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1

Slim Holes | Open Energy Information  

Open Energy Info (EERE)

Slim Holes Slim Holes Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Slim Holes Details Activities (30) Areas (24) Regions (1) NEPA(6) Exploration Technique Information Exploration Group: Drilling Techniques Exploration Sub Group: Exploration Drilling Parent Exploration Technique: Exploration Drilling Information Provided by Technique Lithology: If core is collected Stratigraphic/Structural: If core is collected Hydrological: Fluid flow and water chemistry Thermal: Thermal gradient or bottom hole temperature Cost Information Low-End Estimate (USD): 100.0010,000 centUSD 0.1 kUSD 1.0e-4 MUSD 1.0e-7 TUSD / foot Median Estimate (USD): 169.8916,989 centUSD 0.17 kUSD 1.6989e-4 MUSD 1.6989e-7 TUSD / foot High-End Estimate (USD): 200.0020,000 centUSD

2

Slim Holes for Small Power Plants  

SciTech Connect (OSTI)

Geothermal research study at Sandia National Laboratories has conducted a program in slimhole drilling research since 1992. Although our original interest focused on slim holes as an exploration method, it has also become apparent that they have substantial potential for driving small-scale, off-grid power plants. This paper summarizes Sandia's slim-hole research program, describes technology used in a ''typical'' slimhole drilling project, presents an evaluation of using slim holes for small power plants, and lists some of the research topics that deserve further investigation.

Finger, John T.

1999-08-06T23:59:59.000Z

3

Hydroprobe | Open Energy Information  

Open Energy Info (EERE)

Hydroprobe Hydroprobe Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Hydroprobe Details Activities (2) Areas (2) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Drilling Techniques Exploration Sub Group: Exploration Drilling Parent Exploration Technique: Exploration Drilling Information Provided by Technique Lithology: Stratigraphic/Structural: Hydrological: Collection of ground water samples for geochemistry and geothermometry Thermal: Temperature measurements down to 50 m Dictionary.png Hydroprobe: An exploratory drilling technique focused on collecting geothermal fluid samples from shallow depths at relatively inexpensive costs and low environmental impact. Other definitions:Wikipedia Reegle Introduction A hydroprobe is a relitively inexpensive and easily portable truck mounted

4

Slim Holes At Blue Mountain Area (Warpinski, Et Al., 2002) |...  

Open Energy Info (EERE)

Blue Mountain Area (Warpinski, Et Al., 2002) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Slim Holes At Blue Mountain Area (Warpinski, Et Al.,...

5

Slim Holes At Fort Bliss Area (DOE GTP) | Open Energy Information  

Open Energy Info (EERE)

Fort Bliss Area Exploration Technique Slim Holes Activity Date Usefulness not indicated DOE-funding Unknown Notes 2 slim holes References (1 January 2011) GTP ARRA Spreadsheet...

6

Electrical Generating Capacities of Geothermal Slim Holes  

SciTech Connect (OSTI)

Theoretical calculations are presented to estimate the electrical generating capacity of the hot fluids discharged from individual geothermal wells using small wellhead generating equipment over a wide range of reservoir and operating conditions. The purpose is to appraise the possibility of employing slim holes (instead of conventional production-size wells) to power such generators for remote off-grid applications such as rural electrification in developing countries. Frequently, the generating capacity desired is less than one megawatt, and can be as low as 100 kilowatts; if slim holes can be usefully employed, overall project costs will be significantly reduced. This report presents the final results of the study. Both self-discharging wells and wells equipped with downhole pumps (either of the ''lineshaft'' or the ''submersible'' type) are examined. Several power plant designs are considered, including conventional single-flash backpressure and condensing steam turbines, binary plants, double-flash steam plants, and steam turbine/binary hybrid designs. Well inside diameters from 75 mm to 300 mm are considered; well depths vary from 300 to 1200 meters. Reservoir temperatures from 100 C to 240 C are examined, as are a variety of reservoir pressures and CO2 contents and well productivity index values.

Pritchett, J.W.

1998-10-01T23:59:59.000Z

7

Geothermal slim holes for small off-grid power projects  

Science Journals Connector (OSTI)

Economically viable, small (100 kWe to 1000 kWe), geothermal power generation units using slim holes are available for the production of electrical power in remote areas and for rural electrification in developing countries. Based on borehole data from geothermal fields in the United States and Japan, slim holes have been proven as adequate fuel sources for small-scale geothermal power plants (SSGPPs) and can deliver enough geothermal fluid to the wellhead in a baseload mode to be of practical interest for off-grid electrification projects. The electrical generating capacity of geothermal fluids which can be produced from typical slim holes (150-mm diameter or less), both by conventional, self-discharge, flash-steam methods for hotter geothermal reservoirs, and by binary-cycle technology with downhole pumps for low- to moderate-temperature reservoirs are estimated using a simplified theoretical approach. Depending mainly on reservoir temperature, the numerical simulations indicate that electrical capacities from a few hundred kilowatts to over one megawatt per slim hole are possible. In addition to the advantage of price per kilowatt-hour in off-grid applications, \\{SSGPPs\\} fueled by slim holes are far more environmentally benign than fossil-burning power plants, which is crucial in view of current worldwide climate-change concerns and burgeoning electricity demand in the less-developed and developing countries.

Jim Combs; Sabodh K Garg; John W Pritchett

1997-01-01T23:59:59.000Z

8

Slim Holes At Salt Wells Area (Combs, Et Al., 1999) | Open Energy  

Open Energy Info (EERE)

Slim Holes At Salt Wells Area (Combs, Et Al., 1999) Slim Holes At Salt Wells Area (Combs, Et Al., 1999) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Slim Holes At Salt Wells Area (Combs, Et Al., 1999) Exploration Activity Details Location Salt Wells Area Exploration Technique Slim Holes Activity Date 1980 - 1980 Usefulness useful DOE-funding Unknown Exploration Basis The blind Salt Wells geothermal system was first identified when Anadarko Petroleum Corporation drilled slim hole and geothermal exploration wells at the site in 1980. Two reports detail the results of this drilling activity. This report details the well completion practices applied to the initial slim hole discovery well. Notes In 1980, Anadarko Petroleum Corporation drilled a slim hole discovery well near Simpson Pass. The hole was initially rotary-drilled to 161.5 m for

9

Slim hole drilling proven in remote exploration project  

SciTech Connect (OSTI)

This paper reports on a helicopter-supported slim hole exploration project in a remote tropical forest which cost 15% less than a conventional drilling operation. The potential savings after improvements in rig equipment, bits, and drilling and coring methods may approach 30%. Because of the small size of the slim hole equipment, the impact on the rain forest was small. The areas cleared for locations and access during the operation were 75% less than that required for similar operations with conventional road-transported rigs. During the second half of 1991, Total Exploration Gabon, a subsidiary of Total Exploration Production, conducted a slim hole drilling project in the Gabonese tropical rain forest in a joint venture with Chevron Corp., Exxon Corp., and Austria's OMV AG. During this helicopter-supported operation, two wells were drilled: one to 2,747 m (9,010 ft) ending with a 3 in. hole and one to 418 m (1,371 ft) ending with a 5-7/8 in. hole. Continuous coring operations recovered 1,868 m (6,127 ft), or 59% of the total length drilled.

Dachary, J. (Total Exploration Production, Libreville (GA)); Vighetto, R. (Total Exploration Production, Paris (FR))

1992-06-22T23:59:59.000Z

10

Slim Holes At Glass Buttes Area (DOE GTP) | Open Energy Information  

Open Energy Info (EERE)

navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Slim Holes At Glass Buttes Area (DOE GTP) Exploration Activity Details Location Glass Buttes Area...

11

Slim Holes At Salton Sea Area (Sabin, Et Al., 2010) | Open Energy  

Open Energy Info (EERE)

Slim Holes At Salton Sea Area (Sabin, Et Al., 2010) Slim Holes At Salton Sea Area (Sabin, Et Al., 2010) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Slim Holes At Salton Sea Area (Sabin, Et Al., 2010) Exploration Activity Details Location Salton Sea Area Exploration Technique Slim Holes Activity Date Usefulness not indicated DOE-funding Unknown Notes NAF El Centro work started as a consulting project in 2003. An overlapping TGH and geophysical target prompted GPO to follow up with drilling that was initiated in 2008. Technical problems with both holes has prompted GPO to drill one more deep, slim hole on this anomaly in the summer of 2010. The details of GPO's plans and prior work at NAFEC are available elsewhere in this volume. References Andrew Sabin, S. Bjornstad, M. Lazaro, D. Meade, C. Page, S. Alm, A.

12

Slim Holes At Jemez Pueblo Area (DOE GTP) | Open Energy Information  

Open Energy Info (EERE)

Slim Holes At Jemez Pueblo Area (DOE GTP) Slim Holes At Jemez Pueblo Area (DOE GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Slim Holes At Jemez Pueblo Area (DOE GTP) Exploration Activity Details Location Jemez Pueblo Area Exploration Technique Slim Holes Activity Date Usefulness not indicated DOE-funding Unknown Notes 1 well References (1 January 2011) GTP ARRA Spreadsheet Retrieved from "http://en.openei.org/w/index.php?title=Slim_Holes_At_Jemez_Pueblo_Area_(DOE_GTP)&oldid=402648" Categories: Exploration Activities DOE Funded Activities ARRA Funded Activities What links here Related changes Special pages Printable version Permanent link Browse properties About us Disclaimers Energy blogs Linked Data Developer services OpenEI partners with a broad range of international organizations to grow

13

Slim Holes At Gabbs Valley Area (DOE GTP) | Open Energy Information  

Open Energy Info (EERE)

source source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon » Slim Holes At Gabbs Valley Area (DOE GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Slim Holes At Gabbs Valley Area (DOE GTP) Exploration Activity Details Location Gabbs Valley Area Exploration Technique Slim Holes Activity Date Usefulness not indicated DOE-funding Unknown Notes 2 slim holes References (1 January 2011) GTP ARRA Spreadsheet Retrieved from "http://en.openei.org/w/index.php?title=Slim_Holes_At_Gabbs_Valley_Area_(DOE_GTP)&oldid=402645" Categories: Exploration Activities DOE Funded Activities ARRA Funded Activities

14

Use of Slim Holes for Geothermal Reservoir Assessment: An Update  

SciTech Connect (OSTI)

Production and injection data from slim holes and large-diameter wells in three (3) geothermal fields (Oguni, Sumikawa, Steamboat Hills) were examined to determine the effect of borehole diameter (1) on the discharge rate and (2) on the productivity/injectivity indices. For boreholes with liquid feedzones, maximum discharge rates scale with diameter according to a relationship previously derived by Pritchett. The latter scaling rule does not apply to discharge data for boreholes with two-phase feedzones. Data from Oguni and Sumikawa geothermal fields indicate that the productivity (for boreholes with liquid feeds) and injectivity indices are more or less equal. The injectivity indices for Sumikawa boreholes are essentially independent of borehole diameter. The latter result is at variance with Oguni data; both the productivity and injectivity indices for Oguni boreholes display a strong variation with borehole diameter. Based on the discharge and injection data from these three geothermal fields, the flow rate of large-diameter production wells with liquid feedzones can be predicted using data from slim holes.

Garg, S.K.; Combs, J.; Goranson, C.

1995-01-01T23:59:59.000Z

15

Slim Holes At Hawthorne Area (Sabin, Et Al., 2010) | Open Energy  

Open Energy Info (EERE)

Slim Holes At Hawthorne Area (Sabin, Et Al., 2010) Slim Holes At Hawthorne Area (Sabin, Et Al., 2010) Exploration Activity Details Location Hawthorne Area Exploration Technique Slim Holes Activity Date Usefulness useful DOE-funding Unknown Notes GPO drilled two deep, slim geophysical test holes on the western margin of the Hawthorne Army Depot in 2008/2009. These two holes, HWAD 2a and HWAD 3, were drilled on the perceived structural trend of this valley and immediately south and east, respectively, of the El Capitan well. The "El Cap" is a 1,000' well completed by an unsuccessful developer in 1980. The El Cap and several other wells in this region south of Walker Lake have long been admired and even discussed by industry and the military but no sustained exploration or development activities work have ever been

16

Slim Holes At Fish Lake Valley Area (Deymonaz, Et Al., 2008) | Open Energy  

Open Energy Info (EERE)

Slim Holes At Fish Lake Valley Area (Deymonaz, Et Al., 2008) Slim Holes At Fish Lake Valley Area (Deymonaz, Et Al., 2008) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Slim Holes At Fish Lake Valley Area (Deymonaz, Et Al., 2008) Exploration Activity Details Location Fish Lake Valley Area Exploration Technique Slim Holes Activity Date Usefulness not indicated DOE-funding Unknown Notes Esmeralda Energy Company (EEC) intends to drill a core hole to a maximum depth of 4,000 feet on its Emigrant Project in Fish Lake Valley, Esmeralda County, Nevada. The drilling project is the key component in phased program of resource evaluation by EEC References John Deymonaz, Jeffrey G. Hulen, Gregory D. Nash, Alex Schriener (2008) Esmeralda Energy Company Final Scientific Technical Report, January

17

Slim Holes At Newberry Caldera Area (DOE GTP) | Open Energy Information  

Open Energy Info (EERE)

source source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon » Slim Holes At Newberry Caldera Area (DOE GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Slim Holes At Newberry Caldera Area (DOE GTP) Exploration Activity Details Location Newberry Caldera Area Exploration Technique Slim Holes Activity Date Usefulness not indicated DOE-funding Unknown References (1 January 2011) GTP ARRA Spreadsheet Retrieved from "http://en.openei.org/w/index.php?title=Slim_Holes_At_Newberry_Caldera_Area_(DOE_GTP)&oldid=402651" Categories: Exploration Activities DOE Funded Activities ARRA Funded Activities

18

Slim Holes At Blue Mountain Area (Fairbank Engineering, 2009) | Open Energy  

Open Energy Info (EERE)

Fairbank Engineering, 2009) Fairbank Engineering, 2009) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Slim Holes At Blue Mountain Area (Fairbank Engineering, 2009) Exploration Activity Details Location Blue Mountain Area Exploration Technique Slim Holes Activity Date Usefulness useful DOE-funding Unknown Notes DEEP BLUE No.1, the first slim geothermal observation test hole at Blue Mountain, was drilled under a cost-share program between the DOE and Noramex, under the DOE's Geothermal Resource Exploration and Definition (GRED) program, (Noramex Corp., 2002). The hole was sited to test an area of projected high temperature at depth from gradients measured in shallow holes drilled in the central part of the lease area (Figure 3.1), and to test an area of low apparent resistivity interpreted to reflect possible

19

Slim Holes At Steamboat Springs Area (Warpinski, Et Al., 2002) | Open  

Open Energy Info (EERE)

2) 2) Exploration Activity Details Location Steamboat Springs Area Exploration Technique Slim Holes Activity Date Usefulness useful DOE-funding Unknown Notes Stratigraphic slim hole 24-33 was drilled in a lease area south of current production during March 2001. The well was continuously cored from 235 m to the total depth of 610 m. Several fracture zones were encountered with noticeably large fracture apertures and the maximum recorded temperature was comparable to nearby productive wells. A second well, slim hole 12-33, was drilled to a total depth of 297 m during April 2001. Continuous core was taken from 152 m to total depth. Numerous open fractures were also observed in this well and the maximum recorded temperature was similar to the 24-33 well. References

20

Slim Holes At Vale Hot Springs Area (Combs, Et Al., 1999) | Open Energy  

Open Energy Info (EERE)

Slim Holes At Vale Hot Springs Area (Combs, Et Al., Slim Holes At Vale Hot Springs Area (Combs, Et Al., 1999) Exploration Activity Details Location Vale Hot Springs Area Exploration Technique Slim Holes Activity Date Usefulness useful DOE-funding Unknown Notes In April-May 1995, Sandia drilled a cost-shared exploratory slimhole with Trans-Pacific Geothermal Corporation (TGC), which owns leases in the Vale KGIL4. In addition to possible discovery of a new geothermal resource, this situation offered an opportunity for direct cost comparison between an exploration sl.irnholedrilled with "hybrid" techniques on a diamond-coring rig and a previous exploration well, which was conventionally drilled but would be considered a slimhole in that technology. References Jim Combs, John T. Finger, Colin Goranson, Charles E. Hockox Jr.,

Note: This page contains sample records for the topic "hydroprobe slim holes" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Slim Holes At International Geothermal Area, Japan (Combs, Et Al., 1999) |  

Open Energy Info (EERE)

Japan (Combs, Et Al., 1999) Japan (Combs, Et Al., 1999) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Slim Holes At International Geothermal Area, Japan (Combs, Et Al., 1999) Exploration Activity Details Location International Geothermal Area Japan Exploration Technique Slim Holes Activity Date Usefulness useful DOE-funding Unknown Notes Based on personal relationships between Maxwell scientists and Japanese geothermal developers, production and injection data from 64 slim holes and 79 large-diameter wells (see table below) at four Japanese geothermal fields (Oguni, Sumikaw~ Takigarni, and Kirishirna) have been obtained. References Jim Combs, John T. Finger, Colin Goranson, Charles E. Hockox Jr., Ronald D. Jacobsen, Gene Polik (1999) Slimhole Handbook- Procedures And

22

Preliminary estimates of electrical generating capacity of slim holes--a theoretical approach  

SciTech Connect (OSTI)

The feasibility of using small geothermal generators (< 1 MWe) for off-grid electrical power in remote areas or for rural electrification in developing nations would be enhanced if drilling costs could be reduced. This paper examines the electrical generating capacity of fluids which can be produced from typical slim holes (six-inch diameter or less), both by binary techniques (with downhole pumps) and, for hotter reservoir fluids, by conventional spontaneous-discharge flash-steam methods. Depending mainly on reservoir temperature, electrical capacities from a few hundred kilowatts to over one megawatt per slim hole appear to be possible.

Pritchett, John W.

