitational wave signal. We find that nonnegligible gravitational waves can be produced even when the star is strongly affected by tidal forces, as well as when it collides with large angular momentum. We discuss the implications that these results have for the potential observation of gravitational waves from these sources with future detectors.

  17. Violation of the first law of black hole thermodynamics in f(T) gravity

    SciTech Connect (OSTI)

    Miao, Rong-Xin; Li, Miao; Miao, Yan-Gang E-mail: mli@itp.ac.cn

    2011-11-01

    We prove that, in general, the first law of black hole thermodynamics, ?Q = T?S, is violated in f(T) gravity. As a result, it is possible that there exists entropy production, which implies that the black hole thermodynamics can be in non-equilibrium even in the static spacetime. This feature is very different from that of f(R) or that of other higher derivative gravity theories. We find that the violation of first law results from the lack of local Lorentz invariance in f(T) gravity. By investigating two examples, we note that f''(0) should be negative in order to avoid the naked singularities and superluminal motion of light. When f''(T) is small, the entropy of black holes in f(T) gravity is approximatively equal to f'(T)/4 A.

  18. The Equations of Motion of Compact Binaries in the Neighborhood of Supermassive Black Hole

    SciTech Connect (OSTI)

    Gorbatsievich, Alexander; Bobrik, Alexey

    2010-03-24

    By the use of Einstein-Infeld-Hoffmann method, the equations of motion of a binary star system in the field of a supermassive black hole are derived. In spite of the fact that the motion of a binary system as a whole can be relativistic or even ultra-relativistic with respect to the supermassive black hole, it is shown, that under the assumption of non-relativistic relative motion of the stars in binary system, the motion of the binary system as a whole satisfies the Mathisson-Papapetrou equations with additional terms depending on quadrupole moments. Exemplary case of ultrarelativistic motion of a binary neutron star in the vicinity of non-rotating black hole is considered. It it shown that the motion of binary's center of mass may considerably differ from geodesic motion.

  19. Stable and 'bounded excursion' gravastars, and black holes in Einstein's theory of gravity

    SciTech Connect (OSTI)

    Rocha, P; Da Silva, M F A; Wang, Anzhong; Chan, R E-mail: chan@on.br E-mail: anzhong_wang@baylor.edu

    2008-11-15

    Dynamical models of prototype gravastars are constructed and studied. The models are the Visser-Wiltshire three-layer gravastars, in which an infinitely thin spherical shell of a perfect fluid with the equation of state p = (1-{gamma}){sigma} divides the whole spacetime into two regions, where the internal region is de Sitter, and the external one is Schwarzschild. When {gamma}<1 and {Lambda}{ne}0, it is found that in some cases the models represent stable gravastars, and in some cases they represent 'bounded excursion' stable gravastars, where the thin shell is oscillating between two finite radii, while in some other cases they collapse until the formation of black holes occurs. However, when {gamma}{>=}1, even with {Lambda}{ne}0, only black holes are found. In the phase space, the region for both stable gravastars and 'bounded excursion' gravastars is very small in comparison to that for black holes, although it is not completely empty.

  20. SPIN-PRECESSION: BREAKING THE BLACK HOLE-NEUTRON STAR DEGENERACY

    SciTech Connect (OSTI)

    Chatziioannou, Katerina; Cornish, Neil; Klein, Antoine; Yunes, Nicols

    2015-01-01

    Mergers of compact stellar remnants are prime targets for the LIGO/Virgo gravitational wave detectors. The gravitational wave signals from these merger events can be used to study the mass and spin distribution of stellar remnants, and provide information about black hole horizons and the material properties of neutron stars. However, it has been suggested that degeneracies in the way that the star's mass and spin are imprinted in the waveforms may make it impossible to distinguish between black holes and neutron stars. Here we show that the precession of the orbital plane due to spin-orbit coupling breaks the mass-spin degeneracy, and allows us to distinguish between standard neutron stars and alternative possibilities, such as black holes or exotic neutron stars with large masses and spins.

  1. A population of relic intermediate-mass black holes in the halo of the Milky Way

    SciTech Connect (OSTI)

    Rashkov, Valery; Madau, Piero

    2014-01-10

    If 'seed' central black holes were common in the subgalactic building blocks that merged to form present-day massive galaxies, then relic intermediate-mass black holes (IMBHs) should be present in the Galactic bulge and halo. We use a particle tagging technique to dynamically populate the N-body Via Lactea II high-resolution simulation with black holes, and assess the size, properties, and detectability of the leftover population. The method assigns a black hole to the most tightly bound central particle of each subhalo at infall according to an extrapolation of the M {sub BH}-?{sub *} relation, and self-consistently follows the accretion and disruption of Milky Way progenitor dwarfs and their holes in a cosmological 'live' host from high redshift to today. We show that, depending on the minimum stellar velocity dispersion, ? {sub m}, below which central black holes are assumed to be increasingly rare, as many as ?2000 (? {sub m} = 3 km s{sup 1}) or as few as ?70 (? {sub m} = 12 km s{sup 1}) IMBHs may be left wandering in the halo of the Milky Way today. The fraction of IMBHs forced from their hosts by gravitational recoil is ? 20%. We identify two main Galactic subpopulations, 'naked' IMBHs, whose host subhalos were totally destroyed after infall, and 'clothed' IMBHs residing in dark matter satellites that survived tidal stripping. Naked IMBHs typically constitute 40%-50% of the total and are more centrally concentrated. We show that, in the ? {sub m} = 12 km s{sup 1} scenario, the clusters of tightly bound stars that should accompany naked IMBHs would be fainter than m{sub V} = 16 mag, spatially resolvable, and have proper motions of 0.1-10 mas yr{sup 1}. Their detection may provide an observational tool to constrain the formation history of massive black holes in the early universe.

  2. Hidden conformal symmetry of rotating black holes in minimal five-dimensional gauged supergravity

    SciTech Connect (OSTI)

    Setare, M. R.; Kamali, V.

    2010-10-15

    In the present paper we show that for a low frequency limit the wave equation of a massless scalar field in the background of nonextremal charged rotating black holes in five-dimensional minimal gauged and ungauged supergravity can be written as the Casimir of an SL(2,R) symmetry. Our result shows that the entropy of the black hole is reproduced by the Cardy formula. Also the absorption cross section is consistent with the finite temperature absorption cross section for a two-dimensional conformal field theory.

  3. Comparative results of the combustion of lignin briquettes and black coal

    SciTech Connect (OSTI)

    V.G. Lurii

    2008-12-15

    A new type of biofuel - hydrolytic lignin briquettes - was tested as compared with ordinary SS coal from the Kuznetsk Basin in fuel-bed firing in a Universal-6 boiler. It was found that the (total) efficiency of the boiler with the firing of lignin briquettes was 38% higher than that with the use of black coal. Carbon loss in the combustion of briquettes was 1%, whereas it was 48.2% in the combustion of black coal. The emission of harmful gas pollutants into the environment in the combustion of briquettes was lower than that in the combustion of coal by a factor of 4.5.

  4. In Celebration of Black History Month, Energy Secretary Moniz and Director

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    of the National Museum of African Art Dr. Cole Discuss the Art of Science | Department of Energy In Celebration of Black History Month, Energy Secretary Moniz and Director of the National Museum of African Art Dr. Cole Discuss the Art of Science In Celebration of Black History Month, Energy Secretary Moniz and Director of the National Museum of African Art Dr. Cole Discuss the Art of Science February 23, 2015 - 1:50am Addthis News Media Contact 202 586 4940 RSVP@hq.doe.gov In Celebration of

  5. Are You Planning to Buy Energy-Efficient Products on Black Friday? |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy Are You Planning to Buy Energy-Efficient Products on Black Friday? Are You Planning to Buy Energy-Efficient Products on Black Friday? November 23, 2011 - 5:09am Addthis This week, Chris gave us some great information on shopping for energy-efficient products. He reminded us that the cost to run appliances and home office and electronics is just as important as the purchase price, and posted a new Energy Savers graphic that shows you how to read the EnergyGuide and Energy

  6. A comprehensive program to develop correlations for physical properties of kraft black liquor. Final report

    SciTech Connect (OSTI)

    Fricke, A.L.; Zaman, A.A.

    1998-05-01

    The overall objective of the program was to develop correlations to predict physical properties within requirements of engineering precision from a knowledge of pulping conditions and of kraft black liquor composition, if possible. These correlations were to include those relating thermodynamic properties to pulping conditions and liquor composition. The basic premise upon which the research was based is the premise that black liquor behaves as a polymer solution. This premise has proven to be true, and has been used successfully in developing data reduction methods and in interpreting results. A three phase effort involving pulping, analysis of liquor composition, and measurement of liquor properties was conducted.

  7. Bounding the Role of Black Carbon in the Climate System: A Scientific Assessment

    SciTech Connect (OSTI)

    Bond, Tami C.; Doherty, Sarah J.; Fahey, D. W.; Forster, Piers; Berntsen, T.; DeAngelo, B. J.; Flanner, M. G.; Ghan, Steven J.; Karcher, B.; Koch, Dorothy; Kinne, Stefan; Kondo, Yutaka; Quinn, P. K.; Sarofim, Marcus; Schultz, Martin; Schulz, M.; Venkataraman, C.; Zhang, Hua; Zhang, Shiqiu; Bellouin, N.; Guttikunda, S. K.; Hopke, P. K.; Jacobson, M. Z.; Kaiser, J. W.; Klimont, Z.; Lohmann, U.; Schwarz, Joshua P.; Shindell, Drew; Storelvmo, Trude; Warren, Stephen G.; Zender, C. S.

    2013-06-06

    Black carbon aerosol plays a unique and important role in Earth’s climate system. Black carbon is a type of carbonaceous material with a unique combination of physical properties. Predominant sources are combustion related; namely, fossil fuels for transportation, solid fuels for industrial and residential uses, and open burning of biomass. Total global emissions of black carbon using bottom-up inventory methods are 7500 Gg yr-1 in the year 2000 with an uncertainty range of 2000 to 29000. This assessment provides an evaluation of black-carbon climate forcing that is comprehensive in its inclusion of all known and relevant processes and that is quantitative in providing best estimates and uncertainties of the main forcing terms: direct solar absorption, influence on liquid, mixed-phase, and ice clouds, and deposition on snow and ice. These effects are calculated with models, but when possible, they are evaluated with both microphysical measurements and field observations. Global atmospheric absorption attributable to black carbon is too low in many models, and should be increased by about about 60%. After this scaling, the best estimate for the industrial-era (1750 to 2005) direct radiative forcing of black carbon is +0.43 W m-2 with 90% uncertainty bounds of (+0.17, +0.68) W m-2. Total direct forcing by all black carbon sources in the present day is estimated as +0.49 (+0.20, +0.76) W m-2. Direct radiative forcing alone does not capture important rapid adjustment mechanisms. A framework is described and used for quantifying climate forcings and their rapid responses and feedbacks. The best estimate of industrial-era (1750 to 2005) climate forcing of black carbon through all forcing mechanisms is +0.77 W m-2 with 90% uncertainty bounds of +-0.06 to +1.53 W m-2. Thus, there is a 96% probability that black carbon emissions, independent of co-emitted species, have a positive forcing and warm the climate. With a value of +0.77 W m-2, black carbon is likely the second

  8. Overspinning a nearly extreme black hole and the weak cosmic censorship conjecture

    SciTech Connect (OSTI)

    Richartz, Mauricio; Saa, Alberto

    2008-10-15

    We revisit here the recent proposal for overspinning a nearly extreme black hole by means of a quantum tunneling process. We show that electrically neutral massless fermions evade possible backreaction effects related to superradiance, confirming the view that it would be indeed possible to form a naked singularity due to quantum effects.

  9. Time delay and magnification centroid due to gravitational lensing by black holes and naked singularities

    SciTech Connect (OSTI)

    Virbhadra, K. S.; Keeton, C. R.

    2008-06-15

    We model the massive dark object at the center of the Galaxy as a Schwarzschild black hole as well as Janis-Newman-Winicour naked singularities, characterized by the mass and scalar charge parameters, and study gravitational lensing (particularly time delay, magnification centroid, and total magnification) by them. We find that the lensing features are qualitatively similar (though quantitatively different) for Schwarzschild black holes, weakly naked, and marginally strongly naked singularities. However, the lensing characteristics of strongly naked singularities are qualitatively very different from those due to Schwarzschild black holes. The images produced by Schwarzschild black hole lenses and weakly naked and marginally strongly naked singularity lenses always have positive time delays. On the other hand, strongly naked singularity lenses can give rise to images with positive, zero, or negative time delays. In particular, for a large angular source position the direct image (the outermost image on the same side as the source) due to strongly naked singularity lensing always has a negative time delay. We also found that the scalar field decreases the time delay and increases the total magnification of images; this result could have important implications for cosmology. As the Janis-Newman-Winicour metric also describes the exterior gravitational field of a scalar star, naked singularities as well as scalar star lenses, if these exist in nature, will serve as more efficient cosmic telescopes than regular gravitational lenses.

  10. Thermodynamics of rotating charged black branes in third order lovelock gravity and the counterterm method

    SciTech Connect (OSTI)

    Dehghani, M.H.; Mann, R.B.

    2006-05-15

    We generalize the quasilocal definition of the stress-energy tensor of Einstein gravity to the case of third order Lovelock gravity, by introducing the surface terms that make the action well-defined. We also introduce the boundary counterterm that removes the divergences of the action and the conserved quantities of the solutions of third order Lovelock gravity with zero curvature boundary at constant t and r. Then, we compute the charged rotating solutions of this theory in n+1 dimensions with a complete set of allowed rotation parameters. These charged rotating solutions present black hole solutions with two inner and outer event horizons, extreme black holes or naked singularities provided the parameters of the solutions are suitably chosen. We compute temperature, entropy, charge, electric potential, mass and angular momenta of the black hole solutions, and find that these quantities satisfy the first law of thermodynamics. We find a Smarr-type formula and perform a stability analysis by computing the heat capacity and the determinant of Hessian matrix of mass with respect to its thermodynamic variables in both the canonical and the grand-canonical ensembles, and show that the system is thermally stable. This is commensurate with the fact that there is no Hawking-Page phase transition for black objects with zero curvature horizon.

  11. Black holes in an asymptotically safe gravity theory with higher derivatives

    SciTech Connect (OSTI)

    Cai, Yi-Fu; Easson, Damien A. E-mail: easson@asu.edu

    2010-09-01

    We present a class of spherically symmetric vacuum solutions to an asymptotically safe theory of gravity containing high-derivative terms. We find quantum corrected Schwarzschild-(anti)-de Sitter solutions with running gravitational coupling parameters. The evolution of the couplings is determined by their corresponding renormalization group flow equations. These black holes exhibit properties of a classical Schwarzschild solution at large length scales. At the center, the metric factor remains smooth but the curvature singularity, while softened by the quantum corrections, persists. The solutions have an outer event horizon and an inner Cauchy horizon which equate when the physical mass decreases to a critical value. Super-extremal solutions with masses below the critical value correspond to naked singularities. The Hawking temperature of the black hole vanishes when the physical mass reaches the critical value. Hence, the black holes in the asymptotically safe gravitational theory never completely evaporate. For appropriate values of the parameters such stable black hole remnants make excellent dark matter candidates.

  12. Entropy of near-extremal black holes in AdS5

    SciTech Connect (OSTI)

    Simon, Joan; Balasubramanian, Vijay; de Boer, Jan; Jejjala, Vishnu; Simon, Joan

    2007-07-24

    We construct the microstates of near-extremal black holes in AdS_5 x S5 as gases of defects distributed in heavy BPS operators in the dual SU(N) Yang-Mills theory. These defects describe open strings on spherical D3-branes in the S5, and we show that they dominate the entropy by directly enumerating them and comparing the results with a partition sum calculation. We display new decoupling limits in which the field theory of the lightest open strings on the D-branes becomes dual to a near-horizon region of the black hole geometry. In the single-charge black hole we find evidence for an infrared duality between SU(N) Yang-Mills theories that exchanges the rank of the gauge group with an R-charge. In the two-charge case (where pairs of branes intersect on a line), the decoupled geometry includes an AdS_3 factor with a two-dimensional CFT dual. The degeneracy in this CFT accounts for the black hole entropy. In the three-charge case (where triples of branes intersect at a point), the decoupled geometry contains an AdS_2 factor. Below a certain critical mass, the two-charge system displays solutions with naked timelike singularities even though they do not violate a BPS bound. We suggest a string theoretic resolution of these singularities.

