Sample records for black warrior sub-soil

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

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

    Black Warrior: Sub-soil gas and fluid inclusion exploration and slim well drilling John Casteel Nevada Geothermal Power Co. Validation of Innovative Exploration Technologies May...

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

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

    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...

  3. Black Warrior: Sub-soil Gas and Fluid Inclusion Exploration and Slim Well

    Open Energy Info (EERE)

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  4. E-Print Network 3.0 - appalachian black warrior Sample Search...

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

    Summary: and in the acquisition of new properties in the Black Warrior Basin of Alabama (coalbed methane Source: Texas at Austin, University of - George E. Brown, Jr. Network for...

  5. Black Warrior Geothermal Area | Open Energy Information

    Open Energy Info (EERE)

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  6. Black Warrior Geothermal Area | Open Energy Information

    Open Energy Info (EERE)

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  7. 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.

    1994-04-01T23:59:59.000Z

    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.

  8. 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.

    1994-06-01T23:59:59.000Z

    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.

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

    Open Energy Info (EERE)

    identified by reconnaissance temperature gradient drilling in the 1980s by Philips Petroleum but was never tested through deep exploration drilling. Although the 10 square miles...

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

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

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  11. Reservoir heterogeneity in Carter Sandstone, North Blowhorn Creek oil unit and vicinity, Black Warrior Basin, Alabama

    SciTech Connect (OSTI)

    Kugler, R.L.; Pashin, J.C.

    1992-05-01T23:59:59.000Z

    This report presents accomplishments made in completing Task 3 of this project which involves development of criteria for recognizing reservoir heterogeneity in the Black Warrior basin. The report focuses on characterization of the Upper Mississippian Carter sandstone reservoir in North Blowhorn Creek and adjacent oil units in Lamar County, Alabama. This oil unit has produced more than 60 percent of total oil extracted from the Black Warrior basin of Alabama. The Carter sandstone in North Blowhorn Creek oil unit is typical of the most productive Carter oil reservoirs in the Black Warrior basin of Alabama. The first part of the report synthesizes data derived from geophysical well logs and cores from North Blowhorn Creek oil unit to develop a depositional model for the Carter sandstone reservoir. The second part of the report describes the detrital and diagenetic character of Carter sandstone utilizing data from petrographic and scanning electron microscopes and the electron microprobe. The third part synthesizes porosity and pore-throat-size-distribution data determined by high-pressure mercury porosimetry and commercial core analyses with results of the sedimentologic and petrographic studies. The final section of the report discusses reservoir heterogeneity within the context of the five-fold classification of Moore and Kugler (1990).

  12. Assessment of undiscovered carboniferous coal-bed gas resources of the Appalachian Basin and Black Warrior Basin Provinces, 2002

    SciTech Connect (OSTI)

    Milici, R.C.; Hatch, J.R.

    2004-09-15T23:59:59.000Z

    Coalbed methane (CBM) occurs in coal beds of Mississippian and Pennsylvanian (Carboniferous) age in the Appalachian basin, which extends almost continuously from New York to Alabama. In general, the basin includes three structural subbasins: the Dunkard basin in Pennsylvania, Ohio, and northern West Virginia; the Pocahontas basin in southern West Virginia, eastern Kentucky, and southwestern Virginia; and the Black Warrior basin in Alabama and Mississippi. For assessment purposes, the Appalachian basin was divided into two assessment provinces: the Appalachian Basin Province from New York to Alabama, and the Black Warrior Basin Province in Alabama and Mississippi. By far, most of the coalbed methane produced in the entire Appalachian basin has come from the Black Warrior Basin Province. 8 refs., 1 fig., 1 tab.

  13. Area balance and strain in coalbed methane reservoirs of the Black Warrior basin

    SciTech Connect (OSTI)

    Pashin, J.C. [Geological Survey of Alabama, Tuscaloosa, AL (United States); Groshong, R.H., Jr. [Univ. of Alabama, Tuscaloosa, AL (United States)

    1996-09-01T23:59:59.000Z

    Investigation of coalbed methane reservoirs in the Black Warrior basin of Alabama has established a correspondence between productivity and structural position, but the reasons for this correspondence remain uncertain. In Cedar Cove field, for example, exceptionally productive wells are concentrated in a rollover anticline, whereas in Oak Grove field, exceptionally productive wells are aligned along a synclinal axis. This suggests that factors controlling gas production are a derivative of the structural geometry, and not the geometry by itself. Natural fractures and a low state of in-situ stress facilitate depressurization of coalbed reservoirs by dewatering, and hence, desorption and production of coalbed gas. Our hypothesis is that the abundance and openness of natural fractures in the Black Warrior basin are a direct expression of the layer-parallel strain dictated by map-scale structural geometry. Area balancing techniques can be used to quantify requisite strain, which is the homogeneous layer-parallel strain required for local area balance, and can also be used to constrain and verify structural cross sections. Application of area balancing techniques to extensional structures in the Black Warrior basin indicates that coalbed gas is produced from thin-skinned structures detached within the coal-bearing Pottsville Formation. Within reservoir intervals, requisite strain values are as high as 10 percent and increase downward toward the basal detachment. Mapping structure and production indicates that some productivity sweet spots correlate with enhanced bed curvature. Whereas requisite strain is the homogeneous strain calculated for discrete bed segments, curvature affects the distribution of strain within those segments. Recognizing this, our research is now focused on integrating area balancing techniques with curvature analysis to explain production patterns in coalbed methane reservoirs.

  14. 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.

    1992-07-01T23:59:59.000Z

    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.

  15. 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.

    1992-07-01T23:59:59.000Z

    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.

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

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

    Open Energy Info (EERE)

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  18. Black Warrior Elec Member Corp | Open Energy Information

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  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

    2004-01-01T23:59:59.000Z

    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 Alabama emit approximately 31 MMst (2.4 Tcf) of CO{sub 2} annually. The total sequestration capacity of the Black Warrior coalbed methane fairway at 350 psi is about 189 MMst (14.9 Tcf), which is equivalent to 6.1 years of greenhouse gas emissions from the coal-fired power plants. Applying the geologic screening model indicates that significant parts of the coalbed methane fairway are not accessible because of fault zones, coal mines, coal reserves, and formation water with TDS content less than 3,000 mg/L. Excluding these areas leaves a sequestration potential of 60 MMst (4.7 Tcf), which is equivalent to 1.9 years of emissions. Therefore, if about10 percent of the flue gas stream from nearby power plants is dedicated to enhanced coalbed methane recovery, a meaningful reduction of CO{sub 2} emissions can be realized for nearly two decades. If the fresh-water restriction were removed for the purposes of CO{sub 2} sequestration, an additional 10 MMst (0.9 Tcf) of CO{sub 2} could feasibly be sequestered. The amount of unswept coalbed methane in the fairway is estimated to be 1.49 Tcf at a pressure of 50 psi. Applying the screening model results in an accessible unswept gas resource of 0.44 Tcf. Removal of the fresh-water restriction would elevate this number to 0.57 Tcf. If a recovery factor of 80 percent can be realized, then enhanced recovery activities can result in an 18 percent expansion of coalbed methane reserves in the Black Warrior basin.

  20. 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

    2013-10-31T23:59:59.000Z

    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 tends to decline hyperbolically. Hyperbolic decline indicates that water volume is of greatest concern early in the life of a coalbed methane project. Regional mapping indicates that gas production is controlled primarily by the ability to depressurize permeable coal seams that are natively within the steep part of the adsorption isotherm. Water production is greatest within the freshwater intrusion and below thick Cretaceous cover strata and is least in areas of underpressure. Water management strategies include instream disposal, which can be applied effectively in most parts of the basin. Deep disposal may be applicable locally, particularly where high salinity limits the ability to dispose into streams. Artificial wetlands show promise for the management of saline water, especially where the reservoir yield is limited. Beneficial use options include municipal water supply, agricultural use, and industrial use. The water may be of use to an inland shrimp farming industry, which is active around the southwestern coalbed methane fields. The best opportunities for beneficial use are reuse of water by the coalbed methane industry for drilling and hydraulic fracturing. This research has further highlighted opportunities for additional research on treatment efficiency, the origin of nitrogen compounds, organic geochemistry, biogenic gas generation, flow modeling, and computer simulation. Results of this study are being disseminated through a vigorous technology transfer program that includes web resources, numerous presentations to stakeholders, and a variety of technical publications.

  1. 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

    2003-01-01T23:59:59.000Z

    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 reactivity of supercritical CO{sub 2} in coal-bearing strata is unknown, and potential exists for supercritical conditions to develop below a depth of 2,480 feet following abandonment of the coalbed methane fields. High-pressure adsorption isotherms confirm that coal sorbs approximately twice as much CO{sub 2} as CH{sub 4} and approximately four times as much CO{sub 2} as N{sub 2}. Analysis of isotherm data reveals that the sorption performance of each gas can vary by a factor of two depending on rank and ash content. Gas content data exhibit extreme vertical and lateral variability that is the product of a complex burial history involving an early phase of thermogenic gas generation and an ongoing stage of late biogenic gas generation. Production characteristics of coalbed methane wells are helpful for identifying areas that are candidates for carbon sequestration and enhanced coalbed methane recovery. Many geologic and engineering factors, including well construction, well spacing, and regional structure influence well performance. Close fault spacing limits areas where five-spot patterns may be developed for enhanced gas recovery, but large structural panels lacking normal faults are in several gas fields and can be given priority as areas to demonstrate and commercialize carbon sequestration technology in coalbed methane reservoirs.

  2. Adsorption Kinetics of CO2, CH4, and their Equimolar Mixture on Coal from the Black Warrior Basin, West-Central Alabama

    SciTech Connect (OSTI)

    Gruszkiewicz, Miroslaw {Mirek} S [ORNL; Naney, Michael {Mike} T [ORNL; Blencoe, James {Jim} G [ORNL; Cole, David R [ORNL; Pashin, Jack C. [Geological Survey of Alabama; Carroll, Richard E. [Geological Survey of Alabama

    2009-01-01T23:59:59.000Z

    Laboratory experiments were conducted to investigate the adsorption kinetic behavior of pure and mixed gases (CO2, CH4, approximately equimolar CO2 + CH4 mixtures, and He) on a coal sample obtained from the Black Warrior Basin at the Littleton Mine (Twin Pine Coal Company), Jefferson County, west-central Alabama. The sample was from the Mary Lee coal zone of the Pottsville Formation (Lower Pennsylvanian). Experiments with three size fractions (45-150 m, 1-2 mm, and 5-10 mm) of crushed coal were performed at 40 C and 35 C over a pressure range of 1.4 6.9 MPa to simulate coalbed methane reservoir conditions in the Black Warrior Basin and provide data relevant for enhanced coalbed methane recovery operations. The following key observations were made: (1) CO2 adsorption on both dry and water-saturated coal is much more rapid than CH4 adsorption; (2) water saturation decreases the rates of CO2 and CH4 adsorption on coal surfaces, but it appears to have minimal effects on the final magnitude of CO2 or CH4 adsorption if the coal is not previously exposed to CO2; (3) retention of adsorbed CO2 on coal surfaces is significant even with extreme pressure cycling; and (4) adsorption is significantly faster for the 45-150 m size fraction compared to the two coarser fractions.

  3. 2-M Probe At Black Warrior Area (DOE GTP) | Open Energy Information

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  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

    2012-08-31T23:59:59.000Z

    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 for carbon dioxide injection, there is still a large storage capacity in the basin to the west of the power plants. It will, however, require pipeline construction to transport the carbon dioxide to the injection sites.

  5. Overview of GRI research at the Rock Creek Site, Black Warrior Basin. Overview of GRI research at Rock Creek: Eight years of cooperative research, coalbed methane shortcourse. Held in Abingdon, Virginia on October 23, 1992. Topical report

    SciTech Connect (OSTI)

    Schraufnagel, R.

    1992-10-01T23:59:59.000Z

    The presentation slides from the October 23, 1992 workshop on coalbed methane exploration and production are assembled in this volume. They illustrate the following discussions: Overview of GRI Research at Rock Creek: Eight Years of Cooperative Research, Drilling and Completing Coalbed Methane Wells: Techniques for Fragile Formations, Connecting the Wellborne to the Formation: Perforations vs. Slotting, Coalbed Methane Well Testing in the Warrior Basin, Reservoir Engineering: A Case Study at Rock Creek, Fraccing of Multiple Thin Seams: Considerations and Constraints, Implementing Coal Seam Stimulations: Requirements for Successful Treatments, Coal-Fluid Interactions, Mine-Through Observations of Coal Seam Stimulations: Reality vs. Theory, and Recompleting Coalbed Methane Wells: The Second Try at Success.

  6. The Myth of the Woman Warrior and World War II in Soviet Culture

    E-Print Network [OSTI]

    Harris, Adrienne

    2008-07-29T23:59:59.000Z

    "The Myth of the Woman Warrior and World War II in Soviet Culture" defines, analyzes, and explains the figure of the Soviet "woman warrior" who participated in World War II, asking the questions: what is the nature of the ...

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

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

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

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 NoPublicIDAPowerPlantSitingConstruction.pdf JumpApschem.pdf Jump to:December 2010 Thumbnailpixels. Full

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

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 NoPublicIDAPowerPlantSitingConstruction.pdf JumpApschem.pdf Jump to:December 2010 Thumbnailpixels. FullFile history

  11. Modeling the resolution of inexpensive, novel non-seismic geophysical monitoring tools to monitor CO2 injection into coal beds

    E-Print Network [OSTI]

    Gasperikova, E.

    2010-01-01T23:59:59.000Z

    Warrior basin in Alabama. Coal seams in the Black WarriorWarrior basin in Alabama. Coal seams in the Black Warrior

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

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 No revisionEnvReviewNonInvasiveExplorationUT-g Grant ofRichardtonManagement, 2009) | OpenSixthSkypointDoDBlack

  13. Compound and Elemental Analysis At Black Warrior Area (DOE GTP) | Open

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of InspectorConcentratingRenewable Solutions LLC Jump to: navigation, search Name:CXD)2010) | OpenOpenOpenEnergy

  14. Core Analysis At Black Warrior Area (DOE GTP) | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of InspectorConcentratingRenewable Solutions LLC Jump to:Information NewAdvisors Jump to:

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

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of InspectorConcentratingRenewable Solutions LLC JumpCrow Lake Wind Jump to:Roadmap MeetingInformation

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

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia: Energy Resources Jump to: navigation, search Equivalent6894093° Loading69. ItLewicki & Oldenburg,EnergyArea

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

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia: Energy Resources Jump to: navigation, search Equivalent6894093° Loading69. ItLewickiMauiSL Jump to:

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

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 NoPublicIDAPowerPlantSitingConstruction.pdf JumpApschem.pdf Jump to: navigation, searchBanglmetst 221.pdf Jump

  19. 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

    2011-05-10T23:59:59.000Z

    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.

  20. Potential for CO2 Sequestration and Enhanced Coalbed Methane Production, Blue Creek Field, NW Black Warrior Basin, Alabama

    E-Print Network [OSTI]

    He, Ting

    2011-02-22T23:59:59.000Z

    Carbon dioxide (CO2) is a primary source of greenhouse gases. Injection of CO2 from power plants near coalbed reservoirs is a win-win method to reducing emissions of CO2 to the atmosphere. Limited studies have investigated CO2 sequestration...

  1. Black Holes

    E-Print Network [OSTI]

    P. K. Townsend

    1997-07-04T23:59:59.000Z

    Lecture notes for a 'Part III' course 'Black Holes' given in DAMTP, Cambridge. The course covers some of the developments in Black Hole physics of the 1960s and 1970s.

  2. 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.

    2010-09-01T23:59:59.000Z

    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.

  3. Carbon smackdown: wind warriors

    SciTech Connect (OSTI)

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

    2010-07-21T23:59:59.000Z

    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.

  4. 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.

  5. Black Hole Chemistry

    E-Print Network [OSTI]

    David Kubiznak; Robert B. Mann

    2014-04-08T23:59:59.000Z

    The mass of a black hole has traditionally been identified with its energy. We describe a new perspective on black hole thermodynamics, one that identifies the mass of a black hole with chemical enthalpy, and the cosmological constant as thermodynamic pressure. This leads to an understanding of black holes from the viewpoint of chemistry, in terms of concepts such as Van der Waals fluids, reentrant phase transitions, and triple points. Both charged and rotating black holes exhibit novel chemical-type phase behaviour, hitherto unseen.

  6. Bicycling Black Rings

    E-Print Network [OSTI]

    Elvang, Henriette

    2008-01-01T23:59:59.000Z

    We present detailed physics analyses of two different 4+1-dimensional asymptotically flat vacuum black hole solutions with spin in two independent planes: the doubly spinning black ring and the bicycling black ring system ("bi-rings"). The latter is a new solution describing two concentric orthogonal rotating black rings which we construct using the inverse scattering technique. We focus particularly on extremal zero-temperature limits of the solutions. Such limits exist for both types of solutions; for the bi-rings it is obtained when the two rings drag each other to extremality through the effect of gravitational frame-dragging. We construct the phase diagram of currently known zero-temperature vacuum black hole solutions with a single event horizon, and discuss the non-uniqueness introduced by more exotic black hole configurations such as bi-rings and multi-ring saturns.

  7. Bicycling Black Rings

    E-Print Network [OSTI]

    Henriette Elvang; Maria J. Rodriguez

    2008-01-25T23:59:59.000Z

    We present detailed physics analyses of two different 4+1-dimensional asymptotically flat vacuum black hole solutions with spin in two independent planes: the doubly spinning black ring and the bicycling black ring system ("bi-rings"). The latter is a new solution describing two concentric orthogonal rotating black rings which we construct using the inverse scattering technique. We focus particularly on extremal zero-temperature limits of the solutions. We construct the phase diagram of currently known zero-temperature vacuum black hole solutions with a single event horizon, and discuss the non-uniqueness introduced by more exotic black hole configurations such as bi-rings and multi-ring saturns.

  8. 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.

  9. A Black Hole Levitron

    E-Print Network [OSTI]

    Xerxes D. Arsiwalla; Erik P. Verlinde

    2009-02-02T23:59:59.000Z

    We study the problem of spatially stabilising four dimensional extremal black holes in background electric/magnetic fields. Whilst looking for stationary stable solutions describing black holes kept in external fields we find that taking a continuum limit of Denef et al's multi-center solutions provides a supergravity description of such backgrounds within which a black hole can be trapped in a given volume. This is realised by levitating a black hole over a magnetic dipole base. We comment on how such a construction resembles a mechanical Levitron.

  10. Dynamics of black holes

    E-Print Network [OSTI]

    Sean A. Hayward

    2009-02-28T23:59:59.000Z

    This is a review of current theory of black-hole dynamics, concentrating on the framework in terms of trapping horizons. Summaries are given of the history, the classical theory of black holes, the defining ideas of dynamical black holes, the basic laws, conservation laws for energy and angular momentum, other physical quantities and the limit of local equilibrium. Some new material concerns how processes such as black-hole evaporation and coalescence might be described by a single trapping horizon which manifests temporally as separate horizons.

  11. U.S. Energy Information Administration (EIA) - Sector

    Gasoline and Diesel Fuel Update (EIA)

    -- -- -- -- 51 41 12 Uinta -- -- -- -- 7 21 11 Permian -- -- -- -- -- 67 27 Greater Green River -- -- -- -- -- 18 13 Black Warrior -- -- -- -- -- 4 5 Shale gas total 83 126 125...

  12. Cold warriors target arms control

    SciTech Connect (OSTI)

    Isaacs, J.

    1995-09-01T23:59:59.000Z

    While disagreements over the conflict in Bosnia have strained US relations with Western Europe and Russia, these divisions will pale in comparison to the tensions that will arise if recent congressional arms control decisions become law. If the Republicans who dominate Congress are successful, a series of arms control agreements painstakingly negotiated by Republican and Democratic presidents could be consigned to the ash heap. This list includes the Start I and Start II nuclear reduction agreements, the 1972 Anti-Ballistic Missile (ABM) Treaty and the ongoing negotiations 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 country`s direction, will question the ability of the executive branch to surmount isolantionist impulses.

  13. "Hybrid" Black Holes

    E-Print Network [OSTI]

    Valeri P. Frolov; Andrei V. Frolov

    2014-12-30T23:59:59.000Z

    We discuss a solution of the Einstein equations, obtained by gluing the external Kerr metric and the internal Weyl metric, describing an axisymmetric static vacuum distorted black hole. These metrics are glued at the null surfaces representing their horizons. For this purpose we use the formalism of massive thin null shells. The corresponding solution is called a "hybrid" black hole. The massive null shell has an angular momentum which is the origin of the rotation of the external Kerr spacetime. At the same time, the shell distorts the geometry inside the horizon. The inner geometry of the "hybrid" black hole coincides with the geometry of the interior of a non-rotating Weyl-distorted black hole. Properties of the "hybrid" black holes are briefly discussed.

  14. Charging Black Saturn?

    E-Print Network [OSTI]

    Brenda Chng; Robert Mann; Eugen Radu; Cristian Stelea

    2008-10-28T23:59:59.000Z

    We construct new charged static solutions of the Einstein-Maxwell field equations in five dimensions via a solution generation technique utilizing the symmetries of the reduced Lagrangian. By applying our method on the multi-Reissner-Nordstrom solution in four dimensions, we generate the multi-Reissner-Nordstrom solution in five dimensions. We focus on the five-dimensional solution describing a pair of charged black objects with general masses and electric charges. This solution includes the double Reissner-Nordstrom solution as well as the charged version of the five-dimensional static black Saturn. However, all the black Saturn configurations that we could find present either a conical singularity or a naked singularity. We also obtain a non-extremal configuration of charged black strings that reduces in the extremal limit to a Majumdar-Papapetrou like solution in five dimensions.

  15. Charged Schrodinger black holes

    E-Print Network [OSTI]

    Adams, Allan

    We construct charged and rotating asymptotically Schrdinger black hole solutions of type IIB supergravity. We begin by obtaining a closed-form expression for the null Melvin twist of a broad class of type IIB backgrounds, ...

  16. Helical superconducting black holes

    E-Print Network [OSTI]

    Aristomenis Donos; Jerome P. Gauntlett

    2012-05-17T23:59:59.000Z

    We construct novel static, asymptotically $AdS_5$ black hole solutions with Bianchi VII$_0$ symmetry that are holographically dual to superconducting phases in four spacetime dimensions with a helical p-wave order. We calculate the precise temperature dependence of the pitch of the helical order. At zero temperature the black holes have vanishing entropy and approach domain wall solutions that reveal homogenous, non-isotropic dual ground states with emergent scaling symmetry.

  17. On Black Hole Entropy

    E-Print Network [OSTI]

    Ted Jacobson; Gungwon Kang; Robert C. Myers

    1994-01-03T23:59:59.000Z

    Two techniques for computing black hole entropy in generally covariant gravity theories including arbitrary higher derivative interactions are studied. The techniques are Wald's Noether charge approach introduced recently, and a field redefinition method developed in this paper. Wald's results are extended by establishing that his local geometric expression for the black hole entropy gives the same result when evaluated on an arbitrary cross-section of a Killing horizon (rather than just the bifurcation surface). Further, we show that his expression for the entropy is not affected by ambiguities which arise in the Noether construction. Using the Noether charge expression, the entropy is evaluated explicitly for black holes in a wide class of generally covariant theories. Further, it is shown that the Killing horizon and surface gravity of a stationary black hole metric are invariant under field redefinitions of the metric of the form $\\bar{g}_{ab}\\equiv g_{ab} + \\Delta_{ab}$, where $\\Delta_{ab}$ is a tensor field constructed out of stationary fields. Using this result, a technique is developed for evaluating the black hole entropy in a given theory in terms of that of another theory related by field redefinitions. Remarkably, it is established that certain perturbative, first order, results obtained with this method are in fact {\\it exact}. The possible significance of these results for the problem of finding the statistical origin of black hole entropy is discussed.}

  18. Gasification of black liquor

    SciTech Connect (OSTI)

    Kohl, A.L.

    1987-07-28T23:59:59.000Z

    A process is described for treating a concentrated aqueous black liquor carbonaceous material and alkali metal sulfur compounds to form a combustible gas and a sulfide-rich melt comprising: (a) providing a gasifier vessel maintained at a pressure of from about 1 to 50 atmospheres and containing a relatively shallow molten salt pool at its bottom within a sump equipped with an overflow discharge; (b) introducing into the top of the drying zone the concentrated aqueous black liquor containing carbonaceous material and alkali metal sulfur compounds; (c) evaporating water from the concentrated aqueous black liquor in the drying zone by direct contact of the aqueous black liquor with the hot gas rising from the gasification zone to produce dried black liquor solids; (d) introducing a first portion of an oxygen-containing gas into the gas space in the gasification zone located below the drying zone immediately above the molten salt pool to partially oxidize and gasify a fraction of the carbonaceous material in the dried black liquor solids falling through the zone to form a hot combustible gas; (e) introducing a second portion of the oxygen-containing gas beneath the surface of the molten salt pool in an amount sufficient to cause gasification of essentially all carbonaceous material entering the pool from the gasification zone but not sufficient to create oxidizing conditions in the pool; (f) withdrawing the cooled combustible gas having a higher heating value of at least about 90 Btu/scf (dry basis) from an upper portion of the drying zone; and (g) withdrawing from the overflow discharge in the molten salt reduction zone a melt in which the sulfur content is predominantly in the form of alkali metal sulfide.

  19. Black holes at accelerators.

    E-Print Network [OSTI]

    Webber, Bryan R

    ar X iv :h ep -p h/ 05 11 12 8v 3 6 A pr 2 00 6 Black Holes at Accelerators Bryan Webber Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, UK In theories with large extra dimensions and TeV-scale gravity, black holes... 2000 3000 Missing ET (GeV) Ar bi tra ry S ca le p p ? QCD SUSY 5 TeV BH (n=6) 5 TeV BH (n=2) (PT > 600 GeV) (SUGRA point 5) Figure 10: Missing transverse energy for various processes at the LHC. 4.2. Event Characteristics Turning from single...

  20. Extremal black disks in QCD

    E-Print Network [OSTI]

    Alexey V. Popov

    2008-05-12T23:59:59.000Z

    We argue that in the high energy QCD a true black disk wave function necessarily contains many quarks. This corresponds to necessity of non-vacuum reggeon loops in formation of a black disk. The result comes from decomposition of the black disk S-matrix in characters on group manifold.

  1. Black holes and black strings in plane waves

    E-Print Network [OSTI]

    Julian Le Witt; Simon F. Ross

    2009-10-30T23:59:59.000Z

    We investigate the construction of black holes and black strings in vacuum plane wave spacetimes using the method of matched asymptotic expansions. We find solutions of the linearised equations of motion in the asymptotic region for a general source on a plane wave background. We observe that these solutions do not satisfy our previously defined conditions for being asymptotically plane wave. Hence, the space of asymptotically plane wave solutions is restricted. We consider the solution in the near region, treating the plane wave as a perturbation of a black object, and find that there is a regular black string solution but no regular black hole solution.

  2. Gasification of black liquor

    DOE Patents [OSTI]

    Kohl, Arthur L. (Woodland Hills, CA)

    1987-07-28T23:59:59.000Z

    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.

  3. Gasification of black liquor

    DOE Patents [OSTI]

    Kohl, A.L.

    1987-07-28T23:59:59.000Z

    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.

  4. Black Hole Thermodynamics Today

    E-Print Network [OSTI]

    Ted Jacobson

    1998-01-07T23:59:59.000Z

    A brief survey of the major themes and developments of black hole thermodynamics in the 1990's is given, followed by summaries of the talks on this subject at MG8 together with a bit of commentary, and closing with a look towards the future.

  5. Combustion of black liquor

    SciTech Connect (OSTI)

    Mullen, W.T.

    1989-08-15T23:59:59.000Z

    This patent describes an improvement in the combustion of black liquor in an existing Tomlison recovery boiler unit in which black liquor is sprayed into a furnace in which it is successively dried, pyrolyzed and converted to a bed of solid carbonaceous residue, using a primary air stream and a secondary air stream and the residue is subsequently converted to a smelt. The improvement comprises: the addition of between an effective amount up to 5% oxygen by volume to the primary air stream directed at the bed of solid carbonaceous residue, the amount of oxygen added being sufficient to increase the adiabatic flame temperature, the combustion rate of the solid carbonaceous material, the rate of pyrolysis, the temperature in the lower portion of the furnace, the the drying rate of black liquor droplets, and to decrease the temperature of the gases entering the heat transfer surfaces in the upper portion of the furnace and the rate of deposit formation on the surfaces and wherein the amount of black liquor combusted is increased as compared with the amount combusted in the same furnace operated without the addition of oxygen to the primary air.

  6. Quantum black hole inflation

    E-Print Network [OSTI]

    M. B. Altaie

    2001-05-07T23:59:59.000Z

    In this paper we follow a new approach for particle creation by a localized strong gravitational field. The approach is based on a definition of the physical vacuum drawn from Heisenberg uncertainty principle. Using the fact that the gravitational field red-shifts the frequency modes of the vacuum, a condition on the minimum stregth of the gravitational field required to achieve real particle creation is derived. Application of this requirement on a Schwartzchid black hole resulted in deducing an upper limit on the region, outside the event horizon, where real particles can be created. Using this regional upper limit, and considering particle creation by black holes as a consequence of the Casimir effect, with the assumption that the created quanta are to be added to the initial energy, we deduce a natural power law for the development of the event horizon, and consequently a logarithmic law for the area spectrum of an inflating black hole. Application of the results on a cosmological model shows that if we start with a Planck-dimensional black hole, then through the process of particle creation we end up with a universe having the presently estimated critical density. Such a universe will be in a state of eternal inflation.

  7. Black brane steady states

    E-Print Network [OSTI]

    Amado, Irene

    2015-01-01T23:59:59.000Z

    We follow the evolution of an asymptotically AdS black brane with a fixed temperature gradient at spatial infinity until a steady state is formed. The resulting energy density and energy flux of the steady state in the boundary theory are compared to a conjecture on the behavior of steady states in conformal field theories. Very good agreement is found.

  8. BLACK HOLE AURORA POWERED BY A ROTATING BLACK HOLE

    SciTech Connect (OSTI)

    Takahashi, Masaaki [Department of Physics and Astronomy, Aichi University of Education, Kariya, Aichi 448-8542 (Japan); Takahashi, Rohta, E-mail: takahasi@phyas.aichi-edu.ac.j [Cosmic Radiation Laboratory, Institute of Physical and Chemical Research, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan)

    2010-05-15T23:59:59.000Z

    We present a model for high-energy emission sources generated by a standing magnetohydrodynamical (MHD) shock in a black hole magnetosphere. The black hole magnetosphere would be constructed around a black hole with an accretion disk, where a global magnetic field could be originated by currents in the accretion disk and its corona. Such a black hole magnetosphere may be considered as a model for the central engine of active galactic nuclei, some compact X-ray sources, and gamma-ray bursts. The energy sources of the emission from the magnetosphere are the gravitational and electromagnetic energies of magnetized accreting matters and the rotational energy of a rotating black hole. When the MHD shock generates in MHD accretion flows onto the black hole, the plasma's kinetic energy and the black hole's rotational energy can convert to radiative energy. In this Letter, we demonstrate the huge energy output at the shock front by showing negative energy postshock accreting MHD flows for a rapidly rotating black hole. This means that the extracted energy from the black hole can convert to the radiative energy at the MHD shock front. When an axisymmetric shock front is formed, we expect a ring-shaped region with very hot plasma near the black hole; this would look like an 'aurora'. The high-energy radiation generated from there would carry to us the information for the curved spacetime due to the strong gravity.

  9. Supermassive Black Holes

    E-Print Network [OSTI]

    Fulvio Melia

    2007-05-10T23:59:59.000Z

    Supermassive black holes have generally been recognized as the most destructive force in nature. But in recent years, they have undergone a dramatic shift in paradigm. These objects may have been critical to the formation of structure in the early universe, spawning bursts of star formation and nucleating proto-galactic condensations. Possibly half of all the radiation produced after the Big Bang may be attributed to them, whose number is now known to exceed 300 million. The most accessible among them is situated at the Center of Our Galaxy. In the following pages, we will examine the evidence that has brought us to this point, and we will understand why many expect to actually image the event horizon of the Galaxy's central black hole within this decade.

  10. Shape of black holes

    E-Print Network [OSTI]

    Clement, Mara E Gabach

    2015-01-01T23:59:59.000Z

    It is well known that celestial bodies tend to be spherical due to gravity and that rotation produces deviations from this sphericity. We discuss what is known and expected about the shape of black holes' horizons from their formation to their final, stationary state. We present some recent results showing that black hole rotation indeed manifests in the widening of their central regions, limits their global shapes and enforces their whole geometry to be close to the extreme Kerr horizon geometry at almost maximal rotation speed. The results depend only on the horizon area and angular momentum. In particular they are entirely independent of the surrounding geometry of the spacetime and of the presence of matter satisfying the strong energy condition. We also discuss the the relation of this result with the Hoop conjecture.

  11. Black Pine Circle Project

    SciTech Connect (OSTI)

    Mytko, Christine

    2014-03-31T23:59:59.000Z

    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.

  12. Black Pine Circle Project

    ScienceCinema (OSTI)

    Mytko, Christine

    2014-09-15T23:59:59.000Z

    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.

  13. Red-black Tree Jingjing Xia

    E-Print Network [OSTI]

    Chen, Yangjun

    Advanced Algorithm Design Red-black Tree Jingjing Xia #12;Red-Black Tree A red-black tree is a binary search tree, and each node contains one extra field: its color, it can be either black or red of the binary search tree. If a binary search tree satisfies all the following red-black properties, it is a red

  14. Black holes in massive gravity

    E-Print Network [OSTI]

    Babichev, Eugeny

    2015-01-01T23:59:59.000Z

    We review the black hole solutions of the ghost-free massive gravity theory and its bimetric extension and outline the main results on the stability of these solutions against small perturbations. Massive (bi)-gravity accommodates exact black hole solutions, analogous to those of General Relativity. In addition to these solutions, hairy black holes -- solutions with no correspondent in General Relativity -- have been found numerically, whose existence is a natural consequence of the absence of the Birkhoff's theorem in these theories. The existence of extra propagating degrees of freedom, makes the stability properties of these black holes richer and more complex than those of General Relativity. In particular, the bi-Schwarzschild black hole exhibits an unstable spherically symmetric mode, while the bi-Kerr geometry is also generically unstable, both against the spherical mode and against superradiant instabilities. If astrophysical black holes are described by these solutions, the superradiant instability o...

  15. Black Hole's 1/N Hair

    E-Print Network [OSTI]

    Gia Dvali; Cesar Gomez

    2012-03-29T23:59:59.000Z

    According to the standard view classically black holes carry no hair, whereas quantum hair is at best exponentially weak. We show that suppression of hair is an artifact of the semi-classical treatment and that in the quantum picture hair appears as an inverse mass-square effect. Such hair is predicted in the microscopic quantum description in which a black hole represents a self-sustained leaky Bose-condensate of N soft gravitons. In this picture the Hawking radiation is the quantum depletion of the condensate. Within this picture we show that quantum black hole physics is fully compatible with continuous global symmetries and that global hair appears with the strength B/N, where B is the global charge swallowed by the black hole. For large charge this hair has dramatic effect on black hole dynamics. Our findings can have interesting astrophysical consequences, such as existence of black holes with large detectable baryonic and leptonic numbers.

  16. Observational Evidence for Black Holes

    E-Print Network [OSTI]

    Ramesh Narayan; Jeffrey E. McClintock

    2014-07-20T23:59:59.000Z

    Astronomers have discovered two populations of black holes: (i) stellar-mass black holes with masses in the range 5 to 30 solar masses, millions of which are present in each galaxy in the universe, and (ii) supermassive black holes with masses in the range 10^6 to 10^{10} solar masses, one each in the nucleus of every galaxy. There is strong circumstantial evidence that all these objects are true black holes with event horizons. The measured masses of supermassive black hole are strongly correlated with properties of their host galaxies, suggesting that these black holes, although extremely small in size, have a strong influence on the formation and evolution of entire galaxies. Spin parameters have recently been measured for a handful of black holes. Based on the data, there is an indication that the kinetic power of at least one class of relativistic jet ejected from accreting black holes may be correlated with black hole spin. If verified, it would suggest that these jets are powered by a generalized Penrose process mediated by magnetic fields.

  17. Why Blue-Collar Blacks Help Less

    E-Print Network [OSTI]

    Smith, Sandra Susan; Young, Kara Alexis

    2013-01-01T23:59:59.000Z

    In Hispanics in the Why Blacks Help Less U.S. Economy, eds.71(1):42-71. Why Blacks Help Less Fernandez, Roberto M. andProblems 49 (1): 11- Why Blacks Help Less Heflin, Coleen M.

  18. Black-white asymmetry in visual perception

    E-Print Network [OSTI]

    Lu, Z.-L.; Sperling, G.

    2012-01-01T23:59:59.000Z

    tion of black and white in human vision. Investi- gativeneural responses to black and white ments are balanced, weand observers. The black white asymmetry with a 1.28 is

  19. Why Blue-Collar Blacks Help Less

    E-Print Network [OSTI]

    Smith, Sandra Susan; Young, Kara Alexis

    2013-01-01T23:59:59.000Z

    Exclude Black Men from Blue-Collar Jobs. Berkeley, CA:How Black and Latino Blue Collar Workers Make Decisionsof Sample Respondents Blue-Collar Latinos Blue-Collar Black

  20. RHIC | Black Holes?

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas ConchasPassive Solar HomePromising Science for1 20115, 2001 MediaBrookhavenBlack Holes at

  1. ARM - Black Forest News

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary)morphinanInformation Desert SouthwestTechnologies |NovemberARMContactsARM Engineering6,GermanyBlack Forest News

  2. RHIC | Black Holes?

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 -the Mid-Infrared at 278, 298, and 323 K.Office ofMayPVREPORTPortalPriceA/4Black

  3. Black Stars and Gamma Ray Bursts

    E-Print Network [OSTI]

    Tanmay Vachaspati

    2007-06-08T23:59:59.000Z

    Stars that are collapsing toward forming a black hole but are frozen near the Schwarzschild horizon are termed ``black stars''. Collisions of black stars, in contrast to black hole collisions, may be sources of gamma ray bursts, whose basic parameters are estimated quite simply and are found to be consistent with observed gamma ray bursts. Black star gamma ray bursts should be preceded by gravitational wave emission similar to that from the coalescence of black holes.

  4. Optical black holes and solitons

    E-Print Network [OSTI]

    Shawn Westmoreland

    2010-12-21T23:59:59.000Z

    We exhibit a static, cylindrically symmetric, exact solution to the Euler-Heisenberg field equations (EHFE) and prove that its effective geometry contains (optical) black holes. It is conjectured that there are also soliton solutions to the EHFE which contain black hole geometries.

  5. Entropy of Lovelock Black Holes

    E-Print Network [OSTI]

    Ted Jacobson; Robert C. Myers

    1993-05-06T23:59:59.000Z

    A general formula for the entropy of stationary black holes in Lovelock gravity theories is obtained by integrating the first law of black hole mechanics, which is derived by Hamiltonian methods. The entropy is not simply one quarter of the surface area of the horizon, but also includes a sum of intrinsic curvature invariants integrated over a cross section of the horizon.

  6. Black Holes of Negative Mass

    E-Print Network [OSTI]

    R. B. Mann

    1997-05-06T23:59:59.000Z

    I demonstrate that, under certain circumstances, regions of negative energy density can undergo gravitational collapse into a black hole. The resultant exterior black hole spacetimes necessarily have negative mass and non-trivial topology. A full theory of quantum gravity, in which topology-changing processes take place, could give rise to such spacetimes.

  7. Black optic display

    DOE Patents [OSTI]

    Veligdan, James T. (Manorville, NY)

    1997-01-01T23:59:59.000Z

    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.

  8. Thermodynamics of regular black hole

    E-Print Network [OSTI]

    Yun Soo Myung; Yong-Wan Kim; Young-Jai Park

    2008-09-21T23:59:59.000Z

    We investigate thermodynamics for a magnetically charged regular black hole (MCRBH), which comes from the action of general relativity and nonlinear electromagnetics, comparing with the Reissner-Norstr\\"om (RN) black hole in both four and two dimensions after dimensional reduction. We find that there is no thermodynamic difference between the regular and RN black holes for a fixed charge $Q$ in both dimensions. This means that the condition for either singularity or regularity at the origin of coordinate does not affect the thermodynamics of black hole. Furthermore, we describe the near-horizon AdS$_2$ thermodynamics of the MCRBH with the connection of the Jackiw-Teitelboim theory. We also identify the near-horizon entropy as the statistical entropy by using the AdS$_2$/CFT$_1$ correspondence.