1995-01-26T23:59:59.000Z

23

Slim Holes At Alvord Hot Springs Area (Combs, Et Al., 1999) | Open Energy  

Open Energy Info (EERE)

Combs, Et Al., 1999) Combs, Et Al., 1999) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Slim Holes At Alvord Hot Springs Area (Combs, Et Al., 1999) Exploration Activity Details Location Alvord Hot Springs Area Exploration Technique Slim Holes Activity Date Usefulness not indicated DOE-funding Unknown Notes Anadarko Petroleum Corporation drilled two slimhole discoveries in the 1980s, one at Salt Wells, NV, and the other at Pueblo Valley, OR. Both of these slimholes were hot enough to discharge unassisted and were successfully flow tested. A slimhole at Pueblo Valley, in south-east Oregon was planned and permitted as a test well to evaluate an interval of fractured basalt which had been discovered while drilling an earlier thermal-gradient hole. Using a UDR1500 rig, the hole was rotary-drilled to

24

Slim Holes At Fort Bliss Area (Combs, Et Al., 1999) | Open Energy  

Open Energy Info (EERE)

Fort Bliss Area (Combs, Et Al., 1999) Fort Bliss Area (Combs, Et Al., 1999) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Slim Holes At Fort Bliss Area (Combs, Et Al., 1999) Exploration Activity Details Location Fort Bliss Area Exploration Technique Slim Holes Activity Date Usefulness useful DOE-funding Unknown Notes When the U. S. Army was in the planning stages for a geothermal exploration program at Ft. Bliss, they approached the Geothermal Research Department for input on the structure of this progrm, this consultation led to a Work-for-Others (WFO) contract from the Army to Sandia for assistance on the exploratory holes. That assistance included consultation and dmection of drilling operations, numerous temperature logs during and after drilling, and project documentation. This report comprises a summary of

25

Slim Holes At Blue Mountain Area (Warpinski, Et Al., 2004) | Open Energy  

Open Energy Info (EERE)

Blue Mountain Area (Warpinski, Et Al., Blue Mountain Area (Warpinski, Et Al., 2004) Exploration Activity Details Location Blue Mountain Area Exploration Technique Slim Holes Activity Date Usefulness not indicated DOE-funding Unknown Notes Update to Warpinski, et al., 2002 References N. R. Warpinski, A. R. Sattler, R. Fortuna, D. A. Sanchez, J. Nathwani (2004) Geothermal Resource Exploration And Definition Projects Retrieved from "http://en.openei.org/w/index.php?title=Slim_Holes_At_Blue_Mountain_Area_(Warpinski,_Et_Al.,_2004)&oldid=387371" Categories: Exploration Activities DOE Funded Activities What links here Related changes Special pages Printable version Permanent link Browse properties About us Disclaimers Energy blogs Linked Data Developer services OpenEI partners with a broad range of international organizations to grow

26

Slim Holes At Reese River Area (Henkle & Ronne, 2008) | Open Energy  

Open Energy Info (EERE)

Reese River Area (Henkle & Ronne, 2008) Reese River Area (Henkle & Ronne, 2008) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Slim Holes At Reese River Area (Henkle & Ronne, 2008) Exploration Activity Details Location Reese River Area Exploration Technique Slim Holes Activity Date Usefulness useful DOE-funding Unknown Notes Well RR 56-4, was not successful in intersecting an exploitable geothermal resource. However, the lack of temperature reversal in the well and the geochemistry information obtained from fluid sampling point towards a large resource of moderate temperature. The encouraging results from 56-4 have lead to continued exploration on the project. The geologic and hydrologic information collected from 56-4 has proved an invaluable aid when combined

27

Slim Holes At Newberry Caldera Area (Combs, Et Al., 1999) | Open Energy  

Open Energy Info (EERE)

Newberry Caldera Area (Combs, Et Al., Newberry Caldera Area (Combs, Et Al., 1999) Exploration Activity Details Location Newberry Caldera Area Exploration Technique Slim Holes Activity Date Usefulness useful DOE-funding Unknown Notes Negotiations with California Energy Company, Incorporated (CECI), which owns leases in the Newberry KGRA led to an agreement for a cost-shared exploratory drilling project on CECI'Slease. In return for the cost-share, Sandia was to receive testing, production and cost data from the slhnholes and from the production wells drilled nearby, giving a direct comparison of productivity predicted from tests on the slimholes and that achieved by the actual production wells. Since locations, depths and lithology are also similar, there would also be a close comparison of drilling costs.

28

A study of production/injection data from slim holes and large-diameter wells at the Takigami Geothermal Field, Kyushu, Japan  

SciTech Connect (OSTI)

Production and injection data from nine slim holes and sixteen large-diameter wells at the Takigami Geothermal Field, Kyushu, Japan were analyzed in order to establish relationships (1) between injectivity and productivity indices, (2) between productivity/injectivity index and borehole diameter, and (3) between discharge capacity of slim holes and large-diameter wells. Results are compared with those from the Oguni and Sumikawa fields. A numerical simulator (WELBOR) was used to model the available discharge rate from Takigami boreholes. The results of numerical modeling indicate that the flow rate of large-diameter geothermal production wells with liquid feedzones can be predicted using data from slim holes. These results also indicate the importance of proper well design.

Garg, S.K. [Maxwell Federal Div., Inc., San Diego, CA (United States)] [Maxwell Federal Div., Inc., San Diego, CA (United States); Combs, J. [Geo-Hills Associates, Los Altos Hills, CA (United States)] [Geo-Hills Associates, Los Altos Hills, CA (United States); Azawa, Fumio [Idemitsu Kosan Co. Ltd., Tokyo (Japan)] [Idemitsu Kosan Co. Ltd., Tokyo (Japan); Gotoh, Hiroki [Idemitsu Oita Geothermal Co. Ltd., Oita (Japan)] [Idemitsu Oita Geothermal Co. Ltd., Oita (Japan)

1996-11-01T23:59:59.000Z

29

Preliminary study of discharge characteristics of slim holes compared to production wells in liquid-dominated geothermal reservoirs  

SciTech Connect (OSTI)

There is current interest in using slim holes for geothermal exploration and reservoir assessment. A major question that must be addressed is whether results from flow or injection testing of slim holes can be scaled to predict large diameter production well performance. This brief report describes a preliminary examination of this question from a purely theoretical point of view. The WELBOR computer program was used to perform a series of calculations of the steady flow of fluid up geothermal boreholes of various diameters at various discharge rates. Starting with prescribed bottomhole conditions (pressure, enthalpy), the WELBOR code integrates the equations expressing conservation of mass, momentum and energy (together with fluid constitutive properties obtained from the steam tables) upwards towards the wellhead using numerical techniques. This results in computed profiles of conditions (pressure, temperature, steam volume fraction, etc.) as functions of depth within the flowing well, and also in a forecast of wellhead conditions (pressure, temperature, enthalpy, etc.). From these results, scaling rules are developed and discussed.

Pritchett, J.W. [S-Cubed, La Jolla, CA (United States)

1993-06-01T23:59:59.000Z

30

A Study of Production/Injection Data from Slim Holes and Large-Diameter Wells at the Okuaizu Geothermal Field, Tohoku, Japan  

SciTech Connect (OSTI)

Discharge from the Okuaizu boreholes is accompanied by in situ boiling. Analysis of cold-water injection and discharge data from the Okuaizu boreholes indicates that the two-phase productivity index is about an order of magnitude smaller than the injectivity index. The latter conclusion is in agreement with analyses of similar data from Oguni, Sumikawa, and Kirishima geothermal fields. A wellbore simulator was used to examine the effect of borehole diameter on the discharge capacity of geothermal boreholes with two-phase feedzones. Based on these analyses, it appears that it should be possible to deduce the discharge characteristics of largediameter wells using test data from slim holes with two-phase feeds.

Renner, Joel Lawrence; Garg, Sabodh K.; Combs, Jim

2002-06-01T23:59:59.000Z

31

High Precision Geophysics & Detailed Structural Exploration & Slim Well  

Open Energy Info (EERE)

Precision Geophysics & Detailed Structural Exploration & Slim Well Precision Geophysics & Detailed Structural Exploration & Slim Well Drilling Geothermal Project Jump to: navigation, search Last modified on July 22, 2011. Project Title High Precision Geophysics & Detailed Structural Exploration & Slim Well Drilling Project Type / Topic 1 Recovery Act: Geothermal Technologies Program Project Type / Topic 2 Validation of Innovative Exploration Technologies Project Description Existing geologic data show that the basalt has been broken by complex intersecting fault zones at the hot springs. Natural state hot water flow patterns in the fracture network will be interpreted from temperature gradient wells and then tested with moderate depth core holes. Production and injection well tests of the core holes will be monitored with an innovative combination of Flowing Differential Self-Potential (FDSP) and resistivity tomography surveys. The cointerpretation of all these highly detailed geophysical methods sensitive to fracture permeability patterns and water flow during the well tests will provide unprecedented details on the structures and flow in a shallow geothermal aquifer and support effective development of the low temperature reservoir and identification of deep up flow targets.

32

New PDC bit design increased penetration rate in slim wells  

SciTech Connect (OSTI)

This paper describes slim hole bit design developed at the Paris School of Mines and Security DBS. The design is a compromise between several criteria such as drilling efficiency, uniform wear distribution around the bit face and low level of vibration of the bit, according to the hole diameter and the formation characteristics. Two new bits were manufactured and run successfully in a full scale drilling test bench and in field test in Gabon. The result show improvement of the drilling performances in slimhole application.

Gerbaud, L.; Sellami, H. [Paris School of Mines (France); Lamine, E.; Sagot, A.

1997-07-01T23:59:59.000Z

33

Slim wells for exploration purposes in Mexico  

SciTech Connect (OSTI)

To invest in the construction of wells with definitive designs considerably increases the cost of a geothermal electric project in its analysis and definition stage. The Federal Commission for Electricity (Comision Federal de Electricidad, CFE) has concentrated on the task to design wells which casing and cementing programs would provide the minimum installation necessary to reach the structural objective, to confirm the existence of geothermal reservoirs susceptible to commercial exploitation, to check prior geological studies, to define the stratigraphic column and to obtain measurements of pressure, temperature and permeability. Problems of brittle, hydratable and permeable formations with severe circulation losses, must be considered within the design and drilling programs of the wells. This work explains the slim wells designs used in the exploration of three geothermal zones in Mexico: Las Derrumbadas and Acoculco in the State of Puebla and Los Negritos in the State of Michoacan.

Vaca Serrano, J.M.E.; Soto Alvarez, M.

1996-12-31T23:59:59.000Z

34

Simulation of Electric Potentials and Ion Motion in Planar Electrode Structures for Lossless Ion Manipulations (SLIM)  

Science Journals Connector (OSTI)

We report a conceptual study and computational evaluation of novel planar electrode structures for lossless ion manipulations (SLIM). Planar electrode SLIM components were designed that allow for flexible ion ...

Sandilya V. B. Garimella; Yehia M. Ibrahim

2014-11-01T23:59:59.000Z

35

Classroom Assignment using Constraint Logic Programming Slim Abdennadher, Matthias Saft and Sebastian Will  

E-Print Network [OSTI]

Classroom Assignment using Constraint Logic Programming Slim Abdennadher, Matthias Saft fabdennad, saft, willsg@informatik.uni­muenchen.de Abstract The Classroom Assignment problem consists

Will, Sebastian

36

1. Slim Haddad Universit de Montral slim.haddad@umontreal.ca 2. Duncan Pedersen McGill University/ Douglas Hospital duncan.pedersen@mcgill.ca  

E-Print Network [OSTI]

1. Slim Haddad Université de Montréal slim.haddad@umontreal.ca 2. Duncan Pedersen McGill University/ Douglas Hospital duncan.pedersen@mcgill.ca 3. Marc Lucotte UQAM lucotte.marc_michel@uqam.ca 4. Pierre Fournier Université de Montréal pierre.fournier@umontreal.ca 5. Eric Dewailly Université Laval eric.Dewailly@crchul.ulaval.ca

Barthelat, Francois

37

Phase 2 Reese River Geothermal Project Slim Well 56-4 Drilling And Testing  

Open Energy Info (EERE)

Phase 2 Reese River Geothermal Project Slim Well 56-4 Drilling And Testing Phase 2 Reese River Geothermal Project Slim Well 56-4 Drilling And Testing Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Report: Phase 2 Reese River Geothermal Project Slim Well 56-4 Drilling And Testing Details Activities (6) Areas (1) Regions (0) Abstract: This report covers the drilling and testing of the slim well 56-4 at the Reese River Geothermal Project in Lander County, Nevada. This well was partially funded through a GRED III Cooperative Funding Agreement # DE-FC36-04GO14344, from USDOE. Author(s): William R. Henkle, Joel Ronne Published: Geothermal Technologies Legacy Collection, 2008 Document Number: Unavailable DOI: Unavailable Source: View Original Report Compound and Elemental Analysis At Reese River Area (Henkle & Ronne, 2008)

38

SLIM AND TRIM WITH SUCCULENT SEAFOOD SO,you've been trying to "diet in quiet" as  

E-Print Network [OSTI]

50 SLIM AND TRIM WITH SUCCULENT SEAFOOD SO,you've been trying to "diet in quiet" as Odgen Nash products can slim and trim you while you enjoy every luscious bite. The rea- son is that seafood are high planned for dieters, not those loaded with but- ter or sauces. Give ve r sat i I e seafoods a chance

39

SLIM at LHC: LHC search power for a model linking dark matter and neutrino mass  

Science Journals Connector (OSTI)

Recently a model has been proposed that links dark matter and neutrino masses. The dark matter candidate which is dubbed as SLIM has a mass of MeV scale and can show up at low energy experiments. The model als...

Y. Farzan; M. Hashemi

2010-11-01T23:59:59.000Z

40

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

Open Energy Info (EERE)

Warrior: Sub-soil Gas and Fluid Inclusion Exploration and Slim Well Warrior: Sub-soil Gas and Fluid Inclusion Exploration and Slim Well Drilling Geothermal Project Jump to: navigation, search Last modified on July 22, 2011. Project Title Black Warrior: Sub-soil Gas and Fluid Inclusion Exploration and Slim Well Drilling Project Type / Topic 1 Recovery Act: Geothermal Technologies Program Project Type / Topic 2 Validation of Innovative Exploration Technologies Project Description The project area encompasses 6,273 acres of both private and federal lands including water and surface rights. It is reasonable to expect a capacity of about 20 MW. GeothermEx estimated a potential capacity of 40 MW. Black Warrior is a large blind geothermal prospect near the Pyramid Lake Indian Reservation that was 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 of high heat flow in the area reveals significant energy potential it also makes selection of an optimal exploration drilling target difficult.

Note: This page contains sample records for the topic "hydroprobe slim holes" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Core Holes At Steamboat Springs Area (Warpinski, Et Al., 2002) | Open  

Open Energy Info (EERE)

2) 2) Exploration Activity Details Location Steamboat Springs Area Exploration Technique Core Holes Activity Date Usefulness not indicated DOE-funding Unknown Notes Stratigraphic slim hole 24-33 was drilled in a lease area south of current production during March 2001. The well was continuously cored from 235 m to the total depth of 610 m. Several fracture zones were encountered with noticeably large fracture apertures and the maximum recorded temperature was comparable to nearby productive wells. A second well, slim hole 12-33, was drilled to a total depth of 297 m during April 2001. Continuous core was taken from 152 m to total depth. Numerous open fractures were also observed in this well and the maximum recorded temperature was similar to the 24-33 well.

42

Thermal Gradient Holes At Twenty-Nine Palms Area (Sabin, Et Al., 2010) |  

Open Energy Info (EERE)

Thermal Gradient Holes At Twenty-Nine Palms Area (Sabin, Et Al., 2010) Thermal Gradient Holes At Twenty-Nine Palms Area (Sabin, Et Al., 2010) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Thermal Gradient Holes At Twenty-Nine Palms Geothermal Area (Sabin, Et Al., 2010) Exploration Activity Details Location Twenty-Nine Palms Geothermal Area Exploration Technique Thermal Gradient Holes Activity Date Usefulness useful DOE-funding Unknown Notes The first and only Seabee drilling project was the installation of five TGHs at the Camp Wilson region of the MCAGCC Marine base near Twenty-Nine Palms, CA. While the program was a success and GPO identified an anomaly where a deep, slim hole is to be drilled in June, 2010, the Seabee rig was sent oversees soon after drilling was completed. If/when another rig

43

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

Broader source: Energy.gov [DOE]

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

44

White holes and eternal black holes  

E-Print Network [OSTI]

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.

Stephen D. H. Hsu

2011-11-16T23:59:59.000Z

45

Black Hole Horizons and Black Hole Thermodynamics.  

E-Print Network [OSTI]

??This work investigates how black holes can be described in terms of different definitions of horizons. Global definitions in terms of event horizons and Killing (more)

Nielsen, Alex

2007-01-01T23:59:59.000Z

46

Calibration of a Neutron Hydroprobe for Moisture Measurements in Small-Diameter Steel-Cased Boreholes  

SciTech Connect (OSTI)

Computation of soil moisture content from thermalized neutron counts for the T-Farm Interim cover requires a calibration relationship but none exists for 2-in tubes. A number of calibration options are available for the neutron probe, including vendor calibration, field calibration, but none of these methods were deemed appropriate for the configuration of interest. The objective of this work was to develop a calibration relation for converting neutron counts measured in 2-in access tubes to soil water content. The calibration method chosen for this study was a computational approach using the Monte Carlo N-Particle Transport Code (MCNP). Model calibration was performed using field measurements in the Hanford calibration models with 6-in access tubes, in air and in the probe shield. The bet-fit model relating known water content to measured neutron counts was an exponential model that was essentially equivalent to that currently being used for 6-in steel cased wells. The MCNP simulations successfully predicted the neutron count rate for the neutron shield and the three calibration models for which data were collected in the field. However, predictions for air were about 65% lower than the measured counts . This discrepancy can be attributed to uncertainties in the configuration used for the air measurements. MCNP-simulated counts for the physical models were essentially equal to the measured counts with values. Accurate prediction of the response in 6-in casings in the three calibration models was motivation to predict the response in 2-in access tubes. Simulations were performed for six of the seven calibration models as well as 4 virtual models with the entire set covering a moisture range of 0 to 40%. Predicted counts for the calibration models with 2-in access tubes were 40 to 50% higher than in the 6-inch tubes. Predicted counts for water were about 60% higher in the 2-in tube than in the 6-in tube. The discrepancy between the 2-in and 6-in tube can be attributed to the smaller air gap between the probe and the 2-in access tube. The best-fit model relating volumetric water content to count ratio (CR) is of the form e^A x CR^B with A=0.3596 0.0216 and B=0.4629 0.0629 and r^2= 0.9998. It is recommended that the calibration function based on the count ratio, rather than raw counts, be used to avoid the effects of electronic noise in the probe that may arise due to the conditions at the time of measurement. These results suggest that the MCNP code can be used to extend calibrations for the neutron probe to different conditions including access tube size as well as composition without the need to construct additional physical models.

Ward, Anderson L.; Wittman, Richard S.

2009-08-01T23:59:59.000Z

47

Black Hole Chemistry  

E-Print Network [OSTI]

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.