  13. Summation over histories for a particle in spherical orbit around a black hole

    SciTech Connect (OSTI)

    Bernido, C.C.; Aguarte, G.

    1997-08-01

    An exact path integral treatment of a relativistic scalar particle in a spherical orbit around a Reissner-Nordstr{umlt o}m and Schwarzschild black hole is presented. A closed form for the Green function and the energy spectrum are obtained. {copyright} {ital 1997} {ital The American Physical Society}

  14. Cold black holes in the Harlow–Hayden approach to firewalls

    SciTech Connect (OSTI)

    Ong, Yen Chin; McInnes, Brett; Chen, Pisin

    2014-12-31

    Firewalls are controversial principally because they seem to imply departures from general relativistic expectations in regions of spacetime where the curvature need not be particularly large. One of the virtues of the Harlow–Hayden approach to the firewall paradox, concerning the time available for decoding of Hawking radiation emanating from charged AdS black holes, is precisely that it operates in the context of cold black holes, which are not strongly curved outside the event horizon. Here we clarify this point. The approach is based on ideas borrowed from applications of the AdS/CFT correspondence to the quark–gluon plasma. Firewalls aside, our work presents a detailed analysis of the thermodynamics and evolution of evaporating charged AdS black holes with flat event horizons. We show that, in one way or another, these black holes are always eventually destroyed in a time which, while long by normal standards, is short relative to the decoding time of Hawking radiation.

  15. Cold black holes in the Harlow–Hayden approach to firewalls

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ong, Yen Chin; McInnes, Brett; Chen, Pisin

    2014-12-31

    Firewalls are controversial principally because they seem to imply departures from general relativistic expectations in regions of spacetime where the curvature need not be particularly large. One of the virtues of the Harlow–Hayden approach to the firewall paradox, concerning the time available for decoding of Hawking radiation emanating from charged AdS black holes, is precisely that it operates in the context of cold black holes, which are not strongly curved outside the event horizon. Here we clarify this point. The approach is based on ideas borrowed from applications of the AdS/CFT correspondence to the quark–gluon plasma. Firewalls aside, our workmore » presents a detailed analysis of the thermodynamics and evolution of evaporating charged AdS black holes with flat event horizons. We show that, in one way or another, these black holes are always eventually destroyed in a time which, while long by normal standards, is short relative to the decoding time of Hawking radiation.« less

  16. Conveyor-belt clock synchronization

    SciTech Connect (OSTI)

    Giovannetti, Vittorio; Maccone, Lorenzo; Shapiro, Jeffrey H.; Wong, Franco N.C.; Lloyd, Seth

    2004-10-01

    A protocol for synchronizing distant clocks is proposed that does not rely on the arrival times of the signals which are exchanged, and an optical implementation based on coherent-state pulses is described. This protocol is not limited by any dispersion that may be present in the propagation medium through which the light signals are exchanged. Possible improvements deriving from the use of quantum-mechanical effects are also addressed.

  17. Technical Report Cellulosic Based Black Liquor Gasification and Fuels Plant Final Technical Report

    SciTech Connect (OSTI)

    Fornetti, Micheal; Freeman, Douglas

    2012-10-31

    The Cellulosic Based Black Liquor Gasification and Fuels Plant Project was developed to construct a black liquor to Methanol biorefinery in Escanaba, Michigan. The biorefinery was to be co-located at the existing pulp and paper mill, NewPage’s Escanaba Paper Mill and when in full operation would: • Generate renewable energy for Escanaba Paper Mill • Produce Methanol for transportation fuel of further refinement to Dimethyl Ether • Convert black liquor to white liquor for pulping. Black liquor is a byproduct of the pulping process and as such is generated from abundant and renewable lignocellulosic biomass. The biorefinery would serve to validate the thermochemical pathway and economic models for black liquor gasification. It was a project goal to create a compelling new business model for the pulp and paper industry, and support the nation’s goal for increasing renewable fuels production and reducing its dependence on foreign oil. NewPage Corporation planned to replicate this facility at other NewPage Corporation mills after this first demonstration scale plant was operational and had proven technical and economic feasibility. An overview of the process begins with black liquor being generated in a traditional Kraft pulping process. The black liquor would then be gasified to produce synthesis gas, sodium carbonate and hydrogen sulfide. The synthesis gas is then cleaned with hydrogen sulfide and carbon dioxide removed, and fed into a Methanol reactor where the liquid product is made. The hydrogen sulfide is converted into polysulfide for use in the Kraft pulping process. Polysulfide is a known additive to the Kraft process that increases pulp yield. The sodium carbonate salts are converted to caustic soda in a traditional recausticizing process. The caustic soda is then part of the white liquor that is used in the Kraft pulping process. Cellulosic Based Black Liquor Gasification and Fuels Plant project set out to prove that black liquor gasification could

  18. Black liquor combustion validated recovery boiler modeling, five-year report

    SciTech Connect (OSTI)

    Grace, T.M.; Frederick, W.J.; Salcudean, M.; Wessel, R.A.

    1996-08-01

    The objective of this project was to develop a new computer model of a recovery boiler furnace using a computational fluid dynamics (CFD) code specifically tailored to the requirements for solving recovery boiler flows, and using improved submodels for black liquor combustion based on continued laboratory fundamental studies. The project originated in October 1990 and was scheduled to run for four years. At that time, there was considerable emphasis on developing accurate predictions of the physical carryover of macroscopic particles of partially burnt black liquor and smelt droplets out of the furnace, since this was seen as the main cause of boiler plugging. This placed a major emphasis on gas flow patterns within the furnace and on the mass loss rates and swelling and shrinking rates of burning black liquor drops. As work proceeded on developing the recovery boiler furnace model, it became apparent that some recovery boilers encounter serious plugging problems even when physical carryover was minimal. After the original four-year period was completed, the project was extended to address this issue. The objective of the extended project was to improve the utility of the models by including the black liquor chemistry relevant to air emissions predictions and aerosol formation, and by developing the knowledge base and computational tools to relate furnace model outputs to fouling and plugging of the convective sections of the boilers. The work done to date includes CFD model development and validation, acquisition of information on black liquor combustion fundamentals and development of improved burning models, char bed model development, and model application and simplification.

  19. Model predictions of the results of interferometric observations for stars under conditions of strong gravitational scattering by black holes and wormholes

    SciTech Connect (OSTI)

    Shatskiy, A. A. Kovalev, Yu. Yu.; Novikov, I. D.

    2015-05-15

    The characteristic and distinctive features of the visibility amplitude of interferometric observations for compact objects like stars in the immediate vicinity of the central black hole in our Galaxy are considered. These features are associated with the specifics of strong gravitational scattering of point sources by black holes, wormholes, or black-white holes. The revealed features will help to determine the most important topological characteristics of the central object in our Galaxy: whether this object possesses the properties of only a black hole or also has characteristics unique to wormholes or black-white holes. These studies can be used to interpret the results of optical, infrared, and radio interferometric observations.

  20. Paleoecology of the Devonian-Mississippian black-shale sequence in eastern Kentucky with an atlas of some common fossils

    SciTech Connect (OSTI)

    Barron, L.S.; Ettensohn, F.R.

    1981-04-01

    The Devonian-Mississippian black-shale sequence of eastern North America is a distinctive stratigraphic interval generally characterized by low clastic influx, high organic production in the water column, anaerobic bottom conditions, and the relative absence of fossil evidence for biologic activity. The laminated black shales which constitute most of the black-shale sequence are broken by two major sequences of interbedded greenish-gray, clayey shales which contain bioturbation and pyritized micromorph invertebrates. The black shales contain abundant evidence of life from upper parts of the water column such as fish fossils, conodonts, algae and other phytoplankton; however, there is a lack of evidence of benthic life. The rare brachiopods, crinoids, and molluscs that occur in the black shales were probably epiplanktic. A significant physical distinction between the environment in which the black sediments were deposited and that in which the greenish-gray sediments were deposited was the level of dissolved oxygen. The laminated black shales point to anaerobic conditions and the bioturbated greenish-gray shales suggest dysaerobic to marginally aerobic-dysaerobic conditions. A paleoenvironmental model in which quasi-estuarine circulation compliments and enhances the effect of a stratified water column can account for both depletion of dissolved oxygen in the bottom environments and the absence of oxygen replenishment during black-shale deposition. Periods of abundant clastic influx from fluvial environments to the east probably account for the abundance of clays in the greenish-gray shale as well as the small amounts of oxygen necessary to support the depauparate, opportunistic, benthic faunas found there. These pulses of greenish-gray clastics were short-lived and eventually were replaced by anaerobic conditions and low rates of clastic sedimentation which characterized most of black-shale deposition.

  1. Charged annular disks and Reissner-Nordstroem type black holes from extremal dust

    SciTech Connect (OSTI)

    Lora-Clavijo, F. D.; Ospina-Henao, P. A.; Pedraza, J. F.

    2010-10-15

    We present the first analytical superposition of a charged black hole with an annular disk of extremal dust. In order to obtain the solutions, we first solve the Einstein-Maxwell field equations for sources that represent disklike configurations of matter in confomastatic spacetimes by assuming a functional dependence among the metric function, the electric potential, and an auxiliary function, which is taken as a solution of the Laplace equation. We then employ the Lord Kelvin inversion method applied to models of finite extension in order to obtain annular disks. The structures obtained extend to infinity, but their total masses are finite and all the energy conditions are satisfied. Finally, we observe that the extremal Reissner-Nordstroem black hole can be embedded into the center of the disks by adding a boundary term in the inversion.

  2. Black holes and neutron stars in the generalized tensor-vector-scalar theory

    SciTech Connect (OSTI)

    Lasky, Paul D.

    2009-10-15

    Bekenstein's tensor-vector-scalar (TeVeS) theory has had considerable success as a relativistic theory of modified Newtonian dynamics. However, recent work suggests that the dynamics of the theory are fundamentally flawed and numerous authors have subsequently begun to consider a generalization of TeVeS where the vector field is given by an Einstein-Aether action. Herein, I develop strong-field solutions of the generalized TeVeS theory, in particular exploring neutron stars as well as neutral and charged black holes. I find that the solutions are identical to the neutron star and black hole solutions of the original TeVeS theory, given a mapping between the parameters of the two theories, and hence provide constraints on these values of the coupling constants. I discuss the consequences of these results in detail including the stability of such spacetimes as well as generalizations to more complicated geometries.

  3. AdS Black Disk Model for Small-x Deep Inelastic Scattering

    SciTech Connect (OSTI)

    Cornalba, Lorenzo; Costa, Miguel S.; Penedones, Joao

    2010-08-13

    Using the approximate conformal invariance of QCD at high energies we consider a simple anti-de Sitter black disk model to describe saturation in deep inelastic scattering. Deep inside saturation the structure functions have the same power law scaling, F{sub T}{approx}F{sub L}{approx}x{sup -{omega}}, where {omega} is related to the expansion rate of the black disk with energy. Furthermore, the ratio F{sub L}/F{sub T} is given by the universal value (1+{omega}/3+{omega}), independently of the target. For {gamma}*-{gamma}* scattering at high energies we obtain explicit expressions and ratios for the total cross sections of transverse and longitudinal photons in terms of the single parameter {omega}.

  4. Thermodynamics of charged rotating black branes in Brans-Dicke theory with quadratic scalar field potential

    SciTech Connect (OSTI)

    Dehghani, M. H.; Pakravan, J.; Hendi, S. H.

    2006-11-15

    We construct a class of charged rotating solutions in (n+1)-dimensional Maxwell-Brans-Dicke theory with flat horizon in the presence of a quadratic potential and investigate their properties. These solutions are neither asymptotically flat nor (anti)-de Sitter. We find that these solutions can present black brane, with inner and outer event horizons, an extreme black brane or a naked singularity provided the parameters of the solutions are chosen suitably. We compute the finite Euclidean action through the use of counterterm method, and obtain the conserved and thermodynamic quantities by using the relation between the action and free energy in grand-canonical ensemble. We find that these quantities satisfy the first law of thermodynamics, and the entropy does not follow the area law.

  5. Black GE based on crystalline/amorphous core/shell nanoneedle arrays

    DOE Patents [OSTI]

    Javey, Ali; Chueh, Yu-Lun; Fan, Zhiyong

    2014-03-04

    Direct growth of black Ge on low-temperature substrates, including plastics and rubber is reported. The material is based on highly dense, crystalline/amorphous core/shell Ge nanoneedle arrays with ultrasharp tips (.about.4 nm) enabled by the Ni catalyzed vapor-solid-solid growth process. Ge nanoneedle arrays exhibit remarkable optical properties. Specifically, minimal optical reflectance (<1%) is observed, even for high angles of incidence (.about.75.degree.) and for relatively short nanoneedle lengths (.about.1 .mu.m). Furthermore, the material exhibits high optical absorption efficiency with an effective band gap of .about.1 eV. The reported black Ge can have important practical implications for efficient photovoltaic and photodetector applications on nonconventional substrates.

  6. Gravitational signature of Schwarzschild black holes in dynamical Chern-Simons gravity

    SciTech Connect (OSTI)

    Molina, C.; Pani, Paolo; Cardoso, Vitor; Gualtieri, Leonardo

    2010-06-15

    Dynamical Chern-Simons gravity is an extension of general relativity in which the gravitational field is coupled to a scalar field through a parity-violating Chern-Simons term. In this framework, we study perturbations of spherically symmetric black hole spacetimes, assuming that the background scalar field vanishes. Our results suggest that these spacetimes are stable, and small perturbations die away as a ringdown. However, in contrast to standard general relativity, the gravitational waveforms are also driven by the scalar field. Thus, the gravitational oscillation modes of black holes carry imprints of the coupling to the scalar field. This is a smoking gun for Chern-Simons theory and could be tested with gravitational-wave detectors, such as LIGO or LISA. For negative values of the coupling constant, ghosts are known to arise, and we explicitly verify their appearance numerically. Our results are validated using both time evolution and frequency domain methods.

  7. Null geodesics and shadow of a rotating black hole in extended Chern-Simons modified gravity

    SciTech Connect (OSTI)

    Amarilla, Leonardo; Eiroa, Ernesto F.; Giribet, Gaston

    2010-06-15

    The Chern-Simons modification to general relativity in four dimensions consists of adding to the Einstein-Hilbert term a scalar field that couples to the first-class Pontryagin density. In this theory, which has attracted considerable attention recently, the Schwarzschild metric persists as an exact solution, and this is why this model resists several observational constraints. In contrast, the spinning black hole solution of the theory is not given by the Kerr metric but by a modification of it, so far only known for slow rotation and small coupling constant. In the present paper, we show that, in this approximation, the null geodesic equation can be integrated, and this allows us to investigate the shadow cast by a black hole. We discuss how, in addition to the angular momentum of the solution, the coupling to the Chern-Simons term deforms the shape of the shadow.

  8. Results from Undergraduate PV Projects at Seven Historically Black Colleges and Universities

    SciTech Connect (OSTI)

    McConnell, R. D.

    1999-03-03

    In 1995, the NREL/Department of Energy (DOE) National Photovoltaics Program funded seven Historically Black Colleges and Universities (HBCUs) in its HBCU Photovoltaic Research Associates Program for a period of three years. The program's purpose is to advance HBCU undergraduate knowledge of photovoltaics, primarily as a result of research investigations performed, and to encourage students to pursue careers in photovoltaics. This paper presents results from PV projects ranging from fundamental materials research on PV materials to field projects of PV systems.

  9. AmeriFlux US-Prr Poker Flat Research Range Black Spruce Forest

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Suzuki, Rikie [Japan Agency for Marine-Earth Science and Technology

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-Prr Poker Flat Research Range Black Spruce Forest. Site Description - This site is located in a blackspruce forest within the property of the Poker Flat Research Range, University of Alaska, Fairbanks. Time-lapse image of the canopy is measured at the same time to relate flux data to satellite images.