  9. Black Hole Interior Mass Formula

    E-Print Network [OSTI]

    Parthapratim Pradhan

    2014-05-06T23:59:59.000Z

    We argue by explicit computations that, although the area product, horizon radii product, entropy product and \\emph {irreducible mass product} of the event horizon and Cauchy horizon are universal, the \\emph{surface gravity product}, \\emph{surface temperature product} and \\emph{Komar energy product} of the said horizons do not seem to be universal for Kerr-Newman (KN) black hole space-time. We show the black hole mass formula on the \\emph{Cauchy horizon} following the seminal work by Smarr\\cite{smarr} for the outer horizon. We also prescribed the \\emph{four} laws of black hole mechanics for the \\emph{inner horizon}. New definition of the extremal limit of a black hole is discussed.

  10. Lattice Black Holes

    E-Print Network [OSTI]

    Steven Corley; Ted Jacobson

    1998-03-26T23:59:59.000Z

    We study the Hawking process on lattices falling into static black holes. The motivation is to understand how the outgoing modes and Hawking radiation can arise in a setting with a strict short distance cutoff in the free-fall frame. We employ two-dimensional free scalar field theory. For a falling lattice with a discrete time-translation symmetry we use analytical methods to establish that, for Killing frequency $\\omega$ and surface gravity $\\kappa$ satisfying $\\kappa\\ll\\omega^{1/3}\\ll 1$ in lattice units, the continuum Hawking spectrum is recovered. The low frequency outgoing modes arise from exotic ingoing modes with large proper wavevectors that "refract" off the horizon. In this model with time translation symmetry the proper lattice spacing goes to zero at spatial infinity. We also consider instead falling lattices whose proper lattice spacing is constant at infinity and therefore grows with time at any finite radius. This violation of time translation symmetry is visible only at wavelengths comparable to the lattice spacing, and it is responsible for transmuting ingoing high Killing frequency modes into low frequency outgoing modes.

  11. Fishing in Black Holes

    E-Print Network [OSTI]

    A. Brotas

    2006-09-01T23:59:59.000Z

    The coordinate system $(\\bar{x},\\bar{t})$ defined by $r = 2m + K\\bar{x}- c K \\bar{t}$ and $t=\\bar{x}/cK - 1 /cK \\int_{r_a}^r (1- 2m/r + K^2)^{1/2} (1 - 2m/r)^{-1}dr$ allow us to write the Schwarzschild metric in the form: \\[ds^2=c^2 d\\bar{t}^2 + (W^2/K^2 - 2W/K) d\\bar{x}^2 + 2c (1 + W/K) d\\bar{x}d\\bar{t} - r^2 (d\\theta^2 + cos^2\\theta d\\phi^2)\\] with $W=(1 - 2m/r + K^2)^{1/2}$, in which the coefficients' pathologies are moved to $r_K = 2m/(1+K^2)$. This new coordinate system is used to study the entrance into a black hole of a rigid line (a line in which the shock waves propagate with velocity c).

  12. Red-Black Trees 1 2004 Goodrich, Tamassia Red-Black Trees

    E-Print Network [OSTI]

    Alechina, Natasha

    Red-Black Trees 1© 2004 Goodrich, Tamassia Red-Black Trees 6 3 8 4 v z #12;Red-Black Trees 2© 2004 Goodrich, Tamassia From (2,4) to Red-Black Trees A red-black tree is a representation of a (2,4) tree by means of a binary tree whose nodes are colored red or black In comparison with its associated (2,4) tree

  13. Kraft black liquor delivery systems

    SciTech Connect (OSTI)

    Adams, T.N.; Empie, H.L.; Obuskovic, N.; Spielbauer, T.M.

    1990-02-01T23:59:59.000Z

    Improvement of spray nozzles for black liquor injection into kraft recovery furnaces is expected to result from obtaining a controlled, well-defined droplet size distribution. Work this year has centered on defining the capabilities of commercial black liquor nozzles currently in use. Considerations of the observed mechanism of droplet formation suggest a major revision is needed in the theory of how droplets form from these nozzles. High resolution, high sensitivity video has been shown to be superior to flash x-ray as a technique for measuring the droplet size distribution as well as the formation history. An environmentally sound spray facility capable of spraying black liquor at temperatures up to normal firing conditions is being constructed before data acquisition continues. Preliminary correlations have been developed between liquor properties, nozzle design, and droplet size. Three aspects of nozzle design have been investigated: droplet size distribution, fluid sheet thickness, and flow and pressure drop characteristics. The standard deviation about the median droplet size for black liquor is nearly the same as the for a wide variety of other fluids and nozzle types. Preliminary correlation for fluid sheet thickness on the plate of a splashplate nozzle show the strong similarities of black liquor to other fluids. The flow and pressure drop characteristic of black liquor nozzle, follow a simple two-term relationship similar to other flow devices. This means that in routine mill operation of black liquor nozzles only the fluid acceleration in the nozzle is important, viscous losses are quiet small. 21 refs., 53 figs., 10 tabs.

  14. Kry of the Warrior Issue 1

    E-Print Network [OSTI]

    -Juriss 82nd KRAF $ $ \\ $\\t\\\\$ fi ror Alf (82nd) personnel FROM: Admiral, Kaul Epetal Juriss SUBJECT: Uniforms/Battle sashes/weapons A1-I personnel not of command rank should wear a red sash from left shoulder to right side of the i"/aist. upper part...

  15. Warrior Girl Corporation | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia:FAQ < RAPID Jump to:Seadov PtyInformationSEDS dataIndiana: Energy

  16. Energy on black hole spacetimes

    E-Print Network [OSTI]

    Alejandro Corichi

    2012-07-18T23:59:59.000Z

    We consider the issue of defining energy for test particles on a background black hole spacetime. We revisit the different notions of energy as defined by different observers. The existence of a time-like isometry allows for the notion of a total conserved energy to be well defined, and subsequently the notion of a gravitational potential energy is also meaningful. We then consider the situation in which the test particle is adsorbed by the black hole, and analyze the energetics in detail. In particular, we show that the notion of horizon energy es defined by the isolated horizons formalism provides a satisfactory notion of energy compatible with the particle's conserved energy. As another example, we comment a recent proposal to define energy of the black hole as seen by an observer at rest. This account is intended to be pedagogical and is aimed at the level of and as a complement to the standard textbooks on the subject.

  17. Call for Papers and Panels Unleashing the Black Erotic

    E-Print Network [OSTI]

    Kunkle, Tom

    and the Hypersexuality of Black Women Alternative Modes of Black Love and Family The Politics and Economics of Porn

  18. Black Hills Energy- Solar Power Program

    Broader source: Energy.gov [DOE]

    Black Hills Energy has a performance-based incentive (PBI) for photovoltaic (PV) systems up to 100 kilowatts (kW) in capacity. In exchange for these incentives, Black Hills Energy earns the right...

  19. Black Literary Suite: Kansas Authors Edition

    E-Print Network [OSTI]

    Wiggins, Meredith Joan

    2015-03-04T23:59:59.000Z

    authors were born or lived in the Sunflower State, and their work often reflects their time in Kansas. This Black Literary Suite exhibit highlights four important black writersLangston Hughes, Gwendolyn Brooks, Frank Marshall Davis, and Kevin Young...

  20. Black brane entropy and hydrodynamics

    SciTech Connect (OSTI)

    Booth, Ivan; Heller, Michal P.; Spalinski, Michal [Department of Mathematics and Statistics, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, A1C 5S7 (Canada); Instituut voor Theoretische Fysica, Universiteit van Amsterdam, Science Park 904, 1090 GL Amsterdam (Netherlands); Soltan Institute for Nuclear Studies, Hoza 69, 00-681 Warsaw (Poland) and Physics Department, University of Bialystok, 15-424 Bialystok (Poland)

    2011-03-15T23:59:59.000Z

    Recent advances in holography have led to the formulation of fluid-gravity duality, a remarkable connection between the hydrodynamics of certain strongly coupled media and dynamics of higher dimensional black holes. This paper introduces a correspondence between phenomenologically defined entropy currents in relativistic hydrodynamics and 'generalized horizons' of near-equilibrium black objects in a dual gravitational description. A general formula is given, expressing the divergence of the entropy current in terms of geometric objects which appear naturally in the gravity dual geometry. The proposed definition is explicitly covariant with respect to boundary diffeomorphisms and reproduces known results when evaluated for the event horizon.

  1. Hawking Emission and Black Hole Thermodynamics

    E-Print Network [OSTI]

    Don N. Page

    2006-12-18T23:59:59.000Z

    A brief review of Hawking radiation and black hole thermodynamics is given, based largely upon hep-th/0409024.

  2. On the nature of black hole entropy

    E-Print Network [OSTI]

    Ted Jacobson

    2000-01-13T23:59:59.000Z

    I argue that black hole entropy counts only those states of a black hole that can influence the outside, and attempt (with only partial success) to defend this claim against various objections, all but one coming from string theory. Implications for the nature of the Bekenstein bound are discussed, and in particular the case for a holographic principle is challenged. Finally, a generalization of black hole thermodynamics to "partial event horizons" in general spacetimes without black holes is proposed.

  3. 6, 34193463, 2006 Black carbon or

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    ACPD 6, 3419­3463, 2006 Black carbon or brown carbon M. O. Andreae and A. Gelencs´er Title Page Chemistry and Physics Discussions Black carbon or brown carbon? The nature of light-absorbing carbonaceous;ACPD 6, 3419­3463, 2006 Black carbon or brown carbon M. O. Andreae and A. Gelencs´er Title Page

  4. White holes and eternal black holes

    E-Print Network [OSTI]

    Stephen D. H. Hsu

    2011-11-16T23:59:59.000Z

    We investigate isolated white holes surrounded by vacuum, which correspond to the time reversal of eternal black holes that do not evaporate. We show that isolated white holes produce quasi- thermal Hawking radiation. The time reversal of this radiation, incident on a black hole precursor, constitutes a special preparation that will cause the black hole to become eternal.

  5. Conservation Assessment for Bloodroot in the Black

    E-Print Network [OSTI]

    Conservation Assessment for Bloodroot in the Black Hills National Forest, South Dakota and Wyoming Forest Service Rocky Mountain Region Black Hills National Forest Custer, South Dakota April 2003 #12;Species Assessment of Bloodroot in the Black Hills National Forest, South Dakota and Wyoming J. Hope

  6. Absorption cross section in Lifshitz black hole

    E-Print Network [OSTI]

    Taeyoon Moon; Yun Soo Myung

    2012-10-05T23:59:59.000Z

    We derive the absorption cross section of a minimally coupled scalar in the Lifshitz black hole obtained from the new massive gravity. The absorption cross section reduces to the horizon area in the low energy and massless limit of s-wave mode propagation, indicating that the Lifshitz black hole also satisfies the universality of low energy absorption cross section for black holes.

  7. Donald Byrne (white) vs. Robert James "Bobby" Fischer (black) 1956 White Black

    E-Print Network [OSTI]

    Zirbel, Craig L.

    Donald Byrne (white) vs. Robert James "Bobby" Fischer (black) 1956 White Black 1. Nf3 Nf6 comments here are called "annotation" 2. c4 g6 3. Nc3 Bg7 black bishop sits on long diagonal 4. d4 0-0 white black threatens the queen 7. Qxc4 c6 8. e4 Nbd7 black's knight on b moves to d7 9. Rd1 Nb6 white's rook

  8. NETL F 451.1-1/1 Categorical Exclusion (CX) Designation Form

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

    CO2 Storage from Coal-fired Power Facilities in the Black Warrior Basin ofAL Conduct seismic survey along Rt.269 corridor, Walker County, Alabama. 11 9 2009 Karen Cohen Digitally...

  9. Black Hole Evaporation as a Nonequilibrium Process

    E-Print Network [OSTI]

    Hiromi Saida

    2008-11-11T23:59:59.000Z

    When a black hole evaporates, there arises a net energy flow from the black hole into its outside environment due to the Hawking radiation and the energy accretion onto black hole. Exactly speaking, due to the net energy flow, the black hole evaporation is a nonequilibrium process. To study details of evaporation process, nonequilibrium effects of the net energy flow should be taken into account. In this article we simplify the situation so that the Hawking radiation consists of non-self-interacting massless matter fields and also the energy accretion onto the black hole consists of the same fields. Then we find that the nonequilibrium nature of black hole evaporation is described by a nonequilibrium state of that field, and we formulate nonequilibrium thermodynamics of non-self-interacting massless fields. By applying it to black hole evaporation, followings are shown: (1) Nonequilibrium effects of the energy flow tends to accelerate the black hole evaporation, and, consequently, a specific nonequilibrium phenomenon of semi-classical black hole evaporation is suggested. Furthermore a suggestion about the end state of quantum size black hole evaporation is proposed in the context of information loss paradox. (2) Negative heat capacity of black hole is the physical essence of the generalized second law of black hole thermodynamics, and self-entropy production inside the matter around black hole is not necessary to ensure the generalized second law. Furthermore a lower bound for total entropy at the end of black hole evaporation is given. A relation of the lower bound with the so-called covariant entropy bound conjecture is interesting but left as an open issue.

  10. BSW process of the slowly evaporating charged black hole

    E-Print Network [OSTI]

    Liancheng Wang; Feng He; Xiangyun Fu

    2015-02-09T23:59:59.000Z

    In this paper, we study the BSW process of the slowly evaporating charged black hole. It can be found that the BSW process will also arise near black hole horizon when the evaporation of charged black hole is very slow. But now the background black hole does not have to be an extremal black hole, and it will be approximately an extremal black hole unless it is nearly a huge stationary black hole.

  11. Origin of black string instability

    SciTech Connect (OSTI)

    Kudoh, Hideaki [Department of Physics, University of Tokyo, Tokyo 113-0033 (Japan)

    2006-05-15T23:59:59.000Z

    It is argued that many nonextremal black branes exhibit a classical Gregory-Laflamme (GL) instability. Why does the universal instability exist? To find an answer to this question and explore other possible instabilities, we study stability of black strings for all possible types of gravitational perturbation. The perturbations are classified into tensor-, vector-, and scalar-types, according to their behavior on the spherical section of the background metric. The vector and scalar perturbations have exceptional multipole moments, and we have paid particular attention to them. It is shown that for each type of perturbations there is no normalizable negative (unstable) modes, apart from the exceptional mode known as s-wave perturbation which is exactly the GL mode. We discuss the origin of instability and comment on the implication for the correlated-stability conjecture.

  12. Accelerating and rotating black holes

    E-Print Network [OSTI]

    J. B. Griffiths; J. Podolsky

    2005-07-06T23:59:59.000Z

    An exact solution of Einstein's equations which represents a pair of accelerating and rotating black holes (a generalised form of the spinning C-metric) is presented. The starting point is a form of the Plebanski-Demianski metric which, in addition to the usual parameters, explicitly includes parameters which describe the acceleration and angular velocity of the sources. This is transformed to a form which explicitly contains the known special cases for either rotating or accelerating black holes. Electromagnetic charges and a NUT parameter are included, the relation between the NUT parameter $l$ and the Plebanski-Demianski parameter $n$ is given, and the physical meaning of all parameters is clarified. The possibility of finding an accelerating NUT solution is also discussed.

  13. Charged spinning black holes as particle accelerators

    SciTech Connect (OSTI)

    Wei Shaowen; Liu Yuxiao; Guo Heng; Fu Chune [Institute of Theoretical Physics, Lanzhou University, Lanzhou 730000 (China)

    2010-11-15T23:59:59.000Z

    It has recently been pointed out that the spinning Kerr black hole with maximal spin could act as a particle collider with arbitrarily high center-of-mass energy. In this paper, we will extend the result to the charged spinning black hole, the Kerr-Newman black hole. The center-of-mass energy of collision for two uncharged particles falling freely from rest at infinity depends not only on the spin a but also on the charge Q of the black hole. We find that an unlimited center-of-mass energy can be approached with the conditions: (1) the collision takes place at the horizon of an extremal black hole; (2) one of the colliding particles has critical angular momentum; (3) the spin a of the extremal black hole satisfies (1/{radical}(3)){<=}(a/M){<=}1, where M is the mass of the Kerr-Newman black hole. The third condition implies that to obtain an arbitrarily high energy, the extremal Kerr-Newman black hole must have a large value of spin, which is a significant difference between the Kerr and Kerr-Newman black holes. Furthermore, we also show that, for a near-extremal black hole, there always exists a finite upper bound for center-of-mass energy, which decreases with the increase of the charge Q.

  14. Dave Kaminsky Charles L. Black

    E-Print Network [OSTI]

    Edwin D. McKay Thomas L. McNeely Jean C. Persons Neysa P. Pickens Armant C. Touchy Jack S. Zoller 19511935 $50.00 Dave Kaminsky 1938 $200.00 Charles L. Black 1940 $50.00 Harold S. Miropol 1941 $67. Tennison Ben Thompson 1945 $250.00 Paul Finkelstein Harold J. Jacobs Lawrence Kahn 1946 $2,250.00 David W

  15. Black Hole Thermodynamics and Electromagnetism

    E-Print Network [OSTI]

    Burra G. Sidharth

    2005-07-15T23:59:59.000Z

    We show a strong parallel between the Hawking, Beckenstein black hole Thermodynamics and electromagnetism: When the gravitational coupling constant transform into the electromagnetic coupling constant, the Schwarzchild radius, the Beckenstein temperature, the Beckenstein decay time and the Planck mass transform to respectively the Compton wavelength, the Hagedorn temperature, the Compton time and a typical elementary particle mass. The reasons underlying this parallalism are then discussed in detail.

  16. ARM - Measurement - Black carbon concentration

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc Documentation RUC : XDCResearch Related InformationAcid RainTheimagegovMeasurementsBlack carbon

  17. Red-Black Trees 11/26/2007 11:09 AM Red-Black Trees 1 2004 Goodrich, Tamassia

    E-Print Network [OSTI]

    Alechina, Natasha

    Red-Black Trees 11/26/2007 11:09 AM 1 Red-Black Trees 1© 2004 Goodrich, Tamassia Red-Black Trees 6 3 8 4 v z Red-Black Trees 2© 2004 Goodrich, Tamassia From (2,4) to Red-Black Trees A red-black tree is a representation of a (2,4) tree by means of a binary tree whose nodes are colored red or black In comparison

  18. Red-Black Trees 11/11/2004 10:02 AM Red-Black Trees 1 2004 Goodrich, Tamassia

    E-Print Network [OSTI]

    Alechina, Natasha

    Red-Black Trees 11/11/2004 10:02 AM 1 Red-Black Trees 1© 2004 Goodrich, Tamassia Red-Black Trees 6 3 8 4 v z Red-Black Trees 2© 2004 Goodrich, Tamassia From (2,4) to Red-Black Trees A red-black tree is a representation of a (2,4) tree by means of a binary tree whose nodes are colored red or black In comparison

  19. Entanglement entropy of black holes

    E-Print Network [OSTI]

    Sergey N. Solodukhin

    2011-04-19T23:59:59.000Z

    The entanglement entropy is a fundamental quantity which characterizes the correlations between sub-systems in a larger quantum-mechanical system. For two sub-systems separated by a surface the entanglement entropy is proportional to the area of the surface and depends on the UV cutoff which regulates the short-distance correlations. The geometrical nature of the entanglement entropy calculation is particularly intriguing when applied to black holes when the entangling surface is the black hole horizon. I review a variety of aspects of this calculation: the useful mathematical tools such as the geometry of spaces with conical singularities and the heat kernel method, the UV divergences in the entropy and their renormalization, the logarithmic terms in the entanglement entropy in 4 and 6 dimensions and their relation to the conformal anomalies. The focus in the review is on the systematic use of the conical singularity method. The relations to other known approaches such as 't Hooft's brick wall model and the Euclidean path integral in the optical metric are discussed in detail. The puzzling behavior of the entanglement entropy due to fields which non-minimally couple to gravity is emphasized. The holographic description of the entanglement entropy of the black hole horizon is illustrated on the two- and four-dimensional examples. Finally, I examine the possibility to interpret the Bekenstein-Hawking entropy entirely as the entanglement entropy.

  20. Quantum Geometry and Black Holes

    E-Print Network [OSTI]

    G., J Fernando Barbero

    2015-01-01T23:59:59.000Z

    We present an overall picture of the advances in the description of black hole physics from the perspective of loop quantum gravity. After an introduction that discusses the main conceptual issues we present some details about the classical and quantum geometry of isolated horizons and their quantum geometry and then use this scheme to give a natural definition of the entropy of black holes. The entropy computations can be neatly expressed in the form of combinatorial problems solvable with the help of methods based on number theory and the use of generating functions. The recovery of the Bekenstein-Hawking law and corrections to it is explained in some detail. After this, due attention is paid to the discussion of semiclassical issues. An important point in this respect is the proper interpretation of the horizon area as the energy that should appear in the statistical-mechanical treatment of the black hole model presented here. The chapter ends with a comparison between the microscopic and semiclassical app...

  1. Combustion properties of Kraft Black Liquors

    SciTech Connect (OSTI)

    Frederick, W.J. Jr.; Hupa, M. (Aabo Akademi, Turku (Finland))

    1993-04-01T23:59:59.000Z

    In a previous study of the phenomena involved in the combustion of black liquor droplets a numerical model was developed. The model required certain black liquor specific combustion information which was then not currently available, and additional data were needed for evaluating the model. The overall objectives of the project reported here was to provide experimental data on key aspects of black liquor combustion, to interpret the data, and to put it into a form which would be useful for computational models for recovery boilers. The specific topics to be investigated were the volatiles and char carbon yields from pyrolysis of single black liquor droplets; a criterion for the onset of devolatilization and the accompanying rapid swelling; and the surface temperature of black liquor droplets during pyrolysis, combustion, and gasification. Additional information on the swelling characteristics of black liquor droplets was also obtained as part of the experiments conducted.

  2. Dirac Quasinormal modes of MSW black holes

    E-Print Network [OSTI]

    Sebastian, Saneesh

    2014-01-01T23:59:59.000Z

    In this paper we study the Dirac quasinormal modes of an uncharged 2 + 1 black hole proposed by Mandal et. al and referred to as MSW black hole in this work. The quasi- normal mode is studied using WKB approximation method. The study shows that the imaginary part of quasinormal frequencies increases indicating that the oscillations are damping and hence the black hole is stable against Dirac perturbations.

  3. Dirac Quasinormal modes of MSW black holes

    E-Print Network [OSTI]

    Saneesh Sebastian; V. C. Kuriakose

    2014-01-15T23:59:59.000Z

    In this paper we study the Dirac quasinormal modes of an uncharged 2 + 1 black hole proposed by Mandal et. al and referred to as MSW black hole in this work. The quasi- normal mode is studied using WKB approximation method. The study shows that the imaginary part of quasinormal frequencies increases indicating that the oscillations are damping and hence the black hole is stable against Dirac perturbations.

  4. Black hole entropy: inside or out?

    E-Print Network [OSTI]

    Ted Jacobson; Donald Marolf; Carlo Rovelli

    2005-01-14T23:59:59.000Z

    A trialogue. Ted, Don, and Carlo consider the nature of black hole entropy. Ted and Carlo support the idea that this entropy measures in some sense ``the number of black hole microstates that can communicate with the outside world.'' Don is critical of this approach, and discussion ensues, focusing on the question of whether the first law of black hole thermodynamics can be understood from a statistical mechanics point of view.

  5. Spinning Black Holes as Particle Accelerators

    E-Print Network [OSTI]

    Ted Jacobson; Thomas P. Sotiriou

    2010-01-21T23:59:59.000Z

    It has recently been pointed out that particles falling freely from rest at infinity outside a Kerr black hole can in principle collide with arbitrarily high center of mass energy in the limiting case of maximal black hole spin. Here we aim to elucidate the mechanism for this fascinating result, and to point out its practical limitations, which imply that ultra-energetic collisions cannot occur near black holes in nature.

  6. Probing the Constituent Structure of Black Holes

    E-Print Network [OSTI]

    Lukas Gruending; Stefan Hofmann; Sophia Mller; Tehseen Rug

    2014-12-12T23:59:59.000Z

    We calculate the cross section for scattering processes between graviton emitters on the near side of a Schwarzschild surface and absorbers on its far side, that is black hole constituents. We show that these scatterings allow to directly extract structural observables such as the momentum distribution of black hole constituents. For this we employ a quantum bound state description originally developed in quantum chromodynamics and recently applied to general relativity that allows to consider black holes in a relativistic Hartree like framework.

  7. Remarks on Renormalization of Black Hole Entropy

    E-Print Network [OSTI]

    Sang Pyo Kim; Sung Ku Kim; Kwang-Sup Soh; Jae Hyung Yee

    1996-07-07T23:59:59.000Z

    We elaborate the renormalization process of entropy of a nonextremal and an extremal Reissner-Nordstr\\"{o}m black hole by using the Pauli-Villars regularization method, in which the regulator fields obey either the Bose-Einstein or Fermi-Dirac distribution depending on their spin-statistics. The black hole entropy involves only two renormalization constants. We also discuss the entropy and temperature of the extremal black hole.

  8. Absorption cross section of RN black hole

    E-Print Network [OSTI]

    Sini R.; V. C. Kuriakose

    2007-08-23T23:59:59.000Z

    The behavior of a charged scalar field in the RN black hole space time is studied using WKB approximation. In the present work it is assumed that matter waves can get reflected from the event horizon. Using this effect, the Hawking temperature and the absorption cross section for RN black hole placed in a charged scalar field are calculated. The absorption cross section $\\sigma _{abs}$ is found to be inversely proportional to square of the Hawking temperature of the black hole.

  9. Black holes with massive graviton hair

    E-Print Network [OSTI]

    Richard Brito; Vitor Cardoso; Paolo Pani

    2013-09-03T23:59:59.000Z

    No-hair theorems exclude the existence of nontrivial scalar and massive vector hair outside four-dimensional, static, asymptotically flat black-hole spacetimes. We show, by explicitly building nonlinear solutions, that black holes can support massive graviton hair in theories of massive gravity. These hairy solutions are, most likely, the generic end state of the recently discovered monopole instability of Schwarzschild black holes in massive graviton theories.

  10. Red-black Trees To know what a red-black tree is (10.1).

    E-Print Network [OSTI]

    Liang, Y. Daniel

    809 CHAPTER 10 Red-black Trees Objectives · To know what a red-black tree is (§10.1). · To convert a red-black tree to a 2-4 tree and vice versa (§10.2). · To design the RBTree class that extends the BinaryTree class (§10.3). · To insert an element in a red-black tree and resolve the double red problem

  11. Destroying black holes with test bodies

    E-Print Network [OSTI]

    Ted Jacobson; Thomas P. Sotiriou

    2010-06-09T23:59:59.000Z

    If a black hole can accrete a body whose spin or charge would send the black hole parameters over the extremal limit, then a naked singularity would presumably form, in violation of the cosmic censorship conjecture. We review some previous results on testing cosmic censorship in this way using the test body approximation, focusing mostly on the case of neutral black holes. Under certain conditions a black hole can indeed be over-spun or over-charged in this approximation, hence radiative and self-force effects must be taken into account to further test cosmic censorship.

  12. Black Liquor Research Program symposium: proceedings

    SciTech Connect (OSTI)

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

    1985-03-01T23:59:59.000Z

    In the paper pulp industry's recovery boilers, black liquor is sprayed in through nozzle guns near the top of the furnace. This report includes eight papers. (DLC)

  13. Black Hills Power- Commercial Energy Efficiency Programs

    Broader source: Energy.gov [DOE]

    Black Hills Power provides rebates for its commercial customers who install energy efficient heat pumps, motors, variable frequency drives, lighting, and water heaters. Custom rebates for approved...

  14. Black Hills Power- Residential Customer Rebate Program

    Broader source: Energy.gov [DOE]

    Black Hills Power offers cash rebates to residential customers who purchase and install energy efficient equipment in their homes. Incentives exist for water heaters, demand control units, air...

  15. Lower Dimensional Black Holes: Inside and Out

    E-Print Network [OSTI]

    R. B. Mann

    1995-01-27T23:59:59.000Z

    I survey the physics of black holes in two and three spacetime dimensions, with special attention given to an understanding of their exterior and interior properties.

  16. International House Collection / William Black (collector)

    E-Print Network [OSTI]

    Handy, Todd C.

    International House Collection / William Black (collector) Revised by Erwin Wodarczak (2010 (collector). 1950-1953. 45 p. of textual records. Biographical Sketch Born in London, England, William

  17. Black Holes: from Speculations to Observations

    E-Print Network [OSTI]

    Thomas W. Baumgarte

    2006-04-13T23:59:59.000Z

    This paper provides a brief review of the history of our understanding and knowledge of black holes. Starting with early speculations on ``dark stars'' I discuss the Schwarzschild "black hole" solution to Einstein's field equations and the development of its interpretation from "physically meaningless" to describing the perhaps most exotic and yet "most perfect" macroscopic object in the universe. I describe different astrophysical black hole populations and discuss some of their observational evidence. Finally I close by speculating about future observations of black holes with the new generation of gravitational wave detectors.

  18. Superconducting Hair on Charged Black String Background

    E-Print Network [OSTI]

    Lukasz Nakonieczny; Marek Rogatko

    2012-01-25T23:59:59.000Z

    Behaviour of Dirac fermions in the background of a charged black string penetrated by an Abelian Higgs vortex is elaborated. One finds the evidence that the system under consideration can support fermion fields acting like a superconducting cosmic string in the sence that a nontrivial Dirac fermion field can be carried by the system in question. The case of nonextremal and extremal black string vortex systems were considered. The influence of electric and Higgs charge, the winding number and the fermion mass on the fermion localization near the black string event horizon was studied. It turned out that the extreme charged black string expelled fermion fields more violently comparing to the nonextremal one.

  19. A new spin on black hole hair

    E-Print Network [OSTI]

    Herdeiro, Carlos A R

    2014-01-01T23:59:59.000Z

    We show that scalar hair can be added to rotating, vacuum black holes of general relativity. These hairy black holes (HBHs) clarify a lingering question concerning gravitational solitons: if a black hole can be added at the centre of a boson star, as it typically can for other solitons. We argue that it can, but only if it is spinning. The existence of such HBHs is related to the Kerr superradiant instability triggered by a massive scalar field. This connection leads to the following conjecture: a (hairless) black hole which is afflicted by the superradiant instability of a given field must allow hairy generalizations with that field.

  20. Black Swans, Dragons-Kings and Prediction Black Swan (Cygnus atratus)

    E-Print Network [OSTI]

    Black Swans, Dragons-Kings and Prediction Black Swan (Cygnus atratus) www.er.ethz.ch Didier hurricanes normalized to 1995 dollars by inflation, personal property increases and coastal county population;12 2008 FINANCIAL CRISIS #12;Crises are not but "Dragon-kings" Dragon-king hypothesis #12;Black Swan story

  1. National Society of Black EngineersNational Society of Black Engineers Columbia University Chapter

    E-Print Network [OSTI]

    Hone, James

    National Society of Black EngineersNational Society of Black Engineers Columbia University Chapter #12;Columbia University Greetings NSBE Family and Friends! My name is Ken Yearwood, the 2008-2009 Columbia University NSBE (National Society of Black Engineers) Chapter President. On behalf of the Columbia

  2. Deep Frames, White Men's Discourse, and Black Female Bodies

    E-Print Network [OSTI]

    Slatton, Brittany C.

    2012-02-14T23:59:59.000Z

    In this qualitative study, I examine the persistent trend of black women as an excluded relationship partner for white men. Integral to understanding the exclusion of black women as relationship partners is the construction of black female bodies...

  3. Causticizing for Black Liquor Gasifiers

    SciTech Connect (OSTI)

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

    2009-01-07T23:59:59.000Z

    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

    2005-03-01T23:59:59.000Z

    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-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. This report covers Task 1.3, Simulative corrosion of candidate materials developed by refractory producers and in the laboratory based on the results of Task 1.1 and Task 1.2. Refractories provided by in-kind sponsors were tested by cup testing, density/porosity determinations, chemical analysis and microscopy. The best performing materials in the cup testing were fused cast materials. However, 2 castables appear to outperforming any of the previously tested materials and may perform better than the fused cast materials in operation. The basis of the high performance of these materials is the low open porosity and permeability to black liquor smelt.

  5. Congressional Black Caucus Foundation, Inc. Meet/Match Procurement...

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

    Congressional Black Caucus Foundation, Inc. MeetMatch Procurement Forum Congressional Black Caucus Foundation, Inc. MeetMatch Procurement Forum Presented by Congresswoman Sheila...

  6. White House Initiative on Historically Black Colleges and Universities...

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

    White House Initiative on Historically Black Colleges and Universities White House Initiative on Historically Black Colleges and Universities How WHI-HBCU are ran White House...

  7. Austin E. Quigley Black Box Theater Proposal Form

    E-Print Network [OSTI]

    Hone, James

    -1- Austin E. Quigley Black Box Theater Proposal Form Sponsoring Organization indicate that you have read the Austin E. Quigley Black Box Theatre Policy and Procedure Guidelines

  8. Energy conservation for dynamical black holes

    E-Print Network [OSTI]

    Sean A. Hayward

    2004-08-03T23:59:59.000Z

    An energy conservation law is described, expressing the increase in mass-energy of a general black hole in terms of the energy densities of the infalling matter and gravitational radiation. For a growing black hole, this first law of black-hole dynamics is equivalent to an equation of Ashtekar & Krishnan, but the new integral and differential forms are regular in the limit where the black hole ceases to grow. An effective gravitational-radiation energy tensor is obtained, providing measures of both ingoing and outgoing, transverse and longitudinal gravitational radiation on and near a black hole. Corresponding energy-tensor forms of the first law involve a preferred time vector which plays the role for dynamical black holes which the stationary Killing vector plays for stationary black holes. Identifying an energy flux, vanishing if and only if the horizon is null, allows a division into energy-supply and work terms, as in the first law of thermodynamics. The energy supply can be expressed in terms of area increase and a newly defined surface gravity, yielding a Gibbs-like equation, with a similar form to the so-called first law for stationary black holes.

  9. Quantum Entropy of Charged Rotating Black Holes

    E-Print Network [OSTI]

    R. B. Mann

    1996-07-10T23:59:59.000Z

    I discuss a method for obtaining the one-loop quantum corrections to the tree-level entropy for a charged Kerr black hole. Divergences which appear can be removed by renormalization of couplings in the tree-level gravitational action in a manner similar to that for a static black hole.

  10. Black holes cannot support conformal scalar hair

    E-Print Network [OSTI]

    T. Zannias

    1994-09-14T23:59:59.000Z

    It is shown that the only static asymptotically flat non-extrema black hole solution of the Einstein-conformally invariant scalar field equations having the scalar field bounded on the horizon, is the Schwarzschild one. Thus black holes cannot be endowed with conformal scalar hair of finite length.

  11. The Kansas Black Bass Tournament Monitoring Program

    E-Print Network [OSTI]

    The Kansas Black Bass (Micropterus spp.) Tournament Monitoring Program was begun by the Kansas Fish and Game program of the Kansas Fish and Game Commission avoids both of these prob- lems. The Kansas Black Bass annually to each of the bass clubs in Kansas before the bulk of fishing begins, and clubs are asked

  12. Topological Black Holes in Quantum Gravity

    E-Print Network [OSTI]

    J. Kowalski-Glikman; D. Nowak-Szczepaniak

    2000-07-31T23:59:59.000Z

    We derive the black hole solutions with horizons of non-trivial topology and investigate their properties in the framework of an approach to quantum gravity being an extension of Bohm's formulation of quantum mechanics. The solutions we found tend asymptotically (for large $r$) to topological black holes. We also analyze the thermodynamics of these space-times.

  13. Cooking with Black-Eyed Peas

    E-Print Network [OSTI]

    Anding, Jenna

    2008-12-09T23:59:59.000Z

    the most protein from the peas, serve them with grain foods such as corn, rice or wheat. A serving size is ? cup. Uses Use black-eyed peas as a tasty side dish or include it in casseroles, soups, and salads. Black-eyed peas are often packaged in 1- or 2...

  14. Distortion of Schwarzschild-anti-de Sitter black holes to black strings

    E-Print Network [OSTI]

    A. Tomimatsu

    2005-06-25T23:59:59.000Z

    Motivated by the existence of black holes with various topologies in four-dimensional spacetimes with a negative cosmological constant, we study axisymmetric static solutions describing any large distortions of Schwarzschild-anti-de Sitter black holes parametrized by the mass $m$. Under the approximation such that $m$ is much larger than the anti-de Sitter radius, it is found that a cylindrically symmetric black string is obtained as a special limit of distorted spherical black holes. Such a prolonged distortion of the event horizon connecting a Schwarzschild-anti-de Sitter black hole to a black string is allowed without violating both the usual black hole thermodynamics and the hoop conjecture for the horizon circumference.

  15. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    SciTech Connect (OSTI)

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

    2004-10-01T23:59:59.000Z

    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-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. Material development will be divided into 2 tasks: Task 1, Development and property determinations of improved and existing refractory systems for black liquor containment. Refractory systems of interest include magnesium aluminate and barium aluminate for binder materials, both dry and hydratable, and materials with high alumina contents, 85-95 wt%, aluminum oxide, 5.0-15.0 wt%, and BaO, SrO, CaO, ZrO{sub 2} and SiC. Task 2, Finite element analysis of heat flow and thermal stress/strain in the refractory lining and steel shell of existing and proposed vessel designs. Stress and strain due to thermal and chemical expansion has been observed to be detrimental to the lifespan of existing black liquor gasifiers. The thermal and chemical strain as well as corrosion rates must be accounted for in order to predict the lifetime of the gasifier containment materials.

  16. Refractory for Black Liquor Gasifiers

    SciTech Connect (OSTI)

    William L. Headrick; Musa Karakus; Alireza Rezaie

    2004-03-30T23:59:59.000Z

    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-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. Material development will be divided into 2 tasks: Task 1, Development and property determinations of improved and existing refractory systems for black liquor containment. Refractory systems of interest include magnesium aluminate and barium aluminate for binder materials, both dry and hydratable, and materials with high alumina contents, 85-95 wt%, aluminum oxide, 5.0-15.0 wt%, and BaO, SrO, CaO, ZrO2 and SiC. Task 2, Finite element analysis of heat flow and thermal stress/strain in the refractory lining and steel shell of existing and proposed vessel designs. Stress and strain due to thermal and chemical expansion has been observed to be detrimental to the lifespan of existing black liquor gasifiers. The thermal and chemical strain as well as corrosion rates must be accounted for in order to predict the lifetime of the gasifier containment materials.

  17. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    SciTech Connect (OSTI)

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

    2004-07-01T23:59:59.000Z

    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-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. Material development will be divided into 2 tasks: Task 1, Development and property determinations of improved and existing refractory systems for black liquor containment. Refractory systems of interest include magnesium aluminate and barium aluminate for binder materials, both dry and hydratable, and materials with high alumina contents, 85-95 wt%, aluminum oxide, 5.0-15.0 wt%, and BaO, SrO, CaO, ZrO{sub 2} and SiC. Task 2, Finite element analysis of heat flow and thermal stress/strain in the refractory lining and steel shell of existing and proposed vessel designs. Stress and strain due to thermal and chemical expansion has been observed to be detrimental to the lifespan of existing black liquor gasifiers. The thermal and chemical strain as well as corrosion rates must be accounted for in order to predict the lifetime of the gasifier containment materials.

  18. Refractory for Black Liquor Gasifiers

    SciTech Connect (OSTI)

    William L. Headrick Jr; Musa Karakus; Xiaoting Liang

    2005-10-01T23:59:59.000Z

    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 were functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. Material development were divided into 2 tasks: Task 1, Development and property determinations of improved and existing refractory systems for black liquor containment. Refractory systems of interest include magnesium aluminate and barium aluminate for binder materials, both dry and hydratable, and materials with high alumina contents, 85-95 wt%, aluminum oxide, 5.0-15.0 wt%, and BaO, SrO, CaO, ZrO{sub 2} and SiC. Task 2, Finite element analysis of heat flow and thermal stress/strain in the refractory lining and steel shell of existing and proposed vessel designs. Stress and strain due to thermal and chemical expansion has been observed to be detrimental to the lifespan of existing black liquor gasifiers. The thermal and chemical strain as well as corrosion rates must be accounted for in order to predict the lifetime of the gasifier containment materials.