David Kubiznak; Robert B. Mann

2014-04-08T23:59:59.000Z

48

Black holes and thermodynamics  

Science Journals Connector (OSTI)

A black hole of given mass, angular momentum, and charge can have a large number of different unobservable internal configurations which reflect the possible different initial configurations of the matter which collapsed to produce the hole. The logarithm of this number can be regarded as the entropy of the black hole and is a measure of the amount of information about the initial state which was lost in the formation of the black hole. If one makes the hypothesis that the entropy is finite, one can deduce that the black holes must emit thermal radiation at some nonzero temperature. Conversely, the recently derived quantum-mechanical result that black holes do emit thermal radiation at temperature ??2? k c, where ? is the surface gravity, enables one to prove that the entropy is finite and is equal to c3A4 G?, where A is the surface area of the event horizon or boundary of the black hole. Because black holes have negative specific heat, they cannot be in stable thermal equilibrium except when the additional energy available is less than 1/4 the mass of the black hole. This means that the standard statistical-mechanical canonical ensemble cannot be applied when gravitational interactions are important. Black holes behave in a completely random and time-symmetric way and are indistinguishable, for an external observer, from white holes. The irreversibility that appears in the classical limit is merely a statistical effect.

S. W. Hawking

1976-01-15T23:59:59.000Z

49

RHIC | Black Holes?  

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

Black Holes at RHIC? Black Holes at RHIC? Further discussion by Physicist Dmitri Kharzeev on why RHIC cannot produce a real gravitational black hole Black holes are among the most mysterious objects in the universe. The gravitational field of a black hole is so strong that Einstein's general relativity tells us that nothing, not even light, can escape from the black hole's interior. However, in 1974 physicist Stephen Hawking demonstrated that black holes must emit radiation once the quantum effects are included. According to quantum mechanics, the physical vacuum is bubbling with short-lived virtual particle-antiparticle pairs. Creation of a particle-antiparticle pair from the vacuum conflicts with energy conservation, but energy need not be conserved at short times in quantum mechanics, according to Heisenberg's

50

Uniformly accelerated black holes  

Science Journals Connector (OSTI)

The static and stationary C metric are examined in a generic framework and their interpretations studied in some detail, especially those with two event horizons, one for the black hole and another for the acceleration. We find that (i) the spacetime of an accelerated static black hole is plagued by either conical singularities or a lack of smoothness and compactness of the black hole horizon, (ii) by using standard black hole thermodynamics we show that accelerated black holes have a higher Hawking temperature than Unruh temperature of the accelerated frame, and (iii) the usual upper bound on the product of the mass and acceleration parameters (<1/27) is just a coordinate artifact. The main results are extended to accelerated rotating black holes with no significant changes.

Patricio S. Letelier and Samuel R. Oliveira

2001-08-24T23:59:59.000Z

51

Accreting Black Holes  

E-Print Network [OSTI]

I outline the theory of accretion onto black holes, and its application to observed phenomena such as X-ray binaries, active galactic nuclei, tidal disruption events, and gamma-ray bursts. The dynamics as well as radiative signatures of black hole accretion depend on interactions between the relatively simple black-hole spacetime and complex radiation, plasma and magnetohydrodynamical processes in the surrounding gas. I will show how transient accretion processes could provide clues to these interactions. Larger global magnetohydrodynamic simulations as well as simulations incorporating plasma microphysics and full radiation hydrodynamics will be needed to unravel some of the current mysteries of black hole accretion.

Begelman, Mitchell C

2014-01-01T23:59:59.000Z

52

"Hybrid" Black Holes  

E-Print Network [OSTI]

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.

Valeri P. Frolov; Andrei V. Frolov

2014-12-30T23:59:59.000Z

53

Entropy of quasiblack holes  

SciTech Connect (OSTI)

We trace the origin of the black hole entropy S, replacing a black hole by a quasiblack hole. Let the boundary of a static body approach its own gravitational radius, in such a way that a quasihorizon forms. We show that if the body is thermal with the temperature taking the Hawking value at the quasihorizon limit, it follows, in the nonextremal case, from the first law of thermodynamics that the entropy approaches the Bekenstein-Hawking value S=A/4. In this setup, the key role is played by the surface stresses on the quasihorizon and one finds that the entropy comes from the quasihorizon surface. Any distribution of matter inside the surface leads to the same universal value for the entropy in the quasihorizon limit. This can be of some help in the understanding of black hole entropy. Other similarities between black holes and quasiblack holes such as the mass formulas for both objects had been found previously. We also discuss the entropy for extremal quasiblack holes, a more subtle issue.

Lemos, Jose P. S.; Zaslavskii, Oleg B. [Centro Multidisciplinar de Astrofisica-CENTRA, Departamento de Fisica, Instituto Superior Tecnico-IST, Universidade Tecnica de Lisboa-UTL, Avenida Rovisco Pais 1, 1049-001 Lisboa (Portugal); Astronomical Institute of Kharkov, V. N. Karazin National University, 35 Sumskaya Street, Kharkov, 61022 (Ukraine)

2010-03-15T23:59:59.000Z

54

RHIC | Black Holes?  

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

Black Holes at RHIC? Black Holes at RHIC? Before RHIC began operations in 2000, some were concerned that it would produce black holes that would threaten the earth. Here's why those concerns were unfounded. Committee Review of Speculative "Disaster Scenarios" at RHIC In July 1999, Brookhaven Lab Director John Marburger convened a committee of distinguished physicists to write a comprehensive report on the arguments that address the safety of speculative disaster scenarios at RHIC. The scenarios are: Creation of a black hole that would "eat" ordinary matter. Initiation of a transition to a new, more stable universe. Formation of a "strangelet" that would convert ordinary matter to a new form. jaffee "We conclude that there are no credible mechanisms for catastrophic

55

Charged Schrodinger black holes  

E-Print Network [OSTI]

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, ...

Adams, Allan

56

Holes in Spectral Lines  

E-Print Network [OSTI]

The decay of an atom in the presence of a static perturbation is investigated. The perturbation couples a decaying state with a nondecaying state. A "hole" appears in the emission line at a frequency equal to the frequency ...

Fontana, Peter R.; Srivastava, Rajendra P.

1973-06-01T23:59:59.000Z

57

On Black Hole Entropy  

E-Print Network [OSTI]

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.}

Ted Jacobson; Gungwon Kang; Robert C. Myers

1994-01-03T23:59:59.000Z

58

Core Holes | Open Energy Information  

Open Energy Info (EERE)

Core Holes Core Holes Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Core Holes Details Activities (8) Areas (7) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Drilling Techniques Exploration Sub Group: Exploration Drilling Parent Exploration Technique: Exploration Drilling Information Provided by Technique Lithology: Core holes are drilled to identify lithology and mineralization Stratigraphic/Structural: Retrieved samples can be used to identify fracture networks or faults Hydrological: Thermal: Thermal conductivity measurements can be done on retrieved samples. Dictionary.png Core Holes: A core hole is a well that is drilled using a hallow drill bit coated with synthetic diamonds for the purposes of extracting whole rock samples from

59

Black holes at accelerators.  

E-Print Network [OSTI]

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...

Webber, Bryan R

60

Inside a black hole  

Science Journals Connector (OSTI)

... interior. These models reveal several significantly different behaviours. The simplest model, of a 'Schwarzschild' black hole, which possesses mass but no charge or angular momentum, has an ... into account, seal off the 'tunnel', and yield an interior similar to the Schwarzschild model, with an all-encompassing crushing singularity. More recently, there have been attempts6- ...

William A. Hiscock

1991-10-24T23:59:59.000Z

Note: This page contains sample records for the topic "hydroprobe slim holes" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Laser bottom hole assembly  

DOE Patents [OSTI]

There is provided for laser bottom hole assembly for providing a high power laser beam having greater than 5 kW of power for a laser mechanical drilling process to advance a borehole. This assembly utilizes a reverse Moineau motor type power section and provides a self-regulating system that addresses fluid flows relating to motive force, cooling and removal of cuttings.

Underwood, Lance D; Norton, Ryan J; McKay, Ryan P; Mesnard, David R; Fraze, Jason D; Zediker, Mark S; Faircloth, Brian O

2014-01-14T23:59:59.000Z

62

Supermassive Black Holes  

E-Print Network [OSTI]

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.

Fulvio Melia

2007-05-10T23:59:59.000Z

63

Black hole lasers  

Science Journals Connector (OSTI)

High frequency dispersion does not alter the low frequency spectrum of Hawking radiation from a single black hole horizon, whether the dispersion entails subluminal or superluminal group velocities. We show here that in the presence of an inner horizon as well as an outer horizon the superluminal case differs dramatically however. The negative energy partners of Hawking quanta return to the outer horizon and stimulate more Hawking radiation if the field is bosonic or suppress it if the field is fermionic. This process leads to exponential growth or damping of the radiated flux and correlations among the quanta emitted at different times, unlike in the usual Hawking effect. These phenomena may be observable in condensed matter black hole analogues that exhibit superluminal dispersion.

Steven Corley and Ted Jacobson

1999-05-17T23:59:59.000Z

64

Black Holes And Their Entropy  

E-Print Network [OSTI]

This dissertation covers two di erent but related topics: the construction of new black hole solutions and the study of the microscopic origin of black hole entropy. In the solution part, two di erent sets of new solutions are found. The rst...

Mei, Jianwei

2010-10-12T23:59:59.000Z

65

Black Hole Energy Extraction Problems  

Science Journals Connector (OSTI)

... non-rotating black hole the particle can be lowered to no closer than 1.14 Schwarzschild radii, and the energy extracted can be no more than 63.2 per cent ... gram of matter-and the rope could be lowered no closer than 5 x 1011 Schwarzschild radii. This seems to rule out black holes as practical sources of energy. ...

1972-11-24T23:59:59.000Z

66

Optical black holes and solitons  

E-Print Network [OSTI]

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.

Shawn Westmoreland

2010-12-21T23:59:59.000Z

67

Entropy of Lovelock Black Holes  

E-Print Network [OSTI]

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.

Ted Jacobson; Robert C. Myers

1993-05-06T23:59:59.000Z

68

String-Corrected Black Holes  

SciTech Connect (OSTI)

We investigate the geometry of four dimensional black hole solutions in the presence of stringy higher curvature corrections to the low energy effective action. For certain supersymmetric two charge black holes these corrections drastically alter the causal structure of the solution, converting seemingly pathological null singularities into timelike singularities hidden behind a finite area horizon. We establish, analytically and numerically, that the string-corrected two-charge black hole metric has the same Penrose diagram as the extremal four-charge black hole. The higher derivative terms lead to another dramatic effect -- the gravitational force exerted by a black hole on an inertial observer is no longer purely attractive! The magnitude of this effect is related to the size of the compactification manifold.

Hubeny, Veronika; Maloney, Alexander; Rangamani, Mukund

2005-02-07T23:59:59.000Z

69

The structure of black hole magnetospheres I. Schwarzschild black holes  

Science Journals Connector (OSTI)

......2000 RAS, MNRAS 315, 89 97 force-free black hole magnetosphere...However, there is nothing fundamental about the paraboloidal shape...in stationary axisymmetric force-free magnetospheres. Therefore...Stegun I. A., 1972, Handbook of Mathematical Functions......

Pranab Ghosh

2000-06-11T23:59:59.000Z

70

Black Holes in Active Galaxies  

E-Print Network [OSTI]

Recent years have seen tremendous progress in the quest to detect supermassive black holes in the centers of nearby galaxies, and gas-dynamical measurements of the central masses of active galaxies have been valuable contributions to the local black hole census. This review summarizes measurement techniques and results from observations of spatially resolved gas disks in active galaxies, and reverberation mapping of the broad-line regions of Seyfert galaxies and quasars. Future prospects for the study of black hole masses in active galaxies, both locally and at high redshift, are discussed.

A. J. Barth

2003-10-15T23:59:59.000Z

71

Thermodynamics of Lifshitz black holes  

Science Journals Connector (OSTI)

We apply the recently extended conserved Killing charge definition of Abbott-Deser-Tekin formalism to compute, for the first time, the energies of analytic Lifshitz black holes in higher dimensions. We then calculate the temperature and the entropy of this large family of solutions, and study and discuss the first law of black hole thermodynamics. Along the way we also identify the possible critical points of the relevant quadratic curvature gravity theories. Separately, we also apply the generalized Killing charge definition to compute the energy and the angular momentum of the warped AdS3 black hole solution of the three-dimensional new massive gravity theory.

Deniz Olgu Devecio?lu and zgr Sar?o?lu

2011-06-23T23:59:59.000Z

72

Life in a Tree Hole  

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

Tree Hole Tree Hole Nature Bulletin No. 581 November 21, 1959 Forest Preserve District of Cook County Daniel Ryan, President Roberts Mann, Conservation Editor David H Thompson, Senior Naturalist LIFE IN A TREE HOLE A forest is much more than just trees. It includes all of the underbrush, wildflowers and other vegetation that grow beneath these trees; as well as all of its animal life, both large and small. Sunshine, rain, wind, soil, and the leaf litter on the ground are part of it, too. A forest is a community -- a fabric in which the lives of its inhabitants are woven together and into their surroundings by a complex web of interrelations. Tree holes -- together with the birds, mammals and small life which they shelter -- furnish an important binding force in this forest community.

73

Thermodynamics of regular black hole  

E-Print Network [OSTI]

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.

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

2007-08-23T23:59:59.000Z

74

Of the Black Hole Thermodynamics  

E-Print Network [OSTI]

About thirty years ago, Bekenstein and Hawking introduced three basic concepts relating to black hole, namely, the "area entropy", "gravitation temperature" and "thermal radiation". The author analyzes these concepts systematically and concludes that they are mostly inadequate or wrong. He points out that a black hole's taking in thermal radiation from the space is an energy-gathering process. It is special, even extraordinary. It reduces entropy, violating Clausius' second law.

Xinyong Fu

2005-01-11T23:59:59.000Z

75

Lattice Black Holes  

E-Print Network [OSTI]

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.

Steven Corley; Ted Jacobson

1998-03-26T23:59:59.000Z

76

Black hole quantum tunnelling and black hole entropy correction  

E-Print Network [OSTI]

Parikh-Wilczek tunnelling framework, which treats Hawking radiation as a tunnelling process, is investigated again. As the first order correction, the log-corrected entropy-area relation naturally emerges in the tunnelling picture if we consider the emission of a spherical shell. The second order correction of the emission rate for the Schwarzschild black hole is calculated too. In this level, the result is still in agreement with the unitary theory, however, the entropy of the black hole will contain three parts: the usual Bekenstein-Hawking entropy, the logarithmic term and the inverse area term. In our results the coefficient of the logarithmic term is -1. Apart from a coefficient, Our correction to the black hole entropy is consistent with that of loop quantum gravity.

Jingyi Zhang

2008-06-15T23:59:59.000Z

77

Hole in the ozone layer?  

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

Hole in the ozone layer? Hole in the ozone layer? Name: Kelley Location: N/A Country: N/A Date: N/A Question: Is there really a hole in the ozone layer? Replies: That depends on what one means by a "hole". There is a thinning of the layer that is particularly severe during certain seasons at the poles. But the ozone layer is thinning most everywhere. The thinning around the south pole of earth is particularly stunning, and has been referred to as a hole even though some ozone still exists there, it is much less concentrated. As you may know, this ozone destruction is probably due to human release of pollutants such as clorofluorocarbons (CFCs) an due to natural sources such as chemicals from volcanic eruptions. CFCs are used is cooling systems such as refrigerators and air conditioning. There is an international agreement to phase out the use of these destructive chemicals but they won't be banned entirely for years for fears of losing money. Meanwhile the ozone layer thins and we are exposed to increasingly higher doses of cancer causing radiation

78

Energy on black hole spacetimes  

E-Print Network [OSTI]

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.

Alejandro Corichi

2012-07-18T23:59:59.000Z

79

Coherence effects in hole superconductivity  

Science Journals Connector (OSTI)

We discuss the behavior of various observables that depend on matrix elements of operators in the superconducting state within the model of hole superconductivity. In this model, the gap exhibits a linear dependence on the band energy, and the bandwidth depends on the carrier concentration and can become very small for low hole density. We study, in particular, the behavior of ultrasonic attenuation, NMR relaxation rate, and electromagnetic absorption, and present results for parameters expected to be in the range that describes the high-Tc oxides. It is found that the energy dependence of the gap does not give rise to qualitatively different behavior, but significant differences from weak-coupling BCS behavior occur at low hole concentration due to the extreme narrowness of the band.

F. Marsiglio and J. E. Hirsch

1991-12-01T23:59:59.000Z

80

Information loss in black holes  

Science Journals Connector (OSTI)

The question of whether information is lost in black holes is investigated using Euclidean path integrals. The formation and evaporation of black holes is regarded as a scattering problem with all measurements being made at infinity. This seems to be well formulated only in asymptotically AdS spacetimes. The path integral over metrics with trivial topology is unitary and information preserving. On the other hand, the path integral over metrics with nontrivial topologies leads to correlation functions that decay to zero. Thus at late times only the unitary information preserving path integrals over trivial topologies will contribute. Elementary quantum gravity interactions do not lose information or quantum coherence.

S. W. Hawking

2005-10-18T23:59:59.000Z

Note: This page contains sample records for the topic "hydroprobe slim holes" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Black hole binary inspiral and trajectory dominance  

E-Print Network [OSTI]

Gravitational waves emitted during the inspiral, plunge and merger of a black hole binary carry linear momentum. This results in an astrophysically important recoil to the final merged black hole, a kick that can eject ...

Price, Richard H.

82

Black hole Meissner effect and entanglement  

E-Print Network [OSTI]

Extremal black holes tend to expel magnetic and electric fields. Fields are unable to reach the horizon because the length of the black hole throat blows up in the extremal limit. The length of the throat is related to the ...

Penna, Robert

83

Hawking Emission and Black Hole Thermodynamics  

E-Print Network [OSTI]

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

Don N. Page

2006-12-18T23:59:59.000Z

84

Microhole Array | Open Energy Information  

Open Energy Info (EERE)

data using small-diameter downhole tools designed for slim holes. Additional Info CostTime Dependency: Microholes cost less to drill than traditional wellbores, delivering...

85

High precision, rapid laser hole drilling  

DOE Patents [OSTI]

A laser system produces a first laser beam for rapidly removing the bulk of material in an area to form a ragged hole. The laser system produces a second laser beam for accurately cleaning up the ragged hole so that the final hole has dimensions of high precision.

Chang, Jim J.; Friedman, Herbert W.; Comaskey, Brian J.