  10. THE TIDAL DISRUPTION OF GIANT STARS AND THEIR CONTRIBUTION TO THE FLARING SUPERMASSIVE BLACK HOLE POPULATION

    SciTech Connect (OSTI)

    MacLeod, Morgan; Guillochon, James; Ramirez-Ruiz, Enrico E-mail: jfg@ucolick.org

    2012-10-01

    Sun-like stars are thought to be regularly disrupted by supermassive black holes (SMBHs) within galactic nuclei. Yet, as stars evolve off the main sequence their vulnerability to tidal disruption increases drastically as they develop a bifurcated structure consisting of a dense core and a tenuous envelope. Here we present the first hydrodynamic simulations of the tidal disruption of giant stars and show that the core has a substantial influence on the star's ability to survive the encounter. Stars with more massive cores retain large fractions of their envelope mass, even in deep encounters. Accretion flares resulting from the disruption of giant stars should last for tens to hundreds of years. Their characteristic signature in transient searches would not be the t {sup -5/3} decay typically associated with tidal disruption events, but a correlated rise over many orders of magnitude in brightness on timescales of months to years. We calculate the relative disruption rates of stars of varying evolutionary stages in typical galactic centers, then use our results to produce Monte Carlo realizations of the expected flaring event populations. We find that the demographics of tidal disruption flares are strongly dependent on both stellar and black hole mass, especially near the limiting SMBH mass scale of {approx}10{sup 8} M{sub Sun }. At this black hole mass, we predict a sharp transition in the SMBH flaring diet beyond which all observable disruptions arise from evolved stars, accompanied by a dramatic cutoff in the overall tidal disruption flaring rate. Black holes less massive than this limiting mass scale will show observable flares from both main-sequence and evolved stars, with giants contributing up to 10% of the event rate. The relative fractions of stars disrupted at different evolutionary states can constrain the properties and distributions of stars in galactic nuclei other than our own.

  11. Hydrogen atom donor compounds as contrast enhancers for black-and-white photothermographic and thermographic elements

    DOE Patents [OSTI]

    Harring, Lori S.; Simpson, Sharon M.; Sansbury, Francis H.

    1997-01-01

    Hydrogen atom donor compounds are useful as contrast enhancers when used in combination with (i) hindered phenol developers, and (ii) trityl hydrazide and/or formyl-phenyl hydrazine co-developers, to produce ultra-high contrast black-and-white photothermographic and thermographic elements. The photothermographic and thermographic elements may be used as a photomask in a process where there is a subsequent exposure of an ultraviolet or short wavelength visible radiation-sensitive imageable medium.

  12. Megaparsec relativistic jets launched from an accreting supermassive black hole in an extreme spiral galaxy

    SciTech Connect (OSTI)

    Bagchi, Joydeep; Vivek, M.; Srianand, Raghunathan; Gopal-Krishna; Vikram, Vinu; Hota, Ananda; Biju, K. G.; Sirothia, S. K.; Jacob, Joe

    2014-06-20

    The radio galaxy phenomenon is directly connected to mass-accreting, spinning supermassive black holes found in the active galactic nuclei. It is still unclear how the collimated jets of relativistic plasma on hundreds to thousands of kiloparsec scales form and why they are nearly always launched from the nuclei of bulge-dominated elliptical galaxies and not flat spirals. Here we present the discovery of the giant radio source J23450449 (z = 0.0755), a clear and extremely rare counterexample where relativistic jets are ejected from a luminous and massive spiral galaxy on a scale of ?1.6 Mpc, the largest known so far. Extreme physical properties observed for this bulgeless spiral host, such as its high optical and infrared luminosity, large dynamical mass, rapid disk rotation, and episodic jet activity, are possibly the results of its unusual formation history, which has also assembled, via gas accretion from a disk, its central black hole of mass >2 10{sup 8} M {sub ?}. The very high mid-IR luminosity of the galaxy suggests that it is actively forming stars and still building a massive disk. We argue that the launch of these powerful jets is facilitated by an advection-dominated, magnetized accretion flow at a low Eddington rate onto this unusually massive (for a bulgeless disk galaxy) and possibly fast spinning central black hole. Therefore, J23450449 is an extremely rare, unusual galactic system whose properties challenge the standard paradigms for black hole growth and the formation of relativistic jets in disk galaxies. Thus, it provides fundamental insight into accretion disk-relativistic jet coupling processes.

  13. String loops in the field of braneworld spherically symmetric black holes and naked singularities

    SciTech Connect (OSTI)

    Stuchlk, Z.; Kolo, M. E-mail: martin.kolos@fpf.slu.cz

    2012-10-01

    We study motion of current-carrying string loops in the field of braneworld spherically symmetric black holes and naked singularities. The spacetime is described by the Reissner-Nordstrm geometry with tidal charge b reflecting the non-local tidal effects coming from the external dimension; both positive and negative values of the spacetime parameter b are considered. We restrict attention to the axisymmetric motion of string loops when the motion can be fully governed by an appropriately defined effective potential related to the energy and angular momentum of the string loops. In dependence on these two constants of the motion, the string loops can be captured, trapped, or can escape to infinity. In close vicinity of stable equilibrium points at the centre of trapped states the motion is regular. We describe how it is transformed to chaotic motion with growing energy of the string loop. In the field of naked singularities the trapped states located off the equatorial plane of the system exist and trajectories unable to cross the equatorial plane occur, contrary to the trajectories in the field of black holes where crossing the equatorial plane is always admitted. We concentrate our attention to the so called transmutation effect when the string loops are accelerated in the deep gravitational field near the black hole or naked singularity by transforming the oscillatory energy to the energy of the transitional motion. We demonstrate that the influence of the tidal charge can be substantial especially in the naked singularity spacetimes with b > 1 where the acceleration to ultrarelativistic velocities with Lorentz factor ? ? 100 can be reached, being more than one order higher in comparison with those obtained in the black hole spacetimes.

  14. Synthesis and characterization of black, red and yellow nanoparticles pigments from the iron sand

    SciTech Connect (OSTI)

    Mufti, Nandang Atma, T. Fuad, A.; Sutadji, E.

    2014-09-25

    The aim of this research is to synthesize nanoparticles of black pigment of Magnetite (Fe{sub 3}O{sub 4}), red pigment of hematite (α-Fe{sub 2}O{sub 3}), and yellow pigment of ghoetite (α-FeOOH) from the iron sand. The black pigment of Fe{sub 3}O{sub 4} and the yellow pigment α-FeOOH nanoparticles were synthesized by coprecipitation method with variation of pH. Whereas, the red pigment Fe{sub 2}O{sub 3} was synthesized by sintering Fe{sub 3}O{sub 4} nanoparticles at temperature between 400 °C and 700 7°C for 1 hour. All the pigments has been characterized using X-ray diffraction and SEM. The XRD results shown that the particle size of the black pigmen Fe{sub 3}O{sub 4}, red pigment Fe{sub 3}O{sub 4} and yellow pigment α-FeOOH are around 12, 32, and 30 nm respectively. The particle size of Fe{sub 2}O{sub 3} nanoparticles increase by increasing sintering temperature from 32 nm at 400 °C to 39 nm at 700 °C. For yellow pigment of α-FeOOH, the particle size increase by increasing pH from 30,54 nm at pH 4 to 48,60 nm at pH 7. The SEM results shown that the morphologies of black, yellow and red pigments are aglomarated.

  15. The Neutrino Signal from Protoneutron Star Accretion and Black Hole Formation

    SciTech Connect (OSTI)

    Fischer, T.; Whitehouse, S.; Mezzacappa, Anthony; Thielemann, F.-K.; Liebendoerfer, M.

    2009-01-01

    We discuss the formation of stellar mass black holes via protoneutron star (PNS) collapse. In the absence of an earlier explosion, the PNS collapses to a black hole due to the continued mass accretion onto the PNS. We present an analysis of the emitted neutrino spectra of all three flavors during the PNS contraction. Special attention is given to the physical conditions which depend on the input physics, e.g. the equation of state (EoS) and the progenitor model. The PNSs are modeled as the central object in core collapse simulations using general relativistic three-flavor Boltzmann neutrino transport in spherical symmetry. The simulations are launched from several massive progenitors of 40 M{omicron} and 50 M{omicron}. We analyze the electron-neutrino luminosity dependencies and construct a simple approximation for the electron-neutrino luminosity, which depends only on the physical conditions at the electron-neutrinosphere. In addition, we analyze different ({mu}, {tau})-neutrino pair-reactions separately and compare the differences during the post-bounce phases of failed core collapse supernova explosions of massive progenitors. We also investigate the connection between the increasing {mu},{tau}-neutrino luminosity and the PNS contraction during the accretion phase before black hole formation. Comparing the different post bounce phases of the progenitor models under investigation, we find large differences in the emitted neutrino spectra. These differences and the analysis of the electron-neutrino luminosity indicate a strong progenitor model dependency of the emitted neutrino signal.

  16. The mass of the central black hole in the nearby Seyfert galaxy NGC 5273

    SciTech Connect (OSTI)

    Bentz, Misty C.; Horenstein, Daniel; Bazhaw, Craig; Manne-Nicholas, Emily R.; Ou-Yang, Benjamin J.; Anderson, Matthew; Jones, Jeremy; Norris, Ryan P.; Parks, J. Robert; Saylor, Dicy; Teems, Katherine G.; Turner, Clay

    2014-11-20

    We present the results of a reverberation-mapping program targeting NGC 5273, a nearby early-type galaxy with a broad-lined active galactic nucleus (AGN). Over the course of the monitoring program, NGC 5273 showed strong variability that allowed us to measure time delays in the responses of the broad optical recombination lines to changes in the continuum flux. A weighted average of these measurements results in a black hole mass determination of M {sub BH} = (4.7 ± 1.6) × 10{sup 6} M {sub ☉}. An estimate of the size of the black hole sphere of influence in NGC 5273 puts it just at the limit of the resolution achievable with current ground-based large aperture telescopes. NGC 5273 is therefore an important future target for a black hole mass determination from stellar dynamical modeling, especially because it is the only nearby early-type galaxy hosting an AGN with a reverberation-based mass, allowing the best comparison for the masses determined from these two techniques.

  17. 17.1%-Efficient Multi-Scale-Textured Black Silicon Solar Cells without Dielectric Antireflection Coating

    SciTech Connect (OSTI)

    Toor, F.; Page, M. R.; Branz, H. M.; Yuan, H. C.

    2011-01-01

    In this work we present 17.1%-efficient p-type single crystal Si solar cells with a multi-scale-textured surface and no dielectric antireflection coating. Multi-scale texturing is achieved by a gold-nanoparticle-assisted nanoporous etch after conventional micron scale KOH-based pyramid texturing (pyramid black etching). By incorporating geometric enhancement of antireflection, this multi-scale texturing reduces the nanoporosity depth required to make silicon `black' compared to nanoporous planar surfaces. As a result, it improves short-wavelength spectral response (blue response), previously one of the major limiting factors in `black-Si' solar cells. With multi-scale texturing, the spectrum-weighted average reflectance from 350- to 1000-nm wavelength is below 2% with a 100-nm deep nanoporous layer. In comparison, roughly 250-nm deep nanopores are needed to achieve similar reflectance on planar surface. Here, we characterize surface morphology, reflectivity and solar cell performance of the multi-scale textured solar cells.

  18. UNIVERSAL BEHAVIOR OF X-RAY FLARES FROM BLACK HOLE SYSTEMS

    SciTech Connect (OSTI)

    Wang, F. Y.; Dai, Z. G.; Yi, S. X.; Xi, S. Q. E-mail: dzg@nju.edu.cn

    2015-01-01

    X-ray flares have been discovered in black hole systems such as gamma-ray bursts, the tidal disruption event Swift J1644+57, the supermassive black hole Sagittarius A* at the center of our Galaxy, and some active galactic nuclei. Occurrences of X-ray flares are always accompanied by relativistic jets. However, it is still unknown whether or not there is a physical analogy among such X-ray flares produced in black hole systems spanning nine orders of magnitude in mass. Here, we report observed data of X-ray flares and show that they have three statistical properties similar to solar flares, including power-law distributions of their energies, durations, and waiting times, which can be explained by a fractal-diffusive, self-organized criticality model. These statistical similarities, together with the fact that solar flares are triggered by a magnetic reconnection process, suggest that all of the X-ray flares are consistent with magnetic reconnection events, implying that their concomitant relativistic jets may be magnetically dominated.

  19. Black liquor combustion validated recovery boiler modeling: Final year report. Volume 4 (Appendix IV)

    SciTech Connect (OSTI)

    Grace, T.M.; Frederick, W.J.; Salcudean, M.; Wessel, R.A.

    1998-08-01

    This project was initiated in October 1990, with the objective of developing and validating a new computer model of a recovery boiler furnace using a computational fluid dynamics (CFD) code specifically tailored to the requirements for solving recovery boiler flows, and using improved submodels for black liquor combustion based on continued laboratory fundamental studies. The key tasks to be accomplished were as follows: (1) Complete the development of enhanced furnace models that have the capability to accurately predict carryover, emissions behavior, dust concentrations, gas temperatures, and wall heat fluxes. (2) Validate the enhanced furnace models, so that users can have confidence in the predicted results. (3) Obtain fundamental information on aerosol formation, deposition, and hardening so as to develop the knowledge base needed to relate furnace model outputs to plugging and fouling in the convective sections of the boiler. (4) Facilitate the transfer of codes, black liquid submodels, and fundamental knowledge to the US kraft pulp industry. Volume 4 contains the following appendix sections: Radiative heat transfer properties for black liquor combustion -- Facilities and techniques and Spectral absorbance and emittance data; and Radiate heat transfer determination of the optical constants of ash samples from kraft recovery boilers -- Calculation procedure; Computation program; Density determination; Particle diameter determination; Optical constant data; and Uncertainty analysis.

  20. Application of the sup 187 Re- sup 187 Os system to black shale geochronometry

    SciTech Connect (OSTI)

    Ravizza, G.; Turekain, K.K. )

    1989-12-01

    The decay of {sup 187}Re to {sup 187}Os provides a tool for determining depositional ages of black shales. Re and Os concentrations and Os isotopic compositions of whole rock samples of the Bakken Shale, a Mississippian/Devonian boundary black shale, yield a whole rock isochron with an age of 354 {plus minus} 49 Ma. This age is in agreement with the accepted age of the Bakken Shale ({approx}360 Ma). The initial {sup 187}Os/{sup 186}Os ratio of the isochron is 6.2 {plus minus} 3.3. This value is indistinguishable from the {sup 187}Os/{sup 186}Os ratios observed in modern Black Sea sediments. The concentration of common Os in Bakken Shale samples is strongly correlated with total nitrogen, indicating that a large fraction of the Os in these samples is associated with a hydrogenous component, which overwhelms any Os supplied to the sediment in association with detrital material or cosmic dust. The dominance of the hydrogenous component imparts a relatively homogeneous initial {sup 187}Os/{sup 186}Os ratio to the sediment at the time of deposition. The degree of scatter about the isochron exceeds the degree of scatter expected from either analytical error or from the estimated degree of initial isotopic heterogeneity. The pattern of scatter is consistent with postdepositional mobilization of Re and/or Os on a small spatial scale. The author suggest that this mobilization may be a consequence of petroleum formation and migration in the Bakken Shale.

  1. Inducing chaos by breaking axial symmetry in a black hole magnetosphere

    SciTech Connect (OSTI)

    Kopáček, O.; Karas, V.

    2014-06-01

    While the motion of particles near a rotating, electrically neutral (Kerr), and charged (Kerr-Newman) black hole is always strictly regular, a perturbation in the gravitational or the electromagnetic field generally leads to chaos. The transition from regular to chaotic dynamics is relatively gradual if the system preserves axial symmetry, whereas non-axisymmetry induces chaos more efficiently. Here we study the development of chaos in an oblique (electro-vacuum) magnetosphere of a magnetized black hole. Besides the strong gravity of the massive source represented by the Kerr metric, we consider the presence of a weak, ordered, large-scale magnetic field. An axially symmetric model consisting of a rotating black hole embedded in an aligned magnetic field is generalized by allowing an oblique direction of the field having a general inclination with respect to the rotation axis of the system. The inclination of the field acts as an additional perturbation to the motion of charged particles as it breaks the axial symmetry of the system and cancels the related integral of motion. The axial component of angular momentum is no longer conserved and the resulting system thus has three degrees of freedom. Our primary concern within this contribution is to find out how sensitive the system of bound particles is to the inclination of the field. We employ the method of the maximal Lyapunov exponent to distinguish between regular and chaotic orbits and to quantify their chaoticity. We find that even a small misalignment induces chaotic motion.