  19. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    SciTech Connect (OSTI)

    William L. Headrick Jr.; Alireza Rezaie

    2004-04-01T23:59:59.000Z

    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 (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-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. Material development will be divided into 2 tasks: Task 1, Development and property determinations of improved and existing refractory systems for black liquor containment. Refractory systems of interest include magnesium aluminate and barium aluminate spinels for binder materials, both dry and hydratable, and materials with high alumina contents, 85-95 wt%, aluminum oxide, 5.0-15.0 wt%, and BaO, SrO, CaO, ZrO{sub 2} and SiC. Task 2, Finite element analysis of heat flow and thermal stress/strain in the refractory lining and steel shell of existing and proposed vessel designs. Stress and strain due to thermal and chemical expansion has been observed to be detrimental to the lifespan of existing black liquor gasifiers. The thermal and chemical strain as well as corrosion rates must be accounted for in order to predict the lifetime of the gasifier containment materials.

  20. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    SciTech Connect (OSTI)

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

    2005-04-01T23:59:59.000Z

    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-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. Material development will be divided into 2 tasks: Task 1, Development and property determinations of improved and existing refractory systems for black liquor containment. Refractory systems of interest include magnesium aluminate and barium aluminate for binder materials, both dry and hydratable, and materials with high alumina contents, 85-95 wt%, aluminum oxide, 5.0-15.0 wt%, and BaO, SrO, CaO, ZrO{sub 2} and SiC. Task 2, Finite element analysis of heat flow and thermal stress/strain in the refractory lining and steel shell of existing and proposed vessel designs. Stress and strain due to thermal and chemical expansion has been observed to be detrimental to the lifespan of existing black liquor gasifiers. The thermal and chemical strain as well as corrosion rates must be accounted for in order to predict the lifetime of the gasifier containment materials.

  1. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    SciTech Connect (OSTI)

    William L. Headrick Jr; Musa Karakus; Xiaoting Liang

    2005-07-01T23:59:59.000Z

    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-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. Material development will be divided into 2 tasks: Task 1, Development and property determinations of improved and existing refractory systems for black liquor containment. Refractory systems of interest include magnesium aluminate and barium aluminate for binder materials, both dry and hydratable, and materials with high alumina contents, 85-95 wt%, aluminum oxide, 5.0-15.0 wt%, and BaO, SrO, CaO, ZrO{sub 2} and SiC. Task 2, Finite element analysis of heat flow and thermal stress/strain in the refractory lining and steel shell of existing and proposed vessel designs. Stress and strain due to thermal and chemical expansion has been observed to be detrimental to the lifespan of existing black liquor gasifiers. The thermal and chemical strain as well as corrosion rates must be accounted for in order to predict the lifetime of the gasifier containment materials.

  2. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    SciTech Connect (OSTI)

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

    2005-01-01T23:59:59.000Z

    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-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. Material development will be divided into 2 tasks: Task 1, Development and property determinations of improved and existing refractory systems for black liquor containment. Refractory systems of interest include magnesium aluminate and barium aluminate for binder materials, both dry and hydratable, and materials with high alumina contents, 85-95 wt%, aluminum oxide, 5.0-15.0 wt%, and BaO, SrO, CaO, ZrO{sub 2} and SiC. Task 2, Finite element analysis of heat flow and thermal stress/strain in the refractory lining and steel shell of existing and proposed vessel designs. Stress and strain due to thermal and chemical expansion has been observed to be detrimental to the lifespan of existing black liquor gasifiers. The thermal and chemical strain as well as corrosion rates must be accounted for in order to predict the lifetime of the gasifier containment materials.

  3. Refractory for Black Liquor Gasifiers

    SciTech Connect (OSTI)

    William L. Headrick Jr; Alireza Rezaie

    2003-12-01T23:59:59.000Z

    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-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. Material development will be divided into 2 tasks: Task 1, Development and property determinations of improved and existing refractory systems for black liquor containment. Refractory systems of interest include magnesia aluminate and baria aluminate spinels for binder materials, both dry and hydratable, and materials with high alumina contents, 85-95 wt%, aluminum oxide, 5.0-15.0 wt%, and BaO, SrO, CaO, ZrO and SiC. Task 2, Finite element analysis of heat flow and thermal stress/strain in the refractory lining and steel shell of existing and proposed vessel designs. Stress and strain due to thermal and chemical expansion has been observed to be detrimental to the lifespan of existing black liquor gasifiers. The thermal and chemical strain as well as corrosion rates must be accounted for in order to predict the lifetime of the gasifier containment materials.

  4. Refractory for Black Liquor Gasifiers

    SciTech Connect (OSTI)

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

    2005-12-01T23:59:59.000Z

    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 were functionally-graded to give the best combination of thermal, mechanical and physical properties and chemical stability; and are relatively inexpensive, reliable repair materials. Material development was divided into 2 tasks: Task 1 was development and property determinations of improved and existing refractory systems for black liquor containment. Refractory systems of interest include magnesium aluminate and barium aluminate for binder materials, both dry and hydratable, and materials with high alumina contents, 85-95 wt%, aluminum oxide, 5.0-15.0 wt%, and BaO, SrO, CaO, ZrO2 and SiC. Task 2 was finite element analysis of heat flow and thermal stress/strain in the refractory lining and steel shell of existing and proposed vessel designs. Stress and strain due to thermal and chemical expansion has been observed to be detrimental to the lifespan of existing black liquor gasifiers. The thermal and chemical strain as well as corrosion rates must be accounted for in order to predict the lifetime of the gasifier containment materials.

  5. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    SciTech Connect (OSTI)

    William L. Headrick Jr.; Alireza Rezaie

    2003-12-01T23:59:59.000Z

    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-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. Material development will be divided into 2 tasks: Task 1, Development and property determinations of improved and existing refractory systems for black liquor containment. Refractory systems of interest include magnesia aluminate and baria aluminate spinels for binder materials, both dry and hydratable, and materials with high alumina contents, 85-95 wt%, aluminum oxide, 5.0-15.0 wt%, and BaO, SrO, CaO, ZrO and SiC. Task 2, Finite element analysis of heat flow and thermal stress/strain in the refractory lining and steel shell of existing and proposed vessel designs. Stress and strain due to thermal and chemical expansion has been observed to be detrimental to the lifespan of existing black liquor gasifiers. The thermal and chemical strain as well as corrosion rates must be accounted for in order to predict the lifetime of the gasifier containment materials.

  6. Refractory for Black Liquor Gasifiers

    SciTech Connect (OSTI)

    William L. Headrick Jr; Alireza Rezaie

    2003-08-01T23:59:59.000Z

    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-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. Material development will be divided into 2 tasks: Task 1, Development and property determinations of improved and existing refractory systems for black liquor containment. Refractory systems of interest include magnesia aluminate and baria aluminate spinels for binder materials, both dry and hydratable, and materials with high alumina contents, 85-95 wt%, aluminum oxide, 5.0-15.0 wt%, and BaO, SrO, CaO, ZrO and SiC. Task 2, Finite element analysis of heat flow and thermal stress/strain in the refractory lining and steel shell of existing and proposed vessel designs. Stress and strain due to thermal and chemical expansion has been observed to be detrimental to the lifespan of existing black liquor gasifiers. The thermal and chemical strain as well as corrosion rates must be accounted for in order to predict the lifetime of the gasifier containment materials.

  7. Refractory for Black Liquor Gasifiers

    SciTech Connect (OSTI)

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

    2003-03-31T23:59:59.000Z

    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-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. Material development will be divided into 2 tasks: Task 1, Development and property determinations of improved and existing refractory systems for black liquor containment. Refractory systems of interest include magnesia aluminate and baria aluminate spinels for binder materials, both dry and hydratable, and materials with high alumina contents, 85-95 wt%, aluminum oxide, 5.0-15.0 wt%, and BaO, SrO, CaO, ZrO and SiC. Task 2, Finite element analysis of heat flow and thermal stress/strain in the refractory lining and steel shell of existing and proposed vessel designs. Stress and strain due to thermal and chemical expansion has been observed to be detrimental to the lifespan of existing black liquor gasifiers. The thermal and chemical strain as well as corrosion rates must be accounted for in order to predict the lifetime of the gasifier containment materials.

  8. Black hole and holographic dark energy

    E-Print Network [OSTI]

    Yun Soo Myung

    2007-04-11T23:59:59.000Z

    We discuss the connection between black hole and holographic dark energy. We examine the issue of the equation of state (EOS) for holographic energy density as a candidate for the dark energy carefully. This is closely related to the EOS for black hole, because the holographic dark energy comes from the black hole energy density. In order to derive the EOS of a black hole, we may use its dual (quantum) systems. Finally, a regular black hole without the singularity is introduced to describe an accelerating universe inside the cosmological horizon. Inspired by this, we show that the holographic energy density with the cosmological horizon as the IR cutoff leads to the dark energy-dominated universe with $\\omega_{\\rm \\Lambda}=-1$.

  9. Black Hole Thermodynamics Based on Unitary Evolutions

    E-Print Network [OSTI]

    Feng, Yu-Lei

    2015-01-01T23:59:59.000Z

    In this paper, we try to construct black hole thermodynamics based on the fact that, the formation and evaporation of a black hole can be described by quantum unitary evolutions. First, we show that the Bekenstein-Hawking entropy $S_{BH}$ cannot be a Boltzmann or thermal entropy. To confirm this statement, we show that the original black hole's "first law" cannot be treated as the first law of thermodynamics formally, due to some missing metric perturbations caused by matter. Then, by including those (quantum) metric perturbations, we show that the black hole formation and evaporation can be described in a unitary manner effectively, through a quantum channel between the exterior and interior of the event horizon. In this way, the paradoxes of information loss and firewall can be resolved effectively. Finally, we show that black hole thermodynamics can be constructed in an ordinary way, by constructing statistical mechanics.

  10. An electromagnetic black hole made of metamaterials

    E-Print Network [OSTI]

    Cheng, Qiang

    2009-01-01T23:59:59.000Z

    Traditionally, a black hole is a region of space with huge gravitational field in the means of general relativity, which absorbs everything hitting it including the light. In general relativity, the presence of matter-energy densities results in the motion of matter propagating in a curved spacetime1, which is similar to the electromagnetic-wave propagation in a curved space and in an inhomogeneous metamaterial2. Hence one can simulate the black hole using electromagnetic fields and metamaterials. In a recent theoretical work, an optical black hole has been proposed based on metamaterials, in which the numerical simulations showed a highly efficient light absorption3. Here we report the first experimental demonstration of electromagnetic black hole in the microwave frequencies. The proposed black hole is composed of non-resonant and resonant metamaterial structures, which can absorb electromagnetic waves efficiently coming from all directions due to the local control of electromagnetic fields. Hence the elect...

  11. Black holes in Asymptotically Safe Gravity

    E-Print Network [OSTI]

    Saueressig, Frank; D'Odorico, Giulio; Vidotto, Francesca

    2015-01-01T23:59:59.000Z

    Black holes are among the most fascinating objects populating our universe. Their characteristic features, encompassing spacetime singularities, event horizons, and black hole thermodynamics, provide a rich testing ground for quantum gravity ideas. In this note we observe that the renormalization group improved Schwarzschild black holes constructed by Bonanno and Reuter within Weinberg's asymptotic safety program constitute a prototypical example of a Hayward geometry used to model non-singular black holes within quantum gravity phenomenology. Moreover, they share many features of a Planck star: their effective geometry naturally incorporates the one-loop corrections found in the effective field theory framework, their Kretschmann scalar is bounded, and the black hole singularity is replaced by a regular de Sitter patch. The role of the cosmological constant in the renormalization group improvement process is briefly discussed.

  12. Black Hole Superradiance in Dynamical Spacetime

    E-Print Network [OSTI]

    William E. East; Fethi M. Ramazano?lu; Frans Pretorius

    2014-03-14T23:59:59.000Z

    We study the superradiant scattering of gravitational waves by a nearly extremal black hole (dimensionless spin $a=0.99$) by numerically solving the full Einstein field equations, thus including backreaction effects. This allows us to study the dynamics of the black hole as it loses energy and angular momentum during the scattering process. To explore the nonlinear phase of the interaction, we consider gravitational wave packets with initial energies up to $10%$ of the mass of the black hole. We find that as the incident wave energy increases, the amplification of the scattered waves, as well as the energy extraction efficiency from the black hole, is reduced. During the interaction the apparent horizon geometry undergoes sizable nonaxisymmetric oscillations. The largest amplitude excitations occur when the peak frequency of the incident wave packet is above where superradiance occurs, but close to the dominant quasinormal mode frequency of the black hole.

  13. Refractory for Black Liquor Gasifiers

    SciTech Connect (OSTI)

    William L. Headrick Jr; Musa Karakus; Xiaoting Laing

    2005-10-01T23:59:59.000Z

    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-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. This report covers Task 1.4, Industrial Trial of candidate materials developed by refractory producers and in the laboratory based on the results of Task 1.1, 1.2 and 1.3. Refractories provided by in-kind sponsors to industrial installations tested by cup testing, density/porosity determinations, chemical analysis and microscopy. None of the materials produced in this program have been tried in high temperature gasifiers, but the mortar developed Morcocoat SP-P is outperforming other mortars tested at ORNL. MORCO PhosGun M-90-O has shown in laboratory testing to be an acceptable candidate for hot and cold repairs of existing high temperature gasifiers. It may prove to be an acceptable lining material.

  14. Thermodynamics of Dyonic Lifshitz Black Holes

    E-Print Network [OSTI]

    Tobias Zingg

    2011-07-15T23:59:59.000Z

    Black holes with asymptotic anisotropic scaling are conjectured to be gravity duals of condensed matter system close to quantum critical points with non-trivial dynamical exponent z at finite temperature. A holographic renormalization procedure is presented that allows thermodynamic potentials to be defined for objects with both electric and magnetic charge in such a way that standard thermodynamic relations hold. Black holes in asymptotic Lifshitz spacetimes can exhibit paramagnetic behavior at low temperature limit for certain values of the critical exponent z, whereas the behavior of AdS black holes is always diamagnetic.

  15. Some remarks on black hole thermodynamics

    E-Print Network [OSTI]

    R. Y. Chiao

    2011-02-04T23:59:59.000Z

    Two thermodynamic "paradoxes" of black hole physics are re-examined. The first is that there is a thermal instability involving two coupled blackbody cavities containing two black holes, and second is that a classical black hole can swallow up entropy in the form of ambient blackbody photons without increasing its mass. The resolution of the second paradox by Bekenstein and by Hawking is re-visited. The link between Hawking radiation and Wigner's superluminal tunneling time is discussed using two equivalent Feynman diagrams, and Feynman's re-interpretation principle.

  16. Spectroscopy and Thermodynamics of MSW Black Hole

    E-Print Network [OSTI]

    Sebastian, Saneesh

    2013-01-01T23:59:59.000Z

    We study the thermodynamics and spectroscopy of a 2+1 dimensional black hole pro- posed by Mandal et. al1 . We put the background space time in Kruskal like co-ordinate and find period with respect to Euclidean time. Different thermodynamic quantities like entropy, specific heat, temperature etc are obtained. The adiabatic invariant for the black hole is found out and quantized using Bohr-Sommerfeld quantization rule. The study shows that the area spectrum of MSW black hole is equally spaced and the value of spacing is found to be h bar

  17. Spectroscopy and Thermodynamics of MSW Black Hole

    E-Print Network [OSTI]

    Saneesh Sebastian; V. C. Kuriakose

    2013-09-02T23:59:59.000Z

    We study the thermodynamics and spectroscopy of a 2+1 dimensional black hole pro- posed by Mandal et. al1 . We put the background space time in Kruskal like co-ordinate and find period with respect to Euclidean time. Different thermodynamic quantities like entropy, specific heat, temperature etc are obtained. The adiabatic invariant for the black hole is found out and quantized using Bohr-Sommerfeld quantization rule. The study shows that the area spectrum of MSW black hole is equally spaced and the value of spacing is found to be h bar

  18. Tunable optical properties of multilayers black phosphorus

    E-Print Network [OSTI]

    Low, Tony; Carvalho, A; Jiang, Yongjin; Wang, Han; Xia, Fengnian; Neto, A H Castro

    2014-01-01T23:59:59.000Z

    We calculated the optical conductivity tensor of multilayers black phosphorus using the Kubo formula within an effective low-energy Hamiltonian. The optical absorption spectra of multilayers black phosphorus are shown to vary sensitively with thickness, doping, and light polarization. In conjunction with experimental spectra obtained from infrared absorption spectroscopy, we discuss the role of interband coupling and disorder on the observed anisotropic absorption spectra. Multilayers black phosphorus might offer attractive alternatives to narrow gap compound semiconductors for optoelectronics across mid- to near-infrared frequencies.

  19. CHARYBDIS: A Black hole event generator.

    E-Print Network [OSTI]

    Harris, Chris M; Richardson, P; Webber, Bryan R

    model of black hole production and decay which can be interfaced to existing Monte Carlo programs using the Les Houches accord [4]. The major new theoretical input to the generator is the inclusion of the recently calculated grey-body factors for black... ? TH geometric arguments show that ?l,m? ? (?rh)2 in any number of dimensions, which means that at high energies the shape of the spectrum is like that of a black body. However the low energy behaviour of the grey-body factors is spin-dependent and also...

  20. Black hole hair in higher dimensions

    E-Print Network [OSTI]

    Chao Cao; Yi-Xin Chen; Jian-Long Li

    2008-04-02T23:59:59.000Z

    We study the property of matter in equilibrium with a static, spherically symmetric black hole in D-dimensional spacetime. It requires this kind of matter has an equation of state (\\omega\\equiv p_r/\\rho=-1/(1+2kn), k,n\\in \\mathbb{N}), which seems to be independent of D. However, when we associate this with specific models, some interesting limits on space could be found: (i)(D=2+2kn) while the black hole is surrounded by cosmic strings; (ii)the black hole can be surrounded by linear dilaton field only in 4-dimensional spacetime. In both cases, D=4 is special.

  1. Morphology of PolyethyleneCarbon Black Composites G. BEAUCAGE,1

    E-Print Network [OSTI]

    Beaucage, Gregory

    Morphology of Polyethylene­Carbon Black Composites G. BEAUCAGE,1 S. RANE,1 D. W. SCHAEFER,1 G. LONG-ray scattering (SAXS) study of a conductive grade of carbon black and carbon black­polymer composites(methyl methacrylate); carbon black; filler; composite; conductivity; percolation INTRODUCTION The morphology

  2. Phase transitions and Geometrothermodynamics of Regular black holes

    E-Print Network [OSTI]

    R. Tharanath; Jishnu Suresh; V. C. Kuriakose

    2014-06-16T23:59:59.000Z

    In this paper we study the thermodynamics and state space geometry of regular black hole solutions such as Bardeen black hole, Ay\\'{o}n-Beato and Garc\\'{i}a black hole, Hayward black hole and Berej-Matyjasek-Trynieki-Wornowicz black hole. We find that all these black holes show second order thermodynamic phase transitions(SOTPT) by observing discontinuities in heat capacity-entropy graphs as well as the cusp type double point in free energy-temperature graph. Using the formulation of geometrothermodynamics we again find the singularities in the heat capacity of the black holes by calculating the curvature scalar of the Legendre invariant metric.

  3. Reclaiming Blackness: (Counter) Narratives of Racial Kinship in Black Gay Mens Sexual Stories

    E-Print Network [OSTI]

    Chambers, Christopher Scott

    2012-07-16T23:59:59.000Z

    and Prevention CME Christian Methodist Episcopal church DL Down Low GLBT Gay, Lesbian, Bisexual and Transgendered HIV Human Immunodeficiency Virus MCC Metropolitan Community Church MSM Men Who Have Sex with Men NCBLG National Coalition of Black Lesbians... and Gays SBM Super Black Man SGL Same Gender Loving STDs Sexually Transmitted Diseases The Forum National Black Gay and Lesbian Leadership Forum TVC Traditional Values Coalition x TABLE OF CONTENTS Page ABSTRACT...

  4. Thermodynamics of Schwarzschild-de Sitter black hole: thermal stability of Nariai black hole

    E-Print Network [OSTI]

    Yun Soo Myung

    2008-03-28T23:59:59.000Z

    We study thermodynamics of the Schwarzschild-de Sitter black hole in five dimensions by introducing two temperatures based on the standard and Bousso-Hawking normalizations. We use the first-law of thermodynamics to derive thermodynamic quantities. The two temperatures indicate that the Nariai black hole is thermodynamically unstable. However, it seems that black hole thermodynamics favors the standard normalization, and does not favor the Bousso-Hawking normalization.

  5. Thermodynamics and evaporation of the noncommutative black hole

    E-Print Network [OSTI]

    Yun Soo Myung; Yong-Wan Kim; Young-Jai Park

    2007-01-21T23:59:59.000Z

    We investigate the thermodynamics of the noncommutative black hole whose static picture is similar to that of the nonsingular black hole known as the de Sitter-Schwarzschild black hole. It turns out that the final remnant of extremal black hole is a thermodynamically stable object. We describe the evaporation process of this black hole by using the noncommutativity-corrected Vaidya metric. It is found that there exists a close relationship between thermodynamic approach and evaporation process.

  6. Black hole evolution: I. Supernova-regulated black hole growth

    E-Print Network [OSTI]

    Dubois, Yohan; Silk, Joseph; Devriendt, Julien; Slyz, Adrianne; Teyssier, Romain

    2015-01-01T23:59:59.000Z

    The growth of a supermassive black hole (BH) is determined by how much gas the host galaxy is able to feed it, which in turn is controlled by the cosmic environment, through galaxy mergers and accretion of cosmic flows that time how galaxies obtain their gas, but also by internal processes in the galaxy, such as star formation and feedback from stars and the BH itself. In this paper, we study the growth of a 10^12 Msun halo at z=2, which is the progenitor of an archetypical group of galaxies at z=0, and of its central BH by means of a high-resolution zoomed cosmological simulation, the Seth simulation. We study the evolution of the BH driven by the accretion of cold gas in the galaxy, and explore the efficiency of the feedback from supernovae (SNe). For a relatively inefficient energy input from SNe, the BH grows at the Eddington rate from early times, and reaches self-regulation once it is massive enough. We find that at early cosmic times z>3.5, efficient feedback from SNe forbids the formation of a settled...

  7. Ethnic identification among blacks and whites

    E-Print Network [OSTI]

    Glass, Teresa Gail

    1996-01-01T23:59:59.000Z

    Two central questions drive this research: (1) Are there trends in ethnic identification among blacks and whites; and (2) Are there meaningful differences between groups that identify differently? I use descriptive and regression analysis...

  8. Energy of 4-Dimensional Black Hole, etc

    E-Print Network [OSTI]

    Dmitriy Palatnik

    2011-07-18T23:59:59.000Z

    In this letter I suggest possible redefinition of mass density, not depending on speed of the mass element, which leads to a more simple stress-energy for an object. I calculate energy of black hole.

  9. Topological Black Holes -- Outside Looking In

    E-Print Network [OSTI]

    R. B. Mann

    1997-09-15T23:59:59.000Z

    I describe the general mathematical construction and physical picture of topological black holes, which are black holes whose event horizons are surfaces of non-trivial topology. The construction is carried out in an arbitrary number of dimensions, and includes all known special cases which have appeared before in the literature. I describe the basic features of massive charged topological black holes in $(3+1)$ dimensions, from both an exterior and interior point of view. To investigate their interiors, it is necessary to understand the radiative falloff behaviour of a given massless field at late times in the background of a topological black hole. I describe the results of a numerical investigation of such behaviour for a conformally coupled scalar field. Significant differences emerge between spherical and higher genus topologies.

  10. Horizon Operator Approach to Black Hole Quantization

    E-Print Network [OSTI]

    G. 't Hooft

    1994-02-21T23:59:59.000Z

    The $S$-matrix Ansatz for the construction of a quantum theory of black holes is further exploited. We first note that treating the metric tensor $g_{\\m\

  11. Towards Black Hole Entropy in Shape Dynamics

    E-Print Network [OSTI]

    Gabriel Herczeg; Vasudev Shyam

    2014-10-21T23:59:59.000Z

    Shape dynamics is classical theory of gravity which agrees with general relativity in many important cases, but possesses different gauge symmetries and constraints. Rather than spacetime diffeomorphism invariance, shape dynamics takes spatial diffeomorphism invariance and spatial Weyl invariance as the fundamental gauge symmetries associated with the gravitational field. Since the area of the event horizon of a black hole transforms under a generic spatial Weyl transformation, there has been some doubt that one can speak sensibly about the thermodynamics of black holes in shape dynamics. The purpose of this paper is to show that by treating the event horizon of a black hole as an interior boundary, one can recover familiar notions of black hole thermodynamics in shape dynamics and define a gauge invariant entropy that agrees with general relativity.

  12. BLACK ENGLISH AND THE AMERICAN VALUE SYSTEM

    E-Print Network [OSTI]

    Drake, Glendon F.

    1973-10-01T23:59:59.000Z

    The strategy of enlightened bi-dialectalism used by the schools in the United States to deal with the problem of Black English is a significant attempt at social engineering. This attempt is motivated by basic linguistic ...

  13. The structure of the carbon black flame

    E-Print Network [OSTI]

    Anderson, W. Kermi

    1945-01-01T23:59:59.000Z

    THE STRUCTURE OF THE CARBON BLACK FLAME A Dissertation By W1 111 ami Kermit Anderson THEHSR UCOF Approval as to style and content recommended Head of tiie Department of Chemistry A Dissertation Submitted to the Faculty of the Agricultural... and Mechanical College of. Texas in Parti ail Fulfilment of the Requirements for the Degree of Doctor of Philosophy THE STRUCTURE OF THE CARBON BLACK FLAME Major Subject: Chemistry AB William Hermit Anderson:\\ t * August 1945 THE STRUCTURE OF THE. CARBON...

  14. Notes on Black Hole Fluctuations and Backreaction

    E-Print Network [OSTI]

    B. L. Hu; Alpan Raval; Sukanya Sinha

    1999-01-05T23:59:59.000Z

    In these notes we prepare the ground for a systematic investigation into the issues of black hole fluctuations and backreaction by discussing the formulation of the problem, commenting on possible advantages and shortcomings of existing works, and introducing our own approach via a stochastic semiclassical theory of gravity based on the Einstein-Langevin equation and the fluctuation-dissipation relation for a self-consistent description of metric fluctuations and dissipative dynamics of the black hole with backreaction of its Hawking radiance.

  15. Electromagnetic Beams Overpass the Black Hole Horizon

    E-Print Network [OSTI]

    Alexander Burinskii

    2008-06-16T23:59:59.000Z

    We show that the electromagnetic excitations of the Kerr black hole have very strong back reaction on metric. In particular, the electromagnetic excitations aligned with the Kerr congruence form the light-like beams which overcome horizon, forming the holes in it, which allows matter to escape interior. So, there is no information lost inside the black hole. This effect is based exclusively on the analyticity of the algebraically special solutions.

  16. Tritium level along Romanian Black Sea Coast

    SciTech Connect (OSTI)

    Varlam, C.; Stefanescu, I.; Popescu, I.; Faurescu, I. [National Inst. for Cryogenic and Isotopic Technologies, PO Box 10, Rm. Valcea, 24050 (Romania)

    2008-07-15T23:59:59.000Z

    Establishing the tritium level along the Romanian Black Sea Coast, after 10 years of exploitation of the nuclear power plant from Cernavoda, is a first step in evaluating its impact on the Black Sea ecosystem. The monitoring program consists of tritium activity concentration measurement in sea water and precipitation from Black Sea Coast between April 2005 and April 2006. The sampling points were spread over the Danube-Black Sea Canal - before the locks Agigea and Navodari, and Black Sea along the coast to the Bulgarian border. The average tritium concentration in sea water collected from the sampling locations had the value of 11.1 {+-} 2.1 TU, close to tritium concentration in precipitation. Although an operating nuclear power plant exists in the monitored area, the values of tritium concentration in two locations are slightly higher than those recorded elsewhere. To conclude, it could be emphasized that until now, Cernavoda NPP did not had any influence on the tritium concentration of the Black Sea Shore. (authors)

  17. Black liquor gasifier/gas turbine cogeneration

    SciTech Connect (OSTI)

    Consonni, S. [Politecnico di Milano (Italy). Dept. di Energetica; Larson, E.D.; Keutz, T.G. [Princeton Univ., NJ (United States); Berglin, N. [Chalmers Univ. of Technology, Goteborg (Sweden). Dept. of Heat and Power Technology

    1998-07-01T23:59:59.000Z

    The kraft process dominates pulp and paper production worldwide. Black liquor, a mixture of lignin and inorganic chemicals, is generated in this process as fiber is extracted from wood. At most kraft mills today, black liquor is burned in Tomlinson boilers to produce steam for on-site heat and power and to recover the inorganic chemicals for reuse in the process. Globally, the black liquor generation rate is about 85,000 MW{sub fuel} (or 0.5 million tonnes of dry solids per day), with nearly 50% of this in North America. The majority of presently installed Tomlinson boilers will reach the end of their useful lives during the next 5 to 20 years. As a replacement for Tomlinson-based cogeneration, black liquor-gasifier/gas turbine cogeneration promises higher electrical efficiency, with prospective environmental, safety, and capital cost benefits for kraft mills. Several companies are pursuing commercialization of black liquor gasification for gas turbine applications. This paper presents results of detailed performance modeling of gasifier/gas turbine cogeneration systems using different black liquor gasifiers modeled on proposed commercial designs.

  18. Asymptotically Lifshitz brane-world black holes

    SciTech Connect (OSTI)

    Ranjbar, Arash, E-mail: a_ranjbar@sbu.ac.ir; Sepangi, Hamid Reza, E-mail: hr-sepangi@sbu.ac.ir; Shahidi, Shahab, E-mail: s_shahidi@sbu.ac.ir

    2012-12-15T23:59:59.000Z

    We study the gravity dual of a Lifshitz field theory in the context of a RSII brane-world scenario, taking into account the effects of the extra dimension through the contribution of the electric part of the Weyl tensor. We study the thermodynamical behavior of such asymptotically Lifshitz black holes. It is shown that the entropy imposes the critical exponent z to be bounded from above. This maximum value of z corresponds to a positive infinite entropy as long as the temperature is kept positive. The stability and phase transition for different spatial topologies are also discussed. - Highlights: Black-Right-Pointing-Pointer Studying the gravity dual of a Lifshitz field theory in the context of brane-world scenario. Black-Right-Pointing-Pointer Studying the thermodynamical behavior of asymptotically Lifshitz black holes. Black-Right-Pointing-Pointer Showing that the entropy imposes the critical exponent z to be bounded from above. Black-Right-Pointing-Pointer Discussing the phase transition for different spatial topologies.

  19. Black Carbons Properties and Role in the Environment: A Comprehensive Review

    E-Print Network [OSTI]

    Shrestha, Gyami

    2010-01-01T23:59:59.000Z

    H. Can reducing black carbon emissions counteract globalinventory of black carbon emissions. Atmos. Environ. 1993,commonly studied form of carbon emissions. Black carbon (BC)

  20. Holographic superconductor in the exact hairy black hole

    E-Print Network [OSTI]

    Yun Soo Myung; Chanyong Park

    2011-09-13T23:59:59.000Z

    We study the charged black hole of hyperbolic horizon with scalar hair (charged Martinez-Troncoso-Zanelli: CMTZ black hole) as a model of analytic hairy black hole for holographic superconductor. For this purpose, we investigate the second order phase transition between CMTZ and hyperbolic Reissner-Nordstr\\"om-AdS (HRNAdS) black holes. However, this transition unlikely occur. As an analytic treatment for holographic superconductor, we develop superconductor in the bulk and superfluidity on the boundary using the CMTZ black hole below the critical temperature. The presence of charge destroys the condensates around the zero temperature, which is in accord with the thermodynamic analysis of the CMTZ black hole.

  1. Perturbative String Thermodynamics near Black Hole Horizons

    E-Print Network [OSTI]

    Thomas G. Mertens; Henri Verschelde; Valentin I. Zakharov

    2014-10-29T23:59:59.000Z

    We provide further computations and ideas to the problem of near-Hagedorn string thermodynamics near (uncharged) black hole horizons, building upon our earlier work JHEP 1403 (2014) 086. The relevance of long strings to one-loop black hole thermodynamics is emphasized. We then provide an argument in favor of the absence of $\\alpha'$-corrections for the (quadratic) heterotic thermal scalar action in Rindler space. We also compute the large $k$ limit of the cigar orbifold partition functions (for both bosonic and type II superstrings) which allows a better comparison between the flat cones and the cigar cones. A discussion is made on the general McClain-Roth-O'Brien-Tan theorem and on the fact that different torus embeddings lead to different aspects of string thermodynamics. The black hole/string correspondence principle for the 2d black hole is discussed in terms of the thermal scalar. Finally, we present an argument to deal with arbitrary higher genus partition functions, suggesting the breakdown of string perturbation theory (in $g_s$) to compute thermodynamical quantities in black hole spacetimes.

  2. The Environmental Impact of Supermassive Black Holes

    E-Print Network [OSTI]

    Abraham Loeb

    2004-08-10T23:59:59.000Z

    The supermassive black holes observed at the centers of almost all present-day galaxies, had a profound impact on their environment. I highlight the principle of self-regulation, by which supermassive black holes grow until they release sufficient energy to unbind the gas that feeds them from their host galaxy. This principle explains several observed facts, including the correlation between the mass of a central black hole and the depth of the gravitational potential well of its host galaxy, and the abundance and clustering properties of bright quasars in the redshift interval of z~2-6. At lower redshifts, quasars might have limited the maximum mass of galaxies through the suppression of cooling flows in X-ray clusters. The seeds of supermassive black holes were likely planted in dwarf galaxies at redshifts z>10, through the collapse of massive or supermassive stars. The minimum seed mass can be identified observationally through the detection of gravitational waves from black hole binaries by Advanced LIGO or LISA. Aside from shaping their host galaxies, quasar outflows filled the intergalactic medium with magnetic fields and heavy elements. Beyond the reach of these outflows, the brightest quasars at z>6 have ionized exceedingly large volumes of gas (tens of comoving Mpc) prior to global reionization, and must have suppressed the faint end of the galaxy luminosity function in these volumes before the same occurred through the rest of the universe.

  3. Investigating Dark Energy with Black Hole Binaries

    E-Print Network [OSTI]

    Laura Mersini-Houghton; Adam Kelleher

    2009-06-08T23:59:59.000Z

    The accelerated expansion of the universe is ascribed to the existence of dark energy. Black holes accretion of dark energy induces a mass change proportional to the energy density and pressure of the background dark energy fluid. The time scale during which the mass of black holes changes considerably is too long relative to the age of the universe, thus beyond detection possibilities. We propose to take advantage of the modified black hole masses for exploring the equation of state $w[z]$ of dark energy, by investigating the evolution of supermassive black hole binaries on a dark energy background. Deriving the signatures of dark energy accretion on the evolution of binaries, we find that dark energy imprints on the emitted gravitational radiation and on the changes in the orbital radius of the binary can be within detection limits for certain supermassive black hole binaries. In this talk I describe how binaries can provide a useful tool in obtaining complementary information on the nature of dark energy, based on the work done with A.Kelleher.

  4. Black Holes with Flavors of Quantum Hair?

    E-Print Network [OSTI]

    Gia Dvali

    2006-07-20T23:59:59.000Z

    We show that black holes can posses a long-range quantum hair of super-massive tensor fields, which can be detected by Aharonov-Bohm tabletop interference experiments, in which a quantum-hairy black hole, or a remnant particle, passes through the loop of a magnetic solenoid. The long distance effect does not decouple for an arbitrarily high mass of the hair-providing field. Because Kaluza-Klein and String theories contain infinite number of massive tensor fields, we study black holes with quantum Kaluza-Klein hair. We show that in five dimensions such a black hole can be interpreted as a string of `combed' generalized magnetic monopoles, with their fluxes confined along it. For the compactification on a translation-invariant circle, this substructure uncovers hidden flux conservation and quantization of the monopole charges, which constrain the quantum hair of the resulting four-dimensional black hole. For the spin-2 quantum hair this result is somewhat unexpected, since the constituent `magnetic' charges have no `electric' counterparts. Nevertheless, the information about their quantization is encoded in singularity.

  5. Neutrino Majorana Mass from Black Hole

    E-Print Network [OSTI]

    Yosuke Uehara

    2002-05-25T23:59:59.000Z

    We propose a new mechanism to generate the neutrino Majorana mass in TeV-scale gravity models. The black hole violates all non-gauged symmetries and can become the origin of lepton number violating processes. The fluctuation of higher-dimensional spacetime can result in the production of a black hole, which emits 2 neutrinos. If neutrinos are Majorana particles, this process is equivalent to the free propagation of a neutrino with the insertion of the black hole. From this fact, we derive the neutrino Majorana mass. The result is completely consistent with the recently observed evidence of neutrinoless double beta decay. And the obtained neutrino Majorana mass satisfies the constraint from the density of the neutrino dark matter, which affects the cosmic structure formation. Furthermore, we can explain the ultrahigh energy cosmic rays by the Z-burst scenario with it.

  6. Black Hole Chromosphere at the LHC

    E-Print Network [OSTI]

    Luis Anchordoqui; Haim Goldberg

    2003-02-26T23:59:59.000Z

    If the scale of quantum gravity is near a TeV, black holes will be copiously produced at the LHC. In this work we study the main properties of the light descendants of these black holes. We show that the emitted partons are closely spaced outside the horizon, and hence they do not fragment into hadrons in vacuum but more likely into a kind of quark-gluon plasma. Consequently, the thermal emission occurs far from the horizon, at a temperature characteristic of the QCD scale. We analyze the energy spectrum of the particles emerging from the "chromosphere", and find that the hard hadronic jets are almost entirely suppressed. They are replaced by an isotropic distribution of soft photons and hadrons, with hundreds of particles in the GeV range. This provides a new distinctive signature for black hole events at LHC.

  7. Black Hole Complementarity in Gravity's Rainbow

    E-Print Network [OSTI]

    Gim, Yongwan

    2015-01-01T23:59:59.000Z

    We calculate the required energy for duplication of information in the context of black hole complementarity in the rainbow Schwarzschild black hole. The resultant energy can be written as the well-defined limit given by the conventional result for the vanishing rainbow parameter which characterizes the deformation of the relativistic dispersion relation in the freely falling frame. It shows that the duplication of information in quantum mechanics could be not allowed below a certain critical value of the rainbow parameter; however, it could be possible above the critical value of the rainbow parameter, so that the consistent formulation in the rainbow Schwarzschild black hole requires additional constraints or any other resolutions for the latter case.

  8. Extremal limits and black hole entropy

    E-Print Network [OSTI]

    Sean M. Carroll; Matthew C. Johnson; Lisa Randall

    2009-01-08T23:59:59.000Z

    Taking the extremal limit of a non-extremal Reissner-Nordstr\\"om black hole (by externally varying the mass or charge), the region between the inner and outer event horizons experiences an interesting fate -- while this region is absent in the extremal case, it does not disappear in the extremal limit but rather approaches a patch of $AdS_2\\times S^2$. In other words, the approach to extremality is not continuous, as the non-extremal Reissner-Nordstr\\"om solution splits into two spacetimes at extremality: an extremal black hole and a disconnected $AdS$ space. We suggest that the unusual nature of this limit may help in understanding the entropy of extremal black holes.

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

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

    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...

  10. Improved recovery of tall oil from black liquors

    SciTech Connect (OSTI)

    Zucker, J.

    1980-12-09T23:59:59.000Z

    Applying a d.c. of less than 15 V to acidified black liquor separates a significant amount of tall oil remaining in the black liquor sludge. An apparatus with graphite electrodes for this process is described.