2013-04-02T23:59:59.000Z

86

Time (hole?) machines John Byron Manchak  

E-Print Network [OSTI]

Time (hole?) machines John Byron Manchak Department of Philosophy, University of Washington, Box machines Hole machines Time travel General relativity a b s t r a c t Within the context of general relativity, we consider a type of "time machine" and introduce the related "hole machine". We review what

Manchak, John

87

Absorption cross section in Lifshitz black hole  

E-Print Network [OSTI]

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.

Taeyoon Moon; Yun Soo Myung

2012-05-10T23:59:59.000Z

88

Signatures of black holes at the LHC  

E-Print Network [OSTI]

Signatures of black hole events at CERN's Large Hadron Collider are discussed. Event simulations are carried out with the Fortran Monte Carlo generator CATFISH. Inelasticity effects, exact field emissivities, color and charge conservation, corrections to semiclassical black hole evaporation, gravitational energy loss at formation and possibility of a black hole remnant are included in the analysis.

Marco Cavaglia; Romulus Godang; Lucien M. Cremaldi; Donald J. Summers

2007-07-02T23:59:59.000Z

89

Supermassive black holes from supermassive stars  

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

Supermassive black holes from supermassive stars Supermassive black holes from supermassive stars 1663 Los Alamos science and technology magazine Latest Issue:November 2013 All Issues » submit Supermassive black holes from supermassive stars Supermassive stars in the early universe gave supermassive black holes a head start March 25, 2013 simulations suggest that star formation conditions back then allowed the first stars to become supermassive themselves In this simulation, a black hole that was just formed by the collapse of a supermassive star is surrounded by a distribution of gas (color indicates density). Because the black hole (located at the center but too small to see) grows by consuming the available gas, simulations like this one help determine how quickly the black hole can grow. The progenitor of this black

90

Accelerating and rotating black holes  

E-Print Network [OSTI]

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.

J. B. Griffiths; J. Podolsky

2005-07-06T23:59:59.000Z

91

Black Holes at the LHC  

E-Print Network [OSTI]

In these two lectures, we will address the topic of the creation of small black holes during particle collisions in a ground-based accelerator, such as LHC, in the context of a higher-dimensional theory. We will cover the main assumptions, criteria and estimates for their creation, and we will discuss their properties after their formation. The most important observable effect associated with their creation is likely to be the emission of Hawking radiation during their evaporation process. After presenting the mathematical formalism for its study, we will review the current results for the emission of particles both on the brane and in the bulk. We will finish with a discussion of the methodology that will be used to study these spectra, and the observable signatures that will help us identify the black-hole events.

Panagiota Kanti

2008-02-15T23:59:59.000Z

92

Down hole periodic seismic generator  

DOE Patents [OSTI]

A down hole periodic seismic generator system for transmitting variable frequency, predominantly shear-wave vibration into earth strata surrounding a borehole. The system comprises a unitary housing operably connected to a well head by support and electrical cabling and contains clamping apparatus for selectively clamping the housing to the walls of the borehole. The system further comprises a variable speed pneumatic oscillator and a self-contained pneumatic reservoir for producing a frequency-swept seismic output over a discrete frequency range.

Hardee, Harry C. (Albuquerque, NM); Hills, Richard G. (Las Cruces, NM); Striker, Richard P. (Albuquerque, NM)

1989-01-01T23:59:59.000Z

93

Primordial black hole minimum mass  

SciTech Connect (OSTI)

In this paper we revisit thermodynamic constraints on primordial black hole (PBH) formation in the early universe. Under the assumption that PBH mass is equal to the cosmological horizon mass, one can use the 2nd Law of Thermodynamics to put a lower limit on the PBH mass. In models of PBH formation, however, PBHs are created at some fraction of the horizon mass. We show that this thermodynamic constraint still holds for subhorizon PBH formation.

Chisholm, James R. [Institute for Fundamental Theory, University of Florida, Gainesville, Florida 32611-8440 (United States)

2006-08-15T23:59:59.000Z

94

Black Hole Thermodynamics and Electromagnetism  

E-Print Network [OSTI]

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.

Burra G. Sidharth

2005-07-15T23:59:59.000Z

95

Quantum Geometry and Black Holes  

E-Print Network [OSTI]

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...

G., J Fernando Barbero

2015-01-01T23:59:59.000Z

96

Entanglement entropy of black holes  

E-Print Network [OSTI]

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.

Sergey N. Solodukhin

2011-04-19T23:59:59.000Z

97

Colorful quantum black holes at the LHC  

E-Print Network [OSTI]

We examine the LHC phenomenology of quantum black holes in models of TeV gravity. By quantum black holes we mean black holes of the smallest masses and entropies, far from the semiclassical regime. These black holes are formed and decay over short distances, and typically carry SU(3) color charges inherited from their parton progenitors. Based on a few minimal assumptions, such as gauge invariance, we identify interesting signatures for quantum black hole decay such as 2 jets, jet + hard photon, jet + missing energy and jet + charged lepton, which should be readily visible above background. The detailed phenomenology depends heavily on whether one requires a Lorentz invariant, low-energy effective field theory description of black hole processes.

Xavier Calmet; Wei Gong; Stephen D. H. Hsu

2008-06-27T23:59:59.000Z

98

Spinning Black Holes as Particle Accelerators  

Science Journals Connector (OSTI)

It has recently been pointed out that particles falling freely from rest at infinity outside a Kerr black hole can in principle collide with an 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 ultraenergetic collisions cannot occur near black holes in nature.

Ted Jacobson and Thomas P. Sotiriou

2010-01-14T23:59:59.000Z

99

Black hole entropy: inside or out?  

E-Print Network [OSTI]

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.

Ted Jacobson; Donald Marolf; Carlo Rovelli

2005-01-14T23:59:59.000Z

100

Interaction of fermions with black holes  

SciTech Connect (OSTI)

Bekenstein and Meisels used statistical thermodynamic arguments to obtain the probability distribution of fermions emitted by a black hole when a fermion is incident. In contrast with Bekenstein and Meisels, we model the black hole as a perfect blackbody surrounded by a mirror. Our probability distribution for emitted fermions agrees with the probability distribution of Bekenstein and Meisels, but the interpretation of how fermions interact with the black hole is different from the interpreteation given by Bekenstein and Meisels.

Jones T.O. III

1986-04-15T23:59:59.000Z

Note: This page contains sample records for the topic "hydroprobe slim holes" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Electromagnetic Beams Overpass the Black Hole Horizon  

E-Print Network [OSTI]

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.

Alexander Burinskii

2008-06-16T23:59:59.000Z

102

Absorption cross section of RN black hole  

E-Print Network [OSTI]

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.

Sini R.; V. C. Kuriakose

2007-08-23T23:59:59.000Z

103

Thermodynamics of dilaton-axion black holes  

SciTech Connect (OSTI)

Considering a generalized action for the Einstein-Maxwell theory in four dimensions coupled to scalar and pseudoscalar fields, the thermodynamic properties of asymptotically flat black hole solutions in such a background are investigated. Bekenstein-Hawking area-entropy law is verified for these class of black holes. From the property of specific heat, it is shown that such black holes can be stable for a certain choice of the parameters like charge, mass, and the scalar vacuum expectation value. The possibility of a black hole phase transition is discussed in this context.

Ghosh, Tanwi; SenGupta, Soumitra [Department of Theoretical Physics, Indian Association for the Cultivation of Science, Jadavpur, Calcutta-700 032 (India)

2008-12-15T23:59:59.000Z

104

Black Holes: from Speculations to Observations  

E-Print Network [OSTI]

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.

Thomas W. Baumgarte

2006-04-13T23:59:59.000Z

105

Locking Information in Black Holes  

Science Journals Connector (OSTI)

We show that a central presumption in the debate over black-hole information loss is incorrect. Ensuring that information not escape during evaporation does not require that it all remain trapped until the final stage of the process. Using the recent quantum information-theoretic result of locking, we show that the amount of information that must remain can be very small, even as the amount already radiated is negligible. Information need not be additive: A small system can lock a large amount of information, making it inaccessible. Only if the set of initial states is restricted can information leak.

John A. Smolin and Jonathan Oppenheim

2006-02-28T23:59:59.000Z

106

Dynamics of oscillating relativistic tori around Kerr black holes  

Science Journals Connector (OSTI)

......angular momentum discs around Schwarzschild black holes, namely that...transmission of the signal recycling mirror (Shoemaker 2004)]. This...angular momentum discs around Schwarzschild black holes were considered...accretion solution on to a Schwarzschild black hole (Michel 1972......

Olindo Zanotti; Jos A. Font; Luciano Rezzolla; Pedro J. Montero

2005-02-01T23:59:59.000Z

107

Black holes cannot support conformal scalar hair  

E-Print Network [OSTI]

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.

T. Zannias

1994-09-14T23:59:59.000Z

108

Category:Thermal Gradient Holes | Open Energy Information  

Open Energy Info (EERE)

in category "Thermal Gradient Holes" This category contains only the following page. T Thermal Gradient Holes Retrieved from "http:en.openei.orgwindex.php?titleCategory:T...

109

T-623: HP Business Availability Center Input Validation Hole...  

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

Business Availability Center Input Validation Hole Permits Cross-Site Scripting Attacks T-623: HP Business Availability Center Input Validation Hole Permits Cross-Site Scripting...

110

Three Hydrogen Bond Donor Catalysts: Oxyanion Hole Mimics and...  

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

Hydrogen Bond Donor Catalysts: Oxyanion Hole Mimics and Transition State Analogues. Three Hydrogen Bond Donor Catalysts: Oxyanion Hole Mimics and Transition State Analogues....

111

Black hole foraging: feedback drives feeding  

E-Print Network [OSTI]

We suggest a new picture of supermassive black hole (SMBH) growth in galaxy centers. Momentum-driven feedback from an accreting hole gives significant orbital energy but little angular momentum to the surrounding gas. Once central accretion drops, the feedback weakens and swept-up gas falls back towards the SMBH on near-parabolic orbits. These intersect near the black hole with partially opposed specific angular momenta, causing further infall and ultimately the formation of a small-scale accretion disk. The feeding rates into the disk typically exceed Eddington by factors of a few, growing the hole on the Salpeter timescale and stimulating further feedback. Natural consequences of this picture include (i) the formation and maintenance of a roughly toroidal distribution of obscuring matter near the hole; (ii) random orientations of successive accretion disk episodes; (iii) the possibility of rapid SMBH growth; (iv) tidal disruption of stars and close binaries formed from infalling gas, resulting in visible fl...

Dehnen, Walter

2013-01-01T23:59:59.000Z

112

Black Hole Superradiance in Dynamical Spacetime  

E-Print Network [OSTI]

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.

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

2014-03-14T23:59:59.000Z

113

Black Hole Evaporation in an Expanding Universe  

E-Print Network [OSTI]

We calculate the quantum radiation power of black holes which are asymptotic to the Einstein-de Sitter universe at spatial and null infinities. We consider two limiting mass accretion scenarios, no accretion and significant accretion. We find that the radiation power strongly depends on not only the asymptotic condition but also the mass accretion scenario. For the no accretion case, we consider the Einstein-Straus solution, where a black hole of constant mass resides in the dust Friedmann universe. We find negative cosmological correction besides the expected redshift factor. This is given in terms of the cubic root of ratio in size of the black hole to the cosmological horizon, so that it is currently of order $10^{-5} (M/10^{6}M_{\\odot})^{1/3} (t/14 {Gyr})^{-1/3}$ but could have been significant at the formation epoch of primordial black holes. Due to the cosmological effects, this black hole has not settled down to an equilibrium state. This cosmological correction may be interpreted in an analogy with the radiation from a moving mirror in a flat spacetime. For the significant accretion case, we consider the Sultana-Dyer solution, where a black hole tends to increase its mass in proportion to the cosmological scale factor. In this model, we find that the radiation power is apparently the same as the Hawking radiation from the Schwarzschild black hole of which mass is that of the growing mass at each moment. Hence, the energy loss rate decreases and tends to vanish as time proceeds. Consequently, the energy loss due to evaporation is insignificant compared to huge mass accretion onto the black hole. Based on this model, we propose a definition of quasi-equilibrium temperature for general conformal stationary black holes.

Hiromi Saida; Tomohiro Harada; Hideki Maeda

2007-05-28T23:59:59.000Z

114

Some remarks on black hole thermodynamics  

E-Print Network [OSTI]

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.

R. Y. Chiao

2010-12-27T23:59:59.000Z

115

Chaotic string-capture by black hole  

Science Journals Connector (OSTI)

We consider a macroscopic charge-current carrying (cosmic) string in the background of a Schwarzschild black hole. The string is taken to be circular and is allowed to oscillate and to propagate in the direction perpendicular to its plane (that is parallel to the equatorial plane of the black hole). Numerical investigations indicate that the system is non-integrable, but the interaction with the gravitational field of the black hole still gives rise to various qualitatively simple processes like `adiabatic capture' and `string transmutation'.

A L Larsen

1994-01-01T23:59:59.000Z

116

Binary Black Hole Accretion Flows From a Misaligned Circumbinary Disk  

Science Journals Connector (OSTI)

......mass-accretion-rate variation per binary...because each black hole passes across the circumbinary...mass-accretion-rate variation per binary...holes|black hole physics|Galaxies: nuclei...because each black hole passes across the circumbinary...the mass accretion rates is also independent......

Kimitake Hayasaki; Hideki Saito; Shin Mineshige

2013-08-25T23:59:59.000Z

117

(1) Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543 USA(1) Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543 USA (2) Harvard Medical School, Boston, MA 02114 USA(2) Harvard Medical School, Boston  

E-Print Network [OSTI]

(1) Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543 USA(1) Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543 USA (2) Harvard Medical School, Boston, MA 02114 USA(2) Harvard Medical School, Boston, MA 02114 USA (3) Section on Auditory Mechanics, NIDCD

118

Thermodynamics of the Schwarzschild-de Sitter black hole: Thermal stability of the Nariai black hole  

SciTech Connect (OSTI)

We study the 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.

Myung, Yun Soo [Institute of Basic Science and School of Computer Aided Science Inje University, Gimhae 621-749 (Korea, Republic of)

2008-05-15T23:59:59.000Z

119

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

E-Print Network [OSTI]

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.

Yun Soo Myung

2007-12-20T23:59:59.000Z

120

Phase transitions and Geometrothermodynamics of Regular black holes  

E-Print Network [OSTI]

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.

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

2014-06-16T23:59:59.000Z

Note: This page contains sample records for the topic "hydroprobe slim holes" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Conserved quantities in a black hole collision  

E-Print Network [OSTI]

The Newman-Penrose constants of the spacetime corresponding to the development of the Brill-Lindquist initial data are calculated by making use of a particular representation of spatial infinity due to H. Friedrich. The Brill-Lindquist initial data set represents the head-on collision of two non-rotating black holes. In this case one non-zero constant is obtained. Its value is given in terms of the product of the individual masses of the black holes and the square of a distance parameter separating the two black holes. This constant retains its value all along null infinity, and therefore it provides information about the late time evolution of the collision process. In particular, it is argued that the magnitude of the constants provides information about the amount of residual radiation contained in the spacetime after the collision of the black holes.

S. Dain; J. A. Valiente-Kroon

2001-05-28T23:59:59.000Z

122

Spectral line broadening in magnetized black holes  

E-Print Network [OSTI]

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

Valeri P. Frolov; Andrey A. Shoom; Christos Tzounis

2014-05-02T23:59:59.000Z

123

Energy of 4-Dimensional Black Hole, etc  

E-Print Network [OSTI]

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.

Dmitriy Palatnik

2011-07-18T23:59:59.000Z

124

Horizon Operator Approach to Black Hole Quantization  

E-Print Network [OSTI]

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\

G. 't Hooft

1994-02-21T23:59:59.000Z

125

Jordan Algebras and Extremal Black Holes  

E-Print Network [OSTI]

We review various properties of the exceptional Euclidean Jordan algebra of degree three. Euclidean Jordan algebras of degree three and their corresponding Freudenthal triple systems were recently shown to be intimately related to extremal black holes in N=2, d=4 homogeneous supergravities. Using a novel type of eigenvalue problem with eigenmatrix solutions, we elucidate the rich matrix geometry underlying the exceptional N=2, d=4 homogeneous supergravity and explore the relations to extremal black holes.

Michael Rios

2007-03-27T23:59:59.000Z

126

Black hole entropy and higher curvature interactions  

Science Journals Connector (OSTI)

A general formula for the entropy of stationary black holes in Lovelock higher-curvature 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.

Ted Jacobson and Robert C. Myers

1993-06-14T23:59:59.000Z

127

Mutiny at the white-hole district  

E-Print Network [OSTI]

The white-hole sector of Kruskal's solution is almost never used in physical applications. However, it might contain the solution to many of the problems associated with gravitational collapse and evaporation. This essay tries to draw attention to some bouncing geometries that make a democratic use of the black- and white-hole sectors. We will argue that these types of behaviour could be perfectly natural in some approaches to the next physical level beyond classical general relativity.

Carlos Barcel; Ral Carballo-Rubio; Luis J. Garay

2014-07-05T23:59:59.000Z

128

Thermodynamics and evaporation of the noncommutative black hole  

E-Print Network [OSTI]

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.

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

2006-11-24T23:59:59.000Z

129

Solar Wind Forecasting with Coronal Holes  

E-Print Network [OSTI]

An empirical model for forecasting solar wind speed related geomagnetic events is presented here. The model is based on the estimated location and size of solar coronal holes. This method differs from models that are based on photospheric magnetograms (e.g., Wang-Sheeley model) to estimate the open field line configuration. Rather than requiring the use of a full magnetic synoptic map, the method presented here can be used to forecast solar wind velocities and magnetic polarity from a single coronal hole image, along with a single magnetic full-disk image. The coronal hole parameters used in this study are estimated with Kitt Peak Vacuum Telescope He I 1083 nm spectrograms and photospheric magnetograms. Solar wind and coronal hole data for the period between May 1992 and September 2003 are investigated. The new model is found to be accurate to within 10% of observed solar wind measurements for its best one-month periods, and it has a linear correlation coefficient of ~0.38 for the full 11 years studied. Using a single estimated coronal hole map, the model can forecast the Earth directed solar wind velocity up to 8.5 days in advance. In addition, this method can be used with any source of coronal hole area and location data.