  2. Thermodynamics of rotating black branes in (n+1)-dimensional Einstein-Born-Infeld gravity

    SciTech Connect (OSTI)

    Dehghani, M. H.; Sedehi, H. R. Rastegar

    2006-12-15

    We construct a new class of charged rotating solutions of (n+1)-dimensional Einstein-Born-Infeld gravity with cylindrical or toroidal horizons in the presence of cosmological constant and investigate their properties. These solutions are asymptotically (anti)-de Sitter and reduce to the solutions of Einstein-Maxwell gravity as the Born-Infeld parameters goes to infinity. We find that these solutions can represent black branes, with inner and outer event horizons, an extreme black brane or a naked singularity provided the parameters of the solutions are chosen suitably. We compute temperature, mass, angular momentum, entropy, charge and electric potential of the black brane solutions. We obtain a Smarr-type formula and show that these quantities satisfy the first law of thermodynamics. We also perform a stability analysis by computing the heat capacity and the determinant of Hessian matrix of mass of the system with infinite boundary with respect to its thermodynamic variables in both the canonical and the grand-canonical ensembles, and show that the system is thermally stable in the whole phase space. Also, we find that there exists an unstable phase when the finite size effect is taken into account.

  3. Super massive black hole in galactic nuclei with tidal disruption of stars

    SciTech Connect (OSTI)

    Zhong, Shiyan; Berczik, Peter; Spurzem, Rainer

    2014-09-10

    Tidal disruption of stars by super massive central black holes from dense star clusters is modeled by high-accuracy direct N-body simulation. The time evolution of the stellar tidal disruption rate, the effect of tidal disruption on the stellar density profile, and, for the first time, the detailed origin of tidally disrupted stars are carefully examined and compared with classic papers in the field. Up to 128k particles are used in simulation to model the star cluster around a super massive black hole, and we use the particle number and the tidal radius of the black hole as free parameters for a scaling analysis. The transition from full to empty loss-cone is analyzed in our data, and the tidal disruption rate scales with the particle number, N, in the expected way for both cases. For the first time in numerical simulations (under certain conditions) we can support the concept of a critical radius of Frank and Rees, which claims that most stars are tidally accreted on highly eccentric orbits originating from regions far outside the tidal radius. Due to the consumption of stars moving on radial orbits, a velocity anisotropy is found inside the cluster. Finally we estimate the real galactic center based on our simulation results and the scaling analysis.

  4. Three-dimensional stationary cyclic symmetric Einstein-Maxwell solutions; black holes

    SciTech Connect (OSTI)

    Garcia, Alberto A.

    2009-09-15

    From a general metric for stationary cyclic symmetric gravitational fields coupled to Maxwell electromagnetic fields within the (2 + 1)-dimensional gravity the uniqueness of wide families of exact solutions is established. Among them, all uniform electromagnetic solutions possessing electromagnetic fields with vanishing covariant derivatives, all fields having constant electromagnetic invariants F{sub {mu}}{sub {nu}}F{sup {mu}}{sup {nu}} and T{sub {mu}}{sub {nu}}T{sup {mu}}{sup {nu}}, the whole classes of hybrid electromagnetic solutions, and also wide classes of stationary solutions are derived for a third-order nonlinear key equation. Certain of these families can be thought of as black hole solutions. For the most general set of Einstein-Maxwell equations, reducible to three nonlinear equations for the three unknown functions, two new classes of solutions - having anti-de Sitter spinning metric limit - are derived. The relationship of various families with those reported by different authors' solutions has been established. Among the classes of solutions with cosmological constant a relevant place is occupied by the electrostatic and magnetostatic Peldan solutions, the stationary uniform and spinning Clement classes, the constant electromagnetic invariant branches with the particular Kamata-Koikawa solution, the hybrid cyclic symmetric stationary black hole fields, and the non-less important solutions generated via SL(2,R)-transformations where the Clement spinning charged solution, the Martinez-Teitelboim-Zanelli black hole solution, and Dias-Lemos metric merit mention.

  5. Anisotropic in-plane thermal conductivity of black phosphorus nanoribbons at temperatures higher than 100 K

    SciTech Connect (OSTI)

    Lee, Sangwook; Yang, Fan; Suh, Joonki; Yang, Sijie; Lee, Yeonbae; Li, Guo; Sung Choe, Hwan; Suslu, Aslihan; Chen, Yabin; Ko, Changhyun; Park, Joonsuk; Liu, Kai; Li, Jingbo; Hippalgaonkar, Kedar; Urban, Jeffrey J.; Tongay, Sefaattin; Wu, Junqiao

    2015-10-16

    Black phosphorus attracts enormous attention as a promising layered material for electronic, optoelectronic and thermoelectric applications. Here we report large anisotropy in in-plane thermal conductivity of single-crystal black phosphorus nanoribbons along the zigzag and armchair lattice directions at variable temperatures. Thermal conductivity measurements were carried out under the condition of steady-state longitudinal heat flow using suspended-pad micro-devices. We discovered increasing thermal conductivity anisotropy, up to a factor of two, with temperatures above 100 K. A size effect in thermal conductivity was also observed in which thinner nanoribbons show lower thermal conductivity. Analysed with the relaxation time approximation model using phonon dispersions obtained based on density function perturbation theory, the high anisotropy is attributed mainly to direction-dependent phonon dispersion and partially to phonon–phonon scattering. Lastly, our results revealing the intrinsic, orientation-dependent thermal conductivity of black phosphorus are useful for designing devices, as well as understanding fundamental physical properties of layered materials.

  6. Anisotropic in-plane thermal conductivity of black phosphorus nanoribbons at temperatures higher than 100 K

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Lee, Sangwook; Yang, Fan; Suh, Joonki; Yang, Sijie; Lee, Yeonbae; Li, Guo; Sung Choe, Hwan; Suslu, Aslihan; Chen, Yabin; Ko, Changhyun; et al

    2015-10-16

    Black phosphorus attracts enormous attention as a promising layered material for electronic, optoelectronic and thermoelectric applications. Here we report large anisotropy in in-plane thermal conductivity of single-crystal black phosphorus nanoribbons along the zigzag and armchair lattice directions at variable temperatures. Thermal conductivity measurements were carried out under the condition of steady-state longitudinal heat flow using suspended-pad micro-devices. We discovered increasing thermal conductivity anisotropy, up to a factor of two, with temperatures above 100 K. A size effect in thermal conductivity was also observed in which thinner nanoribbons show lower thermal conductivity. Analysed with the relaxation time approximation model using phononmore » dispersions obtained based on density function perturbation theory, the high anisotropy is attributed mainly to direction-dependent phonon dispersion and partially to phonon–phonon scattering. Lastly, our results revealing the intrinsic, orientation-dependent thermal conductivity of black phosphorus are useful for designing devices, as well as understanding fundamental physical properties of layered materials.« less

  7. Breit-Wigner resonances and the quasinormal modes of anti-de Sitter black holes

    SciTech Connect (OSTI)

    Berti, Emanuele; Cardoso, Vitor; Pani, Paolo

    2009-05-15

    We show that the theory of Breit-Wigner resonances can be used as an efficient numerical tool to compute black hole quasinormal modes. For illustration, we focus on the Schwarzschild anti-de Sitter (SAdS) spacetime. The resonance method is better suited to small SAdS black holes than the traditional series expansion method, allowing us to confirm that the damping time scale of small SAdS black holes for scalar and gravitational fields is proportional to r{sub +}{sup -2l-2}, where r{sub +} is the horizon radius. The proportionality coefficients are in good agreement with analytic calculations. We also examine the eikonal limit of SAdS quasinormal modes, confirming quantitatively Festuccia and Liu's [arXiv:0811.1033] prediction of the existence of very long-lived modes. Our results are particularly relevant for the AdS/CFT correspondence, since long-lived modes presumably dominate the decay time scale of the perturbations.

  8. THE BLACK HOLE MASS-GALAXY LUMINOSITY RELATIONSHIP FOR SLOAN DIGITAL SKY SURVEY QUASARS

    SciTech Connect (OSTI)

    Salviander, S.; Shields, G. A.; Bonning, E. W. E-mail: shields@astro.as.utexas.edu

    2015-02-01

    We investigate the relationship between the mass of the central supermassive black hole, M {sub BH}, and the host galaxy luminosity, L {sub gal}, in a sample of quasars from the Sloan Digital Sky Survey Data Release 7. We use composite quasar spectra binned by black hole mass and redshift to assess galaxy features that would otherwise be overwhelmed by noise in individual spectra. The black hole mass is calculated using the photoionization method, and the host galaxy luminosity is inferred from the depth of the Ca II H+K features in the composite spectra. We evaluate the evolution in the M {sub BH}-L {sub gal} relationship by examining the redshift dependence of ? log M {sub BH}, the offset in M {sub BH} from the local M {sub BH}-L {sub gal} relationship. There is little systematic trend in ? log M {sub BH} out to z = 0.8. Using the width of the [O III] emission line as a proxy for the stellar velocity dispersion, ?{sub *}, we find agreement of our derived host luminosities with the locally observed Faber-Jackson relation. This supports the utility of the width of the [O III] line as a proxy for ?{sub *} in statistical studies.

  9. Recovery Act. Sub-Soil Gas and Fluid Inclusion Exploration and Slim Well Drilling, Pumpernickel Valley, Nevada

    SciTech Connect (OSTI)

    Fairbank, Brian D.

    2015-03-27

    Nevada Geothermal Power Company (NGP) was awarded DOE Award DE-EE0002834 in January 2010 to conduct sub-soil gas and fluid inclusion studies and slim well drilling at its Black Warrior Project (now known as North Valley) in Washoe and Churchill Counties, Nevada. The project was designed to apply highly detailed, precise, low-cost subsoil and down-hole gas geochemistry methods from the oil and gas industry to identify upflow zone drilling targets in an undeveloped geothermal prospect. NGP ran into multiple institutional barriers with the Black Warrior project relating to property access and extensive cultural survey requirement. NGP requested that the award be transferred to NGP’s Pumpernickel Valley project, due to the timing delay in obtaining permits, along with additional over-budget costs required. Project planning and permit applications were developed for both the original Black Warrior location and at Pumpernickel. This included obtaining proposals from contractors able to conduct required environmental and cultural surveying, designing the two-meter probe survey methodology and locations, and submitting Notices of Intent and liaising with the Bureau of Land Management to have the two-meter probe work approved. The award had an expiry date of April 30, 2013; however, due to the initial project delays at Black Warrior, and the move of the project from Black Warrior to Pumpernickel, NGP requested that the award deadline be extended. DOE was amenable to this, and worked with NGP to extend the deadline. However, following the loss of the Blue Mountain geothermal power plant in Nevada, NGP’s board of directors changed the company’s mandate to one of cash preservation. NGP was unable to move forward with field work on the Pumpernickel property, or any of its other properties, until additional funding was secured. NGP worked to bring in a project partner to form a joint venture on the property, or to buy the property. This was unsuccessful, and NGP notified

  10. SWIFT OBSERVATIONS OF MAXI J1659-152: A COMPACT BINARY WITH A BLACK HOLE ACCRETOR

    SciTech Connect (OSTI)

    Kennea, J. A.; Romano, P.; Mangano, V.; Beardmore, A. P.; Evans, P. A.; Curran, P. A.; Markwardt, C. B.; Yamaoka, K.

    2011-07-20

    We report on the detection and follow-up high-cadence monitoring observations of MAXI J1659-152, a bright Galactic X-ray binary transient with a likely black hole accretor, by Swift over a 27 day period after its initial outburst detection. MAXI J1659-152 was discovered almost simultaneously by Swift and the Monitor of All-sky X-ray Image on 2010 September 25, and was monitored intensively from the early stages of the outburst through the rise to a brightness of {approx}0.5 Crab by the Swift X-ray, UV/Optical, and the hard X-ray Burst Alert Telescopes. We present temporal and spectral analysis of the Swift observations. The broadband light curves show variability characteristic of black hole candidate transients. We present the evolution of thermal and non-thermal components of the 0.5-150 keV combined X-ray spectra during the outburst. MAXI J1659-152 displays accretion state changes typically associated with black hole binaries, transitioning from its initial detection in the hard state, to the steep power-law state, followed by a slow evolution toward the thermal state, signified by an increasingly dominant thermal component associated with the accretion disk, although this state change did not complete before Swift observations ended. We observe an anti-correlation between the increasing temperature and decreasing radius of the inner edge of the accretion disk, suggesting that the inner edge of the accretion disk infalls toward the black hole as the disk temperature increases. We observed significant evolution in the absorption column during the initial rise of the outburst, with the absorption almost doubling, suggestive of the presence of an evolving wind from the accretion disk. We detect quasi-periodic oscillations that evolve with the outburst, as well as irregular shaped dips that recur with a period of 2.42 {+-} 0.09 hr, strongly suggesting an orbital period that would make MAXI J1659-152 the shortest period black hole binary yet known.

  11. Evolution of porosity and geochemistry in Marcellus Formation black shale during weathering

    SciTech Connect (OSTI)

    Jin, Lixin; Ryan, Mathur; Rother, Gernot; Cole, David; Bazilevskaya, Ekaterina; Williams, Jennifer; Alex, Carone; Brantley, S. L.

    2013-01-01

    Soils developed on the Oatka Creek member of the Marcellus Formation in Huntingdon, Pennsylvania were analyzed to understand the evolution of black shale matrix porosity and the associated changes in elemental and mineralogical composition during infiltration of water into organic-rich shale. Making the reasonable assumption that soil erosion rates are the same as those measured in a nearby location on a less organic-rich shale, we suggest that soil production rates have on average been faster for this black shale compared to the gray shale in similar climate settings. This difference is attributed to differences in composition: both shales are dominantly quartz, illite, and chlorite, but the Oatka Creek member at this location has more organic matter (1.25 wt.% organic carbon in rock fragments recovered from the bottom of the auger cores and nearby outcrops) and accessory pyrite. During weathering, the extremely low-porosity bedrock slowly disaggregates into shale chips with intergranular pores and fractures. Some of these pores are eitherfilled with organic matter or air-filled but remain unconnected, and thus inaccessible to water. Based on weathering bedrock/soil profiles, disintegration is initiated with oxidation of pyrite and organic matter, which increases the overall porosity and most importantly allows water penetration. Water infiltration exposes fresh surface area and thus promotes dissolution of plagioclase and clays. As these dissolution reactions proceed, the porosity in the deepest shale chips recovered from the soil decrease from 9 to 7% while kaolinite and Fe oxyhydroxides precipitate. Eventually, near the land surface, mineral precipitation is outcompeted by dissolution or particle loss of illite and chlorite and porosity in shale chips increases to 20%. As imaged by computed tomographic analysis, weathering causes i) greater porosity, ii) greater average length of connected pores, and iii) a more branched pore network compared to the unweathered

  12. Evolution of porosity and geochemistry in Marcellus Formation black shale during weathering

    SciTech Connect (OSTI)

    Jin, Lixin; Mathur, Ryan; Rother, Gernot; Cole, David; Bazilevskaya, Ekaterina; Williams, Jennifer; Carone, Alex; Brantley, Susan L

    2013-01-01

    Soils developed on the Oatka Creek member of the Marcellus Formation in Huntingdon, Pennsylvania were analyzed to understand the evolution of black shale matrix porosity and the associated changes in elemental and mineralogical composition during infiltration of water into organic-rich shale. Making the reasonable assumption that soil erosion rates are the same as those measured in a nearby location on a less organic-rich shale, we suggest that soil production rates have on average been faster for this black shale compared to the gray shale in similar climate settings. This difference is attributed to differences in composition: both shales are dominantly quartz, illite, and chlorite, but the Oatka Creek member at this location has more organic matter (1.25 wt% organic carbon in rock fragments recovered from the bottom of the auger cores and nearby outcrops) and accessory pyrite. During weathering, the extremely low-porosity bedrock slowly disaggregates into shale chips with intergranular pores and fractures. Some of these pores are either filled with organic matter or air-filled but remain unconnected, and thus inaccessible to water. Based on weathering bedrock/soil profiles, disintegration is initiated with oxidation of pyrite and organic matter, which increases the overall porosity and most importantly allows water penetration. Water infiltration exposes fresh surface area and thus promotes dissolution of plagioclase and clays. As these dissolution reactions proceed, the porosity in the deepest shale chips recovered from the soil decrease from 9 to 7 % while kaolinite and Fe oxyhydroxides precipitate. Eventually, near the land surface, mineral precipitation is outcompeted by dissolution or particle loss of illite and chlorite and porosity in shale chips increases to 20%. As imaged by computed tomographic analysis, weathering causes i) greater porosity, ii) greater average length of connected pores, and iii) a more branched pore network compared to the