  11. Topological black holes in Horava-Lifshitz gravity

    SciTech Connect (OSTI)

    Cai Ronggen [Key Laboratory of Frontiers in Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, P.O. Box 2735, Beijing 100190 (China) and Kavli Institute for Theoretical Physics China (KITPC), Chinese Academy of Sciences, P.O. Box 2735, Beijing 100190 (China); Cao Liming [Asia Pacific Center for Theoretical Physics, Pohang, Gyeongbuk 790-784 (Korea, Republic of); Ohta, Nobuyoshi [Department of Physics, Kinki University, Higashi-Osaka, Osaka 577-8502 (Japan)

    2009-07-15T23:59:59.000Z

    We find topological (charged) black holes whose horizon has an arbitrary constant scalar curvature 2k in Horava-Lifshitz theory. Without loss of generality, one may take k=1, 0, and -1. The black hole solution is asymptotically anti-de Sitter with a nonstandard asymptotic behavior. Using the Hamiltonian approach, we define a finite mass associated with the solution. We discuss the thermodynamics of the topological black holes and find that the black hole entropy has a logarithmic term in addition to an area term. We find a duality in Hawking temperature between topological black holes in Horava-Lifshitz theory and Einstein's general relativity: the temperature behaviors of black holes with k=1, 0, and -1 in Horava-Lifshitz theory are, respectively, dual to those of topological black holes with k=-1, 0, and 1 in Einstein's general relativity. The topological black holes in Horava-Lifshitz theory are thermodynamically stable.

  12. Black Hills Energy (Gas)- Residential Energy Efficiency Rebate Programs

    Broader source: Energy.gov [DOE]

    Black Hills Energy offers its residential Iowa customers incentives to encourage energy efficiency in their homes. Black Hills Energy offers a free home energy evaluation to customers (both owners...

  13. The Development of the Emerald Programming Language Andrew P. Black

    E-Print Network [OSTI]

    Black, Andrew P.

    The Development of the Emerald Programming Language Andrew P. Black Portland State University black@cs.pdx.edu Norman C. Hutchinson University of British Columbia norm@cs.ubc.ca Eric Jul University of Copenhagen eric

  14. Dynamics of galaxy cores and supermassive black holes

    E-Print Network [OSTI]

    David Merritt

    2006-05-02T23:59:59.000Z

    Recent work on the dynamical evolution of galactic nuclei containing supermassive black holes is reviewed. Topics include galaxy structural properties; collisionless and collisional equilibria; loss-cone dynamics; and dynamics of binary and multiple supermassive black holes.

  15. CHARYBDIS: A Black Hole Event Generator

    E-Print Network [OSTI]

    C. M. Harris; P. Richardson; B. R. Webber

    2003-07-24T23:59:59.000Z

    CHARYBDIS is an event generator which simulates the production and decay of miniature black holes at hadronic colliders as might be possible in certain extra dimension models. It interfaces via the Les Houches accord to general purpose Monte Carlo programs like HERWIG and PYTHIA which then perform the parton evolution and hadronization. The event generator includes the extra-dimensional `grey-body' effects as well as the change in the temperature of the black hole as the decay progresses. Various options for modelling the Planck-scale terminal decay are provided.

  16. Might black holes reveal their inner secrets?

    E-Print Network [OSTI]

    Ted Jacobson; Thomas P. Sotiriou

    2010-06-09T23:59:59.000Z

    Black holes harbor a spacetime singularity of infinite curvature, where classical spacetime physics breaks down, and current theory cannot predict what will happen. However, the singularity is invisible from the outside because strong gravity traps all signals, even light, behind an event horizon. In this essay we discuss whether it might be possible to destroy the horizon, if a body is tossed into the black hole so as to make it spin faster and/or have more charge than a certain limit. It turns out that one could expose a "naked" singularity if effects of the body's own gravity can be neglected. We suspect however that such neglect is unjustified.

  17. BLACK HOLE ENTROPY IN HIGHER CURVATURE GRAVITY

    E-Print Network [OSTI]

    TED JACOBSON; GUNGWON KANG; ROBERT C. MYERS

    1995-02-27T23:59:59.000Z

    We discuss some recent results on black hole thermodynamics within the context of effective gravitational actions including higher-curvature interactions. Wald's derivation of the First Law demonstrates that black hole entropy can always be expressed as a local geometric density integrated over a space-like cross-section of the horizon. In certain cases, it can also be shown that these entropy expressions satisfy a Second Law. One such simple example is considered from the class of higher curvature theories where the Lagrangian consists of a polynomial in the Ricci scalar.

  18. How red is a quantum black hole?

    E-Print Network [OSTI]

    Viqar Husain; Oliver Winkler

    2005-05-30T23:59:59.000Z

    Radiating black holes pose a number of puzzles for semiclassical and quantum gravity. These include the transplanckian problem -- the nearly infinite energies of Hawking particles created near the horizon, and the final state of evaporation. A definitive resolution of these questions likely requires robust inputs from quantum gravity. We argue that one such input is a quantum bound on curvature. We show how this leads to an upper limit on the redshift of a Hawking emitted particle, to a maximum temperature for a black hole, and to the prediction of a Planck scale remnant.

  19. Black nickel selective absorber, optimization of parameters

    SciTech Connect (OSTI)

    Akinoglu, B.; Cercioglu, V.; Ecevit, A.

    1983-12-01T23:59:59.000Z

    Electroplated black nickel selective absorber is one of the most commercially used element of solar energy systems. Electrodeposition parameters such as time of deposition, pH, current density, electrolyte temperature should be optimized to produce the most efficient selective absorber. The topology of the substrate material is very effective on selectivity and it should also be optimized. In this study, by controlling the conditions of electrodeposition black nickel selective absorbers are produced and their reflectivities are measured. The effects of the electrodeposition parameters together with the topology of the substrate, on the selective properties are investigated.

  20. Tachyon Perturbation on Two Dimensional Black Hole

    E-Print Network [OSTI]

    Aniket Basu

    2014-07-03T23:59:59.000Z

    We study the black hole geometry in the presence of tachyonic perturbations, and solve for the form of allowed tachyonic hair in the presence of back reaction, and for the form of the metric under the assumption that only the metric is perturbed but not the dilaton. We evaluate the Kretschmann scalar and argue that the horizon becomes singular in the presence of tachyons, implying that the black hole has turned into a naked singularity. A form of the allowed tachyon potential emerges as a requirement of self-consistency of our solution.

  1. Chaotic Information Processing by Extremal Black Holes

    E-Print Network [OSTI]

    Axenides, Minos; Nicolis, Stam

    2015-01-01T23:59:59.000Z

    We review an explicit regularization of the AdS$_2$/CFT$_1$ correspondence, that preserves all isometries of bulk and boundary degrees of freedom. This scheme is useful to characterize the space of the unitary evolution operators that describe the dynamics of the microstates of extremal black holes in four spacetime dimensions. Using techniques from algebraic number theory to evaluate the transition amplitudes, we remark that the regularization scheme expresses the fast quantum computation capability of black holes as well as its chaotic nature.

  2. BlackGold Biofuels | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of InspectorConcentrating SolarElectricEnergyCTBarre BiomassTHIS PAGE ISJump to: navigation,BlackBlackGold

  3. Isotope Biogeochemistry of Diagenesis caused by a Black

    E-Print Network [OSTI]

    the coasts of Surinam and French Guyana #12;µ Black shales in Leg 207 sediments and pore water response depth

  4. Can the fluctuations of a black hole be treated thermodynamically?

    E-Print Network [OSTI]

    Kostyantyn Ropotenko

    2008-03-31T23:59:59.000Z

    Since the temperature of a typical Schwarzschild black hole is very low, some doubts are raised about whether the fluctuations of the black hole can be treated thermodynamically. It is shown that this is not the case: the thermodynamic fluctuations of a black hole are considerably larger than the corresponding quantum fluctuations. Moreover the ratio of the mean square thermodynamic fluctuation to the corresponding quantum fluctuation can be interpreted as a number of the effective constituents of a black hole.

  5. A Note on Black Hole Temperature and Entropy

    E-Print Network [OSTI]

    P. R. Silva

    2006-05-09T23:59:59.000Z

    We propose intuitive derivations of the Hawking temperature and the Bekenstein-Hawking entropy of a Schwarzschild black hole.

  6. Black holes in Born-Infeld extended new massive gravity

    SciTech Connect (OSTI)

    Ghodsi, Ahmad; Yekta, Davood Mahdavian [Department of Physics, Ferdowsi University of Mashhad, P.O. Box 1436, Mashhad (Iran, Islamic Republic of)

    2011-05-15T23:59:59.000Z

    In this paper we find different types of black holes for the Born-Infeld extended new massive gravity. Our solutions include (un)charged warped (anti-)de Sitter black holes for four and six derivative expanded action. We also look at the black holes in unexpanded Born-Infeld action. In each case we calculate the entropy, angular momentum and mass of the black holes. We also find the central charges for the conformal field theory duals.

  7. Particles and scalar waves in noncommutative charged black hole spacetime

    E-Print Network [OSTI]

    Bhar, Piyali; Biswas, Ritabrata; Mondal, U F

    2015-01-01T23:59:59.000Z

    In this paper we have discussed geodesics and the motion of test particle in the gravitational field of noncommutative charged black hole spacetime. The motion of massive and massless particle have been discussed seperately. A comparative study of noncommutative charged black hole and usual Reissner-Nordstrom black hole has been done. The study of effective potential has also been included. Finally, we have examined the scattering of scalar waves in noncommutative charged black hole spacetime.

  8. Entropy and Area of Black Holes in Loop Quantum Gravity

    E-Print Network [OSTI]

    I. B. Khriplovich

    2002-03-31T23:59:59.000Z

    Simple arguments related to the entropy of black holes strongly constrain the spectrum of the area operator for a Schwarzschild black hole in loop quantum gravity. In particular, this spectrum is fixed completely by the assumption that the black hole entropy is maximum. Within the approach discussed, one arrives in loop quantum gravity at a quantization rule with integer quantum numbers $n$ for the entropy and area of a black hole.

  9. Emission of scalar particles from cylindrical black holes

    E-Print Network [OSTI]

    H. Gohar; K. Saifullah

    2011-09-27T23:59:59.000Z

    We study quantum tunneling of scalar particles from black strings. For this purpose we apply WKB approximation and Hamilton-Jacobi method to solve the Klein-Gordon equation for outgoing trajectories. We find the tunneling probability of outgoing charged and uncharged scalars from the event horizon of black strings, and hence the Hawking temperature for these black configurations.

  10. Are black holes with hair a normal state of matter?

    SciTech Connect (OSTI)

    Nieuwenhuizen, Th. M. [Institute for Theoretical Physics, Science Park 904, P. O. Box 94485, 1090 GL Amsterdam (Netherlands)

    2011-03-28T23:59:59.000Z

    Recent observations put forward that quasars are black holes with a magnetic dipole moment and no event horizon. To model hairy black holes a quantum field for hydrogen is considered in curved space, coupled to the scalar curvature. An exact, regular solution for the interior metric occurs for supermassive black holes. The equation of state is p = -{rho}c{sup 2}/3.

  11. A Link Between Black Holes and the Golden Ratio

    E-Print Network [OSTI]

    J. A. Nieto

    2011-06-02T23:59:59.000Z

    We consider a variational formalism to describe black holes solution in higher dimensions. Our procedure clarifies the arbitrariness of the radius parameter and, in particular, the meaning of the event horizon of a black hole. Moreover, our formalism enables us to find a surprising link between black holes and the golden ratio.

  12. Location and Geology Fig 1. The Macasty black shale

    E-Print Network [OSTI]

    , Quebec, is organic-rich black shale and hosting oil and gas. It is equivalent to the Ithaca shaleLocation and Geology Fig 1. The Macasty black shale in the Anticosti Island in the Gulf of St. d13C for calcite disseminated in the black shale range from 2.6o to 2.8 / The values are lower

  13. 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.

  14. Black Holes and Sub-millimeter Dimensions

    E-Print Network [OSTI]

    Argyres, Philip C; March-Russell, John David; Argyres, Philip C.; Dimopoulos, Savas; March-Russell, John

    1998-01-01T23:59:59.000Z

    Recently, a new framework for solving the hierarchy problem was proposed which does not rely on low energy supersymmetry or technicolor. The fundamental Planck mass is at a TeV and the observed weakness of gravity at long distances is due the existence of new sub-millimeter spatial dimensions. In this letter, we study how the properties of black holes are altered in these theories. Small black holes---with Schwarzschild radii smaller than the size of the new spatial dimensions---are quite different. They are bigger, colder, and longer-lived than a usual $(3+1)$-dimensional black hole of the same mass. Furthermore, they primarily decay into harmless bulk graviton modes rather than standard-model degrees of freedom. We discuss the interplay of our scenario with the holographic principle. Our results also have implications for the bounds on the spectrum of primordial black holes (PBHs) derived from the photo-dissociation of primordial nucleosynthesis products, distortion of the diffuse gamma-ray spectrum, overcl...

  15. Black Holes in Einstein-Aether Theory

    E-Print Network [OSTI]

    Christopher Eling; Ted Jacobson

    2010-03-28T23:59:59.000Z

    We study black hole solutions in general relativity coupled to a unit timelike vector field dubbed the "aether". To be causally isolated a black hole interior must trap matter fields as well as all aether and metric modes. The theory possesses spin-0, spin-1, and spin-2 modes whose speeds depend on four coupling coefficients. We find that the full three-parameter family of local spherically symmetric static solutions is always regular at a metric horizon, but only a two-parameter subset is regular at a spin-0 horizon. Asymptotic flatness imposes another condition, leaving a one-parameter family of regular black holes. These solutions are compared to the Schwarzschild solution using numerical integration for a special class of coupling coefficients. They are very close to Schwarzschild outside the horizon for a wide range of couplings, and have a spacelike singularity inside, but differ inside quantitatively. Some quantities constructed from the metric and aether oscillate in the interior as the singularity is approached. The aether is at rest at spatial infinity and flows into the black hole, but differs significantly from the the 4-velocity of freely-falling geodesics.

  16. Geodesic study of a charged black hole

    E-Print Network [OSTI]

    Mehedi Kalam; Nur Farhad; Sk. Monowar Hossein

    2013-03-17T23:59:59.000Z

    The behavior of the timelike and null geodesics of charged E. Ay$\\acute{o}$n-Beato and A. Garcia (ABG) black hole are investigated. For circular and radial geodesics, we investigate all the possible motions by plotting the effective potentials for different parameters. In conclusion, we have shown that there is no phenomenon of \\textit{superradiance} in this case.

  17. Limits on New Physics from Black Holes

    E-Print Network [OSTI]

    Clifford Cheung; Stefan Leichenauer

    2014-08-02T23:59:59.000Z

    Black holes emit high energy particles which induce a finite density potential for any scalar field $\\phi$ coupling to the emitted quanta. Due to energetic considerations, $\\phi$ evolves locally to minimize the effective masses of the outgoing states. In theories where $\\phi$ resides at a metastable minimum, this effect can drive $\\phi$ over its potential barrier and classically catalyze the decay of the vacuum. Because this is not a tunneling process, the decay rate is not exponentially suppressed and a single black hole in our past light cone may be sufficient to activate the decay. Moreover, decaying black holes radiate at ever higher temperatures, so they eventually probe the full spectrum of particles coupling to $\\phi$. We present a detailed analysis of vacuum decay catalyzed by a single particle, as well as by a black hole. The former is possible provided large couplings or a weak potential barrier. In contrast, the latter occurs much more easily and places new stringent limits on theories with hierarchical spectra. Finally, we comment on how these constraints apply to the standard model and its extensions, e.g. metastable supersymmetry breaking.

  18. Pulsed combustion process for black liquor gasification

    SciTech Connect (OSTI)

    Durai-Swamy, K.; Mansour, M.N.; Warren, D.W.

    1991-02-01T23:59:59.000Z

    The objective of this project is to test an energy efficient, innovative black liquor recovery system on an industrial scale. In the MTCI recovery process, black liquor is sprayed directly onto a bed of sodium carbonate solids which is fluidized by steam. Direct contact of the black liquor with hot bed solids promotes high rates of heating and pyrolysis. Residual carbon, which forms as a deposit on the particle surface, is then gasified by reaction with steam. Heat is supplied from pulse combustor resonance tubes which are immersed within the fluid bed. A portion of the gasifier product gas is returned to the pulse combustors to provide the energy requirements of the reactor. Oxidized sulfur species are partially reduced by reaction with the gasifier products, principally carbon monoxide and hydrogen. The reduced sulfur decomposed to solid sodium carbonate and gaseous hydrogen sulfide (H{sub 2}S). Sodium values are recovered by discharging a dry sodium carbonate product from the gasifier. MTCI's indirectly heated gasification technology for black liquor recovery also relies on the scrubbing of H{sub 2}S for product gases to regenerate green liquor for reuse in the mill circuit. Due to concerns relative to the efficiency of sulfur recovery in the MTCI integrated process, an experimental investigation was undertaken to establish performance and design data for this portion of the system.

  19. Schwarzschild black hole in dark energy background

    E-Print Network [OSTI]

    Ngangbam Ishwarchandra; Ng. Ibohal; K. Yugindro Singh

    2014-09-27T23:59:59.000Z

    In this paper we present an exact solution of Einstein's field equations describing the Schwarzschild black hole in dark energy background. It is also regarded as an embedded solution that the Schwarzschild black hole is embedded into the dark energy space producing Schwarzschild-dark energy black hole. It is found that the space-time geometry of Schwarzschild-dark energy solution is non-vacuum Petrov type $D$ in the classification of space-times. We study the energy conditions (like weak, strong and dominant conditions) for the energy-momentum tensor of the Schwarzschild-dark energy solution. We also find that the energy-momentum tensor of the Schwarzschild-dark energy solution violates the strong energy condition due to the negative pressure leading to a repulsive gravitational force of the matter field in the space-time. It is shown that the time-like vector field for an observer in the Schwarzschild-dark energy space is expanding, accelerating, shearing and non-rotating. We investigate the surface gravity and the area of the horizons for the Schwarzschild-dark energy black hole.

  20. 4, 871891, 2007 Mobility of black

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    BGD 4, 871­891, 2007 Mobility of black carbon J. Leifeld et al. Title Page Abstract Introduction Discussion EGU Biogeosciences Discuss., 4, 871­891, 2007 www.biogeosciences-discuss.net/4/871/2007/ © Author ­ Published: 23 March 2007 Correspondence to: J. Leifeld (jens.leifeld@art.admin.ch) 871 #12;BGD 4, 871

  1. Supermassive Black Hole Binaries: The Search Continues

    E-Print Network [OSTI]

    Tamara Bogdanovic

    2014-06-19T23:59:59.000Z

    Gravitationally bound supermassive black hole binaries (SBHBs) are thought to be a natural product of galactic mergers and growth of the large scale structure in the universe. They however remain observationally elusive, thus raising a question about characteristic observational signatures associated with these systems. In this conference proceeding I discuss current theoretical understanding and latest advances and prospects in observational searches for SBHBs.

  2. Typechecking Polymorphism in Emerald Andrew P. Black

    E-Print Network [OSTI]

    Black, Andrew P.

    Typechecking Polymorphism in Emerald Andrew P. Black Digital Equipment Corporation Norman, distributed programming. c Digital Equipment Corporation and Norman Hutchinson 1991. All rights reserved by the National Science Foundation under Grant CCR-8701516. Norman Hutchinson was with the University of Arizona

  3. Six Sigma Black Belts Fight For Quality

    E-Print Network [OSTI]

    Vardeman, Stephen B.

    Six Sigma Black Belts Fight For Quality Ron Scott Ross Finnestad Rodney Kalsow IE 361 mini-paper 9/22/00 #12;Six Sigma is a breakthrough management strategy that is revolutionizing the world's top corporations. So what is Six Sigma? "It is a business process that allows companies to drastically improve

  4. Brief review on higher spin black holes

    E-Print Network [OSTI]

    Alfredo Perez; David Tempo; Ricardo Troncoso

    2014-05-12T23:59:59.000Z

    We review some relevant results in the context of higher spin black holes in three-dimensional spacetimes, focusing on their asymptotic behaviour and thermodynamic properties. For simplicity, we mainly discuss the case of gravity nonminimally coupled to spin-3 fields, being nonperturbatively described by a Chern-Simons theory of two independent sl(3,R) gauge fields. Since the analysis is particularly transparent in the Hamiltonian formalism, we provide a concise discussion of their basic aspects in this context; and as a warming up exercise, we briefly analyze the asymptotic behaviour of pure gravity, as well as the BTZ black hole and its thermodynamics, exclusively in terms of gauge fields. The discussion is then extended to the case of black holes endowed with higher spin fields, briefly signaling the agreements and discrepancies found through different approaches. We conclude explaining how the puzzles become resolved once the fall off of the fields is precisely specified and extended to include chemical potentials, in a way that it is compatible with the asymptotic symmetries. Hence, the global charges become completely identified in an unambiguous way, so that different sets of asymptotic conditions turn out to contain inequivalent classes of black hole solutions being characterized by a different set of global charges.

  5. Repackaging SRS Black Box TRU Waste

    SciTech Connect (OSTI)

    Swale, D. J.; Stone, K.A.; Milner, T. N.

    2006-01-09T23:59:59.000Z

    Historically, large items of TRU Waste, which were too large to be packaged in drums for disposal have been packaged in various sizes of custom made plywood boxes at the Savannah River Site (SRS), for many years. These boxes were subsequently packaged into large steel ''Black Boxes'' for storage at SRS, pending availability of Characterization and Certification capability, to facilitate disposal of larger items of TRU Waste. There are approximately 107 Black Boxes in inventory at SRS, each measuring some 18' x 12' x 7', and weighing up to 45,000 lbs. These Black Boxes have been stored since the early 1980s. The project to repackage this waste into Standard Large Boxes (SLBs), Standard Waste Boxes (SWB) and Ten Drum Overpacks (TDOP), for subsequent characterization and WIPP disposal, commenced in FY04. To date, 10 Black Boxes have been repackaged, resulting in 40 SLB-2's, and 37 B25 overpack boxes, these B25's will be overpacked in SLB-2's prior to shipping to WIPP. This paper will describe experience to date from this project.

  6. Ecology, Silviculture, and Management of Black Hills

    E-Print Network [OSTI]

    Fried, Jeremy S.

    . Battaglia United States Department of Agriculture Forest Service Rocky Mountain Research Station General Technical Report RMRS-GTR-97 September 2002 #12;Shepperd, Wayne D.; Battaglia, Michael A. 2002. Ecology in Arizona, and the Black Hills of South Dakota. Michael A. Battaglia is a research associate with METI

  7. Geodesics and Geodesic Deviation in static Charged Black Holes

    E-Print Network [OSTI]

    Ragab M. Gad

    2010-03-03T23:59:59.000Z

    The radial motion along null geodesics in static charged black hole space-times, in particular, the Reissner-Nordstr\\"om and stringy charged black holes are studied. We analyzed the properties of the effective potential. The circular photon orbits in these space-times are investigated. We found that the radius of circular photon orbits in both charged black holes are different and differ from that given in Schwarzschild space-time. We studied the physical effects of the gravitational field between two test particles in stringy charged black hole and compared the results with that given in Schwarzschild and Reissner-Nordstr\\"om black holes.

  8. Entropy spectra of single horizon black holes in two dimensions

    E-Print Network [OSTI]

    A. Lopez-Ortega

    2011-12-29T23:59:59.000Z

    The Hod conjecture proposes that the asymptotic quasinormal frequencies determine the entropy quantum of a black hole. Considering the Maggiore modification of this conjecture we calculate the entropy spectra of general, single horizon, asymptotically flat black holes in two-dimensional dilaton gravity. We also compute the entropy quanta of the two-dimensional Witten and AdS(2) black holes. Using the results for the entropy quanta of these two-dimensional black holes we discuss whether the produced values are generic. Finally we extend the results on the entropy spectra of other black holes.

  9. Quantum spectrum and statistic entropy of black hole

    E-Print Network [OSTI]

    Zhao Ren; Li Huaifan; Zhang Shengli

    2006-10-16T23:59:59.000Z

    Taking the horizon surface of the black hole as a compact membrane and solving the oscillation equation of this membrane by Klein-Gordon equation, we derive the frequencies of oscillation modes of the horizon surface, which are proportional to the radiation temperature of the black hole. However, the frequencies of oscillation modes are not equidistant. Using the distribution of obtained frequencies of oscillation mode we compute the statistic entropy of the black hole and obtain that the statistic entropy of the black hole is proportional to the area of the horizon. Therefore, it is proven that the quantum statistic entropy of the black hole is consistent with Bekenstein-Hawking entropy.

  10. Fate of black branes in Einstein-Gauss-Bonnet gravity

    SciTech Connect (OSTI)

    Suranyi, P.; Wijewardhana, L. C. R. [Department of Physics, University of Cincinnati, Cincinnati, Ohio, 45221-0011 (United States); Vaz, C. [Department of Physics, University of Cincinnati, Cincinnati, Ohio, 45221-0011 (United States); RWC, University of Cincinnati, Cincinnati, Ohio, 45221 (United States)

    2009-06-15T23:59:59.000Z

    Black branes are studied in Einstein-Gauss-Bonnet gravity. Evaporation drives black branes toward one of two singularities depending on the sign of {alpha}, the Gauss-Bonnet coupling. For positive {alpha} and sufficiently large ratio {radical}({alpha})/L, where L/2{pi} is the radius of compactification, black branes avoid the Gregory-Laflamme (GL) instability before reaching a critical state. No black branes with the radius of horizon smaller than the critical value can exist. Approaching the critical state branes have a nonzero Hawking temperature. For negative {alpha} all black branes encounter the GL instability. No black branes may exist outside of the interval of the critical values 0{<=}{beta}<3, where {beta}=1-8{alpha}/r{sub h}{sup 2} and r{sub h} is the radius of horizon of the black brane. The first order phase transition line of GL transitions ends in a second order phase transition point at {beta}=0.

  11. Acoustic clouds: standing sound waves around a black hole analogue

    E-Print Network [OSTI]

    Carolina L. Benone; Luis C. B. Crispino; Carlos Herdeiro; Eugen Radu

    2015-01-28T23:59:59.000Z

    Under certain conditions sound waves in fluids experience an acoustic horizon with analogue properties to those of a black hole event horizon. In particular, a draining bathtub-like model can give rise to a rotating acoustic horizon and hence a rotating black hole (acoustic) analogue. We show that sound waves, when enclosed in a cylindrical cavity, can form stationary waves around such rotating acoustic black holes. These acoustic perturbations display similar properties to the scalar clouds that have been studied around Kerr and Kerr-Newman black holes; thus they are dubbed acoustic clouds. We make the comparison between scalar clouds around Kerr black holes and acoustic clouds around the draining bathtub explicit by studying also the properties of scalar clouds around Kerr black holes enclosed in a cavity. Acoustic clouds suggest the possibility of testing, experimentally, the existence and properties of black hole clouds, using analog models.

  12. Acoustic clouds: standing sound waves around a black hole analogue

    E-Print Network [OSTI]

    Benone, Carolina L; Herdeiro, Carlos; Radu, Eugen

    2014-01-01T23:59:59.000Z

    Under certain conditions sound waves in fluids experience an acoustic horizon with analogue properties to those of a black hole event horizon. In particular, a draining bathtub-like model can give rise to a rotating acoustic horizon and hence a rotating black hole (acoustic) analogue. We show that sound waves, when enclosed in a cylindrical cavity, can form stationary waves around such rotating acoustic black holes. These acoustic perturbations display similar properties to the scalar clouds that have been studied around Kerr and Kerr-Newman black holes; thus they are dubbed acoustic clouds. We make the comparison between scalar clouds around Kerr black holes and acoustic clouds around the draining bathtub explicit by studying also the properties of scalar clouds around Kerr black holes enclosed in a cavity. Acoustic clouds suggest the possibility of testing, experimentally, the existence and properties of black hole clouds, using analog models.

  13. Geothermal: Sponsored by OSTI -- Recovery Act: Sub?Soil Gas and Fluid

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary)morphinan antagonist Journal Article: Crystal structureComposite--FORRemarks IGPPS DaysNEEDSInclusion

  14. Rholography, Black Holes and Scherk-Schwarz

    E-Print Network [OSTI]

    Nava Gaddam; Alessandra Gnecchi; Stefan Vandoren; Oscar Varela

    2014-12-23T23:59:59.000Z

    We present both the macroscopic and microscopic description of a class of near-extremal asymptotically flat black hole solutions in four (or five) dimensional gauged supergravity with R-symmetry gaugings obtained from Scherk-Schwarz reductions on a circle. The entropy of these black holes is counted holographically by the well known MSW (or D1/D5) system, with certain twisted boundary conditions labeled by a twist parameter \\rho. We find that the corresponding (0,4) (or (4,4)) superconformal algebras are exactly those studied by Schwimmer and Seiberg, using a twist on the outer automorphism group. The interplay between R-symmetries, \\rho-algebras and holography leads us to name our construction "Rholography".

  15. Black Hole Entropy and Induced Gravity

    E-Print Network [OSTI]

    Ted Jacobson

    1994-04-19T23:59:59.000Z

    In this short essay we review the arguments showing that black hole entropy is, at least in part, ``entanglement entropy", i.e., missing information contained in correlations between quantum field fluctuations inside and outside the event horizon. Although the entanglement entropy depends upon the matter field content of the theory, it turns out that so does the Bekenstein-Hawking entropy $A/4\\hbar G_{ren}$, in precisely the same way, because the effective gravitational constant $G_{ren}$ is renormalized by the very same quantum fluctuations. It appears most satisfactory if the entire gravitational action is ``induced", in the manner suggested by Sakharov, since then the black hole entropy is purebred entanglement entropy, rather than being hybrid with bare gravitational entropy (whatever that might be.)

  16. Geometric description of BTZ black holes thermodynamics

    E-Print Network [OSTI]

    Hernando Quevedo; Alberto Sanchez

    2008-11-15T23:59:59.000Z

    We study the properties of the space of thermodynamic equilibrium states of the Ba\\~nados-Teitelboim-Zanelli (BTZ) black hole in (2+1)-gravity. We use the formalism of geometrothermodynamics to introduce in the space of equilibrium states a $2-$dimensional thermodynamic metric whose curvature is non-vanishing, indicating the presence of thermodynamic interaction, and free of singularities, indicating the absence of phase transitions. Similar results are obtained for generalizations of the BTZ black hole which include a Chern-Simons term and a dilatonic field. Small logarithmic corrections of the entropy turn out to be represented by small corrections of the thermodynamic curvature, reinforcing the idea that thermodynamic curvature is a measure of thermodynamic interaction.

  17. Quantized black holes, their spectrum and radiation

    SciTech Connect (OSTI)

    Khriplovich, I. B. [Budker Institute of Nuclear Physics (Russian Federation)], E-mail: khriplovich@inp.nsk.su

    2008-04-15T23:59:59.000Z

    Under quite natural general assumptions, the following results are obtained. The maximum entropy of a quantized surface is demonstrated to be proportional to the surface area in the classical limit. The general structure of the horizon spectrum is found. In the special case of loop quantum gravity, the value of the Barbero-Immirzi parameter is found. The discrete spectrum of thermal radiation of a black hole fits the Wien profile. The natural widths of the lines are much smaller than the distances between them. The total intensity of the thermal radiation is estimated. If the density of quantized primordial black holes is close to the present upper limit on the dark-matter density in our Solar system, the sensitivity of modern detectors is close to that necessary for detecting this radiation.

  18. Economic aspects of black bases in Texas

    E-Print Network [OSTI]

    Schoen, Wayne Ayron

    1976-01-01T23:59:59.000Z

    the f easibility of using sand-asphalt stabilized base courses. Gregg reported that the sand-asphalt bases investigated in the field studies performed well under moving traffic. Moduli of resilient deformation of the bitumen-sand mixtures were... Ayron Schoen, B. S. , Texas ARK University Chairman of Advisory Committee: Dr. Jon A. Epps Although black base construction has gained increasing popularity in recent years, the rising costs of asphalt and asphalt materials have demanded that more...

  19. The high energy emission from black holes

    E-Print Network [OSTI]

    M. D. Caballero-Garcia; J. M. Miller; E. Kuulkers

    2007-11-06T23:59:59.000Z

    The origin of the high energy emission (X-rays and gamma-rays) from black holes is still a matter of debate. We present new evidence that hard X-ray emission in the low/hard state may not be dominated by thermal Comptonization. We present an alternative scenario for the origin of the high energy emission that is well suited to explain the high energy emission from GRO J1655-40.

  20. Refined Black Hole Ensembles and Topological Strings

    E-Print Network [OSTI]

    Mina Aganagic; Kevin Schaeffer

    2012-10-05T23:59:59.000Z

    We formulate a refined version of the Ooguri-Strominger-Vafa (OSV) conjecture. The OSV conjecture that Z_{BH} = |Z_{top}|^2 relates the BPS black hole partition function to the topological string partition function Z_{top}. In the refined conjecture, Z_{BH} is the partition function of BPS black holes counted with spin, or more precisely the protected spin character. Z_{top} becomes the partition function of the refined topological string, which is itself an index. Both the original and the refined conjecture are examples of large N duality in the 't Hooft sense. The refined conjecture applies to non-compact Calabi-Yau manifolds only, so the black holes are really BPS particles with large entropy, of order N^2. The refined OSV conjecture states that the refined BPS partition function has a large N dual which is captured by the refined topological string. We provide evidence that the conjecture holds by studying local Calabi-Yau threefolds consisting of line bundles over a genus g Riemann surface. We show that the refined topological string partition function on these geometries is computed by a two-dimensional TQFT. We also study the refined black hole partition function arising from N D4 branes on the Calabi-Yau, and argue that it reduces to a (q,t)-deformed version of two-dimensional SU(N) Yang-Mills. Finally, we show that in the large N limit this theory factorizes to the square of the refined topological string in accordance with the refined OSV conjecture.

  1. Density matrix of black hole radiation

    E-Print Network [OSTI]

    Lasma Alberte; Ram Brustein; Andrei Khmelnitsky; A. J. M. Medved

    2015-02-09T23:59:59.000Z

    Hawking's model of black hole evaporation is not unitary and leads to a mixed density matrix for the emitted radiation, while the Page model describes a unitary evaporation process in which the density matrix evolves from an almost thermal state to a pure state. We compare a recently proposed model of semiclassical black hole evaporation to the two established models. In particular, we study the density matrix of the outgoing radiation and determine how the magnitude of the off-diagonal corrections differs for the three frameworks. For Hawking's model, we find power-law corrections to the two-point functions that induce exponentially suppressed corrections to the off-diagonal elements of the full density matrix. This verifies that the Hawking result is correct to all orders in perturbation theory and also allows one to express the full density matrix in terms of the single-particle density matrix. We then consider the semiclassical theory for which the corrections, being non-perturbative from an effective field-theory perspective, are much less suppressed and grow monotonically in time. In this case, the R\\'enyi entropy for the outgoing radiation is shown to grow linearly at early times; but this growth slows down and the entropy eventually starts to decrease at the Page time. In addition to comparing models, we emphasize the distinction between the state of the radiation emitted from a black hole, which is highly quantum, and that of the radiation emitted from a typical classical black body at the same temperature.

  2. Entanglement from thermal black body radiation

    E-Print Network [OSTI]

    Daniel Braun

    2005-09-06T23:59:59.000Z

    Two non--interacting quantum systems which couple to a common environment with many degrees of freedom initially in thermal equilibrium can become entangled due to the indirect interaction mediated through this heat bath. I examine here the dynamics of reservoir induced entanglement for a heat bath consisting of a thermal electro--magnetic radiation field, such as black body radiation or the cosmic microwave background, and show how the effect can be understood as result of an effective induced interaction.

  3. Comparing quantum black holes and naked singularities

    E-Print Network [OSTI]

    T. P. Singh

    2000-12-21T23:59:59.000Z

    There are models of gravitational collapse in classical general relativity which admit the formation of naked singularities as well as black holes. These include fluid models as well as models with scalar fields as matter. Even if fluid models were to be regarded as unphysical in their matter content, the remaining class of models (based on scalar fields) generically admit the formation of visible regions of finite but arbitrarily high curvature. Hence it is of interest to ask, from the point of view of astrophysics, as to what a stellar collapse leading to a naked singularity (or to a visible region of very high curvature) will look like, to a far away observer. The emission of energy during such a process may be divided into three phases - (i) the classical phase, during which matter and gravity can both be treated according to the laws of classical physics, (ii) the semiclassical phase, when gravity is treated classically but matter behaves as a quantum field, and (iii) the quantum gravitational phase. In this review, we first give a summary of the status of naked singularities in classical relativity, and then report some recent results comparing the semiclassical phase of black holes with the semiclassical phase of spherical collapse leading to a naked singularity. In particular, we ask how the quantum particle creation during the collapse leading to a naked singularity compares with the Hawking radiation from a star collapsing to form a black hole. It turns out that there is a fundamental difference between the two cases. A spherical naked star emits only about one Planck energy during its semiclassical phase, and the further evolution can only be determined by the laws of quantum gravity. This contrasts with the semiclassical evaporation of a black hole.

  4. Electromagnetic wave scattering by Schwarzschild black holes

    E-Print Network [OSTI]

    Lus C. B. Crispino; Sam R. Dolan; Ednilton S. Oliveira

    2009-05-20T23:59:59.000Z

    We analyze the scattering of a planar monochromatic electromagnetic wave incident upon a Schwarzschild black hole. We obtain accurate numerical results from the partial wave method for the electromagnetic scattering cross section, and show that they are in excellent agreement with analytical approximations. The scattering of electromagnetic waves is compared with the scattering of scalar, spinor and gravitational waves. We present a unified picture of the scattering of all massless fields for the first time.

  5. Lowering kraft black liquor viscosity of ultrafiltration

    SciTech Connect (OSTI)

    Hill, M.K.; Violette, D.A.; Woerner, D.L.

    1988-10-01T23:59:59.000Z

    High viscosity is a major factor limiting the percentage total dissolved solids (%TDS) to which kraft black liquor (KBL), a spent pulping liquor, can be concentrated before it is burned to recover its fuel value and its inorganic chemicals. The effect on black liquor viscosity of removing high molecular weight lignin by ultrafiltration of 16% and 24% TDS liquors was studied. Viscosities of ultrafiltration permeates were reduced relative to feed black liquors. When a permeate was concentrated to higher %TDS levels, its viscosity decreased yet further relative to feed samples evaporated to similar solids levels. Retentate viscosity was very high relative to both feed and permeate. Ultrafiltration was carried out at 75/degrees/C using polysulfone membranes in a plate-and-frame or hollow fiber system. Flux rates varied greatly depending upon the specific liquor used. Flux was enhanced by increased temperature and increased linear velocity. The membrane molecular weight cutoff (MWCO) typically used was 50,000; increasing 100,000 or 200,000 did not enhance flux.

  6. In Situ Causticizing for Black Liquor Gasification

    SciTech Connect (OSTI)

    Scott Alan Sinquefield

    2005-10-01T23:59:59.000Z

    Black liquor gasification offers a number of attractive incentives to replace Tomlinson boilers but it also leads to an increase in the causticizing load. Reasons for this have been described in previous reports (FY04 ERC, et.al.). The chemistries have also been covered but will be reviewed here briefly. Experimental results of the causticizing reactions with black liquor are presented here. Results of the modeling work were presented in detail in the Phase 1 report. They are included in Table 2 for comparison but will not be discussed in detail. The causticizing agents were added to black liquor in the ratios shown in Table 1, mixed, and then spray-dried. The mixture ratios (doping levels) reflect amount calculated from the stoichiometry above to achieve specified conversions shown in the table. The solids were sieved to 63-90 microns for use in the entrained flow reactors. The firing conditions are shown in Table 2. Pictures and descriptions of the reactors can be found in the Phase 1 annual report. Following gasification, the solids (char) was collected and analyzed by coulometric titration (for carbonate and total carbon), and by inductively coupled plasma emission spectroscopy (ICP) for a wide array of metals.

  7. Quantization of rotating linear dilaton black holes

    E-Print Network [OSTI]

    I. Sakalli

    2014-06-19T23:59:59.000Z

    In this paper, we firstly prove that the adiabatic invariant quantity, which is commonly used in the literature for quantizing the rotating black holes (BHs) is fallacious. We then show how its corrected form should be. The main purpose of this paper is to study the quantization of 4-dimensional rotating linear dilaton black hole (RLDBH) spacetime describing with an action, which emerges in the Einstein-Maxwell-Dilaton-Axion (EMDA) theory. The RLDBH spacetime has a non-asymptotically flat (NAF) geometry. They reduces to the linear dilaton black hole (LDBH) metric when vanishing its rotation parameter $a$. While studying its scalar perturbations, it is shown that the Schr\\"odinger-like wave equation around the event horizon reduces to a confluent hypergeometric differential equation. Then the associated complex frequencies of the quasinormal modes (QNMs) are computed. By using those QNMs in the true definition of the rotational adiabatic invariant quantity, we obtain the quantum spectra of entropy/area for the RLDBH. It is found out that both spectra are discrete and equidistant. Besides, we reveal that the quantum spectra do not depend on $a$ in spite of the QNMs are modulated by it.