S. Robbins; C. J. Henney; J. W. Harvey

2007-01-09T23:59:59.000Z

130

Electrical resistance of metallized via?holes  

Science Journals Connector (OSTI)

The resistance of a via?hole laser?drilled through an alumina substrate depends on the hole geometry the type of probe the deposition technique and the properties of the film. If the walls of the hole constitute a truncated cone the resistance is R s/?[ln(d 2/d 1)]{1/4 + [h/(d 2 ? d 1)]2}1/2 where R s is the sheet resistance h is the substrate thickness and d 1 and d 2 are the diameters. Increasing the larger diameter helps by (a) reducing the rim?to?rim resistance (b) reducing the spreading resistance and (c) making the walls more accessible for metallization. A four?point probe on the other hand measures the rim?to?rim resistance as approximately (R s/?) ln cosh (h/d) where d is an average diameter. If the hole is partially bare the four?point reading will depend on probe orientation. A comparison of calculation and measurement indicates R s in the hole to be between two and forty times R s outside depending on the thickness. Electrical probing of broken?open holes showed this to be due to thickness differences not roughness or ledge resistance.

Peter M. Hall

1975-01-01T23:59:59.000Z

131

Initial data for black hole evolutions  

E-Print Network [OSTI]

We discuss the initial value problem of general relativity in its recently unified Lagrangian and Hamiltonian pictures and present a multi-domain pseudo-spectral collocation method to solve the resulting coupled nonlinear partial differential equations. Using this code, we explore several approaches to construct initial data sets containing one or two black holes: We compute quasi-circular orbits for spinning equal mass black holes and unequal mass (nonspinning) black holes using the effective potential method with Bowen-York extrinsic curvature. We compare initial data sets resulting from different decompositions, and from different choices of the conformal metric with each other. Furthermore, we use the quasi-equilibrium method to construct initial data for single black holes and for binary black holes in quasi-circular orbits. We investigate these binary black hole data sets and examine the limits of large mass-ratio and wide separation. Finally, we propose a new method for constructing spacetimes with superposed gravitational waves of possibly very large amplitude.

Harald P. Pfeiffer

2005-10-04T23:59:59.000Z

132

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

E-Print Network [OSTI]

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.

Hal M. Haggard; Carlo Rovelli

2014-07-06T23:59:59.000Z

133

Black Hole Evaporation in an Expanding Universe  

E-Print Network [OSTI]

We calculate the quantum radiation power of black holes which are asymptotic to the Einstein-de Sitter universe at spatial and null infinities. We consider two limiting mass accretion scenarios, no accretion and significant accretion. We find that the radiation power strongly depends on not only the asymptotic condition but also the mass accretion scenario. For the no accretion case, we consider the Einstein-Straus solution, where a black hole of constant mass resides in the dust Friedmann universe. We find negative cosmological correction besides the expected redshift factor. This is given in terms of the cubic root of ratio in size of the black hole to the cosmological horizon, so that it is currently of order $10^{-5} (M/10^{6}M_{\\odot})^{1/3} (t/14 {Gyr})^{-1/3}$ but could have been significant at the formation epoch of primordial black holes. Due to the cosmological effects, this black hole has not settled down to an equilibrium state. This cosmological correction may be interpreted in an analogy with th...

Saida, Hiromi; Maeda, Hideki

2007-01-01T23:59:59.000Z

134

Injection of Electrons and Holes into Nanostructures  

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

Injection of Electrons and Holes into Nanostructures Injection of Electrons and Holes into Nanostructures This program targets fundamental understanding of nanoscale charge transfer processes. The proposed work draws on the strengths of the Brookhaven Chemistry Department in the areas of electron transfer experiment and theory, and extends the area of inquiry to nanoscale processes. Electron/hole injection into a wire, a nanocrystal, a nanotube or other nanostructure in solution may be brought about by light absorption, by an electron pulse (pulse radiolysis, LEAF), by a chemical reagent, or through an electrode. These processes are being studied by transient methods by following conductivity, current, but most generally, spectroscopic changes in the solutions to determine the dynamics of charge injection. The observed transient spectra can also provide values for electron-transfer coupling elements and energetics. Theoretical/computational studies can help in materials design and in the interpretation of the experimental results. The experimental systems being examined include molecular wires and metal nanoclusters.

135

Thermal Gradient Holes | Open Energy Information  

Open Energy Info (EERE)

Thermal Gradient Holes Thermal Gradient Holes Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Thermal Gradient Holes Details Activities (50) Areas (39) Regions (4) NEPA(29) Exploration Technique Information Exploration Group: Drilling Techniques Exploration Sub Group: Exploration Drilling Parent Exploration Technique: Exploration Drilling Information Provided by Technique Lithology: Stratigraphic/Structural: Hydrological: Field wide fluid flow characteristics if an array of wells are drilled Thermal: Mapping and projecting thermal anomalies Cost Information Low-End Estimate (USD): 5.00500 centUSD 0.005 kUSD 5.0e-6 MUSD 5.0e-9 TUSD / foot Median Estimate (USD): 16.501,650 centUSD 0.0165 kUSD 1.65e-5 MUSD 1.65e-8 TUSD / foot High-End Estimate (USD): 50.005,000 centUSD

136

Probing black holes with constellation-X  

Science Journals Connector (OSTI)

Constellation-X is a premiere X-ray spectroscopy mission due to launch within the next decade. With a factor of 100 increase in sensitivity over current X-ray spectroscopy missions and an excellent energy resolution of 2 eV at 6 keV one of the prime science goals of the mission will be to observe activity near the black hole event horizon by measuring changes in the Fe K? fluorescence emission line profile and time-linked intensity changes between the line and the continuum. Detailed variability studies with Constellation-X will allow us to reconstruct images of the accretion disk probe the effects of strong gravity in the vicinity of black holes and measure black hole mass and spin via deconvolution of the line profile.

Kimberly A. Weaver

2001-01-01T23:59:59.000Z

137

Black Hole Complementarity in Gravity's Rainbow  

E-Print Network [OSTI]

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.

Gim, Yongwan

2015-01-01T23:59:59.000Z

138

Nonperturbative black hole entropy and Kloosterman sums  

E-Print Network [OSTI]

Non-perturbative quantum corrections to supersymmetric black hole entropy often involve nontrivial number-theoretic phases called Kloosterman sums. We show how these sums can be obtained naturally from the functional integral of supergravity in asymptotically AdS_2 space for a class of black holes. They are essentially topological in origin and correspond to charge-dependent phases arising from the various gauge and gravitational Chern-Simons terms and boundary Wilson lines evaluated on Dehn-filled solid 2-torus. These corrections are essential to obtain an integer from supergravity in agreement with the quantum degeneracies, and reveal an intriguing connection between topology, number theory, and quantum gravity. We give an assessment of the current understanding of quantum entropy of black holes.

Dabholkar, Atish; Murthy, Sameer

2014-01-01T23:59:59.000Z

139

The AGN Black Hole Mass Database  

E-Print Network [OSTI]

The AGN Black Hole Mass Database is a compilation of all published spectroscopic reverberation-mapping studies of active galaxies. We have created a public web interface, where users may get the most up-to-date black hole masses from reverberation mapping for any particular active galactic nucleus (AGN), as well as obtain the individual measurements upon which the masses are based and the appropriate references. While the database currently focuses on the measurements necessary for black hole mass determinations, we also plan to expand it in the future to include additional useful information, such as host-galaxy characteristics. New reverberation mapping results will also be incorporated into the database as they are published in peer-refereed journals.

Bentz, Misty C

2014-01-01T23:59:59.000Z

140

Black hole chromosphere at the CERN LHC  

Science Journals Connector (OSTI)

If the scale of quantum gravity is near a TeV, black holes will be copiously produced at the CERN 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.

Luis Anchordoqui and Haim Goldberg

2003-03-26T23:59:59.000Z

Note: This page contains sample records for the topic "hydroprobe slim holes" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Extremal limits and black hole entropy  

E-Print Network [OSTI]

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.

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

2009-01-08T23:59:59.000Z

142

Strings as solitons & black holes as strings  

Science Journals Connector (OSTI)

Supersymmetric closed string theories contain an infinite tower of BPS-saturated, oscillating, macroscopic strings in the perturbative spectrum. When these theories have dual formulations, this tower of states must exist nonperturbatively as solitons in the dual theories. We present a general class of exact solutions of low-energy supergravity that corresponds to all these states. After dimensional reduction they can be interpreted as supersymmetric black holes with a degeneracy related to the degeneracy of the string states. For example, in four dimensions we obtain a point-like solution which is asymptotic to a stationary, rotating, electrically-charged black hole with Regge-bounded angular momentum and with the usual ring-singularity replaced by a string source. This further supports the idea that the entropy of supersymmetric black holes can be understood in terms of counting of string states. We also discuss some applications of these solutions to string duality.

Atish Dabholkar; Jerome P. Gauntlett; Jeffrey A. Harvey; Daniel Waldram

1996-01-01T23:59:59.000Z

143

A Comparison of Intermediate Mass Black Hole Candidate ULXs and Stellar-Mass Black Holes  

E-Print Network [OSTI]

Cool thermal emission components have recently been revealed in the X-ray spectra of a small number of ultra-luminous X-ray (ULX) sources with L_X > 1 E+40 erg/s in nearby galaxies. These components can be well fitted with accretion disk models, with temperatures approximately 5-10 times lower than disk temperatures measured in stellar-mass Galactic black holes when observed in their brightest states. Because disk temperature is expected to fall with increasing black hole mass, and because the X-ray luminosity of these sources exceeds the Eddington limit for 10 Msun black holes (L_Edd = 1.3 E+39 erg/s), these sources are extremely promising intermediate-mass black hole candidates (IMBHCs). In this Letter, we directly compare the inferred disk temperatures and luminosities of these ULXs, with the disk temperatures and luminosities of a number of Galactic black holes. The sample of stellar-mass black holes was selected to include different orbital periods, companion types, inclinations, and column densities. These ULXs and stellar-mass black holes occupy distinct regions of a L_X -- kT diagram, suggesting these ULXs may harbor IMBHs. We briefly discuss the important strengths and weaknesses of this interpretation.

J. M. Miller; A. C. Fabian; M. C. Miller

2004-06-29T23:59:59.000Z

144

How red is a quantum black hole?  

E-Print Network [OSTI]

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.

Viqar Husain; Oliver Winkler

2005-05-30T23:59:59.000Z

145

The effects of fastener hole defects  

E-Print Network [OSTI]

) August 1991 ABSTRACT The Effects of Fastener Hole Defects. (August 1991) Scot D. Andrews, B. S. , Texas A8rM University Chair of Advisory Committee: Dr. Orden O. Ochoa The influence of drilling-induced defects, such as delamination, on the fatigue... Of Delaminated Zone Elements . . Figure 34. Enlarged View Of Area Near Hole 58 59 61 Page Figure 35. Example Finite Element Mesh Figure 36. Selected Elements For Stress Distribution Graphs . . Figure 37. Example Of o? Stress Distribution For 18 Ply Tape...

Andrews, Scot D.

2012-06-07T23:59:59.000Z

146

CHARYBDIS: A Black Hole Event Generator  

E-Print Network [OSTI]

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.

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

2003-07-24T23:59:59.000Z

147

BLACK HOLE ENTROPY IN HIGHER CURVATURE GRAVITY  

E-Print Network [OSTI]

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.

TED JACOBSON; GUNGWON KANG; ROBERT C. MYERS

1995-02-27T23:59:59.000Z

148

Quasilocal first law for black hole thermodynamics  

Science Journals Connector (OSTI)

We first show that stationary black holes satisfy an extremely simple quasilocal form of the first law, ?E=?8??A, where the (quasilocal) energy E=A/(8??) and (local) surface gravity ?=1/?, with A the horizon area and ? is a proper length characterizing the distance to the horizon of a preferred family of quasilocal observers suitable for thermodynamical considerations. Our construction is extended to the more general framework of isolated horizons. The local surface gravity is universal. This has important implications for semiclassical considerations of black hole physics as well as for the fundamental quantum description arising in the context of loop quantum gravity.

Ernesto Frodden; Amit Ghosh; Alejandro Perez

2013-06-24T23:59:59.000Z

149

Steady and unsteady calibration of multi-hole probes  

E-Print Network [OSTI]

This thesis presents the development of a data crographics. reduction algorithm for multi-hole pressure probes. The algorithm has been developed for the reduction of calibration data from miniature non-nulling multi-hole probes in compressible...

Johansen, Espen S

1998-01-01T23:59:59.000Z

150

What is the topology of a Schwarzschild black hole?  

E-Print Network [OSTI]

We investigate the topology of Schwarzschild's black hole through the immersion of this space-time in spaces of higher dimension. Through the immersions of Kasner and Fronsdal we calculate the extension of the Schwarzschild's black hole.

Edmundo M. Monte

2011-11-24T23:59:59.000Z

151

Chapter 3 Topology and Uniqueness of Higher Dimensional Black Holes  

Science Journals Connector (OSTI)

......of Particle and Nuclear Studies, High Energy Accelerator Research Organization...asymptotically flat vacuum black holes in...of Particle and Nuclear Studies, High Energy Accelerator Research Organization...asymptotically flat vacuum black holes in......

Daisuke Ida; Akihiro Ishibashi; Tetsuya Shiromizu

2011-06-01T23:59:59.000Z

152

Thought Experiment to resolve the Black Hole Information Paradox  

E-Print Network [OSTI]

We propose a combination of two mechanisms that can resolve the black hole information paradox. The first process is that the black hole shrinks by a first order transition, since we assume the entropy is discontinuous. The black hole disappears. The second type of processes conserves unitarity. We assume that within the black hole micro-reversible quantum mechanical processes take place. These are ordinary particle processes, e.g. the decay of an electron and a positron into two photons.

Kay zum Felde

2014-07-22T23:59:59.000Z

153

Particles and scalar waves in noncommutative charged black hole spacetime  

E-Print Network [OSTI]

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.

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

2015-01-01T23:59:59.000Z

154

The third law of thermodynamics for Kerr black holes  

Science Journals Connector (OSTI)

......research-article Articles The third law of thermodynamics for Kerr black holes Isao...condition under which the third law of black-hole thermodynamics for Kerr holes is not violated...diverge to infinity as a power law for , and therefore no Kerr......

Isao Okamoto; Osamu Kaburaki

1991-05-15T23:59:59.000Z

155

Geodesic study of a charged black hole  

E-Print Network [OSTI]

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.

Mehedi Kalam; Nur Farhad; Sk. Monowar Hossein

2013-03-17T23:59:59.000Z

156

Black Holes and Sub-millimeter Dimensions  

E-Print Network [OSTI]

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...

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

1998-01-01T23:59:59.000Z

157

Retarded cores, black holes and galaxy formation  

Science Journals Connector (OSTI)

... It seems likely that elliptical galaxies contain massive 'black holes'?objects collapsed within their Schwarzschild radii?in their nuclei (see, for example, Wolfe and Burbidge2). The principal ... seems to be required to power the observed phenomena. For such a mass, the Schwarzschild radius (R s) is about 10?4 pc; for a mass of 1011 ...

John Gribbin

1974-12-06T23:59:59.000Z

158

Schwarzschild black hole in dark energy background  

E-Print Network [OSTI]

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.

Ngangbam Ishwarchandra; Ng. Ibohal; K. Yugindro Singh

2014-09-27T23:59:59.000Z

159

Supermassive Black Hole Binaries: The Search Continues  

E-Print Network [OSTI]

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.

Tamara Bogdanovic

2014-06-19T23:59:59.000Z

160

Chapter 8 Black Holes in Braneworld Models  

Science Journals Connector (OSTI)

......to the four-dimensional Schwarzschild solution, there is no room...deformed from an ordinary Schwarzschild black hole and the radiation...gravitational attraction from its mirror image on the other side of...The attraction from the mirror image will not be larger than......

Norihiro Tanahashi; Takahiro Tanaka

2011-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "hydroprobe slim holes" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

SS433a massive black hole?  

Science Journals Connector (OSTI)

... thin ring in a circular orbit at radius R = r GM/c2 around a Schwarzschild black hole of mass M, the two emission peaks will be at wavelengths given ... we would expect the profiles of the emission peaks at any given time to be mirror images of each other (at least on timescales longer than the orbital time). ...

R. J. TERLEVICH; J. E. PRINGLE

1979-04-19T23:59:59.000Z

162

Black Holes in 4 Nearby Radio Galaxies  

E-Print Network [OSTI]

We study the velocity dispersion profiles of the nuclei of NGC 1326, 2685, 5273 and 5838 in the CO first overtone band. There is evidence for a black hole (BH) in NGC 1326 and 5838. Gas is seen flowing out of the nuclear region of NGC 5273. We put upper limits on the nuclear BHs responsible for its activity and that of NGC 2685.

Mould, Jeremy; Cotter, Garret; Batt, David; Durre', Mark

2014-01-01T23:59:59.000Z

163

Remote down-hole well telemetry  

DOE Patents [OSTI]

The present invention includes an apparatus and method for telemetry communication with oil-well monitoring and recording instruments located in the vicinity of the bottom of gas or oil recovery pipes. Such instruments are currently monitored using electrical cabling that is inserted into the pipes; cabling has a short life in this environment, and requires periodic replacement with the concomitant, costly shutdown of the well. Modulated reflectance, a wireless communication method that does not require signal transmission power from the telemetry package will provide a long-lived and reliable way to monitor down-hole conditions. Normal wireless technology is not practical since batteries and capacitors have to frequently be replaced or recharged, again with the well being removed from service. RF energy generated above ground can also be received, converted and stored down-hole without the use of wires, for actuating down-hole valves, as one example. Although modulated reflectance reduces or eliminates the loss of energy at the sensor package because energy is not consumed, during the transmission process, additional stored extra energy down-hole is needed.

Briles, Scott D. (Los Alamos, NM); Neagley, Daniel L. (Albuquerque, NM); Coates, Don M. (Santa Fe, NM); Freund, Samuel M. (Los Alamos, NM)

2004-07-20T23:59:59.000Z

164

Geodesics and Geodesic Deviation in static Charged Black Holes  

E-Print Network [OSTI]

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.

Ragab M. Gad

2010-03-03T23:59:59.000Z

165

Laser stabilization using spectral hole burning  

E-Print Network [OSTI]

We have frequency stabilized a Coherent CR699-21 dye laser to a transient spectral hole on the 606 nm transition in Pr^{+3}:Y_2SiO_5. A frequency stability of 1 kHz has been obtained on the 10 microsecond timescale together with a long-term frequency drift below 1 kHz/s. RF magnetic fields are used to repopulate the hyperfine levels allowing us to control the dynamics of the spectral hole. A detailed theory of the atomic response to laser frequency errors has been developed which allows us to design and optimize the laser stabilization feedback loop, and specifically we give a stability criterion that must be fulfilled in order to obtain very low drift rates. The laser stability is sufficient for performing quantum gate experiments in Pr^{+3}:Y_2SiO_5.