  13. CREATING A GEOLOGIC PLAY BOOK FOR TRENTON-BLACK RIVER APPALACHIAN BASIN EXPLORATION

    SciTech Connect (OSTI)

    Douglas G. Patchen; Katharine Lee Avary; John M. Bocan; Michael Hohn; John B. Hickman; Paul D. Lake; James A. Drahovzal; Christopher D. Laughrey; Jaime Kostelnik; Taury Smith; Ron Riley; Mark Baranoski

    2005-04-01

    The Trenton-Black River Appalachian Basin Research Consortium has made significant progress toward their goal of producing a geologic play book for the Trenton-Black River gas play. The final product will include a resource assessment model of Trenton-Black River reservoirs; possible fairways within which to concentrate further studies and seismic programs; and a model for the origin of Trenton-Black River hydrothermal dolomite reservoirs. All seismic data available to the consortium have been examined. Synthetic seismograms constructed for specific wells have enabled researchers to correlate the tops of 15 stratigraphic units determined from well logs to seismic profiles in New York, Pennsylvania, Ohio, West Virginia and Kentucky. In addition, three surfaces for the area have been depth converted, gridded and mapped. A 16-layer velocity model has been developed to help constrain time-to-depth conversions. Considerable progress was made in fault trend delineation and seismic-stratigraphic correlation within the project area. Isopach maps and a network of gamma-ray cross sections supplemented with core descriptions allowed researchers to more clearly define the architecture of the basin during Middle and Late Ordovician time, the control of basin architecture on carbonate and shale deposition and eventually, the location of reservoirs in Trenton Limestone and Black River Group carbonates. The basin architecture itself may be structurally controlled, and this fault-related structural control along platform margins influenced the formation of hydrothermal dolomite reservoirs in original limestone facies deposited in high energy environments. This resulted in productive trends along the northwest margin of the Trenton platform in Ohio. The continuation of this platform margin into New York should provide further areas with good exploration potential. The focus of the petrographic study shifted from cataloging a broad spectrum of carbonate rocks that occur in the

  14. Sowing the seeds of massive black holes in small galaxies: Young clusters as the building blocks of ultracompact dwarf galaxies

    SciTech Connect (OSTI)

    Amaro-Seoane, Pau; Konstantinidis, Symeon; Freitag, Marc Dewi; Coleman Miller, M.; Rasio, Frederic A. E-mail: simos@ari.uni-heidelberg.de E-mail: miller@astro.umd.edu

    2014-02-20

    Interacting galaxies often have complexes of hundreds of young stellar clusters of individual masses ∼10{sup 4}-10{sup 6} M {sub ☉} in regions that are a few hundred parsecs across. These cluster complexes interact dynamically, and their coalescence is a candidate for the origin of some ultracompact dwarf galaxies. Individual clusters with short relaxation times are candidates for the production of intermediate-mass black holes of a few hundred solar masses, via runaway stellar collisions prior to the first supernovae in a cluster. It is therefore possible that a cluster complex hosts multiple intermediate-mass black holes that may be ejected from their individual clusters due to mergers or binary processes, but bound to the complex as a whole. Here we explore the dynamical interaction between initially free-flying massive black holes and clusters in an evolving cluster complex. We find that, after hitting some clusters, it is plausible that the massive black hole will be captured in an ultracompact dwarf forming near the center of the complex. In the process, the hole typically triggers electromagnetic flares via stellar disruptions, and is also likely to be a prominent source of gravitational radiation for the advanced ground-based detectors LIGO and VIRGO. We also discuss other implications of this scenario, notably that the central black hole could be considerably larger than expected in other formation scenarios for ultracompact dwarfs.

  15. THE FAINT 'HEARTBEATS' OF IGR J17091-3624: AN EXCEPTIONAL BLACK HOLE CANDIDATE

    SciTech Connect (OSTI)

    Altamirano, D.; Van der Klis, M.; Wijnands, R.; Kalamkar, M.; Belloni, T.; Stiele, H.; Motta, S.; Munoz-Darias, T.; Linares, M.; Curran, P. A.; Krimm, H.

    2011-12-15

    We report on the first 180 days of Rossi X-Ray Timing Explorer observations of the outburst of the black hole candidate IGR J17091-3624. This source exhibits a broad variety of complex light curve patterns including periods of strong flares alternating with quiet intervals. Similar patterns in the X-ray light curves have been seen in the (up to now) unique black hole system GRS 1915+105. In the context of the variability classes defined by Belloni et al. for GRS 1915+105, we find that IGR J17091-3624 shows the {nu}, {rho}, {alpha}, {lambda}, {beta}, and {mu} classes as well as quiet periods which resemble the {chi} class, all occurring at 2-60 keV count rate levels which can be 10-50 times lower than observed in GRS 1915+105. The so-called {rho} class 'heartbeats' occur as fast as every few seconds and as slow as {approx}100 s, tracing a loop in the hardness-intensity diagram which resembles that previously seen in GRS 1915+105. However, while GRS 1915+105 traverses this loop clockwise, IGR J17091-3624 does so in the opposite sense. We briefly discuss our findings in the context of the models proposed for GRS 1915+105 and find that either all models requiring near Eddington luminosities for GRS 1915+105-like variability fail, or IGR J17091-3624 lies at a distance well in excess of 20 kpc, or it harbors one of the least massive black holes known (<3 M{sub Sun }).

  16. INTERACTION OF RECOILING SUPERMASSIVE BLACK HOLES WITH STARS IN GALACTIC NUCLEI

    SciTech Connect (OSTI)

    Li Shuo; Liu, F. K.; Berczik, Peter; Spurzem, Rainer; Chen Xian E-mail: fkliu@bac.pku.edu.cn

    2012-03-20

    Supermassive black hole binaries (SMBHBs) are the products of frequent galaxy mergers. The coalescence of the SMBHBs is a distinct source of gravitational wave (GW) radiation. The detections of the strong GW radiation and their possible electromagnetic counterparts are essential. Numerical relativity suggests that the post-merger supermassive black hole (SMBH) gets a kick velocity up to 4000 km s{sup -1} due to the anisotropic GW radiations. Here, we investigate the dynamical coevolution and interaction of the recoiling SMBHs and their galactic stellar environments with one million direct N-body simulations including the stellar tidal disruption by the recoiling SMBHs. Our results show that the accretion of disrupted stars does not significantly affect the SMBH dynamical evolution. We investigate the stellar tidal disruption rates as a function of the dynamical evolution of oscillating SMBHs in the galactic nuclei. Our simulations show that most stellar tidal disruptions are contributed by the unbound stars and occur when the oscillating SMBHs pass through the galactic center. The averaged disruption rate is {approx}10{sup -6} M{sub Sun} yr{sup -1}, which is about an order of magnitude lower than that by a stationary SMBH at similar galactic nuclei. Our results also show that a bound star cluster is around the oscillating SMBH of about {approx}0.7% the black hole mass. In addition, we discover a massive cloud of unbound stars following the oscillating SMBH. We also investigate the dependence of the results on the SMBH masses and density slopes of the galactic nuclei.

  17. Formation resistivity as an indicator of oil generation in black shales

    SciTech Connect (OSTI)

    Hester, T.C.; Schmoker, J.W.

    1987-08-01

    Black, organic-rich shales of Late Devonian-Early Mississippi age are present in many basins of the North American craton and, where mature, have significant economic importance as hydrocarbon source rocks. Examples drawn from the upper and lower shale members of the Bakken Formation, Williston basin, North Dakota, and the Woodford Shale, Anadarko basin, Oklahoma, demonstrate the utility of formation resistivity as a direct in-situ indicator of oil generation in black shales. With the onset of oil generation, nonconductive hydrocarbons begin to replace conductive pore water, and the resistivity of a given black-shale interval increases from low levels associated with thermal immaturity to values approaching infinity. Crossplots of a thermal-maturity index (R/sub 0/ or TTI) versus formation resistivity define two populations representing immature shales and shales that have generated oil. A resistivity of 35 ohm-m marks the boundary between immature and mature source rocks for each of the three shales studied. Thermal maturity-resistivity crossplots make possible a straightforward determination of thermal maturity at the onset of oil generation, and are sufficiently precise to detect subtle differences in source-rock properties. For example, the threshold of oil generation in the upper Bakken shale occurs at R/sub 0/ = 0.43-0.45% (TTI = 10-12). The threshold increases to R/sub 0/ = 0.48-0.51% (TTI = 20-26) in the lower Bakken shale, and to R/sub 0/ = 0.56-0.57% (TTI = 33-48) in the most resistive Woodford interval.

  18. Environmental planning as a tool for economic development: The black brook watershed experience

    SciTech Connect (OSTI)

    Ryner, P.C.; Heller, G.B.

    1995-12-01

    The Keene, New Hampshire Planning Department has attempted to use environmental planning as a tool to facilitate industrial development of the Black Brook Watershed. The City has established detailed modeling of drainage, floodplains and groundwater, and has placed that information on accurate computer-based maps. When provided to developers at the beginning of the development process, this environmental information expidites design and permitting while also improving the likelihood of protecting sensitive environmental areas. Starting in 1987 as part of a Master Plan revision process, the Planning Department decided to concentrate on the Black Brook Watershed in northwestern Keene as a target area for a new approach to economic development and environmental protection. The entire watershed was chosen as the boundary for this study area and detailed studies were conducted. During this effort the City formulated a new Economic Development Master Plan which called for the creation of approximately 300 acres of new industrial development within the next ten years. The Black Brook basin was identified as the preferred site. Because of pro-active environmental planning, the City is now able to work in active, cooperative partnership with the private sector in the development of this area. It is clear from this first specific development project that the project development and permitting process will be shortened by at least 60 days, and a minimum of $5,000 to $10,000 in preliminary site information costs will be saved. The availability of good information on wetlands and floodplains has already had a dramatic impact upon proposed site design and has achieved the desired objective of avoiding these sensitive areas whenever possible. The City is now working on the design of an Industrial Design and Permitting System which will be applied to the entire City, based upon what has been learned from this effort.

  19. PIT 9: From "Black Eye" to Part of DOE Cleanup Success

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    PIT 9: From "Black Eye" to Part of DOE Cleanup Success There was a time back in the late 1990s and early 2000s when the words "Pit 9" were synonymous with failure. Failure on the part of a large company to execute its contract to clean up Pit 9. Failure on the part of the Federal government to meet the deadlines to clean up nuclear waste. And failure of a new approach to government contracting - "privatization" - that was supposed to make contractors more

  20. An ethanolic extract of black cohosh causes hematological changes but not estrogenic effects in female rodents

    SciTech Connect (OSTI)

    Mercado-Feliciano, Minerva; Cora, Michelle C.; Witt, Kristine L.; Granville, Courtney A.; Hejtmancik, Milton R.; Fomby, Laurene; Knostman, Katherine A.; Ryan, Michael J.; Newbold, Retha; Smith, Cynthia; Foster, Paul M.; Vallant, Molly K.; Stout, Matthew D.

    2012-09-01

    Black cohosh rhizome (Actaea racemosa) is used as a remedy for pain and gynecological ailments; modern preparations are commonly sold as ethanolic extracts available as dietary supplements. Black cohosh was nominated to the National Toxicology Program (NTP) for toxicity testing due to its widespread use and lack of safety data. Several commercially available black cohosh extracts (BCE) were characterized by the NTP, and one with chemical composition closest to formulations available to consumers was used for all studies. Female B6C3F1/N mice and Wistar Han rats were given 0, 15 (rats only), 62.5 (mice only), 125, 250, 500, or 1000 mg/kg/day BCE by gavage for 90 days starting at weaning. BCE induced dose-dependent hematological changes consistent with a non-regenerative macrocytic anemia and increased frequencies of peripheral micronucleated red blood cells (RBC) in both species. Effects were more severe in mice, which had decreased RBC counts in all treatment groups and increased micronucleated RBC at doses above 125 mg/kg. Dose-dependent thymus and liver toxicity was observed in rats but not mice. No biologically significant effects were observed in other organs. Puberty was delayed 2.9 days at the highest treatment dose in rats; a similar magnitude delay in mice occurred in the 125 and 250 mg/kg groups but not at the higher doses. An additional uterotrophic assay conducted in mice exposed for 3 days to 0.001, 0.01, 0.1, 1, 10, 100 and 500 mg/kg found no estrogenic or anti-estrogenic activity. These are the first studies to observe adverse effects of BCE in rodents. -- Highlights: ? Mice and rats were dosed with black cohosh extract for 90 days starting at weaning. ? Hematological changes were consistent with a non-regenerative macrocytic anemia. ? Peripheral micronucleated red blood cell frequencies increased. ? Puberty was delayed 2.9 days in rats. ? No estrogenic/anti-estrogenic activity was seen in the uterotrophic assay.

  1. UNLEASHING POSITIVE FEEDBACK: LINKING THE RATES OF STAR FORMATION, SUPERMASSIVE BLACK HOLE ACCRETION, AND OUTFLOWS IN DISTANT GALAXIES

    SciTech Connect (OSTI)

    Silk, Joseph

    2013-08-01

    Pressure-regulated star formation is a simple variant on the usual supernova-regulated star formation efficiency that controls the global star formation rate as a function of cold gas content in star-forming galaxies, and accounts for the Schmidt-Kennicutt law in both nearby and distant galaxies. Inclusion of active galactic nucleus (AGN) induced pressure, by jets and/or winds that flow back onto a gas-rich disk, can lead, under some circumstances, to significantly enhanced star formation rates, especially at high redshift and most likely followed by the more widely accepted phase of star formation quenching. Simple expressions are derived that relate supermassive black hole growth, star formation, and outflow rates. The ratios of black hole to spheroid mass and of both black hole accretion and outflow rates to star formation rate are predicted as a function of time. I suggest various tests of the AGN-triggered star formation hypothesis.

  2. ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

    SciTech Connect (OSTI)

    Brandon C. Nuttall

    2003-02-11

    Proposed carbon management technologies include geologic sequestration of CO{sub 2}. A possible, but untested, strategy is to inject CO{sub 2} into organic-rich shales of Devonian age. Devonian black shales underlie approximately two-thirds of Kentucky and are generally thicker and deeper in the Illinois and Appalachian Basin portions of Kentucky. The Devonian black shales serve as both the source and trap for large quantities of natural gas; total gas in place for the shales in Kentucky is estimated to be between 63 and 112 trillion cubic feet. Most of this natural gas is adsorbed on clay and kerogen surfaces, analogous to the way methane is stored in coal beds. In coals, it has been demonstrated that CO{sub 2} is preferentially adsorbed, displacing methane at a ratio of two to one. Black shales may similarly desorb methane in the presence of CO{sub 2}. If black shales similarly desorb methane in the presence of CO{sub 2}, the shales may be an excellent sink for CO{sub 2} with the added benefit of serving to enhance natural gas production. The concept that black, organic-rich Devonian shales could serve as a significant geologic sink for CO{sub 2} is the subject this research. To accomplish this investigation, drill cuttings and cores will be selected from the Kentucky Geological Survey Well Sample and Core Library. CO{sub 2} adsorption analyses will be performed in order to determine the gas-storage potential of the shale and to identify shale facies with the most sequestration potential. In addition, new drill cuttings and sidewall core samples will be acquired to investigate specific black-shale facies, their uptake of CO{sub 2}, and the resultant displacement of methane. Advanced logging techniques (elemental capture spectroscopy) will be used to investigate possible correlations between adsorption capacity and geophysical log measurements.

  3. ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

    SciTech Connect (OSTI)

    Brandon C. Nuttall

    2003-04-28

    Proposed carbon management technologies include geologic sequestration of CO{sub 2}. A possible, but untested, strategy is to inject CO{sub 2} into organic-rich shales of Devonian age. Devonian black shales underlie approximately two-thirds of Kentucky and are generally thicker and deeper in the Illinois and Appalachian Basin portions of Kentucky. The Devonian black shales serve as both the source and trap for large quantities of natural gas; total gas in place for the shales in Kentucky is estimated to be between 63 and 112 trillion cubic feet. Most of this natural gas is adsorbed on clay and kerogen surfaces, analogous to the way methane is stored in coal beds. In coals, it has been demonstrated that CO{sub 2} is preferentially adsorbed, displacing methane at a ratio of two to one. Black shales may similarly desorb methane in the presence of CO{sub 2}. If black shales similarly desorb methane in the presence of CO{sub 2}, the shales may be an excellent sink for CO{sub 2} with the added benefit of serving to enhance natural gas production. The concept that black, organic-rich Devonian shales could serve as a significant geologic sink for CO{sub 2} is the subject this research. To accomplish this investigation, drill cuttings and cores will be selected from the Kentucky Geological Survey Well Sample and Core Library. CO{sub 2} adsorption analyses will be performed in order to determine the gas-storage potential of the shale and to identify shale facies with the most sequestration potential. In addition, new drill cuttings and sidewall core samples will be acquired to investigate specific black-shale facies, their uptake of CO{sub 2}, and the resultant displacement of methane. Advanced logging techniques (elemental capture spectroscopy) will be used to investigate possible correlations between adsorption capacity and geophysical log measurements.