  8. Kerr black holes with scalar hair

    E-Print Network [OSTI]

    Herdeiro, Carlos A R

    2014-01-01T23:59:59.000Z

    We present a family of solutions of Einstein's gravity minimally coupled to a complex, massive scalar field, describing asymptotically flat, spinning black holes with scalar hair and a regular horizon. These hairy black holes (HBHs) are supported by rotation and have no static limit. Besides mass M and angular momentum J, they carry a conserved, continuous Noether charge Q measuring the scalar hair. HBHs branch off from the Kerr metric at the threshold of the superradiant instability and reduce to spinning boson stars in the limit of vanishing horizon area. They overlap with Kerr black holes for a set of (M,J) values. A single Killing vector field preserves the solutions, tangent to the null geodesic generators of the event horizon. HBHs can exhibit sharp physical differences when compared to the Kerr solution, such as J/M^2>1, quadrupole moment larger than J^2/M and larger orbital angular velocity at the innermost stable circular orbit. Families of HBHs connected to the Kerr geometry should exist in scalar (...

  9. Black hole fireworks: quantum-gravity effects outside the horizon spark black to white hole tunneling

    E-Print Network [OSTI]

    Hal M. Haggard; Carlo Rovelli

    2014-07-06T23:59:59.000Z

    We show that there is a classical metric satisfying the Einstein equations outside a finite spacetime region where matter collapses into a black hole and then emerges from a white hole. We compute this metric explicitly. We show how quantum theory determines the (long) time for the process to happen. A black hole can thus quantum-tunnel into a white hole. For this to happen, quantum gravity should affect the metric also in a small region outside the horizon: we show that contrary to what is commonly assumed, this is not forbidden by causality or by the semiclassical approximation, because quantum effects can pile up over a long time. This scenario alters radically the discussion on the black hole information puzzle.

  10. Black Carbon Emissions by Rocket Engines Types of rocket engines Emissions

    E-Print Network [OSTI]

    Toohey, Darin W.

    Black Carbon Emissions by Rocket Engines Types of rocket engines Emissions Liquid Hydrogen. Note: Black carbon does not deplete ozone. What happens is the black carbon emissions from the rocket. Other black carbon emissions: The number one contributor to black carbon is burning biomass. Also

  11. Black holes in extra dimensions can decay on the bulk

    E-Print Network [OSTI]

    A. K. Chaudhuri

    2003-01-08T23:59:59.000Z

    In the extra dimensional theories, with TeV scale Plank constant, black holes may be produced in the Large Hadron Collider experiments. We have argued that in the d-dimensional black hole, the intrinsically 4-dimensional brane fields do not see the same geometry at the horizon, as in a 4-dimensional space-time. Kaluza-Klein modes invades the brane and surroundings and the brane fields can be considered as a thermal system at the temperature of the black hole. From energy and entropy consideration, we show that whether or not a six-dimensional black hole will decay by emitting Kaluza-Klein modes or the standard model particles, will depend on the length scale of the extra dimensions as well as on the mass of the black hole. For higher dimensional black holes, Kaluza-Klein modes will dominate the decay.

  12. A toroidal black hole for the AGN phenomenon

    E-Print Network [OSTI]

    Fulvio Pompilio; S. M. Harun-or-Rashid; Matts Roos

    2000-08-30T23:59:59.000Z

    A new approach to the study of the AGN phenomenon is proposed, in which the nucleus activity is related to the metric of the inner massive black hole. The possibility of a Toroidal Black Hole (TBH), in contrast to the usual Spherical Black Hole (SBH), is discussed as a powerful tool in understanding AGN related phenomena, such as the energetics, the production of jets and the acceleration of particles, the shape of the magnetic field and the lifetime of nucleus activity.

  13. KKW Analysis for the Dyadosphere of a Charged Black Hole

    E-Print Network [OSTI]

    I. Radinschi

    2005-11-28T23:59:59.000Z

    The Keski-Vakkuri, Kraus and Wilczek (KKW) analysis is used to compute the temperature and entropy in the dyadosphere of a charged black hole solution. For our purpose we choose the dyadosphere region of the Reissner-Nordstrom black hole solution. Our results show that the expressions of the temperature and entropy in the dyadosphere of this charged black hole are not the Hawking temperature and the Bekenstein-Hawking entropy, respectively.

  14. Hawking radiation of Dirac particles from black strings

    SciTech Connect (OSTI)

    Ahmed, Jamil; Saifullah, K., E-mail: jamil_051@yahoo.com, E-mail: saifullah@qau.edu.pk [Department of Mathematics, Quaid-i-Azam University, Islamabad (Pakistan)

    2011-08-01T23:59:59.000Z

    Hawking radiation has been studied as a phenomenon of quantum tunneling in different black holes. In this paper we extend this semi-classical approach to cylindrically symmetric black holes. Using the Hamilton-Jacobi method and WKB approximation we calculate the tunneling probabilities of incoming and outgoing Dirac particles from the event horizon and find the Hawking temperature of these black holes. We obtain results both for uncharged as well as charged particles.

  15. Brownian Motion of Black Holes in Dense Nuclei

    E-Print Network [OSTI]

    David Merritt; Peter Berczik; Frederik Laun

    2006-10-18T23:59:59.000Z

    We evaluate the Brownian motion of a massive particle ("black hole") at the center of a galaxy using N-body simulations. Our galaxy models have power-law central density cusps like those observed at the centers of elliptical galaxies. The simulations show that the black hole achieves a steady-state kinetic energy that is substantially different than would be predicted based on the properties of the galaxy model in the absence of the black hole. The reason appears to be that the black hole responds to stars whose velocities have themselves been raised by the presence of the black hole. Over a wide range of density slopes and black hole masses, the black hole's mean kinetic energy is equal to what would be predicted under the assumption that it is in energy equipartition with stars lying within a distance ~r_h/2 from it, where r_h is the black hole's influence radius. The dependence of the Brownian velocity on black hole mass is approximately ~ 1/M^{1/(3-gamma)} with gamma the power-law index of the stellar density profile, rho~1/r^gamma. This is less steep than the 1/M dependence predicted in a model where the effect of the black hole on the stellar velocities is ignored. The influence of a stellar mass spectrum on the black hole's Brownian motion is also evaluated and found to be consistent with predictions from Chandrasekhar's theory. We use these results to derive a probability function for the mass of the Milky Way black hole based on a measurement of its proper motion velocity. Interesting constraints on M will require a velocity resolution exceeding 0.5 km/s.

  16. Classical and Quantum Properties of Liouville Black Holes

    E-Print Network [OSTI]

    R. B. Mann

    1994-04-25T23:59:59.000Z

    Black hole spacetimes can arise when a Liouville field is coupled to two- dimensional gravity. Exact solutions are obtained both classically and when quantum corrections due to back reaction effects are included. The black hole temperature depends upon the mass and the thermodynamic limit breaks down before evaporation of the black hole is complete, indicating that higher-loop effects must be included for a full description of the process.

  17. A Quantum Material Model of Static Schwarzschild Black Holes

    E-Print Network [OSTI]

    S. -T. Sung

    1997-03-16T23:59:59.000Z

    A quantum-mechanical prescription of static Einstein field equation is proposed in order to construct the matter-metric eigen-states in the interior of a static Schwarzschild black hole where the signature of space-time is chosen as (--++). The spectrum of the quantum states is identified to be the integral multiples of the surface gravity. A statistical explanation of black hole entropy is given and a quantisation rule for the masses of Schwarzschild black holes is proposed.

  18. Workplace Warriors: Identifying Team Practices of Appropriation in Software Ecosystems

    E-Print Network [OSTI]

    , but also how it is appropriated by the users (who are increasingly understood as prosumers instead of mere

  19. Sandia National Laboratories: Careers: Special Programs: Wounded Warrior

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary)morphinanInformation Desert Southwest RegionatSearch WelcomeScience SSRL ScienceCRF Linde,

  20. Ancient Warriors and the Origin of Chinese Purple

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAbout theOFFICEAmes Laboratory Site| DepartmentInformation Ancient

  1. Black Holes as Conformal Field Theories on Horizons

    E-Print Network [OSTI]

    Halyo, Edi

    2015-01-01T23:59:59.000Z

    We show that any nonextreme black hole can be described by a state with $L_0=E_R$ in a $D=2$ chiral conformal field theory with central charge $c=12E_R$ where $E_R$ is the dimensionless Rindler energy of the black hole. The theory lives in the very near horizon region, i.e. around the origin of Rindler space. Black hole hair is the momentum along the Euclidean dimensionless Rindler time direction. As evidence, we show that $D$--dimensional Schwarzschild black holes and $D=2$ dilatonic ones that are obtained from them by spherical reduction are described by the same conformal field theory states.

  2. Origin of palladium black by an infrared spectroscopic method

    SciTech Connect (OSTI)

    Vozdvizhenskii, V.F.; Levintova, T.D.; Sokol'skii, D.V.

    1987-03-01T23:59:59.000Z

    Metal blacks are used as catalysts in a number of organic synthesis processes. Using the method of matrix insulation of blacks obtained from organometallic compounds in the inert atmosphere the IR spectra have been recorded for carbon monoxide adsorbed on actual palladium blacks. The controllable mild conditions for reduction of the initial complex by hydrazine hydrate provide a means of separating the intermediate states of this process. By discontinuing at various stages the reduction of the organometallic complex being investigated the authors have obtained IR spectra of carbon monoxide characterizing the stages of forming the metallic palladium black.

  3. Improved methods for simulating nearly extremal binary black holes

    E-Print Network [OSTI]

    Mark A. Scheel; Matthew Giesler; Daniel A. Hemberger; Geoffrey Lovelace; Kevin Kuper; Michael Boyle; Bela Szilagyi; Lawrence E. Kidder

    2014-12-04T23:59:59.000Z

    Astrophysical black holes could be nearly extremal (that is, rotating nearly as fast as possible); therefore, nearly extremal black holes could be among the binaries that current and future gravitational-wave observatories will detect. Predicting the gravitational waves emitted by merging black holes requires numerical-relativity simulations, but these simulations are especially challenging when one or both holes have mass $m$ and spin $S$ exceeding the Bowen-York limit of $S/m^2=0.93$. We present improved methods that enable us to simulate merging, nearly extremal black holes more robustly and more efficiently. We use these methods to simulate an unequal-mass, precessing binary black hole coalescence, where the larger black hole has $S/m^2=0.99$. We also use these methods to simulate a non-precessing binary black hole coalescence, where both black holes have $S/m^2=0.994$, nearly reaching the Novikov-Thorne upper bound for holes spun up by thin accretion disks. We demonstrate numerical convergence and estimate the numerical errors of the waveforms; we compare numerical waveforms from our simulations with post-Newtonian and effective-one-body waveforms; we compare the evolution of the black-hole masses and spins with analytic predictions; and we explore the effect of increasing spin magnitude on the orbital dynamics (the so-called "orbital hangup" effect).

  4. U-012: BlackBerry Enterprise Server Collaboration Service Bug...

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

    Advisory ID: KB28524 SecurityTracker Alert ID: 1026179 CVE-2011-0290 IMPACT ASSESSMENT: Medium Discussion: A vulnerability exists in the BlackBerry Collaboration Service...

  5. Primordial black hole evolution in tensor-scalar cosmology

    E-Print Network [OSTI]

    Ted Jacobson

    1999-09-06T23:59:59.000Z

    A perturbative analysis shows that black holes do not remember the value of the scalar field $\\phi$ at the time they formed if $\\phi$ changes in tensor-scalar cosmology. Moreover, even when the black hole mass in the Einstein frame is approximately unaffected by the changing of $\\phi$, in the Jordan-Fierz frame the mass increases. This mass increase requires a reanalysis of the evaporation of primordial black holes in tensor-scalar cosmology. It also implies that there could have been a significant magnification of the (Jordan-Fierz frame) mass of primordial black holes.

  6. Argonne's African American Black Club awards scholarships to...

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

    students July 30, 2014 Tweet EmailPrint The African American Black Club (AABC) at Argonne has awarded four scholarships to promising local Illinois high school students to...

  7. National Conference of Black Mayors, Inc. | Department of Energy

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

    Black Mayors, Inc., members' capacity for energy and environmental planning through computer-based technology, Internet access, and a training workshop. National Conference of...

  8. Black Pine Engineering Wins Clean Energy Trust Clean Energy Challenge...

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

    the Energy Innovation Portal Last week the student team of Black Pine Engineering from Michigan State University took top honors at the Eastern Midwest regional competition of...

  9. Black Hills Energy (Electric)- Residential Energy Efficiency Program

    Broader source: Energy.gov [DOE]

    Black Hills Energy (BHE) offers rebates for residential Colorado customers who purchase energy efficient residential equipment. This program offers rebates for customers who purchase and install...

  10. Black Hills Energy (Gas)- Commercial Energy Efficiency Rebate Programs

    Broader source: Energy.gov [DOE]

    Black Hills Energy offers commercial and industrial customers incentives to encourage energy efficiency in eligible businesses. Prescriptive rebates are available for furnace and boiler...

  11. Black Hills Energy (Gas)- Commercial Energy Efficiency Program

    Broader source: Energy.gov [DOE]

    Black Hills Energy offers multiple programs for Colorado commercial and industrial customers to save natural gas in eligible facilities. The commercial prescriptive rebate program provides...

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

    Broader source: Energy.gov [DOE]

    Black Hills Energy offers multiple programs for its Colorado commercial and industrial customers to save electricity in their facilities. The commercial prescriptive rebate program provides...

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

    Broader source: Energy.gov [DOE]

    Black Hills Energy (BHE) offers a variety of rebates for residential Colorado customers who purchase and install energy efficient natural gas appliances, heating equipment and insulation materials....

  14. Small Hairy Black Holes in Global AdS Spacetime

    E-Print Network [OSTI]

    Pallab Basu; Jyotirmoy Bhattacharya; Sayantani Bhattacharyya; R. Loganayagam; Shiraz Minwalla; V. Umesh

    2010-05-16T23:59:59.000Z

    We study small charged black holes in global AdS spacetime in the presence of a charged massless minimally coupled scalar field. In a certain parameter range these black holes suffer from well known superradiant instabilities. We demonstrate that the end point of the resultant tachyon condensation process is a hairy black hole which we construct analytically in a perturbative expansion in the black hole radius. At leading order our solution is a small undeformed RNAdS black hole immersed into a charged scalar condensate that fills the AdS `box'. These hairy black hole solutions appear in a two parameter family labelled by their mass and charge. Their mass is bounded from below by a function of their charge; at the lower bound a hairy black hole reduces to a regular horizon free soliton which can also be thought of as a nonlinear Bose condensate. We compute the microcanonical phase diagram of our system at small mass, and demonstrate that it exhibits a second order `phase transition' between the RNAdS black hole and the hairy black hole phases.

  15. Absorption of scalars by extremal black holes in string theory

    E-Print Network [OSTI]

    Filipe Moura

    2014-06-13T23:59:59.000Z

    We show that the low frequency absorption cross section of minimally coupled massless scalar fields by extremal spherically symmetric black holes in d dimensions in the presence of string-theoretical alpha' corrections is equal to the horizon area. Classically one has the relation sigma=4GS between the absorption cross section and the black hole entropy. We discuss the validity of such relation in the presence of alpha' corrections for extremal black holes, both nonsupersymmetric and supersymmetric. The examples we consider seem to indicate that this relation is verified in the presence of alpha' corrections for supersymmetric black holes, but not for nonsupersymmetric ones.

  16. Extremal charged rotating dilaton black holes in odd dimensions

    SciTech Connect (OSTI)

    Allahverdizadeh, Masoud; Kunz, Jutta; Navarro-Lerida, Francisco [Institut fuer Physik, Universitaet Oldenburg, Postfach 2503 D-26111 Oldenburg (Germany); Departamento de Fisica Atomica, Molecular y Nuclear, Ciencias Fisicas Universidad Complutense de Madrid, E-28040 Madrid (Spain)

    2010-09-15T23:59:59.000Z

    Employing higher-order perturbation theory, we find a new class of charged rotating black hole solutions of Einstein-Maxwell-dilaton theory with general dilaton coupling constant. Starting from the Myers-Perry solutions, we use the electric charge as the perturbative parameter, and focus on extremal black holes with equal-magnitude angular momenta in odd dimensions. We perform the perturbations up to 4th order for black holes in 5 dimensions and up to 3rd order in higher odd dimensions. We calculate the physical properties of these black holes and study their dependence on the charge and the dilaton coupling constant.

  17. Extremal Charged Rotating Dilaton Black Holes in Odd Dimensions

    E-Print Network [OSTI]

    Masoud Allahverdizadeh; Jutta Kunz; Francisco Navarro-Lerida

    2010-07-24T23:59:59.000Z

    Employing higher order perturbation theory, we find a new class of charged rotating black hole solutions of Einstein-Maxwell-dilaton theory with general dilaton coupling constant. Starting from the Myers-Perry solutions, we use the electric charge as the perturbative parameter, and focus on extremal black holes with equal-magnitude angular momenta in odd dimensions. We perform the perturbations up to 4th order for black holes in 5 dimensions and up to 3rd order in higher odd dimensions. We calculate the physical properties of these black holes and study their dependence on the charge and the dilaton coupling constant.

  18. Homogeneous Einstein Metrics on SU(n) Manifolds, Hoop Conjecture for Black Rings, and Ergoregions in Magnetised Black Hole Spacetimes

    E-Print Network [OSTI]

    Mujtaba, Abid Hasan

    2013-01-09T23:59:59.000Z

    HOMOGENEOUS EINSTEIN METRICS ON SU(n) MANIFOLDS, HOOP CONJECTURE FOR BLACK RINGS, AND ERGOREGIONS IN MAGNETISED BLACK HOLE SPACETIMES A Dissertation by ABID HASAN MUJTABA Submitted to the O ce of Graduate Studies of Texas A&M University... Subject: Physics Copyright 2013 Abid Hasan Mujtaba ABSTRACT This Dissertation covers three aspects of General Relativity: inequivalent Einstein metrics on Lie Group Manifolds, proving the Hoop Conjecture for Black Rings, and investigating ergoregions...

  19. A southern black community comes of age: black San Antonio in the Great Depression, 1930-1941

    E-Print Network [OSTI]

    Jackson, Charles Christopher

    1989-01-01T23:59:59.000Z

    A&M University Press, 1984) compares the Depression This thesis follows the format of the Journal of 9 t ~Ht experiences of black, white, and Mexican American women of San Antonio. Judy Kaaz Doyle's "Maury Maverick and Racial Politics in San...A SOUTHERN BLACK COMMUNITY COMES OF AGE: BLACK SAN ANTONIO IN THE GREAT DEPRESSION, 1930-1941 A Thesis by CHARLES CHRISTOPHER JACKSON Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment...

  20. Extraneous Carbon Assessments in Radiocarbon Measurements of Black Carbon in Environmental Matrices

    E-Print Network [OSTI]

    Coppola, Alysha; Ziolkowski, L. A.; Druffel, E. R. M.

    2013-01-01T23:59:59.000Z

    rived (black/elemental) carbon in soils and sediments usingbon measurements of black carbon in aerosols and oceanMWI, Noack AG. 2000. Black carbon in soils and sediments:

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

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

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

  2. Entropy: From Black Holes to Ordinary Systems

    E-Print Network [OSTI]

    J. P. Badiali

    2005-05-11T23:59:59.000Z

    Several results of black holes thermodynamics can be considered as firmly founded and formulated in a very general manner. From this starting point we analyse in which way these results may give us the opportunity to gain a better understanding in the thermodynamics of ordinary systems for which a pre-relativistic description is sufficient. First, we investigated the possibility to introduce an alternative definition of the entropy basically related to a local definition of the order in a spacetime model rather than a counting of microstates. We show that such an alternative approach exists and leads to the traditional results provided an equilibrium condition is assumed. This condition introduces a relation between a time interval and the reverse of the temperature. We show that such a relation extensively used in the black hole theory, mainly as a mathematical trick, has a very general and physical meaning here; in particular its derivation is not related to the existence of a canonical density matrix. Our dynamical approach of thermodynamic equilibrium allows us to establish a relation between action and entropy and we show that an identical relation exists in the case of black holes. The derivation of such a relation seems impossible in the Gibbs ensemble approach of statistical thermodynamics. From these results we suggest that the definition of entropy in terms of order in spacetime should be more general that the Boltzmann one based on a counting of microstates. Finally we point out that these results are obtained by reversing the traditional route going from the Schr\\"{o}dinger equation to statistical thermodynamics.

  3. Formation of subhorizon black holes from preheating

    E-Print Network [OSTI]

    E. Torres-Lomas; Juan Carlos Hidalgo; Karim A. Malik; L. Arturo Urea-Lpez

    2014-04-29T23:59:59.000Z

    We study the production of primordial black holes (PBHs) during the preheating stage that follows a chaotic inflationary phase. The scalar fields present in the process are evolved numerically using a modified version of the HLATTICE code. From the output of the numerical simulation, we compute the probability distribution of curvature fluctuations, paying particular attention to sub-horizon scales. We find that in some specific models these modes grow to large amplitudes developing highly non-Gaussian probability distributions. We then calculate PBH abundances using the standard Press-Schechter criterion and find that overproduction of PBHs is likely in some regions of the chaotic preheating parameter space.

  4. A black potential for spin less particles

    E-Print Network [OSTI]

    Ananya Ghatak; Mohammad Hasan; Bhabani Prasad Mandal

    2014-12-02T23:59:59.000Z

    We consider the most general non-Hermitian Hulthen potential to study the scattering of spin-less relativistic particles. The conditions for CC, SS and CPA are obtained analytically for this potential. We show that almost total absorption occurs for entire range of incidence energy for certain parameter ranges of the potential and hence term this as `black potential'. Time reversed of the same potential shows perfect emission for the entire range of particle energy. We also present the classical analog of this potential in terms of waveguide cross section.

  5. Conformal Invariance of Black Hole Temperature

    E-Print Network [OSTI]

    Ted Jacobson; Gungwon Kang

    1993-07-06T23:59:59.000Z

    It is shown that the surface gravity and temperature of a stationary black hole are invariant under conformal transformations of the metric that are the identity at infinity. More precisely, we find a conformal invariant definition of the surface gravity of a conformal Killing horizon that agrees with the usual definition(s) for a true Killing horizon and is proportional to the temperature as defined by Hawking radiation. This result is reconciled with the intimate relation between the trace anomaly and the Hawking effect, despite the {\\it non}invariance of the trace anomaly under conformal transformations.

  6. Black Hole Thermodynamics and Lorentz Symmetry

    E-Print Network [OSTI]

    Ted Jacobson; Aron C. Wall

    2010-02-04T23:59:59.000Z

    Recent developments point to a breakdown in the generalized second law of thermodynamics for theories with Lorentz symmetry violation. It appears possible to construct a perpetual motion machine of the second kind in such theories, using a black hole to catalyze the conversion of heat to work. Here we describe and extend the arguments leading to that conclusion. We suggest the inference that local Lorentz symmetry may be an emergent property of the macroscopic world with origins in a microscopic second law of causal horizon thermodynamics.

  7. Geodesic Study of Regular Hayward Black Hole

    E-Print Network [OSTI]

    G. Abbas; U. Sabiullah

    2014-06-03T23:59:59.000Z

    This paper is devoted to study the geodesic structure of regular Hayward black hole. The timelike and null geodesic have been studied explicitly for radial and non-radial motion. For timelike and null geodesic in radial motion there exists analytical solution, while for non-radial motion the effective potential has been plotted, which investigates the position and turning points of the particle. It has been found that massive particle moving along timelike geodesics path are dragged towards the BH and continues move around BH in particular orbits.

  8. Fundamental studies of black liquor combustion

    SciTech Connect (OSTI)

    Clay, D.T.; Lien, S.J.; Grace, T.M.; Brown, C.A.; Empie, H.L.; Macek, A.; Amin, N.; Charangundla, S.R.

    1990-03-01T23:59:59.000Z

    The fundamentals of black liquor combustion are being studied in a project being carried out for the US Department of Energy by the Institute of Paper Science Technology (IPST, formerly the Institute of Paper Chemistry) and the National Institute of Science Technology (NIST, formerly the National Bureau of Standards). The project was divided into four phases. This report covers the completion of Phase 1 (in-flight processes), the results of all of the work on Phase 2 (char bed processes), Phase 3 (fume processes), and Phase 4 (furnace simulation). 41 refs., 62 figs., 30 tabs.

  9. Black River Electric Coop | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of Inspector GeneralDepartmentAUDIT REPORTOpenWendeGuo Feng Bio JumpVenturesCoral Capital JumpBlack River

  10. Black Diamond Power Co | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 NoPublic Utilities Address: 160Benin: Energy ResourcesJersey:form ViewBlack Diamond Power Co Jump to: navigation,

  11. Black Hills Corporation | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 NoPublic Utilities Address: 160Benin: Energy ResourcesJersey:form ViewBlack Diamond Power Co JumpHawk County,

  12. Black Hills Power Inc | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 NoPublic Utilities Address: 160Benin: Energy ResourcesJersey:form ViewBlack Diamond Power Co JumpHawk County,Power

  13. BlackHawk Fund | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 NoPublic Utilities Address: 160Benin: Energy ResourcesJersey:form ViewBlack Diamond Power CoWolf, Wisconsin:

  14. Black Mountain Insulation | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of InspectorConcentrating SolarElectricEnergyCTBarre BiomassTHIS PAGE ISJump to: navigation,Black Hills Name:

  15. Lumens Placard (Black) | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarly Career Scientists'Montana.ProgramJulietipDepartmentJuneWhenJulyBadgesSeptemberoflumens_placard-black.eps

  16. Thermodynamics of (2+1)-dimensional acoustic black hole based on the generalized uncertainty principle

    E-Print Network [OSTI]

    Wontae Kim; Edwin J. Son; Myungseok Yoon

    2008-01-09T23:59:59.000Z

    We study thermodynamic quantities of an acoustic black hole and its thermodynamic stability in a cavity based on the generalized uncertainty principle. It can be shown that there is a minimal black hole which can be a stable remnant after black hole evaporation. Moreover, the behavior of the free energy shows that the large black hole is stable too. Therefore, the acoustic black hole can decay into the remnant or the large black hole.

  17. Using the master's tools : representations of blackness and the strategies of stereotype

    E-Print Network [OSTI]

    Zygmonski, Aimee

    2010-01-01T23:59:59.000Z

    Watermelon, Black Woman with Drumstick, and other-worldlyBlack Woman with Drumstick, making obvious connotations toWith Watermelon? and With Drumstick? I would argue the

  18. E-Print Network 3.0 - ads schwarzschild black Sample Search Results

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

    spacetime. However, unlike shock matching outside a Black Hole... to infinity along a geodesic of the Schwarzschild metric outside the Black Hole. Thus the OS solution gives... ,...

  19. E-Print Network 3.0 - asian black latino Sample Search Results

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

    Ethnic Summary: IndianNative American Asian Black or African American HispanicLatino White Multi-Racial Unspecified... Native American Asian Black or African American Hispanic...

  20. Black Carbons Properties and Role in the Environment: A Comprehensive Review

    E-Print Network [OSTI]

    Shrestha, Gyami

    2010-01-01T23:59:59.000Z

    NOAA/ESRL. Mauna Loa Carbon Dioxide Annual Mean Data.H. Can reducing black carbon emissions counteract globalanalysis of black carbon in soils. Global Biogeochem. Cycle.

  1. Nonrotating black hole in a post-Newtonian tidal environment

    E-Print Network [OSTI]

    Stephanne Taylor; Eric Poisson

    2008-09-11T23:59:59.000Z

    We examine the motion and tidal dynamics of a nonrotating black hole placed within a post-Newtonian external spacetime. The tidal perturbation created by the external environment is treated as a small perturbation. At a large distance from the black hole, the gravitational field of the external distribution of matter is assumed to be sufficiently weak to be adequately described by the (first) post-Newtonian approximation to general relativity. There, the black hole is treated as a monopole contribution to the total gravitational field. There exists an overlap in the domains of validity of each description, and the black-hole and post-Newtonian metrics are matched in the overlap. The matching procedure produces the equations of motion for the black hole and the gravito-electric and gravito-magnetic tidal fields acting on the black hole. We first calculate the equations of motion and tidal fields by making no assumptions regarding the nature of the post-Newtonian environment; this could contain a continuous distribution of matter or any number of condensed bodies. We next specialize our discussion to a situation in which the black hole is a member of a post-Newtonian two-body system. As an application of our results, we examine the geometry of the deformed event horizon and calculate the tidal heating of the black hole, the rate at which it acquires mass as a result of its tidal interaction with the companion body.

  2. Verifying Red-Black Trees Paolo Baldan1

    E-Print Network [OSTI]

    Baldan, Paolo

    Verifying Red-Black Trees Paolo Baldan1 , Andrea Corradini2 , Javier Esparza3 , Tobias Heindel3,heindets,koenigba,koziouvi}@fmi.uni-stuttgart.de Abstract. We show how to verify the correctness of insertion of ele- ments into red-black trees--a form of balanced search trees--using anal- ysis techniques developed for graph rewriting. We first model red

  3. Accelerating and rotating black holes J. B. Griffiths1

    E-Print Network [OSTI]

    Accelerating and rotating black holes J. B. Griffiths1 and J. Podolsk´y2 1Department Abstract An exact solution of Einstein's equations which represents a pair of accelerating and rotating which explicitly contains the known special cases for either rotating or accelerating black holes

  4. Large rotating AdS black holes from fluid mechanics

    E-Print Network [OSTI]

    Sayantani Bhattacharyya; Subhaneil Lahiri; R. Loganayagam; Shiraz Minwalla

    2008-07-25T23:59:59.000Z

    We use the AdS/CFT correspondence to argue that large rotating black holes in global AdS(D) spaces are dual to stationary solutions of the relativistic Navier-Stokes equations on S**(D-2). Reading off the equation of state of this fluid from the thermodynamics of non-rotating black holes, we proceed to construct the nonlinear spinning solutions of fluid mechanics that are dual to rotating black holes. In all known examples, the thermodynamics and the local stress tensor of our solutions are in precise agreement with the thermodynamics and boundary stress tensor of the spinning black holes. Our fluid dynamical description applies to large non-extremal black holes as well as a class of large non-supersymmetric extremal black holes, but is never valid for supersymmetric black holes. Our results yield predictions for the thermodynamics of all large black holes in all theories of gravity on AdS spaces, for example, string theory on AdS(5) x S**5 and M theory on AdS(4) x S**7 and AdS(7) x S**4.

  5. Analysis of spherically symmetric black holes in Braneworld models

    E-Print Network [OSTI]

    A. B. Pavan

    2010-05-25T23:59:59.000Z

    Research on black holes and their physical proprieties has been active on last 90 years. With the appearance of the String Theory and the Braneworld models as alternative descriptions of our Universe, the interest on black holes, in these context, increased. In this work we studied black holes in Braneworld models. A class of spherically symmetric black holes is investigaded as well its stability under general perturbations. Thermodynamic proprieties and quasi-normal modes are discussed. The black holes studied are the SM (zero mass) and CFM solutions, obtained by Casadio {\\it et al.} and Bronnikov {\\it et al.}. The geometry of bulk is unknown. However the Campbell-Magaard Theorem guarantees the existence of a 5-dimensional solution in the bulk whose projection on the brane is the class of black holes considered. They are stable under scalar perturbations. Quasi-normal modes were observed in both models. The tail behavior of the perturbations is the same. The entropy upper bound of a body absorved by the black holes studied was calculated. This limit turned out to be independent of the black hole parameters.

  6. Pair Production of Topological anti de Sitter Black Holes

    E-Print Network [OSTI]

    R. B. Mann

    1996-07-28T23:59:59.000Z

    The pair creation of black holes with event horizons of non-trivial topology is described. The spacetimes are all limiting cases of the cosmological $C$ metric. They are generalizations of the $(2+1)$ dimensional black hole and have asymptotically anti de Sitter behaviour. Domain walls instantons can mediate their pair creation for a wide range of mass and charge.

  7. Synchronous Black Hole Search in Directed Graphs Adrian Kosowski

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Synchronous Black Hole Search in Directed Graphs Adrian Kosowski Alfredo Navarra Cristina M called black hole nodes, and once a robot enters in one of them, it is destroyed. The goal is to find supported by the Italian CNR Short-Term Mobility Program. A. Kosowski was supported Polish Ministry Grant N

  8. Modified Black Hole with Polar Jet and Vortex

    E-Print Network [OSTI]

    T. Tmmalm

    2001-12-06T23:59:59.000Z

    There are many models relating an accretion disk of Black Hole to jet outflow. The herein heuristic model describes the continuation of an external accretion disk to an internal accretion disk for less than Black Hole horizon, and subsequent polar jet outflow along polar axis out of polar vortex wherein the event horizon is no longer descriptive.

  9. Electromagnetic extraction of energy from Kerr black holes

    E-Print Network [OSTI]

    Isao Okamoto

    2005-06-14T23:59:59.000Z

    We elucidate the `right' process for energy extraction from Kerr black holes through `FFDE' magnetospheres, free from causality violation. It is shown that the magnetosphere of a Kerr black hole possesses the double-structure, consisting of the inner and outer magnetospheres with the pair-creation gap between them and with respective unipolar batteries at the inner and outer surfaces of the gap.

  10. "Black Box" EMC model for Power Electronics Converter Mikael Foissac

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    "Black Box" EMC model for Power Electronics Converter Mikael Foissac Grenoble Electrical be forecasted accurately, in order to avoid disturbance of the complete system. To quantify the EMC behaviour will then illustrate the method on a complete chopper cell. II. BLACK BOX EMC MODEL Any EMC analysis must account

  11. X] THEPROPAGATIONOF BLACK BASS IN PONDS. BY WILLIAM F. PAGE,

    E-Print Network [OSTI]

    X] THEPROPAGATIONOF BLACK BASS IN PONDS. BY WILLIAM F. PAGE, Superintendent U.S. Fish Commission to add to the fish supply by broadening the habitat of the black bass. But while fish-culturists were States, engaged in fish-culture were annually, at the period of the bass spawning, devoting every energy

  12. Structure and Mass Absorption of Hypothetical Terrestrial Black Holes

    E-Print Network [OSTI]

    A. P. VanDevender; J. Pace VanDevender

    2011-05-02T23:59:59.000Z

    The prospect of mini black holes, either primordial or in planned experiments at the Large Hadron Collider, interacting with the earth motivate us to examine how they may be detected and the scope of their impact on the earth. We propose that the more massive of these objects may gravitationally bind matter without significant absorption. Since the wave functions of gravitationally bound atoms orbiting a black hole are analogous to those of electrons around a nucleus, we call such an object the Gravitationally Equivalent of an Atom (GEA). Mini black holes are expected to lose mass through quantum evaporation, which has become well accepted on purely theoretical grounds. Since all attempts to directly observe x-rays from an evaporating black hole have failed, we examine the possibility of the inverse test: search for extant mini black holes by looking for emissions from matter bound in a GEA. If quantum evaporation does not occur, then miniature black holes left over from the early universe may be stable, contribute to dark matter, and in principle be detectable through emissions associated with the bound matter. We show that small black holes-with masses below \\sim10^12 kg-can bind matter without readily absorbing it into the black hole but the emissions are too weak to be detected from earth.

  13. Instabilities of (near) extremal rotating black holes in higher dimensions

    E-Print Network [OSTI]

    Stefan Hollands; Akihiro Ishibashi

    2014-08-04T23:59:59.000Z

    Recently, Durkee and Reall have conjectured a criterion for linear instability of rotating, extremal, asymptotically Minkowskian black holes in $d\\ge 4$ dimensions, such as the Myers-Perry black holes. They considered a certain elliptic operator, $\\cal A$, acting on symmetric traceless tensors intrinsic to the horizon. Based in part on numerical evidence, they suggested that if the lowest eigenvalue, $\\lambda$, of this operator is less than the critical value $-1/4$ ( called "effective BF-bound"), then the black hole is linearly unstable. In this paper, we prove their conjecture. Our proof uses a combination of methods such as (i) the "canonical energy method" of Hollands-Wald, (ii) algebraically special properties of the near horizon geometries associated with the black hole, and (iii) the structure of the (linearized) constraint equations. Our method of proof is also applicable to rotating, extremal asymptotically Anti-deSitter black holes. In that case, our methods show that "all" such black holes are unstable. Although we explicitly discuss in this paper only extremal black holes, we argue that our methods can be generalized straightforwardly to obtain the same results for "near" extremal black holes.

  14. Sequencing the Black Aspergilli species complex

    SciTech Connect (OSTI)

    Kuo, Alan; Salamov, Asaf; Zhou, Kemin; Otillar, Robert; Baker, Scott; Grigoriev, Igor

    2011-03-11T23:59:59.000Z

    The ~15 members of the Aspergillus section Nigri species complex (the "Black Aspergilli") are significant as platforms for bioenergy and bioindustrial technology, as members of soil microbial communities and players in the global carbon cycle, and as food processing and spoilage agents and agricultural toxigens. Despite their utility and ubiquity, the morphological and metabolic distinctiveness of the complex's members, and thus their taxonomy, is poorly defined. We are using short read pyrosequencing technology (Roche/454 and Illumina/Solexa) to rapidly scale up genomic and transcriptomic analysis of this species complex. To date we predict 11197 genes in Aspergillus niger, 11624 genes in A. carbonarius, and 10845 genes in A. aculeatus. A. aculeatus is our most recent genome, and was assembled primarily from 454-sequenced reads and annotated with the aid of >2 million 454 ESTs and >300 million Solexa ESTs. To most effectively deploy these very large numbers of ESTs we developed 2 novel methods for clustering the ESTs into assemblies. We have also developed a pipeline to propose orthologies and paralogies among genes in the species complex. In the near future we will apply these methods to additional species of Black Aspergilli that are currently in our sequencing pipeline.

  15. Light Loop Echoes and Blinking Black Holes

    E-Print Network [OSTI]

    Boyle, Latham

    2011-01-01T23:59:59.000Z

    Radiation emitted near a black hole reaches the observer by multiple paths; and when this radiation varies in time, the time-delays between the various paths generate a "blinking" effect in the observed light curve L(t) or its auto-correlation function xi(T)= . For the particularly important "face-on" configuration (in which the hole is viewed roughly along its spin axis, while the emission comes roughly from its equatorial plane -- e.g. from the inner edge of its accretion disk, or from the violent flash of a nearby/infalling star) we calculate the blinking in detail by computing the time delay Delta t_{j}(r,a) and magnification mu_{j}(r,a) of the jth path (j=1,2,3,...), relative to the primary path (j=0), as a function of the emission radius r and black hole spin 0

  16. Black holes in f(R) theories

    SciTech Connect (OSTI)

    Cruz-Dombriz, A. de la; Dobado, A.; Maroto, A. L. [Departamento de Fisica Teorica I, Universidad Complutense de Madrid, 28040 Madrid (Spain)

    2009-12-15T23:59:59.000Z

    In the context of f(R) theories of gravity, we address the problem of finding static and spherically symmetric black hole solutions. Several aspects of constant curvature solutions with and without electric charge are discussed. We also study the general case (without imposing constant curvature). Following a perturbative approach around the Einstein-Hilbert action, it is found that only solutions of the Schwarzschild-(anti) de Sitter type are present up to second order in perturbations. Explicit expressions for the effective cosmological constant are obtained in terms of the f(R) function. Finally, we have considered the thermodynamics of black holes in anti-de Sitter space-time and found that this kind of solution can only exist provided the theory satisfies R{sub 0}+f(R{sub 0})<0. Interestingly, this expression is related to the condition which guarantees the positivity of the effective Newton's constant in this type of theories. In addition, it also ensures that the thermodynamical properties in f(R) gravities are qualitatively similar to those of standard general relativity.