L. Rippe; B. Julsgaard; A. Walther; S. Krll

2006-11-05T23:59:59.000Z

166

Geometric description of BTZ black holes thermodynamics  

E-Print Network [OSTI]

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.

Hernando Quevedo; Alberto Sanchez

2008-11-15T23:59:59.000Z

167

Hybrid black-hole binary initial data  

E-Print Network [OSTI]

Traditional black-hole binary puncture initial data is conformally flat. This unphysical assumption is coupled with a lack of radiation signature from the binary's past life. As a result, waveforms extracted from evolutions of this data display an abrupt jump. In Kelly et al. [Class.Quant.Grav.27:114005,2010], a new binary black-hole initial data with radiation contents derived in the post-Newtonian (PN) calculation was adapted to puncture evolutions in numerical relativity. This data satisfies the constraint equations to the 2.5PN order, and contains a transverse-traceless "wavy" metric contribution, violating the standard assumption of conformal flatness. Although the evolution contained less spurious radiation, there were undesired features; the unphysical horizon mass loss and the large initial orbital eccentricity. Introducing a hybrid approach to the initial data evaluation, we significantly reduce these undesired features.

Bruno C. Mundim; Bernard J. Kelly; Yosef Zlochower; Hiroyuki Nakano; Manuela Campanelli

2010-12-04T23:59:59.000Z

168

The high energy emission from black holes  

E-Print Network [OSTI]

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.

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

2007-11-06T23:59:59.000Z

169

Black hole remnants in the early universe  

Science Journals Connector (OSTI)

We consider the production of primordial micro black holes (MBH) remnants in the early Universe. These objects induce the Universe to be in a matter-dominated era before the onset of inflation. Effects of such an epoch on the CMB power spectrum are discussed and computed both analytically and numerically. By comparison with the latest observational data from the WMAP collaboration, we find that our model appears to explain the quadrupole anomaly of the CMB power spectrum.

Fabio Scardigli; Christine Gruber; Pisin Chen

2011-03-09T23:59:59.000Z

170

Hole cleaning requirements with seabed returns  

E-Print Network [OSTI]

size and fluid density. The least important were rotary speed, feed concentration, annulus size, and drillpipe eccentricity. They also reported that, in Newtonian fluids, transport efficiency improves with increasing viscosity; however, they noted... is set; therefore, no marine riser can be utilized. The coring occurs up to 3000 ft below the seafloor with the bit cutting an 11. 438 in. hole. The rig pumps have a maximum output of 600 gpm under normal coring operations with untreated seawater...

Nordt, David Paul

1988-01-01T23:59:59.000Z

171

Comparing quantum black holes and naked singularities  

E-Print Network [OSTI]

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.

T. P. Singh

2000-12-21T23:59:59.000Z

172

Electromagnetic wave scattering by Schwarzschild black holes  

E-Print Network [OSTI]

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.

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

2009-05-20T23:59:59.000Z

173

Spectral hole burning for stopping light  

SciTech Connect (OSTI)

We propose a protocol for storage and retrieval of photon wave packets in a {lambda}-type atomic medium. This protocol derives from spectral hole burning and takes advantages of the specific properties of solid-state systems at low temperature, such as rare-earth ion-doped crystals. The signal pulse is tuned to the center of the hole that has been burnt previously within the inhomogeneously broadened absorption band. The group velocity is strongly reduced, being proportional to the hole width. This way the optically carried information and energy are carried over to the off-resonance optical dipoles. Storage and retrieval are performed by conversion to and from ground-state Raman coherence by using brief {pi} pulses. The protocol exhibits some resemblance with the well-known electromagnetically induced transparency process. It also presents distinctive features such as the absence of coupling beam. In this paper we detail the various steps of the protocol, summarize the critical parameters, and theoretically examine the recovery efficiency.

Lauro, R.; Chaneliere, T.; Le Goueet, J.-L. [Laboratoire Aime Cotton, CNRS UPR3321, Universite Paris Sud, Batiment 505, Campus Universitaire, 91405 Orsay (France)

2009-05-15T23:59:59.000Z

174

Light Loop Echoes and Blinking Black Holes  

E-Print Network [OSTI]

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

175

Dark jets in solar coronal holes  

E-Print Network [OSTI]

A new solar feature termed a dark jet is identified from observations of an extended solar coronal hole that was continuously monitored for over 44 hours by the EUV Imaging Spectrometer on board the Hinode spacecraft in 2011 February 8-10. Line-of-sight velocity maps derived from the coronal Fe XII $\\lambda$195.12 emission line, formed at 1.5 MK, revealed a number of large-scale, jet-like structures that showed significant blueshifts. The structures had either weak or no intensity signal in 193 A filter images from the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory, suggesting that the jets are essentially invisible to imaging instruments. The dark jets are rooted in bright points and occur both within the coronal hole and at the quiet Sun-coronal hole boundary. They exhibit a wide range of shapes, from narrow columns to fan-shaped structures, and sometimes multiple jets are seen close together. A detailed study of one dark jet showed line-of-sight speeds increasing along the jet axis fr...

Young, Peter R

2015-01-01T23:59:59.000Z

176

Quantization of rotating linear dilaton black holes  

E-Print Network [OSTI]

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.

I. Sakalli

2014-06-19T23:59:59.000Z

177

K-Shell-Hole Production, Multiple-Hole Production, Charge-Transfer, and Antisymmetry  

E-Print Network [OSTI]

-shell electron can occur. For example, after making a K-shell hole an L-shell electron may be knocked into it, or an L-shell vacancy may be produced and the K-shell electron promoted to that vacancy in the "Fermi sea" of the target-atom orbitals, In 1973 a.... If one is working in first-order pertur- bation theory E-shell-hole production is correctly obtained by calculating the process for the K elec- tron to be lifted above the "Fermi sea" of occupied target orbitals, i.e., the other electrons play a...

Reading, John F.; Ford, A. Lewis.

1980-01-01T23:59:59.000Z

178

Mineral Test Hole Regulatory Act (Tennessee) | Department of Energy  

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

Mineral Test Hole Regulatory Act (Tennessee) Mineral Test Hole Regulatory Act (Tennessee) Mineral Test Hole Regulatory Act (Tennessee) < Back Eligibility Commercial Construction Developer Fuel Distributor Industrial Installer/Contractor Investor-Owned Utility Municipal/Public Utility Utility Program Info State Tennessee Program Type Environmental Regulations Siting and Permitting Provider Tennessee Department Of Environment and Conservation The Mineral Hole Regulatory Act is applicable to any person (individual, corporation, company, association, joint venture, partnership, receiver, trustee, guardian, executor, administrator, personal representative or private organization of any kind) who wishes to drill a mineral test hole (any hole in excess of one hundred (100) feet drilled during the exploration for minerals but shall exclude auger drilling in surficial or

179

Video: Part of the 'Hole' Story (of Uranium Hexafluoride Cylinders)  

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

Hole Story Hole Story Part of the "Hole" Story (of Uranium Hexafluoride Cylinders) Holes in the depleted Uranium Hexafluoride storage cylinders are investigated. It is shown that corrosion products cause the openings to be self-healing. View this Video in Real Player format Download free RealPlayer SP Highlights of the Video: Video 00:00 Part of the 'Hole' Story Video 00:05 One of the depleted UF6 cylinder storage lots at Portsmouth Video 00:28 48G cylinders, each containing 14 tons of depleted UF6, in storage Video 00:52 Stacked 48G cylinders Video 01:35 UF6 sealed in glass tube Video 02:01 A lifting lug of one cylinder damaging a neighboring cylinder Video 02:37 Damage to small hole cylinder from impact with a lifting lub of an adjoining cylinder

180

Articles which include chevron film cooling holes, and related processes  

DOE Patents [OSTI]

An article is described, including an inner surface which can be exposed to a first fluid; an inlet; and an outer surface spaced from the inner surface, which can be exposed to a hotter second fluid. The article further includes at least one row or other pattern of passage holes. Each passage hole includes an inlet bore extending through the substrate from the inlet at the inner surface to a passage hole-exit proximate to the outer surface, with the inlet bore terminating in a chevron outlet adjacent the hole-exit. The chevron outlet includes a pair of wing troughs having a common surface region between them. The common surface region includes a valley which is adjacent the hole-exit; and a plateau adjacent the valley. The article can be an airfoil. Related methods for preparing the passage holes are also described.

Bunker, Ronald Scott; Lacy, Benjamin Paul

2014-12-09T23:59:59.000Z

Note: This page contains sample records for the topic "hydroprobe slim holes" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Method and apparatus of assessing down-hole drilling conditions  

DOE Patents [OSTI]

A method and apparatus for use in assessing down-hole drilling conditions are disclosed. The apparatus includes a drill string, a plurality of sensors, a computing device, and a down-hole network. The sensors are distributed along the length of the drill string and are capable of sensing localized down-hole conditions while drilling. The computing device is coupled to at least one sensor of the plurality of sensors. The data is transmitted from the sensors to the computing device over the down-hole network. The computing device analyzes data output by the sensors and representative of the sensed localized conditions to assess the down-hole drilling conditions. The method includes sensing localized drilling conditions at a plurality of points distributed along the length of a drill string during drilling operations; transmitting data representative of the sensed localized conditions to a predetermined location; and analyzing the transmitted data to assess the down-hole drilling conditions.

Hall, David R. (Provo, UT); Pixton, David S. (Lehl, UT); Johnson, Monte L. (Orem, UT); Bartholomew, David B. (Springville, UT); Fox, Joe (Spanish Fork, UT)

2007-04-24T23:59:59.000Z

182

Hole Self-Energy Corrections in the Brueckner Theory  

Science Journals Connector (OSTI)

To study corrections to hole propagators in Brueckner theory, an extension of the Hugenholtz convolution theorem is proved. An integral equation is derived for a class of Brueckner hole corrections and approximate solutions are obtained, one of which gives the usual prescription that makes holes propagate on the energy shell. The derivation shows which class of diagrams are included in this prescription and suggests that a more accurate treatment might be needed.

J. Nuttall

1966-09-23T23:59:59.000Z

183

A toroidal black hole for the AGN phenomenon  

E-Print Network [OSTI]

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.

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

2000-08-30T23:59:59.000Z

184

A Quantum Material Model of Static Schwarzschild Black Holes  

E-Print Network [OSTI]

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.

S. -T. Sung

1997-03-16T23:59:59.000Z

185

On the Stability of Black Holes at the LHC  

E-Print Network [OSTI]

The eventual production of mini black holes by proton-proton collisions at the LHC is predicted by theories with large extra dimensions resolvable at the Tev scale of energies. It is expected that these black holes evaporate shortly after its production as a consequence of the Hawking radiation. We show that for theories based on the ADS/CFT correspondence, the produced black holes may have an unstable horizon, which grows proportionally to the square of the distance to the collision point.

M. D. Maia; E. M. Monte

2008-08-19T23:59:59.000Z

186

Temperature, heat flow maps and temperature gradient holes |...  

Open Energy Info (EERE)

Temperature, heat flow maps and temperature gradient holes Author T. G. Zacharakis Organization Colorado Geological Survey in Cooperation with the U.S. Department of Energy...

187

Thermal Gradient Holes At Long Valley Caldera Geothermal Area...  

Open Energy Info (EERE)

Date 1978 - 1985 Usefulness useful DOE-funding Unknown Exploration Basis Thermal gradient drilling also continued during this period, consisting of several holes including: The...

188

Hydrodynamic model for electron-hole plasma in graphene  

E-Print Network [OSTI]

We propose a hydrodynamic model describing steady-state and dynamic electron and hole transport properties of graphene structures which accounts for the features of the electron and hole spectra. It is intended for electron-hole plasma in graphene characterized by high rate of intercarrier scattering compared to external scattering (on phonons and impurities), i.e., for intrinsic or optically pumped (bipolar plasma), and gated graphene (virtually monopolar plasma). We demonstrate that the effect of strong interaction of electrons and holes on their transport can be treated as a viscous friction between the electron and hole components. We apply the developed model for the calculations of the graphene dc conductivity, in particular, the effect of mutual drag of electrons and holes is described. The spectra and damping of collective excitations in graphene in the bipolar and monopolar limits are found. It is shown that at high gate voltages and, hence, at high electron and low hole densities (or vice-versa), the excitations are associated with the self-consistent electric field and the hydrodynamic pressure (plasma waves). In intrinsic and optically pumped graphene, the waves constitute quasineutral perturbations of the electron and hole densities (electron-hole sound waves) with the velocity being dependent only on the fundamental graphene constants.

D. Svintsov; V. Vyurkov; S. Yurchenko; T. Otsuji; V. Ryzhii

2012-01-03T23:59:59.000Z

189

Core Holes At Blue Mountain Geothermal Area (Fairbank & Niggemann...  

Open Energy Info (EERE)

Exploration Activity Details Location Blue Mountain Geothermal Area Exploration Technique Core Holes Activity Date 2002 - 2004 Usefulness useful DOE-funding Unknown Exploration...

190

Black Holes as Conformal Field Theories on Horizons  

E-Print Network [OSTI]

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.

Halyo, Edi

2015-01-01T23:59:59.000Z

191

Thermal Gradient Holes At Chena Geothermal Area (EERE, 2010)...  

Open Energy Info (EERE)

EERE, 2010) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Thermal Gradient Holes At Chena Geothermal Area (EERE, 2010) Exploration Activity...

192

Comparison of Black Hole Generators for the LHC  

E-Print Network [OSTI]

We compare Monte Carlo event generators dedicated to simulating the production and decay of extra-dimensional black holes at the Large Hadron Collider.

Douglas M. Gingrich

2006-10-17T23:59:59.000Z

193

Primordial Black Hole Evolution in Tensor-Scalar Cosmology  

Science Journals Connector (OSTI)

A perturbative analysis shows that black holes do not remember the value of the scalar field ? at the time they formed if ? changes in tensor-scalar cosmology. Moreover, even when the black hole mass in the Einstein frame is approximately unaffected by the changing of ?, 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.

Ted Jacobson

1999-10-04T23:59:59.000Z

194

A rotating black hole in the Galactic Center  

E-Print Network [OSTI]

Recent observations of Sgr A* give strong constraints for possible models of the physical nature of Sgr A* and suggest the presence of a massive black~hole with M0.9) accreting 10^-8.5 - 10^-7 M_sun/yr at a black~hole mass of M=2 10^6 M_sunseen almost edge on. A low mass black hole of M' together with simple scaling laws to provide an easy-to-handle test for the black hole model.

Heino Falcke; Peter L. Biermann; Wolfgang J. Duschl; Peter G. Mezger

1992-12-07T23:59:59.000Z

195

Hole doping in high temperature superconductors using the XANES technique  

E-Print Network [OSTI]

Hole doping in high temperature superconductors using the1994 Thallium-Based High Temperature Superconductors ed A M1994 Thallium-Based High Temperature Superconductors ed A M

Hamdan, Nasser

2012-01-01T23:59:59.000Z

196

Core Holes At Long Valley Caldera Geothermal Area (Eichelberger...  

Open Energy Info (EERE)

Eichelberger, Et Al., 1988) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Core Holes At Long Valley Caldera Geothermal Area (Eichelberger, Et...

197

Core Holes At Steamboat Springs Area (Warpinski, Et Al., 2004...  

Open Energy Info (EERE)

Steamboat Springs Area (Warpinski, Et Al., 2004) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Core Holes At Steamboat Springs Area (Warpinski,...

198

Thermal Gradient Holes At Cove Fort Area - Vapor (Warpinski,...  

Open Energy Info (EERE)

Warpinski, Et Al., 2004) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Thermal Gradient Holes At Cove Fort Area - Vapor (Warpinski, Et Al.,...

199

Core Holes At Long Valley Caldera Geothermal Area (Urban, Et...  

Open Energy Info (EERE)

Urban, Et Al., 1987) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Core Holes At Long Valley Caldera Geothermal Area (Urban, Et Al., 1987)...

200

Thermal Gradient Holes At Chena Geothermal Area (Erkan, Et Al...  

Open Energy Info (EERE)

Erkan, Et Al., 2007) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Thermal Gradient Holes At Chena Geothermal Area (Erkan, Et Al., 2007)...

Note: This page contains sample records for the topic "hydroprobe slim holes" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Thermal Gradient Holes At Obsidian Cliff Area (Hulen, Et Al....  

Open Energy Info (EERE)

Obsidian Cliff Area (Hulen, Et Al., 2003) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Thermal Gradient Holes At Obsidian Cliff Area (Hulen,...

202

Using the Uncharged Kerr Black Hole as a Gravitational Mirror  

Science Journals Connector (OSTI)

We extend the study of the possible use of the Schwarzschild black hole as a gravitational mirror to the more general case of an...

Claes R. Cramer

1997-04-01T23:59:59.000Z

203

The first law of thermodynamics in Lifshitz black holes revisited  

E-Print Network [OSTI]

We obtain the mass expression of the three- and five-dimensional Lifshitz black holes by em- ploying the recently proposed quasilocal formulation of conserved charges, which is based on the off-shell extension of the ADT formalism. Our result is consistent with the first law of black hole thermodynamics and resolves the reported discrepancy between the ADT formalism and the other conventional methods. The same mass expression of Lifshitz black holes is obtained by using an- other quasilocal method by Padmanabhan. We also discuss the reported discrepancy in the context of the extended first law of black hole thermodynamics by allowing the pressure term.

Yongwan Gim; Wontae Kim; Sang-Heon Yi

2014-03-19T23:59:59.000Z

204

Absorption of scalars by extremal black holes in string theory  

E-Print Network [OSTI]

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.

Filipe Moura

2014-06-13T23:59:59.000Z

205

Core Holes At Valles Caldera - Redondo Geothermal Area (Goff...  

Open Energy Info (EERE)

understand the stratigraphy, structure, hydrothermal alteration, and subsurface architecture of the Valles caldera. Several authors have reported results from these core holes,...

206

Core Holes At Valles Caldera - Sulphur Springs Geothermal Area...  

Open Energy Info (EERE)

understand the stratigraphy, structure, hydrothermal alteration, and subsurface architecture of the Valles caldera. Several authors have reported results from these core holes,...

207

Thermal Gradient Holes At Glass Mountain Area (Cumming And Mackie...  

Open Energy Info (EERE)

Area (Cumming And Mackie, 2007) Exploration Activity Details Location Glass Mountain Geothermal Area Exploration Technique Thermal Gradient Holes Activity Date Usefulness not...