  4. ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

    SciTech Connect (OSTI)

    Brandon C. Nuttall

    2003-02-10

    Proposed carbon management technologies include geologic sequestration of CO{sub 2}. A possible, but untested, strategy is to inject CO{sub 2} into organic-rich shales of Devonian age. Devonian black shales underlie approximately two-thirds of Kentucky and are generally thicker and deeper in the Illinois and Appalachian Basin portions of Kentucky. The Devonian black shales serve as both the source and trap for large quantities of natural gas; total gas in place for the shales in Kentucky is estimated to be between 63 and 112 trillion cubic feet. Most of this natural gas is adsorbed on clay and kerogen surfaces, analogous to the way methane is stored in coal beds. In coals, it has been demonstrated that CO{sub 2} is preferentially adsorbed, displacing methane at a ratio of two to one. Black shales may similarly desorb methane in the presence of CO{sub 2}. If black shales similarly desorb methane in the presence of CO{sub 2}, the shales may be an excellent sink for CO{sub 2} with the added benefit of serving to enhance natural gas production. The concept that black, organic-rich Devonian shales could serve as a significant geologic sink for CO{sub 2} is the subject this research. To accomplish this investigation, drill cuttings and cores will be selected from the Kentucky Geological Survey Well Sample and Core Library. CO{sub 2} adsorption analyses will be performed in order to determine the gas-storage potential of the shale and to identify shale facies with the most sequestration potential. In addition, new drill cuttings and sidewall core samples will be acquired to investigate specific black-shale facies, their uptake of CO{sub 2}, and the resultant displacement of methane. Advanced logging techniques (elemental capture spectroscopy) will be used to investigate possible correlations between adsorption capacity and geophysical log measurements.

  5. A parallax distance to the microquasar GRS 1915+105 and a revised estimate of its black hole mass

    SciTech Connect (OSTI)

    Reid, M. J.; McClintock, J. E.; Steiner, J. F.; Narayan, R.; Steeghs, D.; Remillard, R. A.; Dhawan, V.

    2014-11-20

    Using the Very Long Baseline Array, we have measured a trigonometric parallax for the microquasar GRS 1915+105, which contains a black hole and a K-giant companion. This yields a direct distance estimate of 8.6{sub ?1.6}{sup +2.0} kpc and a revised estimate for the mass of the black hole of 12.4{sub ?1.8}{sup +2.0} M {sub ?}. GRS 1915+105 is at about the same distance as some H II regions and water masers associated with high-mass star formation in the Sagittarius spiral arm of the Galaxy. The absolute proper motion of GRS 1915+105 is 3.19 0.03 mas yr{sup 1} and 6.24 0.05 mas yr{sup 1} toward the east and north, respectively, which corresponds to a modest peculiar speed of 22 24 km s{sup 1} at the parallax distance, suggesting that the binary did not receive a large velocity kick when the black hole formed. On one observational epoch, GRS 1915+105 displayed superluminal motion along the direction of its approaching jet. Considering previous observations of jet motions, the jet in GRS 1915+105 can be modeled with a jet inclination to the line of sight of 60 5 and a variable flow speed between 0.65c and 0.81c, which possibly indicates deceleration of the jet at distances from the black hole ? 2000 AU. Finally, using our measurements of distance and estimates of black hole mass and inclination, we provisionally confirm our earlier result that the black hole is spinning very rapidly.

  6. UPDATED MASS SCALING RELATIONS FOR NUCLEAR STAR CLUSTERS AND A COMPARISON TO SUPERMASSIVE BLACK HOLES

    SciTech Connect (OSTI)

    Scott, Nicholas; Graham, Alister W.

    2013-02-15

    We investigate whether or not nuclear star clusters and supermassive black holes (SMBHs) follow a common set of mass scaling relations with their host galaxy's properties, and hence can be considered to form a single class of central massive object (CMO). We have compiled a large sample of galaxies with measured nuclear star cluster masses and host galaxy properties from the literature and fit log-linear scaling relations. We find that nuclear star cluster mass, M {sub NC}, correlates most tightly with the host galaxy's velocity dispersion: log M {sub NC} = (2.11 {+-} 0.31)log ({sigma}/54) + (6.63 {+-} 0.09), but has a slope dramatically shallower than the relation defined by SMBHs. We find that the nuclear star cluster mass relations involving host galaxy (and spheroid) luminosity and stellar and dynamical mass, intercept with but are in general shallower than the corresponding black hole scaling relations. In particular, M {sub NC}{proportional_to}M {sup 0.55{+-}0.15} {sub Gal,dyn}; the nuclear cluster mass is not a constant fraction of its host galaxy or spheroid mass. We conclude that nuclear stellar clusters and SMBHs do not form a single family of CMOs.

  7. X-RAY CONSTRAINTS ON THE LOCAL SUPERMASSIVE BLACK HOLE OCCUPATION FRACTION

    SciTech Connect (OSTI)

    Miller, Brendan P.; Gallo, Elena; Baldassare, Vivienne; Greene, Jenny E.; Kelly, Brandon C.; Treu, Tommaso; Woo, Jong-Hak

    2015-01-20

    Distinct seed formation mechanisms are imprinted upon the fraction of dwarf galaxies currently containing a central supermassive black hole. Seeding by Population III remnants is expected to produce a higher occupation fraction than is generated with direct gas collapse precursors. Chandra observations of nearby early-type galaxies can directly detect even low-level supermassive black hole activity, and the active fraction immediately provides a firm lower limit to the occupation fraction. Here, we use the volume-limited AMUSE surveys of ?200 optically selected early-type galaxies to characterize simultaneously, for the first time, the occupation fraction and the scaling of L {sub X} with M {sub star}, accounting for intrinsic scatter, measurement uncertainties, and X-ray limits. For early-type galaxies with M {sub star} < 10{sup 10} M {sub ?}, we obtain a lower limit to the occupation fraction of >20% (at 95% confidence), but full occupation cannot be excluded. The preferred dependence of log L {sub X} upon log M {sub star} has a slope of ?0.7-0.8, consistent with the ''downsizing'' trend previously identified from the AMUSE data set, and a uniform Eddington efficiency is disfavored at ?2?. We provide guidelines for the future precision with which these parameters may be refined with larger or more sensitive samples.

  8. Quantum compositeness of gravity: black holes, AdS and inflation

    SciTech Connect (OSTI)

    Dvali, Gia; Gomez, Cesar E-mail: cesar.gomez@uam.es

    2014-01-01

    Gravitational backgrounds, such as black holes, AdS, de Sitter and inflationary universes, should be viewed as composite of N soft constituent gravitons. It then follows that such systems are close to quantum criticality of graviton Bose-gas to Bose-liquid transition. Generic properties of the ordinary metric description, including geodesic motion or particle-creation in the background metric, emerge as the large-N limit of quantum scattering of constituent longitudinal gravitons. We show that this picture correctly accounts for physics of large and small black holes in AdS, as well as reproduces well-known inflationary predictions for cosmological parameters. However, it anticipates new effects not captured by the standard semi-classical treatment. In particular, we predict observable corrections that are sensitive to the inflationary history way beyond last 60 e-foldings. We derive an absolute upper bound on the number of e-foldings, beyond which neither de Sitter nor inflationary Universe can be approximated by a semi-classical metric. However, they could in principle persist in a new type of quantum eternity state. We discuss implications of this phenomenon for the cosmological constant problem.

  9. Investigation of Pressurized Entrained-Flow Kraft Black Liquor Gasification in an Industrially Relevant Environment

    SciTech Connect (OSTI)

    Kevin Whitty

    2008-06-30

    The University of Utah's project 'Investigation of Pressurized Entrained-Flow Kraft Black Liquor Gasification in an Industrially Relevant Environment' (U.S. DOE Cooperative Agreement DE-FC26-04NT42261) was a response to U.S. DOE/NETL solicitation DE-PS36-04GO94002, 'Biomass Research and Development Initiative' Topical Area 4-Kraft Black Liquor Gasification. The project began September 30, 2004. The objective of the project was to improve the understanding of black liquor conversion in high pressure, high temperature reactors that gasify liquor through partial oxidation with either air or oxygen. The physical and chemical characteristics of both the gas and condensed phase were to be studied over the entire range of liquor conversion, and the rates and mechanisms of processes responsible for converting the liquor to its final smelt and syngas products were to be investigated. This would be accomplished by combining fundamental, lab-scale experiments with measurements taken using a new semi-pilot scale pressurized entrained-flow gasifier. As a result of insufficient availability of funds and changes in priority within the Office of Biomass Programs of the U.S. Department of Energy, the research program was terminated in its second year. In total, only half of the budgeted funding was made available for the program, and most of this was used during the first year for construction of the experimental systems to be used in the program. This had a severe impact on the program. As a consequence, most of the planned research was unable to be performed. Only studies that relied on computational modeling or existing experimental facilities started early enough to deliver useful results by the time to program was terminated Over the course of the program, small scale (approx. 1 ton/day) entrained-flow gasifier was designed and installed at the University of Utah's off-campus Industrial Combustion and Gasification Research Facility. The system is designed to operate at

  10. Self-similar cosmological solutions with dark energy. II. Black holes, naked singularities, and wormholes

    SciTech Connect (OSTI)

    Maeda, Hideki; Harada, Tomohiro; Carr, B. J.

    2008-01-15

    We use a combination of numerical and analytical methods, exploiting the equations derived in a preceding paper, to classify all spherically symmetric self-similar solutions which are asymptotically Friedmann at large distances and contain a perfect fluid with equation of state p=({gamma}-1){mu} with 0<{gamma}<2/3. The expansion of the Friedmann universe is accelerated in this case. We find a one-parameter family of self-similar solutions representing a black hole embedded in a Friedmann background. This suggests that, in contrast to the positive pressure case, black holes in a universe with dark energy can grow as fast as the Hubble horizon if they are not too large. There are also self-similar solutions which contain a central naked singularity with negative mass and solutions which represent a Friedmann universe connected to either another Friedmann universe or some other cosmological model. The latter are interpreted as self-similar cosmological white hole or wormhole solutions. The throats of these wormholes are defined as two-dimensional spheres with minimal area on a spacelike hypersurface and they are all nontraversable because of the absence of a past null infinity.

  11. Quantum compositeness of gravity: black holes, AdS and inflation

    SciTech Connect (OSTI)

    Dvali, Gia; Gomez, Cesar

    2014-01-14

    Gravitational backgrounds, such as black holes, AdS, de Sitter and inflationary universes, should be viewed as composite of N soft constituent gravitons. It then follows that such systems are close to quantum criticality of graviton Bose-gas to Bose-liquid transition. Generic properties of the ordinary metric description, including geodesic motion or particle-creation in the background metric, emerge as the large-N limit of quantum scattering of constituent longitudinal gravitons. We show that this picture correctly accounts for physics of large and small black holes in AdS, as well as reproduces well-known inflationary predictions for cosmological parameters. However, it anticipates new effects not captured by the standard semi-classical treatment. In particular, we predict observable corrections that are sensitive to the inflationary history way beyond last 60 e-foldings. We derive an absolute upper bound on the number of e-foldings, beyond which neither de Sitter nor inflationary Universe can be approximated by a semi-classical metric. However, they could in principle persist in a new type of quantum eternity state. We discuss implications of this phenomenon for the cosmological constant problem.

  12. THE MISSING GOLIATH'S SLINGSHOT: MASSIVE BLACK HOLE RECOIL AT M83

    SciTech Connect (OSTI)

    Dottori, Horacio; Diaz, Ruben J.; Facundo Albacete-Colombo, Juan

    2010-07-01

    The Fanaroff-Riley II radio source J133658.3-295105, which is also an X-ray source, appears to be projected onto the disk of the barred-spiral galaxy M83 at about 60'' from the galaxy's optical nucleus. J133658.3-295105 and its radio lobes are aligned with the optical nucleus of M 83 and two other radio sources, neither of which are supernova remnants or H II regions. Due to this peculiar on-the-sky projection, J133658.3-295105 was previously studied by Gemini+GMOS optical spectroscopy, which marginally revealed the presence of H{alpha} in emission receding at 130 km s{sup -1} with respect to the optical nucleus. In this Letter, we reanalyze the Chandra spectroscopy carried out in 2000. We show that J133658.3-295105 presents an Fe K{alpha} emission line at a redshift of z = 0.018. This redshift is compatible with a black hole at the distance of M 83. We discuss similarities to the recently reported micro-quasar in NGC 5408. This finding reinforces the kicked-off black hole scenario for J133658.3-295105.

  13. Bulk scalar emission from a rotating black hole pierced by a tense brane

    SciTech Connect (OSTI)

    Kobayashi, Tsutomu; Nozawa, Masato; Takamizu, Yu-ichi

    2008-02-15

    We study the emission of scalar fields into the bulk from a six-dimensional rotating black hole pierced by a 3-brane. We determine the angular eigenvalues in the presence of finite brane tension by using the continued fraction method. The radial equation is integrated numerically, giving the absorption probability (graybody factor) in a wider frequency range than in the preexisting literature. We then compute the power and angular momentum emission spectra for different values of the rotation parameter and brane tension, and compare their relative behavior in detail. As is expected from the earlier result for a nonrotating black hole, the finite brane tension suppresses the emission rates. As the rotation parameter increases, the power spectra are reduced at low frequencies due to the smaller Hawking temperature and are enhanced at high frequencies due to superradiance. The angular momentum spectra are enhanced over the whole frequency range as the rotation parameter increases. The spectra and the amounts of energy and angular momentum radiated away into the bulk are thus determined by the interplay of these effects.

  14. A PRECISION TEST FOR AN EXTRA SPATIAL DIMENSION USING BLACK-HOLE-PULSAR BINARIES

    SciTech Connect (OSTI)

    Simonetti, John H.; Minic, Djordje; Surani, Umair; Vijayan, Vipin; Kavic, Michael

    2011-08-20

    We discuss the observable effects of enhanced black hole mass loss in a black hole-neutron star (BH-NS) binary, due to the presence of a warped extra spatial dimension of curvature radius L in the braneworld scenario. For some masses and orbital parameters in the expected ranges the binary components would outspiral-the opposite of the behavior due to energy loss from gravitational radiation alone. If the NS is a pulsar, observations of the rate of change of the orbital period with a precision obtained for the binary pulsar B1913+16 could easily detect the effect of mass loss. For M{sub BH} = 7 M{sub sun}, M{sub NS} = 1.4 M{sub sun}, eccentricity e = 0.1, and L = 10 {mu}m, the critical orbital period dividing systems that inspiral from systems that outspiral is P {approx} 6.5 hr, which is within the range of expected orbital periods; this value drops to P {approx} 4.2 hr for M{sub BH} = 5 M{sub sun}. Observations of a BH-pulsar system could set considerably better limits on L in these braneworld models than could be determined by torsion-balance gravity experiments in the foreseeable future.

  15. TEM Observations of Corrosion Behaviors of Platinized Carbon Blacks under Thermal and Electrochemical Conditions

    SciTech Connect (OSTI)

    Liu, Z.Y.; Zhang, J.L.; Yu, P.T.; Zhang, J.X.; Makharia, R.; More, Karren Leslie; Stach, Eric

    2010-01-01

    Carbon blacks such as Vulcan XC-72 are widely used to support platinum (Pt) or Pt alloy catalysts in proton exchange membrane fuel cells. Despite their widespread use, carbon blacks are susceptible to corrosion during fuel cell operations. In this work, the corrosion behaviors of platinized Vulcan XC-72 nanoparticles under thermal and electrochemical conditions were monitored by transmission electron microscopy (TEM). The thermal corrosion experiment was carried out in a gas-cell TEM, which allows for a direct observation of the thermal oxidation behavior of the nanoparticles. The electrochemical corrosion experiment was performed outside of the TEM by loading the nanoparticles on a TEM grid and then electrochemically corroding them step by step followed by taking TEM images from exactly the same nanoparticles after each step. This work revealed four types of structural changes: (i) total removal of structurally weak aggregates, (ii) breakdown of aggregates via neck-breaking, (iii) center-hollowed primary particles caused by an inside-out corrosion starting from the center to outer region, and (iv) gradual decrease in the size of primary particles caused by a uniform removal of material from the surface. These structural changes took place in sequence or simultaneously depending on the competition of carbon corrosion dynamical processes. The results obtained from this work provide insight on carbon corrosion and its effects on fuel cells' long-term performance and durability.