  17. Black Hole Instabilities and Exponential Growth

    E-Print Network [OSTI]

    Prabhu, Kartik

    2015-01-01T23:59:59.000Z

    Recently, a general analysis has been given of the stability with respect to axisymmetric perturbations of stationary-axisymmetric black holes and black branes in vacuum general relativity in arbitrary dimensions. It was shown that positivity of canonical energy on an appropriate space of perturbations is necessary and sufficient for stability. However, the notions of both "stability" and "instability" in this result are significantly weaker than one would like to obtain. In this paper, we prove that if a perturbation of the form $\\pounds_t \\delta g$---with $\\delta g$ a solution to the linearized Einstein equation---has negative canonical energy, then that perturbation must, in fact, grow exponentially in time. The key idea is to make use of the $t$- or ($t$-$\\phi$)-reflection isometry, $i$, of the background spacetime and decompose the initial data for perturbations into their odd and even parts under $i$. We then write the canonical energy as $\\mathscr E\\ = \\mathscr K + \\mathscr U$, where $\\mathscr K$ and $...

  18. Primordial black holes as biased tracers

    E-Print Network [OSTI]

    Tada, Yuichiro

    2015-01-01T23:59:59.000Z

    Primordial black holes (PBHs) are theoretical black holes which may be formed during the radiation dominant era and, basically, caused by the gravitational collapse of radiational overdensities. It has been well known that in the context of the structure formation in our Universe such collapsed objects, e.g., halos/galaxies, could be considered as bias tracers of underlying matter fluctuations and the halo/galaxy bias has been studied well. Employing a peak-background split picture which is known to be a useful tool to discuss the halo bias, we consider the large scale clustering behavior of the PBH and propose an almost mass-independent constraint to the scenario that dark matters (DMs) consist of PBHs. We consider the case where the statistics of the primordial curvature perturbations is almost Gaussian, but with small local-type non-Gaussianity. If PBHs account for the DM abundance, such a large scale clustering of PBHs behaves as nothing but the matter isocurvature perturbation and constrained strictly by...

  19. Black holes can have curly hair

    E-Print Network [OSTI]

    K. A. Bronnikov; O. B. Zaslavskii

    2008-05-29T23:59:59.000Z

    We study equilibrium conditions between a static, spherically symmetric black hole and classical matter in terms of the radial pressure to density ratio p_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\\to -1 as $u\\to u_h (the horizon), i.e., "vacuum" matter, for which \\rho(u_h) can be nonzero; (ii) w \\to -1/(1+2k) and \\rho \\sim (u-u_h)^k as u\\to u_h, where k>0 is a positive integer (w=-1/3 in the generic case k=1). A non-interacting 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.

  20. Experimental Signature for Black Hole Production in Neutrino Air Showers

    E-Print Network [OSTI]

    Luis Anchordoqui; Haim Goldberg

    2001-10-15T23:59:59.000Z

    The existence of extra degrees of freedom beyond the electroweak scale may allow the formation of black holes in nearly horizontal neutrino air showers. In this paper we examine the average properties of the light descendants of these black holes. Our analysis indicates that black hole decay gives rise to deeply penetrating showers with an electromagnetic component which differs substantially from that in conventional neutrino interactions, allowing a good characterization of the phenomenon against background. Naturally occurring black holes in horizontal neutrino showers could be detected and studied with the Auger air shower array. Since the expected black hole production rate at Auger is $> 1$ event/year, this cosmic ray observatory could be potentially powerful in probing models with extra dimensions and TeV-scale gravity.

  1. Quasinormal modes of test fields around regular black holes

    E-Print Network [OSTI]

    Bobir Toshmatov; Ahmadjon Abdujabbarov; Zden?k Stuchlk; Bobomurat Ahmedov

    2015-03-19T23:59:59.000Z

    We study scalar, electromagnetic and gravitational test fields in the Hayward, Bardeen and Ay\\'{o}n-Beato-Garc\\'{i}a regular black hole spacetimes and demonstrate that the test fields are stable in all these spacetimes. Using the sixth order WKB approximation of the linear "axial" perturbative scheme, we determine dependence of the quasinormal mode (QNM) frequencies on the characteristic parameters of the test fields and the spacetime charge parameters of the regular black holes. We give also the greybody factors, namely the transmission and reflection coefficients of scattered scalar, electromagnetic and gravitational waves. We show that damping of the QNMs in regular black hole spacetimes is suppressed in comparison to the case of Schwarzschild black holes, and increasing charge parameter of the regular black holes increases reflection and decreases transmission factor of incident waves for each of the test fields.

  2. Implications of a viscosity bound on black hole accretion

    E-Print Network [OSTI]

    Aninda Sinha; Banibrata Mukhopadhyay

    2012-02-13T23:59:59.000Z

    Motivated by the viscosity bound in gauge/gravity duality, we consider the ratio of shear viscosity (eta) to entropy density (s) in black hole accretion flows. We use both an ideal gas equation of state and the QCD equation of state obtained from lattice for the fluid accreting onto a Kerr black hole. The QCD equation of state is considered since the temperature of accreting matter is expected to approach 10^{12}K in certain hot flows. We find that in both the cases eta/s is small only for primordial black holes and several orders of magnitude larger than any known fluid for stellar and supermassive black holes. We show that a lower bound on the mass of primordial black holes leads to a lower bound on eta/s and vice versa. Finally we speculate that the Shakura-Sunyaev viscosity parameter should decrease with increasing density and/or temperatures.

  3. Hypervelocity binary stars: smoking gun of massive binary black holes

    E-Print Network [OSTI]

    Youjun Lu; Qingjuan Yu; D. N. C. Lin

    2007-07-22T23:59:59.000Z

    The hypervelocity stars recently found in the Galactic halo are expelled from the Galactic center through interactions between binary stars and the central massive black hole or between single stars and a hypothetical massive binary black hole. In this paper, we demonstrate that binary stars can be ejected out of the Galactic center with velocities up to 10^3 km/s, while preserving their integrity, through interactions with a massive binary black hole. Binary stars are unlikely to attain such high velocities via scattering by a single massive black hole or through any other mechanisms. Based on the above theoretical prediction, we propose a search for binary systems among the hypervelocity stars. Discovery of hypervelocity binary stars, even one, is a definitive evidence of the existence of a massive binary black hole in the Galactic center.

  4. Black Hole Hair Removal: Non-linear Analysis

    E-Print Network [OSTI]

    Dileep P. Jatkar; Ashoke Sen; Yogesh K. Srivastava

    2009-07-03T23:59:59.000Z

    BMPV black holes in flat transverse space and in Taub-NUT space have identical near horizon geometries but different microscopic degeneracies. It has been proposed that this difference can be accounted for by different contribution to the degeneracies of these black holes from hair modes, -- degrees of freedom living outside the horizon. In this paper we explicitly construct the hair modes of these two black holes as finite bosonic and fermionic deformations of the black hole solution satisfying the full non-linear equations of motion of supergravity and preserving the supersymmetry of the original solutions. Special care is taken to ensure that these solutions do not have any curvature singularity at the future horizon when viewed as the full ten dimensional geometry. We show that after removing the contribution due to the hair degrees of freedom from the microscopic partition function, the partition functions of the two black holes agree.

  5. Love isn't always black and white: understanding black-white interracial couples, their challenges, and their dyadic communication

    E-Print Network [OSTI]

    Wilson, Misty Michelle

    2009-05-15T23:59:59.000Z

    of their privileged position in society, whites life situations had never had necessitated that they learn about the black co-culture. The black partners also reported seeing the white community differently by understanding the nuances of racism at a deeper level...

  6. Hunter College Black Male Initiative-"Brothers for Excellence"-Summer Pipeline Programs Hunter College Black Male Initiative

    E-Print Network [OSTI]

    Qiu, Weigang

    Hunter College Black Male Initiative-"Brothers for Excellence"- Summer Pipeline Programs 1 Hunter College Black Male Initiative "Brothers for Excellence" Summer Pipeline Programs Table of Contents Page 11 Law Pipeline Programs 1 11 Graduate School, Earning a Ph.D., Conduct Research Pipeline Programs 24 16

  7. Coal water suspensions involving carbon black

    SciTech Connect (OSTI)

    Malone, D.P.; Thompson, D.G.

    1988-10-25T23:59:59.000Z

    This patent describes a composition comprising: about 65 to 80% by weight of coal particulates with a particle size distribution within 10% of the value calculated in accordance with a Funk distribution which assumes a maximum coal particle size of about 300 microns and minimum coal particle size of about 0.5 microns; about 0.2 to 2% by weight, as based upon the total weight of dry coal, of carbon black having a primary carbon particle size in the range of about 200 to about 900 Angstroms which primary carbon particles are simultaneously bound together to form primary reticulated chains having lengths in the range of about 500 to 30,000 Angstroms; a carrier liquid comprising 20 to 35 wt % water; and from 0.2 to 2.0 wt % of a dispersant selected from the group consisting of ammonium naphthalene sulfonic acid, hexadecyltrimethylammonium bromide, and ammonium lignosulfonate.

  8. Modeling the black hole excision problem

    SciTech Connect (OSTI)

    Szilagyi, B.; Winicour, J. [Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260 (United States); Albert Einstein Institute, Max Planck Gesellschaft, Am Muehlenberg 1, D-14476 Golm (Germany); Kreiss, H.-O. [Albert Einstein Institute, Max Planck Gesellschaft, Am Muehlenberg 1, D-14476 Golm (Germany); NADA, Royal Institute of Technology, 10044 Stockholm (Sweden)

    2005-05-15T23:59:59.000Z

    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.

  9. Char reactions during kraft black liquor pyrolysis

    SciTech Connect (OSTI)

    Frederick, W.J.; Sricharoenchaikul, V.; Reis, V.V. [Oregon State Univ., Corvallis, OR (United States)

    1995-12-01T23:59:59.000Z

    The pyrolysis characteristics of dried black liquor particles were investigated at high heating rates in a laminar entrained-flow reactor at temperatures of 600-1100{degrees}C. Primary pyrolysis of the organic fraction occurred very rapidly, in less 0.5 seconds. Char yields at the end or volatiles evolution were 58-72%. The decreased with increasing reactor temperature to 900{degrees}C but remained constant at higher temperatures. 35-65% of the fuel nitrogen was volatilized, nearly all in less than 0.5 s. Relatively little fuel nitrogen was evolved from the char. Significant alkali metal chloride volatization from the char occurred at all temperatures, while additional sodium volatilization became important above 900{degrees}C. Reduction of sulfur species in the char increased rapidly with increasing temperature. A temperature-dependent delay time in the onset of Na{sub 2}S formation was observed.

  10. Generalized uncertainty principle and black hole thermodynamics

    E-Print Network [OSTI]

    Sunandan Gangopadhyay; Abhijit Dutta; Anirban Saha

    2014-01-08T23:59:59.000Z

    We study the Schwarzschild and Reissner-Nordstr\\"{o}m black hole thermodynamics using the simplest form of the generalized uncertainty principle (GUP) proposed in the literature. The expressions for the mass-temperature relation, heat capacity and entropy are obtained in both cases from which the critical and remnant masses are computed. Our results are exact and reveal that these masses are identical and larger than the so called singular mass for which the thermodynamics quantities become ill-defined. The expression for the entropy reveals the well known area theorem in terms of the horizon area in both cases upto leading order corrections from GUP. The area theorem written in terms of a new variable which can be interpreted as the reduced horizon area arises only when the computation is carried out to the next higher order correction from GUP.

  11. Polymeric Quantization and Black Hole Thermodynamics

    E-Print Network [OSTI]

    M. A. Gorji; Kourosh Nozari; B. Vakili

    2014-05-18T23:59:59.000Z

    Polymer quantization is a non-standard representation of the quantum mechanics that inspired by loop quantum gravity. To study the associated statistical mechanics, one needs to find microstates' energies which are eigenvalues of the Hamiltonian operator in the polymer framework. But, this is not an easy task at all since the Hamiltonian takes a nonlinear form in polymer picture. In this paper, we introduce a semiclassical method in which it is not necessary to solve the eigenvalue problem. Instead, we work with the classical Hamiltonian function and the deformed density of states in the polymeric phase space. Implementing this method, we obtain the canonical partition function for the polymerized systems and we show that our results are in good agreement with those arising from full quantum considerations. Using the partition function, we study the thermodynamics of quantum Schwarzschild black hole and we obtain corrections to the Bekenstein-Hawking entropy due to loop quantum gravity effects.

  12. The Galactic Center Black Hole Laboratory

    E-Print Network [OSTI]

    Eckart, A; Valencia-S., M; Straubmeier, C; Zensus, J A; Karas, V; Kunneriath, D; Alberdi, A; Sabha, N; Schdel, R; Puetzfeld, D

    2015-01-01T23:59:59.000Z

    The super-massive 4 million solar mass black hole Sagittarius~A* (SgrA*) shows flare emission from the millimeter to the X-ray domain. A detailed analysis of the infrared light curves allows us to address the accretion phenomenon in a statistical way. The analysis shows that the near-infrared flare amplitudes are dominated by a single state power law, with the low states in SgrA* limited by confusion through the unresolved stellar background. There are several dusty objects in the immediate vicinity of SgrA*. The source G2/DSO is one of them. Its nature is unclear. It may be comparable to similar stellar dusty sources in the region or may consist predominantly of gas and dust. In this case a particularly enhanced accretion activity onto SgrA* may be expected in the near future. Here the interpretation of recent data and ongoing observations are discussed.

  13. Horizon dynamics of distorted rotating black holes

    E-Print Network [OSTI]

    Tony Chu; Harald P. Pfeiffer; Michael I. Cohen

    2011-04-28T23:59:59.000Z

    We present numerical simulations of a Kerr black hole perturbed by a pulse of ingoing gravitational radiation. For strong perturbations we find up to five concentric marginally outer trapped surfaces. These trapped surfaces appear and disappear in pairs, so that the total number of such surfaces at any given time is odd. The world tubes traced out by the marginally outer trapped surfaces are found to be spacelike during the highly dynamical regime, approaching a null hypersurface at early and late times. We analyze the structure of these marginally trapped tubes in the context of the dynamical horizon formalism, computing the expansion of outgoing and incoming null geodesics, as well as evaluating the dynamical horizon flux law and the angular momentum flux law. Finally, we compute the event horizon. The event horizon is well-behaved and approaches the apparent horizon before and after the highly dynamical regime. No new generators enter the event horizon during the simulation.

  14. Bubbling the Newly Grown Black Ring Hair

    E-Print Network [OSTI]

    Orestis Vasilakis

    2012-02-08T23:59:59.000Z

    New families of BPS black ring solutions with four electric and four dipole magnetic charges have recently been explicitly constructed and uplifted to M-theory. These solutions were found to belong to a CFT with central charge different compared to the one of the STU model. Because of their importance to AdS/CFT, here we give the microstate description of these geometries in terms of topological bubbles and supertubes. The fourth charge results in an additional flux through the topological cycles that resolve the brane singularities. The analog of these solutions in the IIB frame yield a generalized regular supertube with three electric charges and one dipole charge. Direct comparison is also made with the previously-known bubbled geometries.

  15. Higgs Boson Production from Black Holes at the LHC

    E-Print Network [OSTI]

    Gouranga C. Nayak; J. Smith

    2006-06-09T23:59:59.000Z

    If the fundamental Planck scale is near a TeV, then TeV scale black holes should be produced in proton-proton collisions at the LHC where \\sqrt{s} = 14 TeV. As the temperature of the black holes can be ~ 1 TeV we also expect production of Higgs bosons from them via Hawking radiation. This is a different production mode for the Higgs boson, which would normally be produced via direct pQCD parton fusion processes. In this paper we compare total cross sections and transverse momentum distributions d\\sigma/dp_T for Higgs production from black holes at the LHC with those from direct parton fusion processes at next-to-next-to-leading order and next-to-leading order respectively. We find that the Higgs production from black holes can be larger or smaller than the direct pQCD production depending upon the Planck mass and black hole mass. We also find that d\\sigma/dp_T of Higgs production from black holes increases as a function of p_T which is in sharp contrast with the pQCD predictions where d\\sigma/dp_T decreases so we suggest that the measurement of an increase in d\\sigma/dp_T as p_T increases for Higgs (or any other heavy particle) production can be a useful signature for black holes at the LHC.

  16. Black Holes with Primary Hair in gauged N=8 Supergravity

    E-Print Network [OSTI]

    Andres Anabalon; Fabrizio Canfora; Alex Giacomini; Julio Oliva

    2012-03-29T23:59:59.000Z

    In this paper, we analyze the static solutions for the $U(1)^{4}$ consistent truncation of the maximally supersymmetric gauged supergravity in four dimensions. Using a new parametrization of the known solutions it is shown that for fixed charges there exist three possible black hole configurations according to the pattern of symmetry breaking of the (scalars sector of the) Lagrangian. Namely a black hole without scalar fields, a black hole with a primary hair and a black hole with a secondary hair respectively. This is the first, exact, example of a black hole with a primary scalar hair, where both the black hole and the scalar fields are regular on and outside the horizon. The configurations with secondary and primary hair can be interpreted as a spontaneous symmetry breaking of discrete permutation and reflection symmetries of the action. It is shown that there exist a triple point in the thermodynamic phase space where the three solution coexist. The corresponding phase transitions are discussed and the free energies are written explicitly as function of the thermodynamic coordinates in the uncharged case. In the charged case the free energies of the primary hair and the hairless black hole are also given as functions of the thermodynamic coordinates.

  17. No-hair theorem for Black Holes in Astrophysical Environments

    E-Print Network [OSTI]

    Grlebeck, Norman

    2015-01-01T23:59:59.000Z

    According to the no-hair theorem, static black holes are described by a Schwarzschild spacetime provided there are no other sources of the gravitational field. This requirement, however, is in astrophysical realistic scenarios often violated, e.g., if the black hole is part of a binary system or if it is surrounded by an accretion disk. In these cases, the black hole is distorted due to tidal forces. Nonetheless, the subsequent formulation of the no-hair theorem holds: The contribution of the distorted black hole to the multipole moments that describe the gravitational field close to infinity and, thus, all sources is that of a Schwarzschild black hole. It still has no hair. This implies that there is no multipole moment induced in the black hole and that its second Love numbers, which measure some aspects of the distortion, vanish as was already shown in approximations to general relativity. But here we prove this property for astrophysical relevant black holes in full general relativity.

  18. Scalar emission in a rotating Gdel black hole

    E-Print Network [OSTI]

    Songbai Chen; Bin Wang; Jiliang Jing

    2008-08-23T23:59:59.000Z

    We study the absorption probability and Hawking radiation of the scalar field in the rotating G\\"{o}del black hole in minimal five-dimensional gauged supergravity. We find that G\\"{o}del parameter $j$ imprints in the greybody factor and Hawking radiation. It plays a different role from the angular momentum of the black hole in the Hawking radiation and super-radiance. These information can help us know more about rotating G\\"{o}del black holes in minimal five-dimensional gauged supergravity.

  19. Thermodynamics of an Evaporating Schwarzschild Black Hole in Noncommutative Space

    E-Print Network [OSTI]

    Kourosh Nozari; Behnaz Fazlpour

    2007-01-14T23:59:59.000Z

    We investigate the effects of space noncommutativity and the generalized uncertainty principle on the thermodynamics of a radiating Schwarzschild black hole. We show that evaporation process is in such a way that black hole reaches to a maximum temperature before its final stage of evolution and then cools down to a nonsingular remnant with zero temperature and entropy. We compare our results with more reliable results of string theory. This comparison Shows that GUP and space noncommutativity are similar concepts at least from view point of black hole thermodynamics.

  20. Safeguards Approaches for Black Box Processes or Facilities

    SciTech Connect (OSTI)

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

    2013-09-25T23:59:59.000Z

    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.

  1. Geodesic Motion in the (Charged) Doubly Spinning Black Ring Spacetime

    E-Print Network [OSTI]

    Saskia Grunau; Valeria Kagramanova; Jutta Kunz

    2012-12-03T23:59:59.000Z

    In this article we analyze the geodesics of test particles and light in the five dimensional (charged) doubly spinning black ring spacetime. Apparently it is not possible to separate the Hamilton-Jacobi-equation for (charged) doubly spinning black rings in general, so we concentrate on special cases: null geodesics in the ergosphere and geodesics on the two rotational axes of the (charged) doubly spinning black ring. We present analytical solutions to the geodesic equations for these special cases. Using effective potential techniques we study the motion of test particles and light and discuss the corresponding orbits.

  2. Thermal processing of black liquor from alkaline straw pulping

    SciTech Connect (OSTI)

    Sanchez, J.L.; Garcia, L.; Gea, G.; Bilbao, R.; Arauzo, J. [Univ. of Zaragoza (Spain)

    1996-12-31T23:59:59.000Z

    Black liquor is the wastewater from the cooking of wood or straw in the production of pulp and paper. Nowadays new processes are being investigated as alternatives to the traditional recovery boiler used for black liquor treatment. One of the processes which appears to be more promising is gasification, for which further research is needed for its full industrial implementation. There is not much data about the behavior of soda black liquors from straw cooking in the literature. Therefore the thermal decomposition of one of these liquors has been studied in a thermobalance, in inert (N{sub 2}) atmosphere. The kinetic constants from isothermal experiments have been obtained.

  3. Inferring black hole charge from backscattered electromagnetic radiation

    E-Print Network [OSTI]

    Lus C. B. Crispino; Sam R. Dolan; Atsushi Higuchi; Ednilton S. de Oliveira

    2014-09-16T23:59:59.000Z

    We compute the scattering cross section of Reissner-Nordstr\\"om black holes for the case of an incident electromagnetic wave. We describe how scattering is affected by both the conversion of electromagnetic to gravitational radiation, and the parity-dependence of phase shifts induced by the black hole charge. The latter effect creates a helicity-reversed scattering amplitude that is non-zero in the backward direction. We show that from the character of the electromagnetic wave scattered in the backward direction it is possible, in principle, to infer if a static black hole is charged.

  4. Hawking temperature of rotating charged black strings from tunneling

    SciTech Connect (OSTI)

    Ahmed, Jamil; Saifullah, K., E-mail: jamil_051@yahoo.com, E-mail: saifullah@qau.edu.pk [Department of Mathematics, Quaid-i-Azam University, Islamabad (Pakistan)

    2011-11-01T23:59:59.000Z

    Thermal radiations from spherically symmetric black holes have been studied from the point of view of quantum tunneling. In this paper we extend this approach to study radiation of fermions from charged and rotating black strings. Using WKB approximation and Hamilton-Jacobi method we work out the tunneling probabilities of incoming and outgoing fermions and find the correct Hawking temperature for these objects. We show that in appropriate limits the results reduce to those for the uncharged and non-rotating black strings.

  5. String black hole: Can it be a particle accelerator ?

    E-Print Network [OSTI]

    Sharmanthie Fernando

    2014-08-21T23:59:59.000Z

    In this paper we have studied the possibility of the center-of-mass energy of two particles colliding near the horizon of a static charged black hole in string theory. Various cases corresponding to the electric charge and the angular momentum of the particles were considered. The studies were done for the general black hole as well as for the extreme black hole. There were two scenarios where the center-of-mass energy reach very large values if the appropriate properties of the particles are chosen.

  6. Accretion onto a black hole in a string cloud background

    E-Print Network [OSTI]

    Apratim Ganguly; Sushant G. Ghosh; Sunil D. Maharaj

    2014-09-28T23:59:59.000Z

    We examine the accretion process onto the black hole with a string cloud background, where the horizon of the black hole has an enlarged radius $r_H=2 M/(1-\\alpha)$, due to the string cloud parameter $\\alpha\\; (0 \\leq \\alpha cloud parameter $\\alpha$. We also find the gas compression ratios and temperature profiles below the accretion radius and at the event horizon. It is shown that the mass accretion rate, for both the relativistic and the non-relativistic fluid by a black hole in the string cloud model, increases with increase in $\\alpha$.

  7. Phenomenological Description of the Interior of the Schwarzschild Black Hole

    E-Print Network [OSTI]

    Hikaru Kawai; Yuki Yokokura

    2014-09-19T23:59:59.000Z

    We discuss a sufficiently large 4-dimensional Schwarzschild black hole which is in equilibrium with a heat bath. In other words, we consider a black hole which has grown up from a small one in the heat bath adiabatically. We express the metric of the interior of the black hole in terms of two functions: One is the intensity of the Hawking radiation, and the other is the ratio between the radiation energy and the pressure in the radial direction. Especially in the case of conformal matters we check that it is a self-consistent solution of the semi-classical Einstein equation, $G_{\\mu\

  8. Black holes and the absorption rate of cosmological scalar fields

    E-Print Network [OSTI]

    L. Arturo Urena-Lopez; Lizbeth M. Fernandez

    2011-07-15T23:59:59.000Z

    We study the absorption of a massless scalar field by a static black hole. Using the continuity equation that arises from the Klein-Gordon equation, it is possible to define a normalized absorption rate $\\Gamma(t)$ for the scalar field as it falls into the black hole. It is found that the absorption mainly depends upon the characteristics wavelengths involved in the physical system: the mean wavenumber and the width of the wave packet, but that it is insensitive to the scalar field's strength. By taking a limiting procedure, we determine the minimum absorption fraction of the scalar field's mass by the black hole, which is around 50%.

  9. Hawking Radiation by Kerr Black Holes and Conformal Symmetry

    SciTech Connect (OSTI)

    Agullo, Ivan; Parker, Leonard [Physics Department, University of Wisconsin-Milwaukee, P.O. Box 413, Milwaukee, Wisconsin 53201 (United States); Navarro-Salas, Jose [Departamento de Fisica Teorica and IFIC, Centro Mixto Universidad de Valencia-CSIC. Facultad de Fisica, Universidad de Valencia, Burjassot-46100, Valencia (Spain); Olmo, Gonzalo J. [Instituto de Estructura de la Materia, CSIC, Serrano 121, 28006 Madrid (Spain)

    2010-11-19T23:59:59.000Z

    The exponential blueshift associated with the event horizon of a black hole makes conformal symmetry play a fundamental role in accounting for its thermal properties. Using a derivation based on two-point functions, we show that the full spectrum of thermal radiation of scalar particles by Kerr black holes can be explicitly derived on the basis of a conformal symmetry arising in the wave equation near the horizon. The simplicity of our approach emphasizes the depth of the connection between conformal symmetry and black hole radiance.

  10. Black California Dreamin': The Crises of California's African-American Communities

    E-Print Network [OSTI]

    Woods, Clyde

    2012-01-01T23:59:59.000Z

    Palo Alto. 19 Demographically, South Bay black pioneers had to work together because their population

  11. Merton's Status Exchange Theory and Husband-Wife Education Differences in Black Intermarriage

    E-Print Network [OSTI]

    Malone, Danny E.

    2013-10-23T23:59:59.000Z

    ........................................................................................................ 86 REFERENCES ................................................................................................................. 88 vii LIST OF FIGURES Page Figure 5-1. Histogram of Husband-Wife Education Difference Residuals... that a white womans black husband does so. These findings would suggest status exchange support for black men, not black women. In their case, endogamous intermarriage is taking place where the level of education is similar among black-white marriages...

  12. The 3-Sphere and the Bicycling Black Rings Event Horizon The 3-Sphere and the Bicycling

    E-Print Network [OSTI]

    Bengtsson, Ingemar

    The 3-Sphere and the Bicycling Black Rings Event Horizon #12;#12;The 3-Sphere and the Bicycling that "the bicycling black rings" are a admissible solution to the event horizon of black holes in 4 is to develop a method of visualising the bicycling black rings and other four-dimensional objects. In the end

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

    SciTech Connect (OSTI)

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

    1987-10-01T23:59:59.000Z

    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.

  14. Supermassive Black Holes at the Center of Galaxies

    E-Print Network [OSTI]

    Christopher J. Greenwood

    2005-12-13T23:59:59.000Z

    This was my final paper for the AST 308 Galaxies class at Michigan State University. Using many sources I was able to compile a moderate amount of information concerning the evidence for, and the formation of Supermassive Black Holes.

  15. Quantum Emission from Two-Dimensional Black Holes

    E-Print Network [OSTI]

    Steven B. Giddings; W. M. Nelson

    2009-11-27T23:59:59.000Z

    We investigate Hawking radiation from two-dimensional dilatonic black holes using standard quantization techniques. In the background of a collapsing black hole solution the Bogoliubov coefficients can be exactly determined. In the regime after the black hole has settled down to an `equilibrium' state but before the backreaction becomes important these give the known result of a thermal distribution of Hawking radiation at temperature lambda/(2pi). The density matrix is computed in this regime and shown to be purely thermal. Similar techniques can be used to derive the stress tensor. The resulting expression agrees with the derivation based on the conformal anomaly and can be used to incorporate the backreaction. Corrections to the thermal density matrix are also examined, and it is argued that to leading order in perturbation theory the effect of the backreaction is to modify the Bogoliubov transformation, but not in a way that restores information lost to the black holes.

  16. The Energy for 2+1 Dimensional Black Hole Solutions

    E-Print Network [OSTI]

    I-Ching Yang; Irina Radinschi

    2006-11-05T23:59:59.000Z

    The energy distributions of four 2+1 dimensional black hole solutions were obtained by using the Einstein and M{\\o}ller energy-momentum complexes. while $r \\to \\infty$, the energy distributions of these four solutions become divergence.

  17. Black Hills Energy (Gas)- Residential New Construction Rebate Program

    Broader source: Energy.gov [DOE]

    Black Hills Energy offers new construction rebates for home builders in the eligible service area. Rebates between $800 and $5,000 are available for a range of efficiency measures incorporated into...

  18. Magnetic wormholes and black universes with invisible ghosts

    E-Print Network [OSTI]

    Bronnikov, K A

    2015-01-01T23:59:59.000Z

    We construct explicit examples of globally regular static, spherically symmetric solutions in general relativity with scalar and electromagnetic fields describing traversable wormholes with flat and AdS asymptotics and regular black holes, in particular, black universes. (A black universe is a regular black hole with an expanding, asymptotically isotropic space-time beyond the horizon.) The existence of such objects requires invoking scalars with negative kinetic energy ("phantoms", or "ghosts"), which are not observed under usual physical conditions. To account for that, the so-called "trapped ghosts" were previously introduced, i.e., scalars whose kinetic energy is only negative in a restricted strong-field region of space-time and positive outside it. This approach leads to certain problems, including instability (as is illustrated here by derivation of an effective potential for spherical pertubations of such systems). In this paper, we use for model construction what we call "invisible ghosts", i.e., pha...

  19. Black Pine Engineering Wins Clean Energy Trust Clean Energy Challenge...

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

    steam loss. According to Black Pine, the technology can boost power generation at geothermal plants by 8% and increase revenue by more than 280,000 per year per well....

  20. Demonstration of Black Liquor Gasification at Big Island

    SciTech Connect (OSTI)

    Robert DeCarrera

    2007-04-14T23:59:59.000Z

    This Final Technical Report provides an account of the project for the demonstration of Black Liquor Gasification at Georgia-Pacific LLC's Big Island, VA facility. This report covers the period from May 5, 2000 through November 30, 2006.

  1. Lovelock black holes in a string cloud background

    E-Print Network [OSTI]

    Tae-Hun Lee; Dharmanand Baboolal; Sushant G. Ghosh

    2014-09-12T23:59:59.000Z

    We present an exact static, spherically symmetric black hole solution to the third order Lovelock gravity with a string cloud background in seven dimensions for the special case when the second and third order Lovelock coefficients are related via $\\tilde{\\alpha}^2_2=3\\tilde{\\alpha}_3\\;(\\equiv\\alpha^2)$. Further, we examine thermodynamic properties of this black hole to obtain exact expressions for mass, temperature, entropy and also perform the thermodynamic stability analysis. We see that a string cloud background makes a profound influence on horizon structure, thermodynamic properties and the stability of black holes. Interestingly, the entropy of the black hole is unaffected due to a string cloud background. However, the critical solution for thermodynamic stability is being affected by a string cloud background.

  2. 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.

  3. asiatic black bear: Topics by E-print Network

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

    is described by a collapsing prho FRW cosmology. We conjecture that the black hole fluid is invariant under the conformal Killing symmetry of this metric, so that the final...

  4. asiatic black bears: Topics by E-print Network

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

    is described by a collapsing prho FRW cosmology. We conjecture that the black hole fluid is invariant under the conformal Killing symmetry of this metric, so that the final...

  5. In Celebration of Black History Month, Energy Secretary Moniz...

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

    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 Black History Month, Energy...

  6. Search for gravitational waves from intermediate mass binary black holes

    E-Print Network [OSTI]

    Barsotti, Lisa

    We present the results of a weakly modeled burst search for gravitational waves from mergers of nonspinning intermediate mass black holes in the total mass range 100450??M? and with the component mass ratios between 1?1 ...

  7. Black holes and the quark-gluon plasma

    E-Print Network [OSTI]

    George Siopsis

    2009-01-26T23:59:59.000Z

    I discuss the possibility that the quark-gluon plasma at strong coupling admits a description in terms of a black hole in asymptotically anti-de Sitter space.

  8. Vortex hair on AdS black holes

    E-Print Network [OSTI]

    Gregory, Ruth; Kubiznak, David; Mann, Robert B; Wills, Danielle

    2014-01-01T23:59:59.000Z

    We analyse vortex hair for charged rotating asymptotically AdS black holes in the abelian Higgs model. We give analytical and numerical arguments to show how the vortex interacts with the horizon of the black hole, and how the solution extends to the boundary. The solution is very close to the corresponding asymptotically flat vortex, once one transforms to a frame that is non-rotating at the boundary. We show that there is a Meissner effect for extremal black holes, with the vortex flux being expelled from sufficiently small black holes. The phase transition is shown to be first order in the presence of rotation, but second order without rotation. We comment on applications to holography.

  9. On the Quantum-Corrected Black Hole Thermodynamics

    E-Print Network [OSTI]

    Kourosh Nozari; S. Hamid Mehdipour

    2006-01-15T23:59:59.000Z

    Bekenstein-Hawking Black hole thermodynamics should be corrected to incorporate quantum gravitational effects. Generalized Uncertainty Principle(GUP) provides a perturbational framework to perform such modifications. In this paper we consider the most general form of GUP to find black holes thermodynamics in microcanonical ensemble. Our calculation shows that there is no logarithmic pre-factor in perturbational expansion of entropy. This feature will solve part of controversies in literatures regarding existence or vanishing of this pre-factor.

  10. Renormalization and black hole entropy in Loop Quantum Gravity

    E-Print Network [OSTI]

    Ted Jacobson

    2007-08-25T23:59:59.000Z

    Microscopic state counting for a black hole in Loop Quantum Gravity yields a result proportional to horizon area, and inversely proportional to Newton's constant and the Immirzi parameter. It is argued here that before this result can be compared to the Bekenstein-Hawking entropy of a macroscopic black hole, the scale dependence of both Newton's constant and the area must be accounted for. The two entropies could then agree for any value of the Immirzi parameter, if a certain renormalization property holds.

  11. On the energy of Ho?ava-Lifshitz black holes

    E-Print Network [OSTI]

    I. Radinschi; F. Rahaman; A. Banerjee

    2011-02-10T23:59:59.000Z

    In this paper we calculate the energy distribution of the Mu-in Park, Kehagias-Sfetsos (KS) and L\\"u, Mei and Pope (LMP) black holes in the Ho\\v{r}ava-Lifshitz theory of gravity. These black hole solutions correspond to the standard Einstein-Hilbert action in the infrared limit. For our calculations we use the Einstein and M{\\o}ller prescriptions. Various limiting and particular cases are also discussed.

  12. 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)

    1997-05-01T23:59:59.000Z

    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.

  13. Embeddings of the black holes in a flat space

    E-Print Network [OSTI]

    A. A. Sheykin; D. A. Grad; S. A. Paston

    2014-01-30T23:59:59.000Z

    We study the explicit embeddings of static black holes. We obtain two new minimal embeddings of the Schwarzchild-de Sitter metric which smoothly cover both horizons of this metric. The lines of time for these embeddings are more complicated than hyperbolas. Also we shortly discuss the possibility of using non-hyperbolic embeddings for calculation of the black hole Hawking temperature in the Deser and Levin approach.

  14. Electromagnetic quasinormal modes of D-dimensional black holes

    E-Print Network [OSTI]

    A. Lpez-Ortega

    2006-11-02T23:59:59.000Z

    Using the monodromy method we calculate the asymptotic quasinormal (QN) frequencies of an electromagnetic field moving in D-dimensional Schwarzschild and Schwarzschild de Sitter (SdS) black holes ($D\\geq 4$). For the D-dimensional Schwarzschild anti-de Sitter (SadS) black hole we also compute these frequencies with a similar method. Moreover, we calculate the electromagnetic normal modes of the D-dimensional anti-de Sitter (AdS) spacetime.

  15. Statistical Physics of 3D Hairy Black Holes

    E-Print Network [OSTI]

    A. Belhaj; M. Chabab; H. EL Moumni; K. Masmar; M. B. Sedra

    2014-12-29T23:59:59.000Z

    We investigate the statistical behaviors of 3D hairy black holes in the presence of a scalar field. The present study is made in terms of two relevant parameters: rotation parameter a and B parameter related to the scalar field. More precisely, we compute various statistical quantities including the partition function for non-charged and charged black hole solutions. Using a partition function calculation, we show that the probability is independent of a and B parameters.

  16. Electrochemical treatment of black liquor from straw pulping

    SciTech Connect (OSTI)

    Blanco, M.A.; Negro, C.; Tijero, J. [Complutense Univ., Madrid (Spain)] [and others

    1996-11-01T23:59:59.000Z

    The conventional black liquor regeneration process is not always suitable for pulping plants of nonwood fibers due to the unfavorable ratio of organic to inorganic solids. This paper presents an alternative treatment based on an electrolysis process of the soda black liquor from straw pulping. This alternative method minimizes the environmental impact by recovering the caustic at the same time that the liquor is acidified, which favors the later separation of the lignin.

  17. Topological aspect of black hole with Skyrme hair

    E-Print Network [OSTI]

    Yi-Shi Duan; Xin-Hui Zhang; Li Zhao

    2007-03-19T23:59:59.000Z

    Based on the $\\phi$-mapping topological current theory, we show that the presence of the black hole leaves fractional baryon charge outside the horizon in the Einstein-Skyrme theory. A topological current is derived from the Einstein-Skyrme system, which corresponds to the monopoles around the black hole. The branch process (splitting, merging and intersection) is simply discussed during the evolution of the monopoles.

  18. Towards a characterization of fields leading to black hole hair

    E-Print Network [OSTI]

    Narayan Banerjee; Somasri Sen

    2013-07-05T23:59:59.000Z

    In the present work, it is shown that an asymptotically flat spherical black hole can have a nontrivial signature of any field for an exterior observer if the energy momentum tensor of the corresponding field is either tracefree or if the trace falls off at least as rapidly as inverse cube of the radial distance. In the absence of a general No Hair Theorem, this result can provide a characterization of the fields leading to black hole hair.

  19. Thermodynamic properties of asymptotically ReissnerNordstrm black holes

    SciTech Connect (OSTI)

    Hendi, S.H., E-mail: hendi@shirazu.ac.ir

    2014-07-15T23:59:59.000Z

    Motivated by possible relation between BornInfeld type nonlinear electrodynamics and an effective low-energy action of open string theory, asymptotically ReissnerNordstrm black holes whose electric field is described by a nonlinear electrodynamics (NLED) are studied. We take into account a four dimensional topological static black hole ansatz and solve the field equations, exactly, in terms of the NLED as a matter field. The main goal of this paper is investigation of thermodynamic properties of the obtained black holes. Moreover, we calculate the heat capacity and find that the nonlinearity affects the minimum size of stable black holes. We also use Legendre-invariant metric proposed by Quevedo to obtain scalar curvature divergences. We find that the singularities of the Ricci scalar in Geometrothermodynamics (GTD) method take place at the Davies points. -- Highlights: We examine the thermodynamical properties of black holes in Einstein gravity with nonlinear electrodynamics. We investigate thermodynamic stability and discuss about the size of stable black holes. We obtain analytical solutions of higher dimensional theory.

  20. Simulating merging binary black holes with nearly extremal spins

    SciTech Connect (OSTI)

    Lovelace, Geoffrey [Center for Radiophysics and Space Research, Cornell University, Ithaca, New York, 14853 (United States); Scheel, Mark A.; Szilagyi, Bela [Theoretical Astrophysics 350-17, California Institute of Technology, Pasadena, California 91125 (United States)

    2011-01-15T23:59:59.000Z

    Astrophysically realistic black holes may have spins that are nearly extremal (i.e., close to 1 in dimensionless units). Numerical simulations of binary black holes are important tools both for calibrating analytical templates for gravitational-wave detection and for exploring the nonlinear dynamics of curved spacetime. However, all previous simulations of binary-black-hole inspiral, merger, and ringdown have been limited by an apparently insurmountable barrier: the merging holes' spins could not exceed 0.93, which is still a long way from the maximum possible value in terms of the physical effects of the spin. In this paper, we surpass this limit for the first time, opening the way to explore numerically the behavior of merging, nearly extremal black holes. Specifically, using an improved initial-data method suitable for binary black holes with nearly extremal spins, we simulate the inspiral (through 12.5 orbits), merger and ringdown of two equal-mass black holes with equal spins of magnitude 0.95 antialigned with the orbital angular momentum.