208

Location Of Hole And Electron Traps On Nanocrystalline Anatase...  

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

to two overlapping distributions: hole trap emission associated with oxygen vacancies on (101) exposed surfaces, which peaks in the green, and a broader emission...

209

Thermal Gradient Holes At Breitenbush Hot Springs Area (Ingebritsen...  

Open Energy Info (EERE)

(1993) Heat Flow From Four New Research Drill Holes In The Western Cascades, Oregon, Usa Additional References Retrieved from "http:en.openei.orgwindex.php?titleThermalGr...

210

Extremal charged rotating dilaton black holes in odd dimensions  

SciTech Connect (OSTI)

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.

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

211

Extremal Charged Rotating Dilaton Black Holes in Odd Dimensions  

E-Print Network [OSTI]

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.

Masoud Allahverdizadeh; Jutta Kunz; Francisco Navarro-Lerida

2010-07-24T23:59:59.000Z

212

ACCRETION-JET CONNECTION IN BLACK HOLES THE ORIGIN OF STELLAR BLACK HOLES &  

E-Print Network [OSTI]

a very large kinetic energy...Moon @ >.9c" #12;POWERFUL DARK JETS FROM BLACK HOLES Radio (Dubner et al erg/sec · NON RADIATIVE JETS = "DARK" JETS · >50% OF THE ENERGY IS NOT RADIATED 1o = 60 pc1arcsec VLA Since their discovery there have been seven International workshops Compact binaries with jets #12

Maryland at College Park, University of

213

Geodesic Study of Regular Hayward Black Hole  

E-Print Network [OSTI]

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.

G. Abbas; U. Sabiullah

2014-06-03T23:59:59.000Z

214

CHARYBDIS: A Black hole event generator.  

E-Print Network [OSTI]

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...

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

215

Conformal Invariance of Black Hole Temperature  

E-Print Network [OSTI]

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.

Ted Jacobson; Gungwon Kang

1993-07-06T23:59:59.000Z

216

Down-hole periodic seismic generator  

DOE Patents [OSTI]

A down hole periodic seismic generator system is disclosed for transmitting variable frequency, predominantly shear-wave vibration into earth strata surrounding a borehole. The system comprises a unitary housing operably connected to a well head by support and electrical cabling and contains clamping apparatus for selectively clamping the housing to the walls of the borehole. The system further comprises a variable speed pneumatic oscillator and a self-contained pneumatic reservoir for producing a frequency-swept seismic output over a discrete frequency range.

Hardee, H.C.; Hills, R.G.; Striker, R.P.

1982-10-28T23:59:59.000Z

217

Black Hole Constraints on Varying Fundamental Constants  

SciTech Connect (OSTI)

We apply the generalized second law of thermodynamics and derive upper limits on the variation in the fundamental constants. The maximum variation in the electronic charge permitted for black holes accreting and emitting in the present cosmic microwave background corresponds to a variation in the fine-structure constant of {delta}{alpha}/{alpha}{approx_equal}2x10{sup -23} per second. This value matches the variation measured by Webb et al. [Phys. Rev. Lett. 82, 884 (1999); Phys. Rev. Lett. 87, 091301 (2001)] using absorption lines in the spectra of distant quasars and suggests the variation mechanism may be a coupling between the electron and the cosmic photon background.

MacGibbon, Jane H. [Department of Physics and Chemistry, University of North Florida, Jacksonville, Florida 32224 (United States)

2007-08-10T23:59:59.000Z

218

The Fourth Law of Black Hole Thermodynamics  

E-Print Network [OSTI]

We show that black holes fulfill the scaling laws arising in critical transitions. In particular, we find that in the transition from negative to positive values the heat capacities $C_{JQ}$, $C_{\\Omega Q}$ and $C_{J\\Phi}$ give rise to critical exponents satisfying the scaling laws. The three transitions have the same critical exponents as predicted by the universality Hypothesis. We also briefly discuss the implications of this result with regards to the connections among gravitation, quantum mechanics and statistical physics.

C. O. Lousto

1993-06-10T23:59:59.000Z

219

Black Hole Remnants at the LHC  

E-Print Network [OSTI]

We investigate possible signatures of black hole events at the LHC in the hypothesis that such objects will not evaporate completely, but leave a stable remnant. For the purpose of defining a reference scenario, we have employed the publicly available Monte Carlo generator CHARYBDIS2, in which the remnant's behavior is mostly determined by kinematic constraints and conservation of some quantum numbers, such as the baryon charge. Our findings show that electrically neutral remnants are highly favored and a significantly larger amount of missing transverse momentum is to be expected with respect to the case of complete decay.

L. Bellagamba; R. Casadio; R. Di Sipio; V. Viventi

2012-01-16T23:59:59.000Z

220

Primordial black holes as biased tracers  

E-Print Network [OSTI]

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...

Tada, Yuichiro

2015-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "hydroprobe slim holes" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Probing the puncture for black hole simulations  

SciTech Connect (OSTI)

With the puncture method for black hole simulations, the second infinity of a wormhole geometry is compactified to a single 'puncture point' on the computational grid. The region surrounding the puncture quickly evolves to a trumpet geometry. The computational grid covers only a portion of the trumpet throat. It ends at a boundary whose location depends on resolution. This raises the possibility that perturbations in the trumpet geometry could propagate down the trumpet throat, reflect from the puncture boundary, and return to the black hole exterior with a resolution-dependent time delay. Such pathological behavior is not observed. This is explained by the observation that some perturbative modes propagate in the conformal geometry, others propagate in the physical geometry. The puncture boundary exists only in the physical geometry. The modes that propagate in the physical geometry are always directed away from the computational domain at the puncture boundary. The finite difference stencils ensure that these modes are advected through the boundary with no coupling to the modes that propagate in the conformal geometry. These results are supported by numerical experiments with a code that evolves spherically symmetric gravitational fields with standard Cartesian finite difference stencils. The code uses the Baumgarte-Shapiro-Shibata-Nakamura formulation of Einstein's equations with 1+log slicing and gamma-driver shift conditions.

Brown, J. David [Department of Physics, North Carolina State University, Raleigh, North Carolina 27695 (United States)

2009-10-15T23:59:59.000Z

222

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

E-Print Network [OSTI]

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.

Wontae Kim; Edwin J. Son; Myungseok Yoon

2008-01-09T23:59:59.000Z

223

Intermediate-Mass Black Holes as LISA Sources  

E-Print Network [OSTI]

Intermediate-mass black holes (IMBHs), with masses of hundreds to thousands of solar masses, will be unique sources of gravitational waves for LISA. Here we discuss their context as well as specific characteristics of IMBH-IMBH and IMBH-supermassive black hole mergers and how these would allow sensitive tests of the predictions of general relativity in strong gravity.

M. Coleman Miller

2008-12-16T23:59:59.000Z

224

Binary Black Hole Accretion Flows in Merged Galactic Nuclei  

Science Journals Connector (OSTI)

......for Theoretical Physics, Oiwake-cho...when the gas can pass across the maximum...mass-capture rates are eventually...holes|black hole physics|galaxies: nuclei...when the gas can pass across the maximum...mass-capture rates exhibit little...for Theoretical Physics (YITP) of Kyoto......

Kimitake Hayasaki; Shin Mineshige; Hiroshi Sudou

2007-04-25T23:59:59.000Z

225

Quasar evolution and the growth of black holes  

Science Journals Connector (OSTI)

......hole which accretes at a rate that is ultimately limited...intermittently at an average rate that is a universal function...that the mean accretion rate scales as M 1.5 t 6...sufficiently massive galaxies pass through a quasar phase...accretion discs|black hole physics|galaxies: active......

Todd A. Small; Roger D. Blandford

1992-12-15T23:59:59.000Z

226

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

227

Evaluating an icon of population persistence: the Devil's Hole pupfish  

Science Journals Connector (OSTI)

...research-article Research articles 1001 60 197 Evaluating an icon of population persistence: the Devil's Hole pupfish J. Michael...Based on our analyses, we conclude that rather than being an icon of unusual persistence in isolation, the Devil's Hole pupfish...

2014-01-01T23:59:59.000Z

228

Synchronous Black Hole Search in Directed Graphs Adrian Kosowski  

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

229

Modified Black Hole with Polar Jet and Vortex  

E-Print Network [OSTI]

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.

T. Tmmalm

2001-12-06T23:59:59.000Z

230

Electromagnetic extraction of energy from Kerr black holes  

E-Print Network [OSTI]

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.

Isao Okamoto

2005-06-14T23:59:59.000Z

231

Black holes at the IceCube neutrino telescope  

Science Journals Connector (OSTI)

If the fundamental Planck scale is about a TeV and the cosmic neutrino flux is at the Waxman-Bahcall level, quantum black holes are created daily in the Antarctic ice cap. We reexamine the prospects for observing such black holes with the IceCube neutrino-detection experiment. To this end, we first revise the black hole production rate by incorporating the effects of inelasticty, i.e., the energy radiated in gravitational waves by the multipole moments of the incoming shock waves. After that we study in detail the process of Hawking evaporation accounting for the black holes large momentum in the lab system. We derive the energy spectrum of the Planckian cloud which is swept forward with a large, O(106), Lorentz factor. (It is noteworthy that the boosted thermal spectrum is also relevant for the study of near-extremal supersymmetric black holes, which could be copiously produced at the Large Hadron Collider.) In the semiclassical regime, we estimate the average energy of the boosted particles to be less than 20% the energy of the ? progenitor. Armed with such a constraint, we determine the discovery reach of IceCube by tagging on soft (relative to what one would expect from charged current standard model processes) muons escaping the electromagnetic shower bubble produced by the black holes light descendants. The statistically significant 5? excess extends up to a quantum gravity scale ?1.3??TeV.

Luis A. Anchordoqui; Matthew M. Glenz; Leonard Parker

2007-01-09T23:59:59.000Z

232

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

E-Print Network [OSTI]

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.

Stefan Hollands; Akihiro Ishibashi

2014-08-04T23:59:59.000Z

233

E-Print Network 3.0 - access hole parameters Sample Search Results  

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

features in this regime whenever the quantum dot hole level is resonant with two... -dimensional hole states located at the capping layer-blocking barrier interface in our...

234

Fuel injector Holes (Fabrication of Micro-Orifices for Fuel Injectors...  

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

injector Holes (Fabrication of Micro-Orifices for Fuel Injectors) Fuel injector Holes (Fabrication of Micro-Orifices for Fuel Injectors) 2009 DOE Hydrogen Program and Vehicle...

235

Thermal Gradient Holes At Coso Geothermal Area (1976) | Open Energy  

Open Energy Info (EERE)

Thermal Gradient Holes At Coso Geothermal Area (1976) Thermal Gradient Holes At Coso Geothermal Area (1976) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Thermal Gradient Holes At Coso Geothermal Area (1976) Exploration Activity Details Location Coso Geothermal Area Exploration Technique Thermal Gradient Holes Activity Date 1976 Usefulness useful DOE-funding Unknown Notes Temperatures have been obtained to depths up to 133 m in 22 boreholes with measurements being made at least four times in each borehole. Geothermal gradients ranged from 240C/km to 450 0C/km. References Combs, J. (1 December 1976) Heat flow determinations and implied thermal regime of the Coso geothermal area, California Retrieved from "http://en.openei.org/w/index.php?title=Thermal_Gradient_Holes_At_Coso_Geothermal_Area_(1976)&oldid=511217"

236

Hypervelocity binary stars: smoking gun of massive binary black holes  

E-Print Network [OSTI]

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.

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

2007-07-12T23:59:59.000Z

237

Experimental Signature for Black Hole Production in Neutrino Air Showers  

E-Print Network [OSTI]

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.

Luis Anchordoqui; Haim Goldberg

2001-10-15T23:59:59.000Z

238

Extremal black holes and the first law of thermodynamics  

Science Journals Connector (OSTI)

We study the low-temperature expansion of the first law of thermodynamics for near-extremal black holes. We show that for extremal black holes with nonvanishing entropy, the leading-order contribution yields an expression for their extremal entropy that is in agreement with the entropy-function result. When their entropy vanishes due to the vanishing of a one-cycle on the horizon, such a leading contribution is always compatible with the first law satisfied by a Baados-Teitelboim-Zanelli black hole. The universality of these results follows from universal facts about extremal black holes. Our results are consistent with both the presence of local AdS2 and AdS3 near-horizon throats for extremal black holes and with the suggested quantum microscopic descriptions (AdS2/CFT1, Kerr/CFT, and extremal vanishing horizon/CFT).

Maria Johnstone; M. M. Sheikh-Jabbari; Joan Simn; Hossein Yavartanoo

2013-11-27T23:59:59.000Z

239

Thermal Gradient Holes At Central Nevada Seismic Zone Region (Pritchett,  

Open Energy Info (EERE)

Thermal Gradient Holes At Central Nevada Seismic Zone Region (Pritchett, Thermal Gradient Holes At Central Nevada Seismic Zone Region (Pritchett, 2004) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Thermal Gradient Holes At Central Nevada Seismic Zone Region (Pritchett, 2004) Exploration Activity Details Location Central Nevada Seismic Zone Geothermal Region Exploration Technique Thermal Gradient Holes Activity Date Usefulness useful DOE-funding Unknown Notes NOTE: These are theoretical/computer simulation tests of various methods on eight hypothetical 'model' basing-and-range geothermal systems. "The 300-meter heat flow holes are essentially useless for finding the "hidden" reservoirs. Clearly, the best results are obtained from the SP and MT surveys, with DC resistivity a close third. It is concluded that the best

240

What's Wrong With Black Hole Thermodynamics?  

E-Print Network [OSTI]

Not only is the Bekenstein expression for the entropy of a black hole a convex function of the energy, rather than being a concave function as it must be, it predicts a final equilibrium temperature given by the harmonic mean. This violates the third law, and the principle of maximum work. The property that means are monotonically increasing functions of their argument underscores the error of transferring from temperature means to means in the internal energy when the energy is not a monotonically increasing function of temperature. Whereas the former leads to an increase in entropy, the latter lead to a decrease in entropy thereby violating the second law. The internal energy cannot increase at a slower rate than the temperature itself.

B. H. Lavenda

2011-10-23T23:59:59.000Z

Note: This page contains sample records for the topic "hydroprobe slim holes" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

The Galactic Center Black Hole Laboratory  

E-Print Network [OSTI]

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.

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

242

Slim completions offer limited stimulation variances: Part 3  

SciTech Connect (OSTI)

This is the third in a series of five articles addressing barriers to increased US utilization of slimhole drilling and completion techniques. Previous articles discussed slimhole drilling and cementing. The focus of this article is stimulation, with an emphasis on hydraulic fracturing. This series is based on a study conducted for Gas Research institute (GRI) by an industry team consisting of Maurer Engineering, BJ Services, Baker Oil tools, and Halliburton. Parts 1 and 2 were published in the September and October 1994 issues of Petroleum Engineer International, respectively. Potential cost saving resulting from slimhole drilling and completions of gas wells are often inhibited by the limitations on hydraulic fracturing. Variances from conventional fracturing include excessive friction pressure, fracture fluid degradation due to excessive shear rates, proppant bridging and limited diverting options.

Brunsman, B.J. (Gas Research Inst., Chicago, IL (United States)); Matson, R. (BJ Services Co., Tomball, TX (United States)); Shook, R.A. (Maurer Engineering Inc., Houston, TX (United States))

1994-12-01T23:59:59.000Z

243

SLIM: A Scalable Location-Sensitive Information Monitoring Service  

E-Print Network [OSTI]

. A typical example of such services is "alert me when the gas price at a gas station within 5 miles of my gas prices at gas stations, traffic conditions at major junctions or pollution levels in different-spatial predicates. For example, a user may install a trigger of the form "alert when within one mile of gas station

Liu, Ling

244

Slim Lake, Minnesota: Energy Resources | Open Energy Information  

Open Energy Info (EERE)

0234235°, -91.9938415° 0234235°, -91.9938415° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":48.0234235,"lon":-91.9938415,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

245

Optical transitions of holes in uniaxially compressed germanium  

SciTech Connect (OSTI)

Spontaneous emission and photoconductivity of germanium with gallium impurity are studied for determining the energy spectrum of hole states in this material in which radiation can be induced as a result of transitions of holes between these states. Holes were excited by electric field pulses with a strength up to 12 kV/cm at T = 4.2 K under uniaxial compression of samples up to 12 kbar. It has been found that hole emission spectra for transitions between resonant and local states of the impurity have a structure identical to the photoconductivity and absorption spectra. Transitions from resonance states, which are associated with the heavy hole subband, have not been detected. It has been found that in an electric field lower than 100 V/cm, a compressed crystal emits as a result of transitions of heavy holes. In a strong electric field (1-3 kV/cm), emission is observed in the energy range up to 140 meV, and transitions with emission of TA and LO phonons appear in such a field. The emission spectra under pressures of 0 and 12 kbar differ insignificantly. Hence, it follows that the contributions from heavy and light holes in a strong electric field are indistinguishable.

Pokrovskii, Ya. E., E-mail: yaep@cplire.ru; Khvalkovskii, N. A. [Russian Academy of Sciences, Kotel'nikov Institute of Radio Engineering and Electronics (Russian Federation)] [Russian Academy of Sciences, Kotel'nikov Institute of Radio Engineering and Electronics (Russian Federation)

2013-10-15T23:59:59.000Z

246

Relativistic hydrodynamics in the presence of puncture black holes  

SciTech Connect (OSTI)

Many of the recent numerical simulations of binary black holes in vacuum adopt the moving puncture approach. This successful approach avoids the need to impose numerical excision of the black hole interior and is easy to implement. Here we wish to explore how well the same approach can be applied to moving black hole punctures in the presence of relativistic hydrodynamic matter. First, we evolve single black hole punctures in vacuum to calibrate our Baumgarte-Shapiro-Shibata-Nakamura implementation and to confirm that the numerical solution for the exterior spacetime is invariant to any junk (i.e., constraint-violating) initial data employed in the black hole interior. Then we focus on relativistic Bondi accretion onto a moving puncture Schwarzschild black hole as a numerical test bed for our high-resolution shock-capturing relativistic hydrodynamics scheme. We find that the hydrodynamical equations can be evolved successfully in the interior without imposing numerical excision. These results help motivate the adoption of the moving puncture approach to treat the binary black hole-neutron star problem using conformal thin-sandwich initial data.