  16. Milagro limits and HAWC sensitivity for the rate-density of evaporating primordial black holes

    SciTech Connect (OSTI)

    Abdo, A. A.; Abeysekara, A. U.; Alfaro, R.; Allen, B. T.; Alvarez, C.; Alvarez, J. D.; Arceo, R.; Arteaga-Velazquez, J. C.; Aune, T.; H. A. Ayala Solares; Barber, A. S.; Baughman, B. M.; Bautista-Elivar, N.; Gonzalez, J. Becerra; Belmont, E.; BenZvi, S. Y.; Berley, D.; Bonilla Rosales, M.; Braun, J.; Caballero-Lopez, R. A.; Caballero-Mora, K. S.; Carraminana, A.; Castillo, M.; Christopher, G. E.; Cotti, U.; Cotzomi, J.; de la Fuente, E.; De León, C.; DeYoung, T.; Diaz Hernandez, R.; Diaz-Cruz, L.; Díaz-Vélez, J. C.; Dingus, B. L.; DuVernois, M. A.; Ellsworth, R. W.; Fiorino, D. W.; Fraija, N.; Galindo, A.; Garfias, F.; González, M. M.; Goodman, J. A.; Grabski, V.; Gussert, M.; Hampel-Arias, Z.; Harding, J. P.; Hays, E.; Hoffman, C. M.; Hui, C. M.; Hüntemeyer, P.; Imran, A.; Iriarte, A.; Karn, P.; Kieda, D.; Kolterman, B. E.; Kunde, G. J.; Lara, A.; Lauer, R. J.; Lee, W. H.; Lennarz, D.; Vargas, H. Leon; Linares, E. C.; Linnemann, J. T.; Longo, M.; Luna-GarcIa, R.; MacGibbon, J. H.; Marinelli, A.; Marinelli, S. S.; Martinez, H.; Martinez, O.; Martínez-Castro, J.; J. A.J. Matthews; McEnery, J.; Mendoza Torres, E.; Mincer, A. I.; Miranda-Romagnoli, P.; Moreno, E.; Morgan, T.; Mostafa, M.; Nellen, L.; Nemethy, P.; Newbold, M.; Noriega-Papaqui, R.; Oceguera-Becerra, T.; Patricelli, B.; Pelayo, R.; Perez-Perez, E. G.; Pretz, J.; Riviere, C.; Rosa-Gonzalez, D.; Ruiz-Velasco, E.; Ryan, J.; Salazar, H.; Salesa, F.; Sandoval, A.; Saz Parkinson, P. M.; Schneider, M.; Silich, S.; Sinnis, G.; Smith, A. J.; Stump, D.; Sparks Woodle, K.; Springer, R. W.; Taboada, I.; Toale, P. A.; Tollefson, K.; Torres, I.; Ukwatta, T. N.; Vasileiou, V.; Villasenor, L.; Weisgarber, T.; Westerhoff, S.; Williams, D. A.; Wisher, I. G.; Wood, J.; Yodh, G. B.; Younk, P. W.; Zaborov, D.; Zepeda, A.; Zhou, H.

    2015-04-01

    Primordial Black Holes (PBHs) are gravitationally collapsed objects that may have been created by density fluctuations in the early universe and could have arbitrarily small masses down to the Planck scale. Hawking showed that due to quantum effects, a black hole has a temperature inversely proportional to its mass and will emit all species of fundamental particles thermally. PBHs with initial masses of ~ 5.0 × 10¹⁴ g should be expiring in the present epoch with bursts of high-energy particles, including gamma radiation in the GeV – TeV energy range. The Milagro high energy observatory, which operated from 2000 to 2008, is sensitive to the high end of the PBH evaporation gamma-ray spectrum. Due to its large field-of-view, more than 90% duty cycle and sensitivity up to 100 TeV gamma rays, the Milagro observatory is well suited to perform a search for PBH bursts. Based on a search on the Milagro data, we report new PBH burst rate density upper limits over a range of PBH observation times. In addition, we report the sensitivity of the Milagro successor, the High Altitude Water Cherenkov (HAWC) observatory, to PBH evaporation events.

  17. The MassiveBlack-II simulation: The evolution of haloes and galaxies to z ~ 0

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Khandai, Nishikanta; Di Matteo, Tiziana; Croft, Rupert; Wilkins, Stephen; Feng, Yu; Tucker, Evan; DeGraf, Colin; Liu, Mao -Sheng

    2015-04-24

    We investigate the properties and clustering of halos, galaxies and blackholes to z = 0 in the high resolution hydrodynamical simulation MassiveBlack-II (MBII). MBII evolves a ΛCDM cosmology in a cubical comoving volume Vbox = (100Mpc/h)³. It is the highest resolution simulation of this size which includes a self-consistent model for star formation, black hole accretion and associated feedback. We provide a simulation browser web application which enables interactive search and tagging of the halos, subhalos and their properties and publicly release our galaxy catalogs to the scientific community. Our analysis of the halo mass function in MBII reveals thatmore » baryons have strong effects with changes in the halo abundance of 20–35% below the knee of the mass function (Mhalo 1013.2 M⊙ h at z = 0) when compared to dark-matter-only simulations. We provide a fitting function for the halo MF out to redshift z = 11 and discuss its limitations.« less

  18. Measured Black Carbon Deposition on the Sierra Nevada Snow Pack and Implication for Snow Pack Retreat

    SciTech Connect (OSTI)

    Hadley, O.L.; Corrigan, C.E.; Kirchstetter, T.W.; Cliff, S.S.; Ramanathan, V.

    2010-01-12

    Modeling studies show that the darkening of snow and ice by black carbon deposition is a major factor for the rapid disappearance of arctic sea ice, mountain glaciers and snow packs. This study provides one of the first direct measurements for the efficient removal of black carbon from the atmosphere by snow and its subsequent deposition to the snow packs of California. The early melting of the snow packs in the Sierras is one of the contributing factors to the severe water problems in California. BC concentrations in falling snow were measured at two mountain locations and in rain at a coastal site. All three stations reveal large BC concentrations in precipitation, ranging from 1.7 ng/g to 12.9 ng/g. The BC concentrations in the air after the snow fall were negligible suggesting an extremely efficient removal of BC by snow. The data suggest that below cloud scavenging, rather than ice nuclei, was the dominant source of BC in the snow. A five-year comparison of BC, dust, and total fine aerosol mass concentrations at multiple sites reveals that the measurements made at the sampling sites were representative of large scale deposition in the Sierra Nevada. The relative concentration of iron and calcium in the mountain aerosol indicates that one-quarter to one-third of the BC may have been transported from Asia.

  19. Milagro limits and HAWC sensitivity for the rate-density of evaporating primordial black holes

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Abdo, A. A.; Abeysekara, A. U.; Alfaro, R.; Allen, B. T.; Alvarez, C.; Alvarez, J. D.; Arceo, R.; Arteaga-Velazquez, J. C.; Aune, T.; H. A. Ayala Solares; et al

    2015-04-01

    Primordial Black Holes (PBHs) are gravitationally collapsed objects that may have been created by density fluctuations in the early universe and could have arbitrarily small masses down to the Planck scale. Hawking showed that due to quantum effects, a black hole has a temperature inversely proportional to its mass and will emit all species of fundamental particles thermally. PBHs with initial masses of ~ 5.0 × 10¹⁴ g should be expiring in the present epoch with bursts of high-energy particles, including gamma radiation in the GeV – TeV energy range. The Milagro high energy observatory, which operated from 2000 tomore » 2008, is sensitive to the high end of the PBH evaporation gamma-ray spectrum. Due to its large field-of-view, more than 90% duty cycle and sensitivity up to 100 TeV gamma rays, the Milagro observatory is well suited to perform a search for PBH bursts. Based on a search on the Milagro data, we report new PBH burst rate density upper limits over a range of PBH observation times. In addition, we report the sensitivity of the Milagro successor, the High Altitude Water Cherenkov (HAWC) observatory, to PBH evaporation events.« less

  20. SUPERMASSIVE BLACK HOLE FORMATION AT HIGH REDSHIFTS THROUGH A PRIMORDIAL MAGNETIC FIELD

    SciTech Connect (OSTI)

    Sethi, Shiv; Pandey, Kanhaiya; Haiman, Zoltan E-mail: kanhaiya@rri.res.i

    2010-09-20

    It has been proposed that primordial gas in early dark matter halos, with virial temperatures T{sub vir} {approx}> 10{sup 4} K, can avoid fragmentation and undergo rapid collapse, possibly resulting in a supermassive black hole. This requires the gas to avoid cooling and to remain at temperatures near T {approx} 10{sup 4} K. We show that this condition can be satisfied in the presence of a sufficiently strong primordial magnetic field, which heats the collapsing gas via ambipolar diffusion. If the field has a strength above |B | {approx}>3.6 (comoving) nG, the collapsing gas is kept warm (T {approx} 10{sup 4} K) until it reaches the critical density n{sub crit} {approx} 10{sup 3} cm{sup -3} at which the rotovibrational states of H{sub 2} approach local thermodynamic equilibrium. H{sub 2} cooling then remains inefficient and the gas temperature stays near {approx}10{sup 4} K, even as it continues to collapse at higher densities. The critical magnetic field strength required to permanently suppress H{sub 2} cooling is somewhat higher than the upper limit of {approx}2 nG from the cosmic microwave background. However, it can be realized in the rare {approx}>(2-3){sigma} regions of the spatially fluctuating B field; these regions contain a sufficient number of halos to account for z {approx} 6 quasar black holes.

  1. The MassiveBlack-II simulation: The evolution of haloes and galaxies to z ~ 0

    SciTech Connect (OSTI)

    Khandai, Nishikanta; Di Matteo, Tiziana; Croft, Rupert; Wilkins, Stephen; Feng, Yu; Tucker, Evan; DeGraf, Colin; Liu, Mao -Sheng

    2015-04-24

    We investigate the properties and clustering of halos, galaxies and blackholes to z = 0 in the high resolution hydrodynamical simulation MassiveBlack-II (MBII). MBII evolves a ?CDM cosmology in a cubical comoving volume Vbox = (100Mpc/h). It is the highest resolution simulation of this size which includes a self-consistent model for star formation, black hole accretion and associated feedback. We provide a simulation browser web application which enables interactive search and tagging of the halos, subhalos and their properties and publicly release our galaxy catalogs to the scientific community. Our analysis of the halo mass function in MBII reveals that baryons have strong effects with changes in the halo abundance of 2035% below the knee of the mass function (Mhalo 1013.2 M? h at z = 0) when compared to dark-matter-only simulations. We provide a fitting function for the halo MF out to redshift z = 11 and discuss its limitations.

  2. Black carbon emissions in the United Kingdom during the past four decades: An empirical analysis

    SciTech Connect (OSTI)

    Novakov, T.; Hansen, J.E.

    2004-04-22

    We use data from a unique 40-year record of 150 urban and rural stations in the ''Black Smoke and SO2 Network'' in Great Britain to infer information about sources of atmospheric black carbon (BC). The data show a rapid decline of ambient atmospheric BC between 1962 and the early 1990s that exceeds the decline in official estimates of BC emissions based only on amount of fuel use and mostly fixed emission factors. This provides empirical confirmation of the existence and large impact of a time-dependent ''technology factor'' that must multiply the rate of fossil fuel use. Current ambient BC amounts in Great Britain comparable to those in western and central Europe, with diesel engines being the principal present source. From comparison of BC and SO2 data we infer that current BC emission inventories understate true emissions in the U.K. by about a factor of two. The results imply that there is the potential for improved technology to achieve large reduction of global ambient BC. There is a need for comparable monitoring of BC in other countries.

  3. Quantification of black carbon mixing state from traffic: Implications for aerosol optical properties

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Willis, Megan D.; Healy, Robert M.; Riemer, Nicole; West, Matthew; Wang, Jon M.; Jeong, Cheol -Heon; Wenger, John C.; Evans, Greg J.; Abbatt, Jonathan P. D.; Lee, Alex K. Y.

    2016-04-14

    The climatic impacts of black carbon (BC) aerosol, an important absorber of solar radiation in the atmosphere, remain poorly constrained and are intimately related to its particle-scale physical and chemical properties. Using particle-resolved modelling informed by quantitative measurements from a soot-particle aerosol mass spectrometer, we confirm that the mixing state (the distribution of co-emitted aerosol amongst fresh BC-containing particles) at the time of emission significantly affects BC-aerosol optical properties even after a day of atmospheric processing. Both single particle and ensemble aerosol mass spectrometry observations indicate that BC near the point of emission co-exists with hydrocarbon-like organic aerosol (HOA) inmore » two distinct particle types: HOA-rich and BC-rich particles. The average mass fraction of black carbon in HOA-rich and BC-rich particle classes was  < 0.1 and 0.8, respectively. Notably, approximately 90 % of BC mass resides in BC-rich particles. This new measurement capability provides quantitative insight into the physical and chemical nature of BC-containing particles and is used to drive a particle-resolved aerosol box model. Lastly, significant differences in calculated single scattering albedo (an increase of 0.1) arise from accurate treatment of initial particle mixing state as compared to the assumption of uniform aerosol composition at the point of BC injection into the atmosphere.« less

  4. Soliton and black hole solutions of su(N) Einstein-Yang-Mills theory in anti-de Sitter space

    SciTech Connect (OSTI)

    Baxter, J. E.; Winstanley, Elizabeth; Helbling, Marc

    2007-11-15

    We present new soliton and hairy black hole solutions of su(N) Einstein-Yang-Mills theory in asymptotically anti-de Sitter space. These solutions are described by N+1 independent parameters, and have N-1 gauge field degrees of freedom. We examine the space of solutions in detail for su(3) and su(4) solitons and black holes. If the magnitude of the cosmological constant is sufficiently large, we find solutions where all the gauge field functions have no zeros. These solutions are of particular interest because we anticipate that at least some of them will be linearly stable.

  5. The Use of Tritiated Wastewater from NPP Cernavoda to Estimate Maximum Soluble Pollutants on Danube-Black Sea Channel

    SciTech Connect (OSTI)

    Varlam, Carmen; Stefanescu, Ioan; Patrascub, Vasile; Varlam, Mihai; Raceanu, Mircea; Enache, Adrian; Bucur, Cristina

    2005-07-15

    In this paper we propose to use tritiated liquid effluents from a CANDU type reactor as a tracer, to study hydrodynamics on Danube-Black Sea Channel. Tritiated water can be used to simulate the transport and dispersion of solutes in mentioned Channel, because it has the same physical characteristic as water. Measured tracer response curves produced from controlled evacuations provide an efficient method of obtaining necessary data. This paper presents the establishing of proper mixing length, and the base line of tritium concentration in studied area. These first steps were used to construct the unit-peak attenuation (UPA) curve for a sector of the Danube-Black Sea Channel.

  6. Quantum of area {Delta}A=8{pi}l{sub P}{sup 2} and a statistical interpretation of black hole entropy

    SciTech Connect (OSTI)

    Ropotenko, Kostiantyn

    2010-08-15

    In contrast to alternative values, the quantum of area {Delta}A=8{pi}l{sub P}{sup 2} does not follow from the usual statistical interpretation of black hole entropy; on the contrary, a statistical interpretation follows from it. This interpretation is based on the two concepts: nonadditivity of black hole entropy and Landau quantization. Using nonadditivity a microcanonical distribution for a black hole is found and it is shown that the statistical weight of a black hole should be proportional to its area. By analogy with conventional Landau quantization, it is shown that quantization of a black hole is nothing but the Landau quantization. The Landau levels of a black hole and their degeneracy are found. The degree of degeneracy is equal to the number of ways to distribute a patch of area 8{pi}l{sub P}{sup 2} over the horizon. Taking into account these results, it is argued that the black hole entropy should be of the form S{sub bh}=2{pi}{center_dot}{Delta}{Gamma}, where the number of microstates is {Delta}{Gamma}=A/8{pi}l{sub P}{sup 2}. The nature of the degrees of freedom responsible for black hole entropy is elucidated. The applications of the new interpretation are presented. The effect of noncommuting coordinates is discussed.