  1. Hawking Radiation of a Charged Black Hole in Quantum Gravity

    E-Print Network [OSTI]

    Ichiro Oda

    2015-03-18T23:59:59.000Z

    We study black hole radiation of a Reissner-Nordstrom black hole with an electric charge in the framework of quantum gravity. Based on a canonical quantization for a spherically symmetric geometry, under physically plausible assumptions, we solve the Wheeler-De Witt equation in the regions not only between the outer apparent horizon and the spatial infinity but also between the spacetime singularity and the inner apparent horizon, and then show that the mass loss rate of an evaporating black hole due to thermal radiation agrees with the semiclassical result when we choose an integration constant properly by physical reasoning. Furthermore, we also solve the Wheeler-De Witt equation in the region between the inner Cauchy horizon and the outer apparent horizon, and show that the mass loss rate of an evaporating black hole has the same expression. The present study is the natural generalization of the case of a Schwarzschild black hole to that of a charged Reissner-Nordstrom black hole.

  2. Black Hole Remnants and the Information Loss Paradox

    E-Print Network [OSTI]

    Pisin Chen; Yen Chin Ong; Dong-han Yeom

    2015-01-30T23:59:59.000Z

    Forty years after the discovery of Hawking radiation, its exact nature remains elusive. If Hawking radiation does not carry any information out from the ever shrinking black hole, it seems that unitarity is violated once the black hole completely evaporates. On the other hand, attempts to recover information via quantum entanglement lead to the firewall controversy. Amid the confusions, the possibility that black hole evaporation stops with a "remnant" has remained unpopular and is often dismissed due to some "undesired properties" of such an object. Nevertheless, as in any scientific debate, the pros and cons of any proposal must be carefully scrutinized. We fill in the void of the literature by providing a timely review of various types of black hole remnants, and provide some new thoughts regarding the challenges that black hole remnants face in the context of information loss paradox and its latest incarnation, namely the firewall controversy. The importance of understanding the role of curvature singularity is also emphasized, after all there remains a possibility that singularity cannot be cured even by quantum gravity. In this context a black hole remnant conveniently serves as a cosmic censor. We conclude that a remnant remains a possible end state of Hawking evaporation, and if it contains large interior geometry, may help to ameliorate information loss and the firewall paradox. We hope that this will raise some interests in the community to investigate remnants more critically but also more thoroughly.

  3. Proceedings of the black liquor research program review fifth meeting

    SciTech Connect (OSTI)

    Not Available

    1988-09-01T23:59:59.000Z

    On June 14--17, 1988 the participants and invited guests of the Cooperative Program in Kraft Recovery gathered in Charleston, South Carolina, to review progress on four major black liquor research programs being executed at the Institute of Paper Chemistry, the University of Maine, the National Bureau of Standards, and the University of Florida. These programs include: (1) Black Liquor Properties; (2) Black Liquor Droplet Formation; (3) Black Liquor Nozzle Evaluation; and (4) Black Liquor Combustion. In addition to the objectives of previous meetings, this meeting made a direct attempt to gather ideas on how to improve our ability to move from new technology concepts to commercial implementation. Also attached is the agenda for the Charleston meeting. The first two days were involved with updates and reviews of the four major black liquor programs. A half day was spent discussing pathways to implementation and developing thoughts on what industry, DOE and academia could do to facilitate commercial implementation of the research results. This publication is a summary of the presentations made in Charleston and the industry responses to the research work. Readers are cautioned that the contents are in-progress updates on the status of the research and do not represent referred technical papers. Any questions regarding the content should be referred to the principal investigators of the project.

  4. Hawking Radiation of a Charged Black Hole in Quantum Gravity

    E-Print Network [OSTI]

    Oda, Ichiro

    2015-01-01T23:59:59.000Z

    We study black hole radiation of a Reissner-Nordstrom black hole with an electric charge in the framework of quantum gravity. Based on a canonical quantization for a spherically symmetric geometry, under physically plausible assumptions, we solve the Wheeler-De Witt equation in the regions not only between the outer apparent horizon and the spatial infinity but also between the spacetime singularity and the inner apparent horizon, and then show that the mass loss rate of an evaporating black hole due to thermal radiation agrees with the semiclassical result when we choose an integration constant properly by physical reasoning. Furthermore, we also solve the Wheeler-De Witt equation in the region between the inner Cauchy horizon and the outer apparent horizon, and show that the mass loss rate of an evaporating black hole has the same expression. The present study is the natural generalization of the case of a Schwarzschild black hole to that of a charged Reissner-Nordstrom black hole.

  5. Nearly extremal apparent horizons in simulations of merging black holes

    E-Print Network [OSTI]

    Geoffrey Lovelace; Mark A. Scheel; Robert Owen; Matthew Giesler; Reza Katebi; Bela Szilagyi; Tony Chu; Nicholas Demos; Daniel A. Hemberger; Lawrence E. Kidder; Harald P. Pfeiffer; Nousha Afshari

    2014-11-26T23:59:59.000Z

    The spin angular momentum $S$ of an isolated Kerr black hole is bounded by the surface area $A$ of its apparent horizon: $8\\pi S \\le A$, with equality for extremal black holes. In this paper, we explore the extremality of individual and common apparent horizons for merging, rapidly spinning binary black holes. We consider simulations of merging black holes with equal masses $M$ and initial spin angular momenta aligned with the orbital angular momentum, including new simulations with spin magnitudes up to $S/M^2 = 0.994$. We measure the area and (using approximate Killing vectors) the spin on the individual and common apparent horizons, finding that the inequality $8\\pi S extremality by computing the smallest value that Booth and Fairhurst's extremality parameter can take for any scaling. Using this lower bound, we conclude that the common horizons are at least moderately close to extremal just after they appear. Finally, following Lovelace et al. (2008), we construct quasiequilibrium binary-black-hole initial data with "overspun" marginally trapped surfaces with $8\\pi S > A$ and for which our lower bound on their Booth-Fairhurst extremality exceeds unity. These superextremal surfaces are always surrounded by marginally outer trapped surfaces (i.e., by apparent horizons) with $8\\pi Sextremality lower bound on the enclosing apparent horizon is always less than unity but can exceed the value for an extremal Kerr black hole. (Abstract abbreviated.)

  6. Head black woman in charge: An investigation of how black female athletic directors negotiate their race, gender, and class identities

    E-Print Network [OSTI]

    McDowell, Jacqueline

    2009-05-15T23:59:59.000Z

    Framed as an instrumental case study, the purpose of this investigation was to understand how a select group of women, Black female athletic directors, define and negotiate their race, gender, and class identities. Data was collected via a...

  7. Black Hole Solutions in $R^2$ Gravity

    E-Print Network [OSTI]

    Kehagias, Alex; Lust, Dieter; Riotto, Antonio

    2015-01-01T23:59:59.000Z

    We find static spherically symmetric solutions of scale invariant $R^2$ gravity. The latter has been shown to be equivalent to General Relativity with a positive cosmological constant and a scalar mode. Therefore, one expects that solutions of the $R^2$ theory will be identical to that of Einstein theory. Indeed, we find that the solutions of $R^2$ gravity are in one-to-one correspondence with solutions of General Relativity in the case of non-vanishing Ricci scalar. However, scalar-flat $R=0$ solutions are global minima of the $R^2$ action and they cannot in general be mapped to solutions of the Einstein theory. As we will discuss, the $R=0$ solutions arise in Einstein gravity as solutions in the tensionless, strong coupling limit $M_P\\rightarrow 0$. As a further result, there is no corresponding Birkhoff theorem and the Schwarzschild black hole is by no means unique in this framework. In fact, $R^2$ gravity has a rich structure of vacuum static spherically symmetric solutions partially uncovered here. We al...

  8. MASSIVE BLACK HOLES IN CENTRAL CLUSTER GALAXIES

    SciTech Connect (OSTI)

    Volonteri, Marta [Institut d'Astrophysique de Paris, 98bis Bd. Arago, F-75014 Paris (France); Ciotti, Luca [Dipartimento di Fisica e Astronomia, Universita di Bologna, via Ranzani 1, I-40127 Bologna (Italy)

    2013-05-01T23:59:59.000Z

    We explore how the co-evolution of massive black holes (MBHs) and galaxies is affected by environmental effects, addressing in particular MBHs hosted in the central cluster galaxies (we will refer to these galaxies in general as ''CCGs''). Recently, the sample of MBHs in CCGs with dynamically measured masses has increased, and it has been suggested that these MBH masses (M{sub BH}) deviate from the expected correlations with velocity dispersion ({sigma}) and mass of the bulge (M{sub bulge}) of the host galaxy: MBHs in CCGs appear to be ''overmassive''. This discrepancy is more pronounced when considering the M{sub BH}-{sigma} relation than the M{sub BH}-M{sub bulge} one. We show that this behavior stems from a combination of two natural factors: (1) CCGs experience more mergers involving spheroidal galaxies and their MBHs and (2) such mergers are preferentially gas poor. We use a combination of analytical and semi-analytical models to investigate the MBH-galaxy co-evolution in different environments and find that the combination of these two factors is in accordance with the trends observed in current data sets.

  9. Falling through the black hole horizon

    E-Print Network [OSTI]

    Brustein, Ram

    2015-01-01T23:59:59.000Z

    We consider the fate of a small classical object, a "stick", as it falls through the horizon of a large black hole (BH). Classically, the equivalence principle dictates that the stick is affected by small tidal forces, and Hawking's quantum-mechanical model of BH evaporation makes essentially the same prediction. If, on the other hand, the BH horizon is surrounded by a "firewall", the stick will be consumed as it falls through. We have recently extended Hawking's model by taking into account the quantum fluctuations of the geometry and the classical back-reaction of the emitted particles. Here, we calculate the strain exerted on the falling stick for our model. The strain depends on the near-horizon state of the Hawking pairs. We find that, after the Page time when the state of the pairs deviates significantly from maximal entanglement (as required by unitarity), the induced strain in our semiclassical model is still parametrically small. This is because the number of the disentangled pairs is parametrically ...

  10. Black holes, cuspy atmospheres, and galaxy formation

    E-Print Network [OSTI]

    James Binney

    2004-07-12T23:59:59.000Z

    In cuspy atmospheres, jets driven by supermassive black holes (BHs) offset radiative cooling. The jets fire episodically, but often enough that the cuspy atmosphere does not move very far towards a cooling catastrophe in the intervals of jet inactivity. The ability of energy released on the sub-parsec scale of the BH to balance cooling on scales of several tens of kiloparsecs arises through a combination of the temperature sensitivity of the accretion rate and the way in which the radius of jet disruption varies with ambient density. Accretion of hot gas does not significantly increase BH masses, which are determined by periods of rapid BH growth and star formation when cold gas is briefly abundant at the galactic centre. Hot gas does not accumulate in shallow potential wells. As the Universe ages, deeper wells form, and eventually hot gas accumulates. This gas soon prevents the formation of further stars, since jets powered by the BH prevent it from cooling, and it mops up most cold infalling gas before many stars can form. Thus BHs set the upper limit to the masses of galaxies. The formation of low-mass galaxies is inhibited by a combination of photo-heating and supernova-driven galactic winds. Working in tandem these mechanisms can probably explain the profound difference between the galaxy luminosity function and the mass function of dark halos expected in the cold dark matter cosmology.

  11. Effect of pulping conditions and black liquor composition on Newtonian viscosity of high solids kraft black liquors

    SciTech Connect (OSTI)

    Zaman, A.A.; Fricke, A.L. [Univ. of Florida, Gainesville, FL (United States). Dept. of Chemical Engineering] [Univ. of Florida, Gainesville, FL (United States). Dept. of Chemical Engineering

    1996-02-01T23:59:59.000Z

    The influence of black liquor composition and solids concentrations on the Newtonian viscosity of slash pine black liquors over wide ranges of temperature (up to 140 C) and solids concentrations (between 50% and 83% solids) has been studied. It was found that the zero shear rate viscosity of high solids black liquors depends strongly on the cooking conditions and/or black liquor composition. Not only is high solids viscosity affected by lignin molecular weight and lignin concentration in the liquor but other organic and inorganic constituents of black liquor also make a significant contribution to viscosity. The dependency of zero shear rate viscosity on solids concentrations, and temperature is defined. The Newtonian viscosities vary over a wide range depending on temperature, solids concentrations and solids composition. The results indicate that, at fixed levels of effective alkali and sulfidity, the zero shear rate viscosities can be described as a function of both lignin concentration and lignin molecular weight. The viscosity of black liquor is an increasing function of the organics-to-inorganics ratio and is a decreasing function of the concentration of sodium and chloride ions and pH of the liquor.

  12. No Holds Barred Issue 9

    E-Print Network [OSTI]

    Multiple Contributors

    2013-11-27T23:59:59.000Z

    ("Eroica") 18 LOVER'S REQUIEM by Leah Starsky ("Riptide") 38 Art by Sebastion Shaw 41 Art by Cat 42-45 "BlackNight" by Cat ("Wizards and Warriors") 45 MY OWN PRIVATE... FANTASY by Seamus Cody ("My Own Private Idaho") . 46 THENIGHTOF JUST, WELL, RAPINE...

  13. Provenance and diagenesis of the Ivishak Sandstone, northern Alaska

    E-Print Network [OSTI]

    Burch, Gary Kenneth

    1984-01-01T23:59:59.000Z

    . The major detrital species it contains include: a) quartz (49X), dominantly reworked sedimentary and volcanic monocrystalline quartz and metamorphic polycrystalline quartz; b) chert (18/), contain- ing variable amounts of inclusions (clay and carbonate...- stone, Black Warrior basin and the Ouachitas: Q repre- sents monocrystalline quartz, polycrystalline quartz and chert; F represents total feldspar; L represents total lithic fragments. . . . . . . . . . . . . . . . . . . . ~ 52 19 Triangular Q FL...

  14. Thermodynamics of Black Hole Horizons and Kerr/CFT Correspondence

    E-Print Network [OSTI]

    Bin Chen; Shen-xiu Liu; Jia-ju Zhang

    2012-11-02T23:59:59.000Z

    In this paper we investigate the thermodynamics of the inner horizon and its implication on the holographic description of the black hole. We focus on the black holes with two physical horizons. Under reasonable assumption, we prove that the first law of thermodynamics of the outer horizon always indicates that of the inner horizon. As a result, the fact that the area product being mass-independent is equivalent to the relation $T_+S_+=T_-S_-$, with $T_\\pm$ and $S_\\pm$ being the Hawking temperatures and the entropies of the outer and inner horizon respectively. We find that the mass-independence of area product breaks down in general Myers-Perry black holes with spacetime dimension $d\\geq6$ and Kerr-AdS black holes with $d\\geq4$. Moreover we discuss the implication of the first laws of the outer and inner horizons on the thermodynamics of the right- and left-moving sectors of dual CFT in Kerr/CFT correspondence. We show that once the relation $T_+S_+=T_-S_-$ is satisfied, the central charges of two sectors must be same. Furthermore from the thermodynamics relations, we read the dimensionless temperatures of microscopic CFT, which are in exact agreement with the ones obtained from hidden conformal symmetry in the low frequency scattering off the black holes, and then determine the central charges. This method works well in well-known cases in Kerr/CFT correspondence, and reproduce successfully the holographic pictures for 4D Kerr-Newman and 5D Kerr black holes. We go on to predict the central charges and temperatures of a possible holographic CFT description dual to 5D doubly rotating black ring.

  15. Discovering the QCD Axion with Black Holes and Gravitational Waves

    E-Print Network [OSTI]

    Asimina Arvanitaki; Masha Baryakhtar; Xinlu Huang

    2014-12-15T23:59:59.000Z

    Advanced LIGO will be the first experiment to detect gravitational waves. Through superradiance of stellar black holes, it may also be the first experiment to discover the QCD axion with decay constant above the GUT scale. When an axion's Compton wavelength is comparable to the size of a black hole, the axion binds to the black hole, forming a "gravitational atom." Through the superradiance process, the number of axions occupying the bound levels grows exponentially, extracting energy and angular momentum from the black hole. Axions transitioning between levels of the gravitational atom and axions annihilating to gravitons produce observable gravitational wave signals. The signals are long-lasting, monochromatic, and can be distinguished from ordinary astrophysical sources. We estimate up to O(1) transition events at aLIGO for an axion between 10^-11 and 10^-10 eV and up to 10^4 annihilation events for an axion between 10^-13 and 10^-11 eV. In the event of a null search, aLIGO can constrain the axion mass as a function of the formation rate of rapidly spinning black holes. Axion annihilations are also promising for much lighter masses at future lower-frequency gravitational wave observatories, where we expect as many as $10^5$ events. Our projections for aLIGO are robust against perturbations from the black hole environment and account for our updated exclusion on the QCD axion of 6 * 10^-13 eV < ma < 2 * 10^-11 eV suggested by stellar black hole spin measurements.

  16. Entropy spectrum of the D-dimensional massless topological black hole

    E-Print Network [OSTI]

    A. Lopez-Ortega

    2010-06-28T23:59:59.000Z

    There are exact solutions to Einstein's equations with negative cosmological constant that represent black holes whose event horizons are manifolds of negative curvature, the so-called topological black holes. Among these solutions there is one, the massless topological black hole, whose mass is equal to zero. Hod proposes that in the semiclassical limit the asymptotic quasinormal frequencies determine the entropy spectrum of the black holes. Taking into account this proposal, we calculate the entropy spectrum of the massless topological black hole and we compare with the results on the entropy spectra of other topological black holes.

  17. Nearly extremal apparent horizons in simulations of merging black holes

    E-Print Network [OSTI]

    Geoffrey Lovelace; Mark A. Scheel; Robert Owen; Matthew Giesler; Reza Katebi; Bela Szilagyi; Tony Chu; Nicholas Demos; Daniel A. Hemberger; Lawrence E. Kidder; Harald P. Pfeiffer; Nousha Afshari

    2015-02-27T23:59:59.000Z

    The spin angular momentum $S$ of an isolated Kerr black hole is bounded by the surface area $A$ of its apparent horizon: $8\\pi S \\le A$, with equality for extremal black holes. In this paper, we explore the extremality of individual and common apparent horizons for merging, rapidly spinning binary black holes. We consider simulations of merging black holes with equal masses $M$ and initial spin angular momenta aligned with the orbital angular momentum, including new simulations with spin magnitudes up to $S/M^2 = 0.994$. We measure the area and (using approximate Killing vectors) the spin on the individual and common apparent horizons, finding that the inequality $8\\pi S A$ and for which our lower bound on their Booth-Fairhurst extremality exceeds unity. These superextremal surfaces are always surrounded by marginally outer trapped surfaces (i.e., by apparent horizons) with $8\\pi Sblack hole. (Abstract abbreviated.)

  18. Black holes with gravitational hair in higher dimensions

    SciTech Connect (OSTI)

    Anabalon, Andres [Departamento de Ciencias Facultad de Artes Liberales, Facultad de Ingenieria y Ciencias, Universidad Adolfo Ibanez, Vina Del Mar (Chile); Max-Planck-Institut fuer Gravitationsphysik, Albert-Einstein-Institut, Am Muehlenberg 1 D-14476 Golm (Germany); Canfora, Fabrizio [Centro de Estudios Cientificos (CECS), Casilla 1469 Valdivia (Chile); Giacomini, Alex; Oliva, Julio [Instituto de Ciencias Fisicas y Matematicas, Facultad de Ciencias, Universidad Austral de Chile, Valdivia (Chile)

    2011-10-15T23:59:59.000Z

    A new class of vacuum black holes for the most general gravity theory leading to second order field equations in the metric in even dimensions is presented. These space-times are locally anti-de Sitter in the asymptotic region, and are characterized by a continuous parameter that does not enter in the conserve charges, nor it can be reabsorbed by a coordinate transformation: it is therefore a purely gravitational hair. The black holes are constructed as a warped product of a two-dimensional space-time, which resembles the r-t plane of the Banados-Teitelboim-Zanelli black hole, times a warp factor multiplying the metric of a D-2-dimensional Euclidean base manifold, which is restricted by a scalar equation. It is shown that all the Noether charges vanish. Furthermore, this is consistent with the Euclidean action approach: even though the black hole has a finite temperature, both the entropy and the mass vanish. Interesting examples of base manifolds are given in eight dimensions which are products of Thurston geometries, giving then a nontrivial topology to the black hole horizon. The possibility of introducing a torsional hair for these solutions is also discussed.

  19. The Rotating Dyonic Black Holes Of Kaluza-Klein Theory

    E-Print Network [OSTI]

    Dean Rasheed

    1995-05-06T23:59:59.000Z

    The most general electrically and magnetically charged rotating black hole solutions of 5 dimensional \\KK\\ theory are given in an explicit form. Various classical quantities associated with the black holes are derived. In particular, one finds the very surprising result that the gyromagnetic and gyroelectric ratios can become {\\tenit arbitrarily large}. The thermodynamic quantities of the black holes are calculated and a Smarr-type formula is obtained leading to a generalized first law of black hole thermodynamics. The properties of the extreme solutions are investigated and it is shown how they naturally separate into two classes. The extreme solutions in one class are found to have two unusual properties: (i). Their event horizons have zero angular velocity and yet they have non-zero ADM angular momentum. (ii). In certain circumstances it is possible to add angular momentum to these extreme solutions without changing the mass or charges and yet still maintain an extreme solution. Regarding the extreme black holes as elementary particles, their stability is discussed and it is found that they are stable provided they have sufficient angular momentum.

  20. Higher harmonics increase LISA's mass reach for supermassive black holes

    E-Print Network [OSTI]

    K. G. Arun; Bala R. Iyer; B. S. Sathyaprakash; Siddhartha Sinha

    2007-06-05T23:59:59.000Z

    Current expectations on the signal to noise ratios and masses of supermassive black holes which the Laser Interferometer Space Antenna (LISA) can observe are based on using in matched filtering only the dominant harmonic of the inspiral waveform at twice the orbital frequency. Other harmonics will affect the signal-to-noise ratio of systems currently believed to be observable by LISA. More significantly, inclusion of other harmonics in our matched filters would mean that more massive systems that were previously thought to be {\\it not} visible in LISA should be detectable with reasonable SNRs. Our estimates show that we should be able to significantly increase the mass reach of LISA and observe the more commonly occurring supermassive black holes of masses $\\sim 10^8M_\\odot.$ More specifically, with the inclusion of all known harmonics LISA will be able to observe even supermassive black hole coalescences with total mass $\\sim 10^8 M_\\odot (10^9M_\\odot)$ (and mass-ratio 0.1) for a low frequency cut-off of $10^{-4}{\\rm Hz}$ $(10^{-5}{\\rm Hz})$ with an SNR up to $\\sim 60$ $(\\sim 30)$ at a distance of 3 Gpc. This is important from the astrophysical viewpoint since observational evidence for the existence of black holes in this mass range is quite strong and binaries containing such supermassive black holes will be inaccessible to LISA if one uses as detection templates only the dominant harmonic.

  1. Recaustization of kraft black liquor via bipolar electrodialysis

    SciTech Connect (OSTI)

    Koumoundouros, J.A.; Oshen, S.; Lynch, J.D.

    1990-05-01T23:59:59.000Z

    The US Department of Energy in conjunction with HPD Inc. supported a research program to perform a laboratory feasibility study with various black liquor samples for the recaustization of these samples via bipolar electrodialysis. The research was conducted at the HPD pilot plant facility in Plainfield, Illinois, beginning in April 1989. This report is a summary of the work completed thru November 1989. The program was designed to operate the electrodialyzer in order to obtain performance and engineering data such as current efficiency, power consumption per gram of NaOH produced, and assess fouling and/or membrane durability. Prior to the electrodialysis laboratory runs, the black liquor samples were pretreated in order to remove as much lignin as possible. The black liquor samples were air oxidized, acidified to pH = 9.0 and pH = 2.0 and later filtered via a Buchner funnel under vacuum. The filtrate was then utilized to become the feed to the electrodialysis stack. Initial test runs were performed with synthetic solutions of either sodium sulfate or sodium bicarbonate in order to determine acceptable operating current, power, current efficiencies, and fouling behavior. A second set of test were conducted with a series of four Southern Kraft black liquor samples. Based on the results of this study, it was determined that the use of bipolar electrodialysis for producing a caustic stream and an acidified black liquor stream is feasible and was demonstrated. 9 refs., 27 figs., 32 tabs.

  2. Controlled black liquor viscosity reduction through salting-in

    SciTech Connect (OSTI)

    Roberts, J.E.; Khan, S.A.; Spontak, R.J. [North Carolina State Univ., Raleigh, NC (United States)] [North Carolina State Univ., Raleigh, NC (United States)

    1996-08-01T23:59:59.000Z

    Black liquor viscosity increases exponentially with solids content and therefore causes processing problems for the paper industry by being a limiting factor in the Kraft pulp process. This study investigates a new approach for achieving viscosity reduction by salting-in black liquor through the addition of thiocyanate salts. These salts generally increase the solubility of the polymer constituents in black liquor, leading to a decrease in its viscosity. Several thiocyanate salts capable of reducing liquor viscosity by more than two orders of magnitude have been identified, with viscosity reduction greatest at high solids content. Salting-in of black liquor depends on the cation paired with the thiocyanate anion, as well as on solution pH and temperature. Comparative studies reveal the most effective viscosity-reducing agent of the series examined and that lignin plays an important role in the viscosity behavior of both unmodified and salted-in black liquor at high solids concentrations. These experimental findings are interpreted in terms of the underlying principles that describe salting-in and how it affects aqueous solution structure.

  3. The Plasma Puddle as a Perturbative Black Hole

    E-Print Network [OSTI]

    Clifford Cheung; Jared Kaplan

    2007-06-07T23:59:59.000Z

    We argue that the weak coupling regime of a large N gauge theory in the Higgs phase contains black hole-like objects. These so-called ``plasma puddles'' are meta-stable lumps of hot plasma lying in locally un-Higgsed regions of space. They decay via O(1/N) thermal radiation and, perhaps surprisingly, absorb all incident matter. We show that an incident particle of energy E striking the plasma puddle will shower into an enormous number of decay products whose multiplicity grows linearly with E, and whose average energy is independent of E. Once these ultra-soft particles reach the interior they are thermalized by the plasma within, and so the object appears ``black.'' We determine some gross properties like the size and temperature of the the plasma puddle in terms of fundamental parameters in the gauge theory. Interestingly, demanding that the plasma puddle emit thermal Hawking radiation implies that the object is black (i.e. absorbs all incident particles), which implies classical stability, which implies satisfaction of the Bekenstein entropy bound. Because of the AdS/CFT duality and the many similarities between plasma puddles and black holes, we conjecture that black objects are a robust feature of quantum gravity.

  4. Massive Black Hole Science with eLISA

    E-Print Network [OSTI]

    Enrico Barausse; Jillian Bellovary; Emanuele Berti; Kelly Holley-Bockelmann; Brian Farris; Bangalore Sathyaprakash; Alberto Sesana

    2015-01-09T23:59:59.000Z

    The evolving Laser Interferometer Space Antenna (eLISA) will revolutionize our understanding of the formation and evolution of massive black holes along cosmic history by probing massive black hole binaries in the $10^3-10^7$ solar mass range out to redshift $z\\gtrsim 10$. High signal-to-noise ratio detections of $\\sim 10-100$ binary coalescences per year will allow accurate measurements of the parameters of individual binaries (such as their masses, spins and luminosity distance), and a deep understanding of the underlying cosmic massive black hole parent population. This wealth of unprecedented information can lead to breakthroughs in many areas of physics, including astrophysics, cosmology and fundamental physics. We review the current status of the field, recent progress and future challenges.

  5. Thermodynamics of de Sitter Black Holes: Thermal Cosmological Constant

    E-Print Network [OSTI]

    Yuichi Sekiwa

    2006-04-10T23:59:59.000Z

    We study the thermodynamic properties associated with the black hole event horizon and the cosmological horizon for black hole solutions in asymptotically de Sitter spacetimes. We examine thermodynamics of these horizons on the basis of the conserved charges according to Teitelboim's method. In particular, we have succeeded in deriving the generalized Smarr formula among thermodynamical quantities in a simple and natural way. We then show that cosmological constant must decrease when one takes into account the quantum effect. These observations have been obtained if and only if cosmological constant plays the role of a thermodynamical state variable. We also touch upon the relation between inflation of our universe and a phase transition of black holes.

  6. Hoffmann-Infeld Black Hole Solutions in Lovelock Gravity

    E-Print Network [OSTI]

    Matias Aiello; Rafael Ferraro; Gaston Giribet

    2005-05-19T23:59:59.000Z

    Five-dimensional black holes are studied in Lovelock gravity coupled to Hoffmann-Infeld non-linear electrodynamics. It is shown that some of these solutions present a double peak behavior of the temperature as a function of the horizon radius. This feature implies that the evaporation process, though drastic for a period, leads to an eternal black hole remnant. Moreover, the form of the caloric curve corresponds to the existence of a plateau in the evaporation rate, which implies that black holes of intermediate scales turn out to be unstable. The geometrical aspects, such as the absence of conical singularity, the structure of horizons, etc. are also discussed. In particular, solutions that are asymptotically AdS arise for special choices of the parameters, corresponding to charged solutions of five-dimensional Chern-Simons gravity.

  7. Wilson lines for AdS_5 black strings

    E-Print Network [OSTI]

    Kiril Hristov; Stefanos Katmadas

    2014-12-03T23:59:59.000Z

    We describe a simple method of extending AdS_5 black string solutions of 5d gauged supergravity in a supersymmetric way by addition of Wilson lines along a circular direction in space. When this direction is chosen along the string, and due to the specific form of 5d supergravity that features Chern-Simons terms, the existence of magnetic charges automatically generates conserved electric charges in a 5d analogue of the Witten effect. Therefore we find a rather generic, model-independent way of adding electric charges to already existing solutions with no backreaction from the geometry or breaking of any symmetry. We use this method to explicitly write down more general versions of the Benini-Bobev black strings and comment on the implications for the dual field theory and the similarities with generalizations of the Cacciatori-Klemm black holes in AdS_4.

  8. Simulations of binary black hole mergers using spectral methods

    SciTech Connect (OSTI)

    Szilagyi, Bela; Lindblom, Lee; Scheel, Mark A. [Theoretical Astrophysics 350-17, California Institute of Technology, Pasadena, California 91125 (United States)

    2009-12-15T23:59:59.000Z

    Several improvements in numerical methods and gauge choice are presented that make it possible now to perform simulations of the merger and ringdown phases of 'generic' binary black hole evolutions using the pseudospectral evolution code SpEC. These improvements include the use of a new damped-wave gauge condition, a new grid structure with appropriate filtering that improves stability, and better adaptivity in conforming the grid structures to the shapes and sizes of the black holes. Simulations illustrating the success of these new methods are presented for a variety of binary black hole systems. These include fairly generic systems with unequal masses (up to 2 ratio 1 mass ratios), and spins (with magnitudes up to 0.4M{sup 2}) pointing in various directions.

  9. Regular Black Hole Metric with Three Constants of Motion

    E-Print Network [OSTI]

    Johannsen, Tim

    2015-01-01T23:59:59.000Z

    According to the no-hair theorem, astrophysical black holes are uniquely characterized by their masses and spins and are described by the Kerr metric. Several parametric spacetimes which deviate from the Kerr metric have been proposed in order to test this theorem with observations of black holes in both the electromagnetic and gravitational-wave spectra. Such metrics often contain naked singularities or closed timelike curves in the vicinity of the compact objects that can limit the applicability of the metrics to compact objects that do not spin rapidly, and generally admit only two constants of motion. The existence of a third constant, however, can facilitate the calculation of observables, because the equations of motion can be written in first-order form. In this paper, I design a Kerr-like black hole metric which is regular everywhere outside of the event horizon, possesses three independent constants of motion, and depends nonlinearly on four free functions that parameterize potential deviations from ...

  10. Modeling feedback from stars and black holes in galaxy mergers

    E-Print Network [OSTI]

    Springel, V; Hernquist, L; Springel, Volker; Matteo, Tiziana Di; Hernquist, Lars

    2004-01-01T23:59:59.000Z

    We describe techniques for incorporating feedback from star formation and black hole accretion into simulations of isolated and merging galaxies. At present, the details of these processes cannot be resolved in simulations on galactic scales. Our basic approach therefore involves forming coarse-grained representations of the properties of the interstellar medium and black hole accretion starting from basic physical assumptions, so that the impact of these effects can be included on resolved scales. We illustrate our method using a multiphase description of star-forming gas. Feedback from star formation pressurises highly overdense gas, altering its effective equation of state. We show that this allows the construction of stable galaxy models with much larger gas fractions than possible in earlier numerical work. We extend the model by including a treatment of gas accretion onto central supermassive black holes in galaxies. Assuming thermal coupling of a small fraction of the bolometric luminosity of accreting...

  11. "Kerrr" black hole: the Lord of the String

    E-Print Network [OSTI]

    Smailagic, Anais

    2010-01-01T23:59:59.000Z

    Kerrr in the title is not a typo. The third "r" stands for "regular", in the sense of pathology-free, rotating black hole. We exhibit a long search-for, exact, Kerr-like, solution of the Einstein equations with novel features: i) no curvature ring singularity; ii) no "anti-gravity" universe with causality violating timelike closed world-lines; iii) no "super-luminal" matter disk. The ring singularity is replaced by a classical, circular, rotating string with Planck tension representing the inner engine driving the rotation of all the surrounding matter. The resulting geometry is regular and smoothly interpolates among inner Minkowski space, borderline deSitter and outer Kerr universe. The key ingredient to cure all unphysical features of the ordinary Kerr black hole is the choice of a "noncommutative geometry inspired" matter source as the input for the Einstein equations, in analogy with spherically symmetric black holes described in earlier works.

  12. Holographic superconductors with Horava-Lifshitz black holes

    SciTech Connect (OSTI)

    Cai Ronggen; Zhang Haiqing [Key Laboratory of Frontiers in Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, P.O. Box 2735, Beijing 100190 (China)

    2010-03-15T23:59:59.000Z

    We discuss the phase transition of planar black holes in Horava-Lifshitz gravity by introducing a Maxwell field and a complex scalar field. We calculate the condensate of the charged operators in the dual conformal field theories when the mass square of the complex scalar field is m{sup 2}=-2/L{sup 2} and m{sup 2}=0, respectively. We compute the electrical conductivity of the Horava-Lifshitz superconductor in the probe approximation. In particular, it is found that there exists a spike in the conductivity for the case of the operator with scaling dimension one. These results are quite similar to those in the case of Schwarzschild-AdS black holes, which demonstrates that the holographic superconductivity is a robust phenomenon associated with asymptotic AdS black holes.

  13. Classical stability of black holes under massless Dirac perturbations

    E-Print Network [OSTI]

    A. Lopez-Ortega

    2012-11-08T23:59:59.000Z

    In a D-dimensional maximally symmetric spacetime we simplify the massless Dirac equation to two decoupled wavelike equations with effective potentials. Furthermore in D-dimensional Schwarzschild and Schwarzschild de Sitter black holes we note that for the massless Dirac field moving in the region exterior to the event horizon at least one of the effective potentials is not positive definite. Therefore the classical stability of these black holes against this field is not guaranteed. Here with the help of the S-deformation method, we state their classical stability against the massless Dirac field, extend these results to maximally symmetric black holes, and comment on the applicability of our results to establish the stability with respect to other classical fields.

  14. 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

    2008-06-02T23:59:59.000Z

    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.

  15. On Black Hole Masses and Radio Loudness in AGN

    E-Print Network [OSTI]

    Ari Laor

    2000-09-13T23:59:59.000Z

    The distribution of radio to optical fluxes in AGN is bimodal. The physical origin for this bimodality is not understood. In this Letter I describe observational evidence, based on the Boroson & Green PG quasar sample, that the radio loudness bimodality is strongly related to the black hole mass (M_BH). Nearly all PG quasars with M_BH>10^9M_sun are radio loud, while quasars with M_BH<3x10^8M_sun are practically all radio quiet. This result is consistent with the dependence of quasar host galaxy morphology on radio loudness. There is no simple physical explanation for this result, but it may provide a clue on how jets are formed near massive black holes. The radio loudness--black hole mass relationship suggests that the properties of various types of AGN may be largely set by three basic parameters, M_BH, L/L_Eddington, and inclination angle.

  16. Cloud of strings for radiating black holes in Lovelock gravity

    E-Print Network [OSTI]

    Sushant G. Ghosh; Sunil D. Maharaj

    2014-09-28T23:59:59.000Z

    We present exact spherically symmetric null dust solutions in the third order Lovelock gravity with a string cloud background in arbitrary $N$ dimensions,. This represents radiating black holes and generalizes the well known Vaidya solution to Lovelock gravity with a string cloud in the background. We also discuss the energy conditions and horizon structures, and explicitly bring out the effect of the string clouds on the horizon structure of black hole solutions for the higher dimensional general relativity and Einstein-Gauss-Bonnet theories. It turns out that the presence of the coupling constant of the Gauss-Bonnet terms and/or background string clouds completely changes the structure of the horizon and this may lead to a naked singularity. We recover known spherically symmetric radiating models as well as static black holes in the appropriate limits.

  17. Holographic Superconductors with Ho?ava-Lifshitz Black Holes

    E-Print Network [OSTI]

    Rong-Gen Cai; Hai-Qing Zhang

    2009-12-03T23:59:59.000Z

    We discuss the phase transition of planar black holes in Ho\\v{r}ava-Lifshitz gravity by introducing a Maxwell field and a complex scalar field. We calculate the condensates of the charged operators in the dual CFTs when the mass square of the complex scalar filed is $m^2=-2/L^2$ and $m^2=0$, respectively. We compute the electrical conductivity of the \\hl superconductor in the probe approximation. In particular, it is found that there exists a spike in the conductivity for the case of the operator with scaling dimension one. These results are quite similar to those in the case of Schwarzschild-AdS black holes, which demonstrates that the holographic superconductivity is a robust phenomenon associated with asymptotic AdS black holes.

  18. Supercurrent: Vector Hair for an AdS Black Hole

    E-Print Network [OSTI]

    Pallab Basu; Anindya Mukherjee; Hsien-Hang Shieh

    2008-09-26T23:59:59.000Z

    In arXiv:0803.3295 [hep-th] a holographic black hole solution is discussed which exhibits a superconductor like transition. In the superconducting phase the black holes show infinite DC conductivity. This gives rise to the possibility of deforming the solutions by turning on a time independent current (supercurrent), without any electric field. This type of deformation does not exist for normal (non-superconducting) black holes, due to the no-hair theorems. In this paper we have studied such a supercurrent solution and the associated phase diagram. Interestingly, we have found a "special point" (critical point) in the phase diagram where the second order superconducting phase transition becomes first order. Supercurrent in superconducting materials is a well studied phenomenon in condensed matter systems. We have found some qualitative agreement with known results.

  19. Black hole feedback in the luminous quasar PDS 456

    E-Print Network [OSTI]

    Nardini, E; Gofford, J; Harrison, F A; Risaliti, G; Braito, V; Costa, M T; Matzeu, G A; Walton, D J; Behar, E; Boggs, S E; Christensen, F E; Craig, W W; Hailey, C J; Matt, G; Miller, J M; O'Brien, P T; Stern, D; Turner, T J; Ward, M J

    2015-01-01T23:59:59.000Z

    The evolution of galaxies is connected to the growth of supermassive black holes in their centers. During the quasar phase, a huge luminosity is released as matter falls onto the black hole, and radiation-driven winds can transfer most of this energy back to the host galaxy. Over five different epochs, we detected the signatures of a nearly spherical stream of highly ionized gas in the broadband X-ray spectra of the luminous quasar PDS 456. This persistent wind is expelled at relativistic speeds from the inner accretion disk, and its wide aperture suggests an effective coupling with the ambient gas. The outflow's kinetic power larger than 10^46 ergs per second is enough to provide the feedback required by models of black hole and host galaxy co-evolution.