  7. Galaxy Formation with Self-Consistently Modeled Stars and Massive Black Holes. I: Feedback-Regulated Star Formation and Black Hole Growth

    SciTech Connect (OSTI)

    Kim, Ji-hoon; Wise, John H.; Alvarez, Marcelo A.; Abel, Tom; /KIPAC, Menlo Park /Stanford U., Phys. Dept.

    2011-11-04

    There is mounting evidence for the coevolution of galaxies and their embedded massive black holes (MBHs) in a hierarchical structure formation paradigm. To tackle the nonlinear processes of galaxy-MBH interaction, we describe a self-consistent numerical framework which incorporates both galaxies and MBHs. The high-resolution adaptive mesh refinement (AMR) code Enzo is modified to model the formation and feedback of molecular clouds at their characteristic scale of 15.2 pc and the accretion of gas onto an MBH. Two major channels of MBH feedback, radiative feedback (X-ray photons followed through full three-dimensional adaptive ray tracing) and mechanical feedback (bipolar jets resolved in high-resolution AMR), are employed. We investigate the coevolution of a 9.2 x 10{sup 11} M {circle_dot} galactic halo and its 10{sup 5} {circle_dot} M embedded MBH at redshift 3 in a cosmological CDM simulation. The MBH feedback heats the surrounding interstellar medium (ISM) up to 10{sup 6} K through photoionization and Compton heating and locally suppresses star formation in the galactic inner core. The feedback considerably changes the stellar distribution there. This new channel of feedback from a slowly growing MBH is particularly interesting because it is only locally dominant and does not require the heating of gas globally on the disk. The MBH also self-regulates its growth by keeping the surrounding ISM hot for an extended period of time.

  8. Chandra spectroscopy of MAXI J1305704: Detection of an infalling black hole disk wind?

    SciTech Connect (OSTI)

    Miller, J. M.; Maitra, D.; Reynolds, M. T.; Degenaar, N.; King, A. L.; Raymond, J.; Kallman, T. R.; Fabian, A. C.; Proga, D.; Reynolds, C. S.; Cackett, E. M.; Kennea, J. A.; Beardmore, A.

    2014-06-10

    We report on a high-resolution Chandra/HETG X-ray spectrum of the transient X-ray binary MAXI J1305704. A rich absorption complex is detected in the Fe L band, including density-sensitive lines from Fe XX, Fe XXI, and Fe XXII. Spectral analysis over three wavelength bands with a large grid of XSTAR photoionization models generally requires a gas density of n ? 10{sup 17} cm{sup 3}. Assuming a luminosity of L = 10{sup 37} erg s{sup 1}, fits to the 10-14 band constrain the absorbing gas to lie within r = (3.9 0.7) 10{sup 3} km from the central engine, or about r = 520 90 (M/5 M {sub ?}) r{sub g} , where r{sub g} = GM/c {sup 2}. At this small distance from the compact object, gas in stable orbits should have a gravitational redshift of z = v/c ? (3 1) 10{sup 3} (M/5 M {sub ?}), and any tenuous inflowing gas should have a free-fall velocity of v/c ? (6 1) 10{sup 2} (M/5 M {sub ?}){sup 1/2}. The best-fit single-zone photoionization models measure a redshift of v/c = (2.6-3.2) 10{sup 3}. Models with two absorbing zones provide significantly improved fits, and the additional zone is measured to have a redshift of v/c = (4.6-4.9) 10{sup 2} (models including two zones suggest slightly different radii and may point to lower densities). Thus, the observed shifts are broadly consistent with those expected at the photoionization radius. The absorption spectrum revealed in MAXI J1305704 may be best explained in terms of a 'failed wind' like those predicted in some recent numerical simulations of black hole accretion flows. The robustness of the velocity shifts was explored through detailed simulations with the Chandra/MARX ray-tracing package and analysis of the zeroth-order ACIS-S3 spectrum. These tests are particularly important given the anomalously large angle between the source and the optical axis in this observation. The simulations and ACIS spectrum suggest that the shifts are not instrumental; however, strong caution is warranted. We discuss

  9. Investigation of refractory black carbon-containing particle morphologies using the single-particle soot photometer (SP2)

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Sedlacek, III, Arthur J.; Lewis, Ernie R.; Onasch, Timothy B.; Lambe, Andrew T.; Davidovits, Paul

    2015-07-24

    An important source of uncertainty in radiative forcing by absorbing aerosol particles is the uncertainty in their morphologies (i.e., the location of the absorbing substance on/in the particles). To examine the effects of particle morphology on the response of an individual black carbon-containing particle in a Single-Particle Soot Photometer (SP2), a series of experiments was conducted to investigate black carbon-containing particles of known morphology using Regal black (RB), a proxy for collapsed soot, as the light-absorbing substance. Particles were formed by coagulation of RB with either a solid substance (sodium chloride or ammonium sulfate) or a liquid substance (dioctyl sebacate),more » and by condensation with dioctyl sebacate, the latter experiment forming particles in a core-shell configuration. Each particle type experienced fragmentation (observed as negative lagtimes), and each yielded similar lagtime responses in some instances, confounding attempts to differentiate particle morphology using current SP2 lagtime analysis. SP2 operating conditions, specifically laser power and sample flow rate, which in turn affect the particle heating and dissipation rates, play an important role in the behavior of particles in the SP2, including probability of fragmentation. This behavior also depended on the morphology of the particles and on the thermo-chemical properties of the non-RB substance. Although these influences cannot currently be unambiguously separated, the SP2 analysis may still provide useful information on particle mixing states and black carbon particle sources.« less

  10. CONSTRAINTS ON THE SPACETIME GEOMETRY AROUND 10 STELLAR-MASS BLACK HOLE CANDIDATES FROM THE DISK'S THERMAL SPECTRUM

    SciTech Connect (OSTI)

    Kong, Lingyao; Li, Zilong; Bambi, Cosimo

    2014-12-20

    In a previous paper, one of us (C. Bambi) described a code to compute the thermal spectrum of geometrically thin and optically thick accretion disks around generic stationary and axisymmetric black holes, which are not necessarily of the Kerr type. As the structure of the accretion disk and the propagation of electromagnetic radiation from the disk to the distant observer depend on the background metric, the analysis of the thermal spectrum of thin disks can be used to test the actual nature of black hole candidates. In this paper, we consider the 10 stellar-mass black hole candidates for which the spin parameter has already been estimated from the analysis of the disk's thermal spectrum under the assumption of the Kerr background, and we translate the measurements reported in the literature into constraints on the spin parameter-deformation parameter plane. The analysis of the disk's thermal spectrum can be used to estimate only one parameter of the geometry close to the compact object; therefore, it is not possible to get independent measurements of both the spin and the deformation parameters. The constraints obtained here will be used in combination with other measurements in future work with the final goal of breaking the degeneracy between the spin and possible deviations from the Kerr solution and thus test the Kerr black hole hypothesis.

  11. Investigation of refractory black carbon-containing particle morphologies using the single-particle soot photometer (SP2)

    SciTech Connect (OSTI)

    Sedlacek, III, Arthur J.; Lewis, Ernie R.; Onasch, Timothy B.; Lambe, Andrew T.; Davidovits, Paul

    2015-07-24

    An important source of uncertainty in radiative forcing by absorbing aerosol particles is the uncertainty in their morphologies (i.e., the location of the absorbing substance on/in the particles). To examine the effects of particle morphology on the response of an individual black carbon-containing particle in a Single-Particle Soot Photometer (SP2), a series of experiments was conducted to investigate black carbon-containing particles of known morphology using Regal black (RB), a proxy for collapsed soot, as the light-absorbing substance. Particles were formed by coagulation of RB with either a solid substance (sodium chloride or ammonium sulfate) or a liquid substance (dioctyl sebacate), and by condensation with dioctyl sebacate, the latter experiment forming particles in a core-shell configuration. Each particle type experienced fragmentation (observed as negative lagtimes), and each yielded similar lagtime responses in some instances, confounding attempts to differentiate particle morphology using current SP2 lagtime analysis. SP2 operating conditions, specifically laser power and sample flow rate, which in turn affect the particle heating and dissipation rates, play an important role in the behavior of particles in the SP2, including probability of fragmentation. This behavior also depended on the morphology of the particles and on the thermo-chemical properties of the non-RB substance. Although these influences cannot currently be unambiguously separated, the SP2 analysis may still provide useful information on particle mixing states and black carbon particle sources.

  12. Stability and Regeneration of Catalysts for the Destruction of Tars from Bio-mass Black Liquor Gasification

    SciTech Connect (OSTI)

    Pradeep Agrawal

    2004-09-07

    The goal of this project was to develop catalytic materials and processes that would be effective in the destruction of tars formed during the gasification of black liquor and biomass. We report here the significant results obtained at the conclusion of this two year project.

  13. A Study of the Optical Properties of Ice Crystals with Black Carbon Inclusions

    SciTech Connect (OSTI)

    Arienti, Marco; Yang, Xiaoyuan; Kopacz, Adrian M; Geier, Manfred

    2015-09-01

    The report focu ses on the modification of the optical properties of ice crystals due to atmospheric black car bon (BC) contamination : the objective is to advance the predictive capabilities of climate models through an improved understanding of the radiative properties of compound particles . The shape of the ice crystal (as commonly found in cirrus clouds and cont rails) , the volume fraction of the BC inclusion , and its location inside the crystal are the three factors examined in this study. In the multiscale description of this problem, where a small absorbing inclusion modifies the optical properties of a much la rger non - absorbing particle, state - of - the - art discretization techniques are combined to provide the best compromise of flexibility and accuracy over a broad range of sizes .

  14. Low-Frequency Interlayer Breathing Modes in Few-Layer Black Phosphorus

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ling, Xi; Liang, Liangbo; Huang, Shengxi; Puretzky, Alexander A.; Geohegan, David B.; Sumpter, Bobby G.; Kong, Jing; Meunier, Vincent; Dresselhaus, Mildred S.

    2015-05-08

    As a new two-dimensional layered material, black phosphorus (BP) is a very promising material for nanoelectronics and nano-optoelectronics. We use Raman spectroscopy and first-principles theory to characterize and understand low-frequency (LF) interlayer breathing modes (<100 cm-1) in few-layer BP for the first time. Using laser polarization dependence study and group theory analysis the breathing modes are assigned to Ag symmetry. Compared to the high-frequency (HF) Raman modes, the LF breathing modes are considerably more sensitive to interlayer coupling and thus their frequencies show stronger dependence on the number of layers. Hence, they constitute an effective means to probe both themore » crystalline orientation and thickness of few-layer BP. Furthermore, the temperature dependence shows that the breathing modes have a harmonic behavior, in contrast to HF Raman modes which exhibit anharmonicity.« less

  15. AmeriFlux CA-Qcu Quebec - Eastern Boreal, Black Spruce/Jack Pine Cutover

    SciTech Connect (OSTI)

    Margolis, Hank A.

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site CA-Qcu Quebec - Eastern Boreal, Black Spruce/Jack Pine Cutover. Site Description - The ground is gently rolling with a weak slope (<5%). In mesic areas (designated as well to moderately well drained areas, according to the Canadian System of Soil Classification (Agriculture Canada Expert Committee on Soil Survey, 1983)), the soil is a ferro-humic to humic podzol covered by an organic layer having an average depth of 26 cm (Fig. 1). In humid areas, the soil is organic (imperfectly to poorly drained) with an average organic layer of 125 cm. Mesic areas accounted for approximately 75% of the total surface area of the footprint and humid areas accounted for 25%. Full-time continuous measurements eneded in 2011. Intermittent measurements are on-going as resources permit.

  16. Radiating black holes in Einstein-Yang-Mills theory and cosmic censorship

    SciTech Connect (OSTI)

    Ghosh, Sushant G.; Dadhich, Naresh

    2010-08-15

    Exact nonstatic spherically symmetric black-hole solutions of the higher dimensional Einstein-Yang-Mills equations for a null dust with Yang-Mills gauge charge are obtained by employing Wu-Yang ansatz, namely, HD-EYM Vaidya solution. It is interesting to note that gravitational contribution of Yang-Mills (YM) gauge charge for this ansatz is indeed opposite (attractive rather than repulsive) that of Maxwell charge. It turns out that the gravitational collapse of null dust with YM gauge charge admits strong curvature shell focusing naked singularities violating cosmic censorship. However, there is significant shrinkage of the initial data space for a naked singularity of the HD-Vaidya collapse due to presence of YM gauge charge. The effect of YM gauge charge on structure and location of the apparent and event horizons is also discussed.

  17. Small black holes on branes: Is the horizon regular or singular?

    SciTech Connect (OSTI)

    Karasik, D.; Sahabandu, C.; Suranyi, P.; Wijewardhana, L.C.R.

    2004-09-15

    We investigate the following question: Consider a small mass, with {epsilon} (the ratio of the Schwarzschild radius and the bulk curvature length) much smaller than 1, that is confined to the TeV brane in the Randall-Sundrum I scenario. Does it form a black hole with a regular horizon, or a naked singularity? The metric is expanded in {epsilon} and the asymptotic form of the metric is given by the weak field approximation (linear in the mass). In first order of {epsilon} we show that the iteration of the weak field solution, which includes only integer powers of the mass, leads to a solution that has a singular horizon. We find a solution with a regular horizon but its asymptotic expansion in the mass also contains half integer powers.

  18. Low-frequency Interlayer Breathing Modes in Few-layer Black Phosphorus

    SciTech Connect (OSTI)

    Huang, Shengxi; Puretzky, Alexander A; Geohegan, David B; Sumpter, Bobby G; Kong, Jing; Dresselhaus, M; Meunier, V.; Liang, Liangbo; Ling, Xi

    2015-01-01

    As a new two-dimensional layered material, black phosphorus (BP) is a very promising material for nanoelectronics and nano-optoelectronics. We use Raman spectroscopy and first-principles theory to characterize and understand low-frequency (LF) interlayer breathing modes (<100 cm-1) in few-layer BP for the first time. Using laser polarization dependence study and group theory analysis the breathing modes are assigned to Ag symmetry. Compared to the high-frequency (HF) Raman modes, the LF breathing modes are considerably more sensitive to interlayer coupling and thus their frequencies show stronger dependence on the number of layers. Hence, they constitute an effective means to probe both the crystalline orientation and thickness of few-layer BP. Furthermore, the temperature dependence shows that the breathing modes have a harmonic behavior, in contrast to HF Raman modes which exhibit anharmonicity.

  19. The importance of China's household sector for black carbon emissions - article no. L12708

    SciTech Connect (OSTI)

    Streets, D.G.; Aunan, K.

    2005-06-30

    The combustion of coal and biofuels in Chinese households is a large source of black carbon (BC), representing about 10-15% of total global emissions during the past two decades, depending on the year. How the Chinese household sector develops during the next 50 years will have an important bearing on future aerosol concentrations, because the range of possible outcomes (about 550 Gg yr{sup -1}) is greater than total BC emissions in either the United States or Europe (each about 400-500 Gg yr{sup -1}). In some Intergovernmental Panel on Climate Change scenarios biofuels persist in rural China for at least the next 50 years, whereas in other scenarios a transition to cleaner fuels and technologies effectively mitigates BC emissions. This paper discusses measures and policies that would help this transition and also raises the possibility of including BC emission reductions as a post-Kyoto option for China and other developing countries.

  20. Decadal growth of black carbon emissions in India - article no. L02807

    SciTech Connect (OSTI)

    Sahu, S.K.; Beig, G.; Sharma, C.

    2008-01-15

    A Geographical Information System (GIS) based methodology has been used to construct the black carbon (BC) emission inventory for the Indian geographical region. The distribution of emissions from a broader level to a spatial resolution of 1{sup o} x 1{sup o} grid has been carried out by considering micro level details and activity data of fossil fuels and bio-fuels. Our calculated total BC emissions were 1343.78 Gg and 835.50 Gg for the base years 2001 and 1991 respectively with a decadal growth of around 61%, which is highly significant. The district level analysis shows a diverse spatial distribution with the top 10% emitting districts contributing nearly 50% of total BC emission. Coal contributes more than 50% of total BC emission. All the metropolitan cities show high BC emissions due to high population density giving rise to high vehicular emissions and more demand of energy.