  20. Superconducting instabilities of R-charged black branes

    E-Print Network [OSTI]

    Simon A. Gentle; Benjamin Withers

    2012-07-12T23:59:59.000Z

    We explore superconducting instabilities of black branes in SO(6) gauged supergravity at finite temperature and finite R-charge densities. We compute the critical temperatures for homogeneous neutral and superconducting instabilities in a truncation of 20 scalars and 15 gauge fields as a function of the chemical potentials conjugate to the three U(1) charges in SO(6). We find that despite the imbalance provided by multiple chemical potentials there is always at least one superconducting black brane branch, emerging at a temperature where the normal phase is locally thermodynamically stable. We emphasise that the three-equal charge solution, Reissner-Nordstrom, is subdominant to a thermodynamically unstable black brane at sufficiently low temperatures --- a feature which is hidden in an equal charge truncation.

  1. The Mixed Phase of Charged AdS Black holes

    E-Print Network [OSTI]

    Piyabut Burikham; Chatchai Promsiri

    2015-01-20T23:59:59.000Z

    We study the mixed phase of charged AdS black hole and radiation when the total energy is fixed below the threshold to produce a stable charged black hole branch. The coexistence conditions for the charged AdS black hole and radiation are derived for the generic case when radiation particles carry charge. The phase diagram of the mixed phase is demonstrated for both fixed potential and charge ensemble. In the dual gauge picture, they correspond to the mixed phase of quark-gluon plasma~(QGP) and hadron gas in the fixed chemical potential and density ensemble respectively. In the nuclei and heavy ion collisions at intermediate energies, the mixed phase of exotic QGP and hadron gas could be produced. The mixed phase will condensate and evaporate into the hadron gas as the fireball expands.

  2. Quantum hair and the string-black hole correspondence

    E-Print Network [OSTI]

    Gabriele Veneziano

    2013-03-28T23:59:59.000Z

    We consider a thought experiment in which an energetic massless string probes a "stringhole" (a heavy string lying on the correspondence curve between strings and black holes) at large enough impact parameter for the regime to be under theoretical control. The corresponding, explicitly unitary, $S$-matrix turns out to be perturbatively sensitive to the microstate of the stringhole: in particular, at leading order in $l_s/b$, it depends on a projection of the stringhole's Lorentz-contracted quadrupole moment. The string-black hole correspondence is therefore violated if one assumes quantum hair to be exponentially suppressed as a function of black-hole entropy. Implications for the information paradox are briefly discussed.

  3. Measurement of black liquor surface tension: Technical report No. 3. [Black liquor

    SciTech Connect (OSTI)

    Krishnagopalan, J.

    1987-09-01T23:59:59.000Z

    Surface tension and density of two kraft black liquors were measured at a series of temperatures, from a minimum value when gas bubbles can be blown into the liquor to a maximum value near the elevated boiling point of a particular sample. Available methods for the measurement of surface tension were evaluated critically and, as a result, the maximum bubble pressure method was selected. Varying the flow rate of the gas changes the frequency of bubble formation and thereby the age of the surface. The parameter has been utilized by many researchers to monitor the diffusion of low surface energy components (e.g., surfactants) to the liquid/air interface. The effect of bubble frequency when tested with a few pure liquids, indicated that the dynamics of bubble formation had to be further examined to separate out inertial and viscous effects from purely surface tension related pressure. The pressure versus flow rate data were extrapolated to zero flow rate and surface tension and density were calculated using these extrapolated values. As expected, surface tension decreased with increasing temperature for all the samples. Surface tension decreases with increasing solids content (when compared with the value for water) to a certain level (about 20%) and it starts to increase again. The decrease in surface tension in the dilute black liquor, is probably due to the decrease in the concentration of water, which has a high surface tension value. The occurrence of the minimum is probably due to the effect of inorganic components dominating over the effect of surfactants and other components. Reduction in the solubilities of the inorganics, promotion of micelles of the surfactants and reduction in the diffusion of surfactants to the surface, also could contribute to this phenomenon. 54 refs., 54 figs., 12 tabs.

  4. Charged black holes in expanding Einstein-de Sitter universes

    E-Print Network [OSTI]

    Manuela G. Rodrigues; Vilson T. Zanchin

    2015-02-02T23:59:59.000Z

    Inspired in a previous work by McClure and Dyer (Classical Quantum Gravity 23, 1971 (2006)), we analyze some solutions of the Einstein-Maxwell equations which were originally written to describe charged black holes in cosmological backgrounds. A detailed analysis of the electromagnetic sources for a sufficiently general metric is performed, and then we focus on deriving the electromagnetic four-current as well as the conserved electric charge of each metric. The charged McVittie solution is revisited and a brief study of its causal structure is performed, showing that it may represent a charged black hole in an expanding universe, with the black hole horizon being formed at infinite late times. Charged versions of solutions originally put forward by Vaidya (Vd) and Sultana and Dyer (SD) are also analyzed. It is shown that the charged Sultana-Dyer metric requires a global electric current, besides a central (pointlike) electric charge. With the aim of comparing to the charged McVittie metric, new charged solutions of Vd and SD type are considered. In these cases, the original mass and charge parameters are replaced by particular functions of the cosmological time. In the new generalized charged Vaidya metric the black hole horizon never forms, whereas in the new generalized Sultana-Dyer case both the Cauchy and the black hole horizons develop at infinite late times. A charged version of the Thakurta metric is also studied here. It is also a new solution. As in the charged Sultana-Dyer case, the natural source of the electromagnetic field is a central electric charge with an additional global electric current. The global structure is briefly studied and it is verified that the corresponding spacetime may represent a charged black hole in a cosmological background. All the solutions present initial singularities as found in the McVittie metric.

  5. The Impact of City Contracting Set-Asides on Black Self-Employment and Employment

    E-Print Network [OSTI]

    Chatterji, Aaron K; Chay, Kenneth Y; Fairlie, Robert W

    2013-01-01T23:59:59.000Z

    2012. The Impact of City Contracting Set- Asides on BlackAction? Government Contracting and California's PropositionThe Impact of City Contracting Set-Asides on Black Self-

  6. Search for gravitational wave ringdowns from perturbed black holes in LIGO S4 data

    E-Print Network [OSTI]

    Zucker, Michael E.

    According to general relativity a perturbed black hole will settle to a stationary configuration by the emission of gravitational radiation. Such a perturbation will occur, for example, in the coalescence of a black hole ...

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

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

    and in the built-in media storage on the BlackBerry smartphone, but not email and other personal information stored on the file system of the BlackBerry smartphone. The following...

  8. Isolated Horizons: A Generalization of Black Hole Mechanics

    E-Print Network [OSTI]

    Abhay Ashtekar; Christopher Beetle; Stephen Fairhurst

    1998-12-18T23:59:59.000Z

    A set of boundary conditions defining a non-rotating isolated horizon are given in Einstein-Maxwell theory. A space-time representing a black hole which itself is in equilibrium but whose exterior contains radiation admits such a horizon . Physically motivated, (quasi-)local definitions of the mass and surface gravity of an isolated horizon are introduced. Although these definitions do not refer to infinity, the quantities assume their standard values in Reissner-Nordstrom solutions. Finally, using these definitions, the zeroth and first laws of black hole mechanics are established for isolated horizons.

  9. A classical instability for black strings and p-branes

    SciTech Connect (OSTI)

    Gregory, R. (Chicago Univ., IL (United States). Enrico Fermi Inst.); Laflamme, R. (Los Alamos National Lab., NM (United States))

    1993-01-01T23:59:59.000Z

    We investigate the evolution of small perturbations around black of strings and branes which are low energy solutions of string theory. For simplicity we focus attention on the zero charge case and show that there are unstable modes for a range of time frequency and wavelength in the extra 10 - D dimensions. These perturbations can be stabilized if the extra dimensions are compactified to a scale smaller than the minimum wavelength for which instability occurs and thus will not affect large astrophysical black holes in four dimensions. We comment on the implications of this result for the Cosmic Censorship Hypothesis

  10. A classical instability for black strings and p-branes

    SciTech Connect (OSTI)

    Gregory, R. [Chicago Univ., IL (United States). Enrico Fermi Inst.; Laflamme, R. [Los Alamos National Lab., NM (United States)

    1993-06-01T23:59:59.000Z

    We investigate the evolution of small perturbations around black of strings and branes which are low energy solutions of string theory. For simplicity we focus attention on the zero charge case and show that there are unstable modes for a range of time frequency and wavelength in the extra 10 - D dimensions. These perturbations can be stabilized if the extra dimensions are compactified to a scale smaller than the minimum wavelength for which instability occurs and thus will not affect large astrophysical black holes in four dimensions. We comment on the implications of this result for the Cosmic Censorship Hypothesis

  11. Exploring higher dimensional black holes at the large hadron collider.

    E-Print Network [OSTI]

    Harris, Chris M; Palmer, M J; Parker, Michael A; Richardson, P

    of extra dimensions. Throughout, we have used the ATLAS fast simulation software [20] to give a description of a typical detector and we have used the full simulation [21] to verify the main results. 2. Black hole production and decay In the black hole... evolution from present energies is questionable. Also, comparison to Standard Model pro- cesses in the trans-Planckian regime would be difficult since perturbative physics would be suppressed. 4.2 The first stages of decay CHARYBDIS does not model...

  12. Thermodynamics of Schrdinger black holes with hyperscaling violation

    E-Print Network [OSTI]

    J. Sadeghi; B. Pourhassan; F. Pourasadollah

    2012-11-06T23:59:59.000Z

    In this work, we follow Kim and Yamada (JHEP1107 (2011) 120) and utilize AdS in light-cone frame to derive thermodynamic and transport properties of two kinds of Schr\\"{o}dinger black holes with hyperscaling violation. In that case, we show entropy and temperature are depend on $\\theta$. In $\\theta=0$ we see our results are agree with the work of Kim and Yamada. We also construct R-charged black hole with hyperscaling violation and obtain thermodynamics and transport properties.

  13. Dirac monopoles on Kerr black holes: comparing gauges

    E-Print Network [OSTI]

    Yu. P. Goncharov

    1998-11-17T23:59:59.000Z

    We update our previous work on the description of twisted configurations for complex massless scalar field on the Kerr black holes as the sections of complex line bundles over the Kerr black hole topology. From physical point of view the appearance of twisted configurations is linked with the natural presence of Dirac monopoles that arise as connections in the above line bundles. We consider their description in the gauge inequivalent to the one studied previously and discuss a row of new features appearing in this gauge.

  14. Over-spinning a black hole with a test body

    E-Print Network [OSTI]

    Ted Jacobson; Thomas P. Sotiriou

    2009-12-01T23:59:59.000Z

    It has long been known that a maximally spinning black hole can not be over-spun by tossing in a test body. Here we show that if instead the black hole starts out with below maximal spin, then indeed over-spinning can be achieved when adding either orbital or spin angular momentum. We find that requirements on the size and internal structure of the test body can be met as well. Our analysis neglects radiative and self-force effects,which may prevent the over-spinning.

  15. Semiclassical Decay of Near-Extremal Black Holes

    E-Print Network [OSTI]

    Ted Jacobson

    1998-03-26T23:59:59.000Z

    Decay of a near-extremal black hole down to the extremal state is studied in the background field approximation to determine the fate of injected matter and Hawking pairs. By examining the behavior of light rays and solutions to the wave equation it is concluded that the singularity at the origin is irrelevant. Furthermore, there is most likely an instability of the event horizon arising from the accumulation of injected matter and Hawking partners there. The possible role of this instability in reconciling the D-brane and black hole pictures of the decay process is discussed.

  16. Black hole entanglement entropy and the renormalization group

    E-Print Network [OSTI]

    Ted Jacobson; Alejandro Satz

    2013-03-21T23:59:59.000Z

    We investigate the contributions of quantum fields to black hole entropy by using a cutoff scale at which the theory is described with a Wilsonian effective action. For both free and interacting fields, the total black hole entropy can be partitioned into a contribution derived from the gravitational effective action and a contribution from quantum fluctuations below the cutoff scale. In general the latter includes a quantum contribution to the Noether charge. We analyze whether it is appropriate to identify the rest with horizon entanglement entropy, and find several complications for this interpretation, which are especially problematic for interacting fields.

  17. Particle Radiation From Gibbons-Maeda Black Hole

    E-Print Network [OSTI]

    Heng-Zhong Fang; Jian-Yang Zhu

    2006-11-02T23:59:59.000Z

    This paper investigates the particle radiation from Gibbons-Maeda black hole. Taking into account the self-gravitation of the particle, we calculate the tunnelling rate of the massless particle across the horizon, then we promote the work to the radiation of the charged particle. The calculations prove that the rate of tunnelling equals precisely the exponent of the difference of the black hole entropy before and after emission and the radiation spectrum deviates from exact thermal. The conclusion supports the viewpoint of information conservation.

  18. Black liquor gasification phase 2D final report

    SciTech Connect (OSTI)

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

    1988-06-01T23:59:59.000Z

    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.

  19. Physical properties of Kraft Black Liquor. Interim report, Phase II

    SciTech Connect (OSTI)

    Fricke, A.L.

    1985-03-01T23:59:59.000Z

    Objectives are to determine the rheological, thermal, and surface properties of Kraft Black Liquors, and to relate these properties to the chemical composition and to pulping conditions. A four-variable, multi-level pulping experiment is being conducted. Pulping results are reported. Complete analyses of the liquors have been done. Thermal analyses have been done. DSC was employed to determine heat capacities of black liquors and lignins. Rheological (viscosity) studies are being conducted. Density and thermal expansion have been studied for seven liquors. Energy savings through more efficient recovery systems are appreciable.

  20. Electromagnetic quasinormal modes of D-dimensional black holes II

    E-Print Network [OSTI]

    A. Lpez-Ortega

    2007-06-20T23:59:59.000Z

    By using the sixth order WKB approximation we calculate for an electromagnetic field propagating in D-dimensional Schwarzschild and Schwarzschild de Sitter black holes its quasinormal frequencies for the fundamental mode and first overtones. We study the dependence of these QN frequencies on the value of the cosmological constant and the spacetime dimension. We also compare with the known results for the gravitational perturbations propagating in the same background. Moreover we exactly compute the QN frequencies of the electromagnetic field propagating in D-dimensional massless topological black hole and for charged D-dimensional Nariai spacetime we exactly calculate the QN frequencies of the coupled electromagnetic and gravitational perturbations.

  1. Construction of a Penrose Diagram for an Accreting Black Hole

    E-Print Network [OSTI]

    Beth A. Brown; James Lindesay

    2008-11-04T23:59:59.000Z

    A Penrose diagram is constructed for a spatially coherent black hole that accretes at stepwise steady rates as measured by a distant observer from an initial state described by a metric of Minkowski form. Coordinate lines are computationally derived, and radial light-like trajectories verify the viability of the diagram. Coordinate dependencies of significant features, such as the horizon and radial mass scale, are clearly demonstrated on the diagram. The onset of a singularity at the origin is shown to open a new region in space-time that contains the interior of the black hole.

  2. Stationary black-hole binaries: A non-existence proof

    E-Print Network [OSTI]

    Gernot Neugebauer; Jrg Hennig

    2014-06-23T23:59:59.000Z

    We resume former discussions of the question, whether the spin-spin repulsion and the gravitational attraction of two aligned black holes can balance each other. Based on the solution of a boundary problem for disconnected (Killing) horizons and the resulting violation of characteristic black hole properties, we present a non-existence proof for the equilibrium configuration in question. From a mathematical point of view, this result is a further example for the efficiency of the inverse ("scattering") method in non-linear theories.

  3. Pollen analysis of Anasazi sites at Black Mesa, Arizona

    E-Print Network [OSTI]

    Murry, Robert Earl

    2012-06-07T23:59:59.000Z

    POLLEN ANALYSIS OF ANASAZI SITES AT BLACK MESA, ARIZONA A Thesis by ROBERT EARL MURRY, JR. Submitted to the Graduate College of Texas ASM IJnlversity in partial fulfillment of the requirement for the degree of MASTER OF ARTS August 1983... Major Subject: Anthropology POLLEN ANALYSIS OF ANASAZI SITES AT BLACK MESA, ARIZONA A Thesis by ROBERT EARL MURRY, "Jr. Approved as to style and content by: G en on H. Weir (Chairman of Committee) a . Sha e e er) Hug D. Wilson (Member) Va ghn...

  4. Supermassive Black Holes and the Evolution of Galaxies

    E-Print Network [OSTI]

    D. Richstone; E. A. Ajhar; R. Bender; G. Bower; A. Dressler; S. M. Faber; A. V. Filippenko; K. Gebhardt; R. Green; L. C. Ho; J. Kormendy; T. Lauer; J. Magorrian; S. Tremaine

    1998-10-23T23:59:59.000Z

    Black holes, an extreme consequence of the mathematics of General Relativity, have long been suspected of being the prime movers of quasars, which emit more energy than any other objects in the Universe. Recent evidence indicates that supermassive black holes, which are probably quasar remnants, reside at the centers of most galaxies. As our knowledge of the demographics of these relics of a violent earlier Universe improve, we see tantalizing clues that they participated intimately in the formation of galaxies and have strongly influenced their present-day structure.

  5. Energy Associated with Schwarzschild Black Hole in a Magnetic Universe

    E-Print Network [OSTI]

    S. S. Xulu

    2000-01-29T23:59:59.000Z

    In this paper we obtain the energy distribution associated with the Ernst space-time (geometry describing Schwarzschild black hole in Melvin's magnetic universe) in Einstein's prescription. The first term is the rest-mass energy of the Schwarzschild black hole, the second term is the classical value for the energy of the uniform magnetic field and the remaining terms in the expression are due to the general relativistic effect. The presence of the magnetic field is found to increase the energy of the system.

  6. Black Hole Collisions, Analytic Continuation, and Cosmic Censorship

    E-Print Network [OSTI]

    Dieter R. Brill

    1995-03-27T23:59:59.000Z

    Exact solutions of the Einstein-Maxwell equations that describe moving black holes in a cosmological setting are discussed with the aim of discovering the global structure and testing cosmic censorship. Continuation beyond the horizons present in these solutions is necessary in order to identify the global structure. Therefore the possibilities and methods of analytic extension of geometries are briefly reviewed. The global structure of the Reissner-Nordstr\\"om-de Sitter geometry is found by these methods. When several black holes are present, the exact solution is no longer everywhere analytic, but less smooth extensions satisfying the Einstein equations everywhere are possible. Some of these provide counterexamples to cosmic censorship.

  7. Using the master's tools : representations of blackness and the strategies of stereotype

    E-Print Network [OSTI]

    Zygmonski, Aimee

    2010-01-01T23:59:59.000Z

    Press, 1998. - - -. Optic Black: Naturalizing the Refusal to Fit. Michigan Press, 2001. Carpio, Glenda. Laughing Fit to Kill:

  8. ARTHROPOD BIOLOGY Selected Life-History Traits of Black Soldier Flies

    E-Print Network [OSTI]

    Tomberlin, Jeff

    materials, such as fruits, animals, and ma- nure (James 1935). The black soldier ?y is interesting because

  9. Sensitivity of stratospheric geoengineering with black carbon to aerosol size and altitude of injection

    E-Print Network [OSTI]

    Sensitivity of stratospheric geoengineering with black carbon to aerosol size and altitude geoengineering with black carbon (BC) aerosols using a general circulation model with fixed sea surface involving sulfate aerosols, black carbon geoengineering likely carries too many risks to make it a viable

  10. Red-Black Relaxed Plan Heuristics Michael Katz and Jorg Hoffmann

    E-Print Network [OSTI]

    Domshlak, Carmel

    Red-Black Relaxed Plan Heuristics Michael Katz and J¨org Hoffmann Saarland University Saarbr the red-black planning frame- work, where red variables take the relaxed semantics (accu- mulating their values), while black variables take the regular semantics. Provided the red variables are chosen so

  11. ORIGINAL PAPER The south-western Black Forest and the Upper Rhine Graben

    E-Print Network [OSTI]

    Wetzel, Andreas

    ORIGINAL PAPER The south-western Black Forest and the Upper Rhine Graben Main Border Fault: thermal ? Springer-Verlag 2008 Abstract The thermal history of the south-westernmost Black Forest (Germany) and microstructural analyses. After intrusion of Palaeozoic granitic plutons in the Black Forest, the thermal regime

  12. Dark Energy Accretion onto a Black Hole in an Expanding Universe

    E-Print Network [OSTI]

    Cheng-Yi Sun

    2009-03-14T23:59:59.000Z

    By using the solution describing a black hole embedded in the FLRW universe, we obtain the evolving equation of the black hole mass expressed in terms of the cosmological parameters. The evolving equation indicates that in the phantom dark energy universe the black hole mass becomes zero before the Big Rip is reached.

  13. Entropy bound of a charged object and electrostatic self-energy in black holes

    E-Print Network [OSTI]

    B. Linet

    1999-11-30T23:59:59.000Z

    Without pretending to any rigour, we find a general expression of the electrostatic self-energy in static black holes with spherical symmetry. We determine the entropy bound of a charged object by assuming the existence of thermodynamics for these black holes. By combining these two results, we show that the entropy bound does not depend on the considered black hole.

  14. A study of black aurora from aircraft-based optical observations and plasma measurements on FAST

    E-Print Network [OSTI]

    California at Berkeley, University of

    A study of black aurora from aircraft-based optical observations and plasma measurements on FAST L 2002. [1] Black aurora was observed on 30 January 1998 in a narrow-field camera forty seconds before. Electron energy flux measured by FAST provided strong evidence that FAST passed over black aurora

  15. Holography, Gauge-gravity Connection and Black Hole Entropy Parthasarathi Majumdar,

    E-Print Network [OSTI]

    ;Created with pptalk Slide 2 Black holes : Extreme gravitation at work what lies beyond the `hori- zon' observationally unknown Inaccessibility apprehensions Turn to theory Black Holes from Newton's law ? Dark stars faster than c ? #12;Created with pptalk Slide 2 Black holes : Extreme gravitation at work what lies

  16. Origins and accumulation of organic matter in expanded Albian to Santonian black shale sequences on the

    E-Print Network [OSTI]

    Gilli, Adrian

    Origins and accumulation of organic matter in expanded Albian to Santonian black shale sequences laminated, Cenoma- nian­Santonian black shale sequences contain between 2% and 15% organic carbon about the depositional conditions leading to the black shale accumulations. The low d13 Corg values

  17. Absorption of planar massless scalar waves by Bardeen regular black holes

    E-Print Network [OSTI]

    Caio F. B. Macedo; Lus C. B. Crispino

    2014-09-09T23:59:59.000Z

    Accretion of fields by black holes is a subject of great interest in physics. It is known that accretion plays a fundamental role in active galactic nuclei and in the evolution of black holes. Accretion of fundamental fields is often related to the study of absorption cross section. Basically all black holes for which absorption of fields has been studied so far present singularities. However, even within general relativity, it is possible to construct regular black holes: objects with event horizons but without singularities. Many physically motivated regular black hole solutions have been proposed in the past years, demanding the understanding of their absorption properties. We study the absorption of planar massless scalar waves by Bardeen regular black holes. We compare the absorption cross section of Bardeen and Reissner--Nordstr\\"om black holes, showing that the former always have a bigger absorption cross section for fixed values of the field frequency and of the normalized black hole charge. We also show that it is possible for a Bardeen black hole to have the same high-frequency absorption cross section of a Reissner--Nordstr\\"om black hole. Our results suggest that, in mid-to-high-frequency regimes, regular black holes can have compatible properties with black holes with singularities, as far as absorption is concerned.

  18. Fun With Plasma Turbulence, From Fusion Energy to Black Holes

    E-Print Network [OSTI]

    Hammett, Greg

    ) & in astrophysics · Summarize status of fusion energy research · Cross-validation: statistical techniques useful Energy is Essentially Unchanged since 1980 Cumulative Funding 0 5000 10000 15000 20000 25000 30000 35000Fun With Plasma Turbulence, From Fusion Energy to Black Holes Greg Hammett Miller Visiting Research

  19. Bulk emission of scalars by a rotating black hole

    E-Print Network [OSTI]

    M. Casals; S. R. Dolan; P. Kanti; E. Winstanley

    2008-07-17T23:59:59.000Z

    We study in detail the scalar-field Hawking radiation emitted into the bulk by a higher-dimensional, rotating black hole. We numerically compute the angular eigenvalues, and solve the radial equation of motion in order to find transmission factors. The latter are found to be enhanced by the angular momentum of the black hole, and to exhibit the well-known effect of superradiance. The corresponding power spectra for scalar fields show an enhancement with the number of dimensions, as in the non-rotating case. We compute the total mass loss rate of the black hole for a variety of black-hole angular momenta and bulk dimensions, and find that, in all cases, the bulk emission remains significantly smaller than the brane emission. The angular-momentum loss rate is also computed and found to have a smaller value in the bulk than on the brane. We present accurate bulk-to-brane emission ratios for a range of scenarios.

  20. Properties of Disorder-Engineered Black Titanium Dioxide Nanoparticles through

    E-Print Network [OSTI]

    hydrogen atom could easily bond to a terminal oxygen site13 . The observed hydrogen diffusion into the TiO2Properties of Disorder-Engineered Black Titanium Dioxide Nanoparticles through Hydrogenation Xiaobo, on the other hand, can undergo fast diffusion and exchange. The enhanced hydrogen mobility may be explained

  1. Infrared spectra of carbon monoxide adsorbed on palladium black

    SciTech Connect (OSTI)

    Vozdvizhenskii, V.F.; Levintova, T.D.; Sokol'skii, D.V.

    1986-06-01T23:59:59.000Z

    The authors investigate the heterogeneous adsorption of carbon monoxide and the concurrent catalytic and sorptive properties of palladium black from the standpoint of a comprehensive analysis of the infrared spectra of the reaction pathways and their various products as well as the pressure dependence of the line behavior at various wavelengths.

  2. Gravitational Self-Energy and Black Holes in Newtonian Physics

    E-Print Network [OSTI]

    G. Dillon

    2013-02-15T23:59:59.000Z

    A definition of a Newtonian black hole is possible which incorporates the mass-energy equivalence from special relativity. However, exploiting a double spherical shell model, it will be shown that the ensuing gravitational self-energy and mass renormalization prevent the formation of such an object.

  3. Measuring the Black Hole Spin in Sgr A*

    E-Print Network [OSTI]

    Fulvio Melia; Benjamin C. Bromley; Siming Liu; Christopher; K. Walker

    2001-05-11T23:59:59.000Z

    The polarized mm/sub-mm radiation from Sgr A* is apparently produced by a Keplerian structure whose peak emission occurs within several Schwarzschild radii (r_S=2GM/c^2) of the black hole. The Chandra X-ray counterpart, if confirmed, is presumably the self-Comptonized component from this region. In this paper, we suggest that sub-mm timing observations could yield a signal corresponding to the period P_0 of the marginally stable orbit, and therefore point directly to the black hole's spin a. Sgr A*'s mass is now known to be (2.6\\pm 0.2)\\times 10^6 M_\\odot (an unusually accurate value for supermassive black hole candidates), for which 2.7 minblack hole (a=0) should have P_0 ~ 20 min. The identification of the orbital frequency with the innermost stable circular orbit is made feasible by the transition from optically thick to thin emission at sub-mm wavelengths. With stratification in the emitter, the peak of the sub-mm bump in Sgr A*'s spectrum is thus produced at the smallest radius. We caution, however, that theoretical uncertainties in the structure of the emission region may still produce some ambiguity in the timing signal. Given that Sgr A*'s flux at $\

  4. Report on the WORKSHOP ON COMMERCIALIZATION OF BLACK LIQUOR

    E-Print Network [OSTI]

    Report on the WORKSHOP ON COMMERCIALIZATION OF BLACK LIQUOR AND BIOMASS GASIFICATION FOR GAS or industry cycle (BGCC) technologies for pulp and paper co~mitm~nt to the develo~ment of gasification systems (existing) technology with an greenhouse gas emissions mitigation measures. emerging (gasification

  5. NSF GA-32589X I CHARACTERISTICS OF CARBON BLACK

    E-Print Network [OSTI]

    Gray, William

    for years. The amount of solar energy which can be absorbed by carbon black and transmitted to the air and the reduced solar radiation available inside the cloud. Such problems are to be expected when attempting particles in aerosol form spread artificially in the atmosphere to absorb solar radiation and hence

  6. Increase of Black Hole Entropy in Higher Curvature Gravity

    E-Print Network [OSTI]

    Ted Jacobson; Gungwon Kang; Robert C. Myers

    1995-03-11T23:59:59.000Z

    We examine the Zeroth Law and the Second Law of black hole thermodynamics within the context of effective gravitational actions including higher curvature interactions. We show that entropy can never decrease for quasi-stationary processes in which a black hole accretes positive energy matter, independent of the details of the gravitational action. Within a class of higher curvature theories where the Lagrangian consists of a polynomial in the Ricci scalar, we use a conformally equivalent theory to establish that stationary black hole solutions with a Killing horizon satisfy the Zeroth Law, and that the Second Law holds in general for any dynamical process. We also introduce a new method for establishing the Second Law based on a generalization of the area theorem, which may prove useful for a wider class of Lagrangians. Finally, we show how one can infer the form of the black hole entropy, at least for the Ricci polynomial theories, by integrating the changes of mass and angular momentum in a quasistationary accretion process.

  7. Radiation interference from sources rotating around Schwarzschild black holes

    E-Print Network [OSTI]

    Raissa F. P. Mendes; George E. A. Matsas

    2011-10-04T23:59:59.000Z

    We investigate the influence of the spacetime curvature on the interference of the radiation emitted by an ensemble of scalar sources in circular motion around a Schwarzschild black hole. We pay particular attention to the transition from the radiating to the non-radiating regime as the number of sources increases.

  8. No Scalar Hair Theorem for a Charged Spherical Black Hole

    E-Print Network [OSTI]

    N. Banerjee; S. Sen

    1998-08-11T23:59:59.000Z

    This paper consolidates noscalar hair theorem for a charged spherically symmetric black hole in four dimension in general relativity as well as in all scalar tensor theories, both minimally and nonminimally coupled, when the effective Newtonian constant of gravity is positive. However, there is an exception when the matter field itself is coupled to the scalar field, such as in dilaton gravity.

  9. Ecology of Wintering Black-capped Vireos in Mexico

    E-Print Network [OSTI]

    Powell, Robert Andrew

    2013-11-06T23:59:59.000Z

    . Winter habitat use by black-capped vireos was best predicted by increasing values of slope and foliage cover, and by decreasing values of canopy cover and tree diameter. Vireo use plots characterized as thorn forest had greater foliage density, greater...

  10. Accelerating black holes in anti-de Sitter universe

    E-Print Network [OSTI]

    J. Podolsky

    2002-02-11T23:59:59.000Z

    A physical interpretation of the C-metric with a negative cosmological constant $\\Lambda$ is suggested. Using a convenient coordinate system it is demonstrated that this class of exact solutions of Einstein's equations describes uniformly accelerating (possibly charged) black holes in anti-de Sitter universe. Main differences from the analogous de Sitter case are emphasised.

  11. Conserved Charges and Thermodynamics of the Spinning Goedel Black Hole

    SciTech Connect (OSTI)

    Barnich, Glenn; Compere, Geoffrey [Physique Theorique et Mathematique, Universite Libre de Bruxelles, and International Solvay Institutes, Campus Plaine C.P. 231, B-1050 Brussels (Belgium)

    2005-07-15T23:59:59.000Z

    We compute the mass, angular momenta, and charge of the Goedel-type rotating black hole solution to five-dimensional minimal supergravity. A generalized Smarr formula is derived, and the first law of thermodynamics is verified. The computation rests on a new approach to conserved charges in gauge theories that allows for their computation at finite radius.

  12. Sodium and sulfur release and recapture during black liquor burning

    SciTech Connect (OSTI)

    Frederick, W.J.; Iisa, K.; Wag, K.; Reis, V.V.; Boonsongsup, L.; Forssen, M.; Hupa, M.

    1995-08-01T23:59:59.000Z

    The objective of this study was to provide data on sulfur and sodium volatilization during black liquor burning, and on SO2 capture by solid sodium carbonate and sodium chloride. This data was interpreted and modeled into rate equations suitable for use in computational models for recovery boilers.

  13. Reissner-Nordstrom black hole in dark energy background

    E-Print Network [OSTI]

    Ngangbam Ishwarchandra; Ng. Ibohal; K. Yugindro Singh

    2014-11-29T23:59:59.000Z

    In this paper we propose a stationary solution of Einstein's field equations describing Reissner-Nordstrom black hole in dark energy background. It is to be regarded as the Reissner-Nordstrom black hole is embedded into the dark energy solution producing Reissner-Nordstrom-dark energy black hole. We find that the space-time geometry of Reissner-Nordstrom-dark energy solution is Petrov type $D$ in the classification of space-times. It is also shown that the embedded space-time possesses an energy-momentum tensor of the electromagnetic field interacting with the dark energy having negative pressure. We find the energy-momentum tensor for dark energy violates the the strong energy condition due to the negative pressure, whereas that of the electromagnetic field obeys the strong energy condition. It is shown that the time-like vector field for an observer in the Reissner-Nordstrom-dark energy space is expanding, accelerating, shearing and non-rotating. We investigate the surface gravity of the horizons for the embedded dark energy black hole. The characteristic properties of relativistic dark energy based on the de Sitter solution is discussed in an appendix.

  14. Curing black hole singularities with local scale invariance

    E-Print Network [OSTI]

    Predrag Dominis Prester

    2014-02-27T23:59:59.000Z

    We show that Weyl-invariant dilaton gravity provides a description of black holes without classical spacetime singularities. Singularities appear due to ill-behavior of gauge fixing conditions, one example being the gauge in which theory is classically equivalent to standard General Relativity. The main conclusions of our analysis are: (1) singularities signal a phase transition from broken to unbroken phase of Weyl symmetry, (2) instead of a singularity there is a "baby-universe" inside a black hole, (3) there is a critical mass after which reducing mass makes black hole larger as viewed by outside observers, (4) if a black hole could be connected with white hole through the "singularity", this would require breakdown of (classical) geometric description. The singularity of Schwarzschild BH solution is non-generic and so it it dangerous to rely on it in deriving general results. Our results may have important consequences for resolving issues related to information-loss puzzle. The theory we use is basically a completion of General Relativity, containing neither additional physical excitations nor higher-derivative terms, but requires physical scalar field such as Higgs field of Standard Model. Though quantum effects are still crucial and may change the proposed classical picture, a position of building quantum theory around regular classical solutions (without singularities) normally provides a much better starting point.

  15. Primordial black holes from temporally enhanced curvature perturbation

    E-Print Network [OSTI]

    Teruaki Suyama; Yi-Peng Wu; Jun'ichi Yokoyama

    2014-06-02T23:59:59.000Z

    Scalar field with generalized kinetic interactions metamorphoses depending on its field value, ranging from cosmological constant to stiff matter. We show that such a scalar field can give rise to temporal enhancement of the curvature perturbation in the primordial Universe, leading to efficient production of primordial black holes while the enhancement persists. If the inflation energy scale is high, those mini-black holes evaporate by the Hawking radiation much before Big Bang nucleosynthesis and the effective reheating of the Universe is achieved by the black hole evaporation. Dominance of PBHs and the reheating by their evaporation modify the expansion history of the primordial Universe. This results in a characteristic feature of the spectrum of primordial tensor modes in the DECIGO frequency band, opening an interesting possibility of testing PBH reheating scenario by measuring the primordial tensor modes. If the inflation energy scale is low, the PBH mass can be much larger than the solar mass. In this case, PBH is an interesting candidate for seeds for supermassive black holes residing in present galaxies.

  16. Ultrafiltration of kraft black liquor: Final report, Phase 3

    SciTech Connect (OSTI)

    Hill, M.K.

    1988-04-01T23:59:59.000Z

    Since 1981, a research program has been in progress to determine the physical properties of kraft black liquors and to develop methods for reduction of data and correlation of properties with pumping conditions. The basic premise that has been used to direct the research program is that kraft black liquor behaves as a polymer solution, particularly at high solids, and that the behavior is dominated by the characteristics of the lignin present. This premise is proving to be correct, and the principles that follow from this premise are proving to be successful for data reduction and correlation. The research has been a complex program involving experimental pulping, chemical analysis, lignin separation and characterization, thermal analysis, rheological measurements, and considerable equipment and methods development. Due to the complexity of the program, the unforeseen need to expend a great deal of effort in development of experimental techniques for analysis, and the fact that our liquors proved to be unstable at high temperatures and solids, all of the original objectives could not be accomplished. However, our program has added substantially to the body of knowledge of physical properties of black liquor. Our results indicate that the goal of developing correlations for physical properties of kraft black liquor is practical and can be realized through extension of the present work. 21 refs., 32 figs.

  17. In situ analysis of ash deposits from black liquor combustion

    SciTech Connect (OSTI)

    Bernath, P. [Sandia National Labs., Livermore, CA (United States). Combustion Research Facility]|[Univ. of Toronto, Ontario (Canada); Sinquefield, S.A. [Sandia National Labs., Livermore, CA (United States). Combustion Research Facility]|[Oregon State Univ., Eugene, OR (United States); Baxter, L.L.; Sclippa, G.; Rohlfing, C. [Sandia National Labs., Livermore, CA (United States). Combustion Research Facility; Barfield, M. [Sandia National Labs., Livermore, CA (United States). Combustion Research Facility]|[Univ. of Arizona, Tucson, AZ (United States)

    1996-05-01T23:59:59.000Z

    Aerosols formed during combustion of black liquor cause a significant fire-side fouling problem in pulp mill recovery boilers. The ash deposits reduce heat transfer effectiveness, plug gas passages, and contribute to corrosion. Both vapors and condensation aerosols lead to the formation of such deposits. The high ash content of the fuel and the low dew point of the condensate salts lead to a high aerosol and vapor concentration in most boilers. In situ measurements of the chemical composition of these deposits is an important step in gaining a fundamental understanding of the deposition process. Infrared emission spectroscopy is used to characterize the composition of thin film deposits resulting from the combustion of black liquor and the deposition of submicron aerosols and vapors. New reference spectra of Na{sub 2}SO{sub 4}, K{sub 2}SO{sub 4}, Na{sub 2}CO{sub 3} and K{sub 2}CO{sub 3} pure component films were recorded and compared with the spectra of the black liquor deposit. All of the black liquor emission bands were identified using a combination of literature data and ab initio calculations. Ab initio calculations also predict the locations and intensities of bands for the alkali vapors of interest. 39 refs., 9 figs.

  18. Dynamically self-regular quantum harmonic black holes

    E-Print Network [OSTI]

    Spallucci, Euro

    2015-01-01T23:59:59.000Z

    The recently proposed UV self-complete quantum gravity program is a new and very interesting way to envision Planckian/trans-Planckian physics. in this new framework, high energy scattering is dominated by the creation of micro black holes, and it is experimentally impossible to probe distances shorter than the horizon radius. In this letter we present a model which realizes this idea through the creation of self-regular quantum black holes admitting a minimal size extremal configuration. Their radius provides a dynamically generated minimal length acting as a universal short-distance cut-off. We propose a quantisation scheme for this new kind of microscopic objects based on a Bohr-like approach, which does not require a detailed knowledge of quantum gravity. The resulting black hole quantum picture resembles the energy spectrum of a quantum harmonic oscillator. The mass of the extremal configuration plays the role of zero-point energy. Large quantum number re-establish the classical black hole description. F...

  19. CERTIFICATION of FINANCIAL RESPONSIBILITY USE BLACK INK ONLY

    E-Print Network [OSTI]

    New Mexico, University of

    CERTIFICATION of FINANCIAL RESPONSIBILITY ­ USE BLACK INK ONLY ­ This form is valid during your First or Given Middle Name Suffix COUNTRY OF CITIZENSHIP: DATE OF BIRTH: COUNTRY OF BIRTH: I plan qualifying dependents will accompany me: Name Date of Birth Country of Birth Country of Citizenship

  20. EMERGINGTECHN0 LOGIES COM:MERCIALlZING BLACK

    E-Print Network [OSTI]

    COMMERCIALPRODUC710N REQUIRES WORK AND INVEST~ENT BY MANY PAR11Es. -- B LACK UQUOR AND BIOMASS GASIFIER DEVELOPMENT by the suc- by the U.S.Departmentof Energy(4), providesa mecha- cessful introduction of black liquor gasifier/combined nism for the industry to work togethertoward commer- cycle (BLGCC) and biomass gasifier/combined cycle