Faber, Joshua A.; Etienne, Zachariah B.; Shapiro, Stuart L.; Taniguchi, Keisuke [Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States); Baumgarte, Thomas W. [Department of Physics and Astronomy, Bowdoin College, Brunswick, Maine 04011 (United States)

2007-11-15T23:59:59.000Z

247

Nonphotochemical hole burning and dispersive kinetics in amorphous solids  

SciTech Connect (OSTI)

Results covering burn intensities in the nW to {mu}W/cm{sup 2} range, of dispersive hole growth kinetics are reported for Oxazine 720 in glycerol glasses and polyvinyl alcohol polymer films and their deuterated analogues. A theoretical model which employs a distribution function for the hole burning rate constant based upon a Gaussian distribution for the tunnel parameter is shown to accurately describe the kinetic data. This model incorporates the linear electron-phonon coupling. A method for calculating the nonphotochemical quantum yield is presented which utilizes the Gaussian distribution of tunnel parameters. The quantum yield calculation can be extended to determine a quantum yield as a function of hole depth. The effect of spontaneous hole filling is shown to be insignificant over the burn intensity range studied. Average relaxation rates for hole burning are {approximately}8 orders of magnitude greater than for hole filling. The dispersive kinetics of hole burning are observed to be independent over the temperature range of these experiments, 1.6 to 7.0 K. 6 refs., 20 figs., 1 tab.

Kenney, M.J.

1990-09-21T23:59:59.000Z

248

Gauss-Bonnet black holes in dS spaces  

Science Journals Connector (OSTI)

We study the thermodynamic properties associated with the black hole horizon and cosmological horizon for the Gauss-Bonnet solution in de Sitter space. When the Gauss-Bonnet coefficient is positive, a locally stable small black hole appears in the case of spacetime dimension d=5, the stable small black hole disappears, and the Gauss-Bonnet black hole is always unstable quantum mechanically when d>~6. On the other hand, the cosmological horizon is found to be always locally stable independent of the spacetime dimension. But the solution is not globally preferred; instead, the pure de Sitter space is globally preferred. When the Gauss-Bonnet coefficient is negative, there is a constraint on the value of the coefficient, beyond which the gravity theory is not well defined. As a result, there is not only an upper bound on the size of black hole horizon radius at which the black hole horizon and cosmological horizon coincide with each other, but also a lower bound depending on the Gauss-Bonnet coefficient and spacetime dimension. Within the physical phase space, the black hole horizon is always thermodynamically unstable and the cosmological horizon is always stable; furthermore, as in the case of the positive coefficient, the pure de Sitter space is still globally preferred. This result is consistent with the argument that the pure de Sitter space corresponds to an UV fixed point of dual field theory.

Rong-Gen Cai and Qi Guo

2004-05-26T23:59:59.000Z

249

Acoustic white holes in flowing atomic Bose-Einstein condensates  

E-Print Network [OSTI]

We study acoustic white holes in a steadily flowing atomic Bose-Einstein condensate. A white hole configuration is obtained when the flow velocity goes from a super-sonic value in the upstream region to a sub-sonic one in the downstream region. The scattering of phonon wavepackets on a white hole horizon is numerically studied in terms of the Gross-Pitaevskii equation of mean-field theory: dynamical stability of the acoustic white hole is found, as well as a signature of a nonlinear back-action of the incident phonon wavepacket onto the horizon. The correlation pattern of density fluctuations is numerically studied by means of the truncated-Wigner method which includes quantum fluctuations. Signatures of the white hole radiation of correlated phonon pairs by the horizon are characterized; analogies and differences with Hawking radiation from acoustic black holes are discussed. In particular, a short wavelength feature is identified in the density correlation function, whose amplitude steadily grows in time since the formation of the horizon. The numerical observations are quantitatively interpreted by means of an analytical Bogoliubov theory of quantum fluctuations for a white hole configuration within the step-like horizon approximation.

Carlos Mayoral; Alessio Recati; Alessandro Fabbri; Renaud Parentani; Roberto Balbinot; Iacopo Carusotto

2010-09-30T23:59:59.000Z

250

Black Holes and the Third Law of Thermodynamics  

E-Print Network [OSTI]

We discuss in the framework of black hole thermodynamics some aspects relative to the third law in the case of black holes of the Kerr-Newman family. In the light of the standard proof of the equivalence between the unattainability of the zero temperature and the entropic version of the third law it is remarked that the unattainability has a special character in black hole thermodynamics. Also the zero temperature limit which obtained in the case of very massive black holes is discussed and it is shown that a violation of the entropic version in the charged case occurs. The violation of the Bekenstein-Hawking law in favour of zero entropy S_E=0 in the case of extremal black holes is suggested as a natural solution for a possible violation of the second law of thermodynamics. Thermostatic arguments in support of the unattainability are explored, and $S_E=0$ for extremal black holes is shown to be again a viable solution. The third law of black hole dynamics by W.Israel is then interpreted as a further strong corroboration to the picture of a discontinuity between extremal states and non-extremal ones.

F. Belgiorno; M. Martellini

2002-10-08T23:59:59.000Z

251

Dynamical evolution of quasi-circular binary black hole data  

E-Print Network [OSTI]

We study the fully nonlinear dynamical evolution of binary black hole data, whose orbital parameters are specified via the effective potential method for determining quasi-circular orbits. The cases studied range from the Cook-Baumgarte innermost stable circular orbit (ISCO) to significantly beyond that separation. In all cases we find the black holes to coalesce (as determined by the appearance of a common apparent horizon) in less than half an orbital period. The results of the numerical simulations indicate that the initial holes are not actually in quasi-circular orbits, but that they are in fact nearly plunging together. The dynamics of the final horizon are studied to determine physical parameters of the final black hole, such as its spin, mass, and oscillation frequency, revealing information about the inspiral process. We show that considerable resolution is required to extract accurate physical information from the final black hole formed in the merger process, and that the quasi-normal modes of the final hole are strongly excited in the merger process. For the ISCO case, by comparing physical measurements of the final black hole formed to the initial data, we estimate that less than 3% of the total energy is radiated in the merger process.

Miguel Alcubierre; Bernd Bruegmann; Peter Diener; F. Siddhartha Guzman; Ian Hawke; Scott Hawley; Frank Herrmann; Michael Koppitz; Denis Pollney; Edward Seidel; Jonathan Thornburg

2004-11-30T23:59:59.000Z

252

Scalar emission in a rotating Gdel black hole  

E-Print Network [OSTI]

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.

Songbai Chen; Bin Wang; Jiliang Jing

2008-08-23T23:59:59.000Z

253

Accretion onto a black hole in a string cloud background  

E-Print Network [OSTI]

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 $\\alpha$.

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

2014-09-28T23:59:59.000Z

254

Phenomenological Description of the Interior of the Schwarzschild Black Hole  

E-Print Network [OSTI]

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\

Hikaru Kawai; Yuki Yokokura

2014-09-19T23:59:59.000Z

255

Three-dimensional Chern-Simons black holes  

SciTech Connect (OSTI)

We construct black hole solutions to three-dimensional Einstein-Maxwell theory with both gravitational and electromagnetic Chern-Simons terms. These intrinsically rotating solutions are geodesically complete, and causally regular within a certain parameter range. Their mass, angular momentum and entropy are found to satisfy the first law of black hole thermodynamics. These Chern-Simons black holes admit a four-parameter local isometry algebra, which generically is sl(2,R)xR, and may be generated from the corresponding vacua by local coordinate transformations.

Moussa, Karim Ait [Laboratoire de Physique Mathematique et Physique Subatomique, Departement de Physique, Faculte des Sciences, Universite Mentouri, Constantine 25000 (Algeria); Clement, Gerard; Leygnac, Cedric [Laboratoire de Physique Theorique LAPTH (CNRS), B.P.110, F-74941 Annecy-le-Vieux cedex (France); Guennoune, Hakim [Laboratoire de Physique Theorique LAPTH (CNRS), B.P.110, F-74941 Annecy-le-Vieux cedex (France); Departement de Physique, Faculte des Sciences, Universite Ferhat Abbas, Setif 19000 (Algeria)

2008-09-15T23:59:59.000Z

256

Black hole evaporation within a momentum-dependent metric  

SciTech Connect (OSTI)

We investigate the black hole thermodynamics in a 'deformed' relativity framework where the energy-momentum dispersion law is Lorentz-violating and the Schwarzchild-like metric is momentum-dependent with a Planckian cutoff. We obtain net deviations of the basic thermodynamical quantities from the Hawking-Bekenstein predictions: actually, the black hole evaporation is expected to quit at a nonzero critical mass value (of the order of the Planck mass), leaving a zero temperature remnant, and avoiding a spacetime singularity. Quite surprisingly, the present semiclassical corrections to black hole temperature, entropy, and heat capacity turn out to be identical to the ones obtained within some quantum approaches.

Salesi, G.; Di Grezia, E. [Universita Statale di Bergamo, Facolta di Ingegneria, viale Marconi 5, I-24044 Dalmine (Italy) and Istituto Nazionale di Fisica Nucleare, Sezione di Milano, via Celoria 16, I-20133 Milan (Italy)

2009-05-15T23:59:59.000Z

257

Inferring black hole charge from backscattered electromagnetic radiation  

E-Print Network [OSTI]

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.

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

2014-09-16T23:59:59.000Z

258

Hawking Radiation by Kerr Black Holes and Conformal Symmetry  

SciTech Connect (OSTI)

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.

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

259

Quantum Dot Light-Emitting Diode with Quantum Dots Inside the Hole Transporting Layers  

E-Print Network [OSTI]

architecture using a noninverted structure with the QDs sandwiched between hole transporting layers (HTLs

Demir, Hilmi Volkan

260

Probing Core-Hole Localization in Molecular Nitrogen  

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

Probing Core-Hole Localization in Molecular Nitrogen Print Probing Core-Hole Localization in Molecular Nitrogen Print The behavior of the core hole created in molecular x-ray photoemission experiments has provided molecular scientists with a valuable window through which to probe the electronic structure and dynamics of molecules. But the answer to one fundamental quantum question-whether the core hole is localized or delocalized-has remained elusive for diatomic molecules in which both atoms are the same element. An international team of scientists from the University of Frankfurt in Germany, Berkeley Lab, Kansas State University, and Auburn University has now resolved the issue with an appropriate twist of quantum fuzziness. By means of coincident detection of the photoelectron ejected from molecular nitrogen and the Auger electron emitted femtoseconds later, the team found that how the measurements are done determines which description-localized or delocalized-is valid.

Note: This page contains sample records for the topic "hydroprobe slim holes" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Probing Core-Hole Localization in Molecular Nitrogen  

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

Probing Core-Hole Localization in Molecular Nitrogen Print Probing Core-Hole Localization in Molecular Nitrogen Print The behavior of the core hole created in molecular x-ray photoemission experiments has provided molecular scientists with a valuable window through which to probe the electronic structure and dynamics of molecules. But the answer to one fundamental quantum question-whether the core hole is localized or delocalized-has remained elusive for diatomic molecules in which both atoms are the same element. An international team of scientists from the University of Frankfurt in Germany, Berkeley Lab, Kansas State University, and Auburn University has now resolved the issue with an appropriate twist of quantum fuzziness. By means of coincident detection of the photoelectron ejected from molecular nitrogen and the Auger electron emitted femtoseconds later, the team found that how the measurements are done determines which description-localized or delocalized-is valid.

262

Geological and geophysical analysis of Coso Geothermal Exploration Hole No.  

Open Energy Info (EERE)

and geophysical analysis of Coso Geothermal Exploration Hole No. and geophysical analysis of Coso Geothermal Exploration Hole No. 1 (CGEH-1), Coso Hot Springs KGRA, California Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Report: Geological and geophysical analysis of Coso Geothermal Exploration Hole No. 1 (CGEH-1), Coso Hot Springs KGRA, California Details Activities (5) Areas (1) Regions (0) Abstract: The Coso Geothermal Exploration Hole number one (CGEH-1) was drilled in the Coso Hot Springs KGRA, California, from September 2 to December 2, 1977. Chip samples were collected at ten foot intervals and extensive geophysical logging surveys were conducted to document the geologic character of the geothermal system as penetrated by CGEH-1. The major rock units encountered include a mafic metamorphic sequence and a

263

Core Holes At Long Valley Caldera Geothermal Area (Benoit, 1984...  

Open Energy Info (EERE)

Basis Several core holes were also drilled in the caldera's west moat by Phillips Petroleum Company in 1982, including: PLV-1, drilled to approximately 711 m depth PLV-2,...

264

Search for gravitational waves from intermediate mass binary black holes  

E-Print Network [OSTI]

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 ...

Barsotti, Lisa

265

Primary caustics and critical points behind a Kerr black hole  

SciTech Connect (OSTI)

The primary optical caustic surface behind a Kerr black hole is a four-cusped tube displaced from the line of sight. We derive the caustic surface in the nearly asymptotic region far from the black hole through a Taylor expansion of the lightlike geodesics up to and including fourth-order terms in m/b and a/b, where m is the black hole mass, a the spin, and b the impact parameter. The corresponding critical locus in the observer's sky is elliptical and a pointlike source inside the caustics will be imaged as an Einstein cross. With regard to lensing near critical points, a Kerr lens is analogous to a circular lens perturbed by a dipole and a quadrupole potential. The caustic structure of the supermassive black hole in the Galactic center could be probed by lensing of low mass x-ray binaries in the galactic inner regions or by hot spots in the accretion disk.

Sereno, Mauro; De Luca, Fabiana [Institut fuer Theoretische Physik, Universitaet Zuerich, Winterthurerstrasse 190, CH-8057 Zuerich (Switzerland)

2008-07-15T23:59:59.000Z

266

Analytical Kerr black hole lensing in the weak deflection limit  

Science Journals Connector (OSTI)

We present an analytical treatment of gravitational lensing by a Kerr black hole in the weak deflection limit. Lightlike geodesics are expanded as a Taylor series up to and including third-order terms in m/b and a/b, where m is the black hole mass, a the angular momentum, and b the impact parameter of the light ray. Positions and magnifications of individual images are computed with a perturbative analysis. At this order, the degeneracy with the translated Schwarzschild lens is broken. The critical curve is still a circle displaced from the black hole position in the equatorial direction and the corresponding caustic is pointlike. The degeneracy between the black hole spin and its inclination relative to the observer is broken through the angular coordinates of the perturbed images.

Mauro Sereno and Fabiana De Luca

2006-12-21T23:59:59.000Z

267

Primary caustics and critical points behind a Kerr black hole  

Science Journals Connector (OSTI)

The primary optical caustic surface behind a Kerr black hole is a four-cusped tube displaced from the line of sight. We derive the caustic surface in the nearly asymptotic region far from the black hole through a Taylor expansion of the lightlike geodesics up to and including fourth-order terms in m/b and a/b, where m is the black hole mass, a the spin, and b the impact parameter. The corresponding critical locus in the observers sky is elliptical and a pointlike source inside the caustics will be imaged as an Einstein cross. With regard to lensing near critical points, a Kerr lens is analogous to a circular lens perturbed by a dipole and a quadrupole potential. The caustic structure of the supermassive black hole in the Galactic center could be probed by lensing of low mass x-ray binaries in the galactic inner regions or by hot spots in the accretion disk.

Mauro Sereno and Fabiana De Luca

2008-07-09T23:59:59.000Z

268

On black hole evolution in active galactic nuclei  

Science Journals Connector (OSTI)

......whether higher accretion rates during low activity periods...accretion discs|black hole physics|galaxies: active|galaxies...the decreasing accretion rate must pass through the range of intermediate accretion rates ( _10-3 .AEdd)' At......

R. Moderski; M. Sikora

1996-12-01T23:59:59.000Z

269

Neural network calibration for miniature multi-hole pressure probes  

E-Print Network [OSTI]

A robust and accurate neural network based algorithm phics. for the calibration of miniature multi-hole pressure probes has been developed and a detailed description of its features and use is presented. The code that was developed was intended...

Vijayagopal, Rajesh

1998-01-01T23:59:59.000Z

270

Quantum Emission from Two-Dimensional Black Holes  

E-Print Network [OSTI]

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.

Steven B. Giddings; W. M. Nelson

2009-11-27T23:59:59.000Z

271

The Energy for 2+1 Dimensional Black Hole Solutions  

E-Print Network [OSTI]

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.

I-Ching Yang; Irina Radinschi

2006-11-05T23:59:59.000Z

272

Applying multiwell normalization in open hole log analysis  

E-Print Network [OSTI]

A major problem when analyzing open hole well logging data in large fields is the fact that the logs were run using different logging service companies, using different logging tools over a long time span. To obtain correct log interpretations...

Sinanan, Haydn Brent

2012-06-07T23:59:59.000Z

273

Nonphotochemical hole burning and dispersive kinetics in amorphous solids.  

E-Print Network [OSTI]

??Results of an extensive study, covering burn intensities in the nW to {dollar}?{dollar}W/cm{dollar}2{dollar} range, of dispersive hole growth kinetics are reported for Oxazine 720 in (more)

Kenney, Michael Joseph

1990-01-01T23:59:59.000Z

274

Port hole perturbations to the magnetic field in MST  

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

095002 (17pp) doi:10.10880741-3335529095002 Port hole perturbations to the magnetic field in MST P J Fimognari 1 , A F Almagri 1 , J K Anderson 1 , D R Demers 2 , J S Sarff 1 ,...

275

Lovelock black holes in a string cloud background  

E-Print Network [OSTI]

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.

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

2014-09-12T23:59:59.000Z

276

General solutions for thermopiezoelectrics with various holes under thermal loading  

E-Print Network [OSTI]

induced by thermal loads. The loads may be uniform remote heat ¯ow, point heat source and temperature elastic plate with an hole of various shapes subjected to remote uniform mechanical loading. For plane

Qin, Qinghua

277

Extremal Black Holes and First Law of Thermodynamics  

E-Print Network [OSTI]

We study the low temperature expansion of the first law of thermodynamics for near-extremal black holes. We show that for extremal black holes with non-vanishing entropy, the leading order contribution yields an expression for their extremal entropy in agreement with the entropy function result and the Cardy formula for the entropy of a two dimensional chiral conformal field theory (CFT). When their entropy vanishes due to the vanishing of a one-cycle on the horizon, such leading contribution is always compatible with the first law satisfied by a BTZ black hole. These results are universal and consistent both with the presence of local AdS2 and AdS3 near horizon throats for extremal black holes and with the suggested quantum microscopic descriptions (AdS2/CFT1, Kerr/CFT and EVH/CFT).

Maria Johnstone; M. M. Sheikh-Jabbari; Joan Simon; Hossein Yavartanoo

2013-05-14T23:59:59.000Z

278

Thermodynamics and Thermodynamic geometry of Park black hole  

E-Print Network [OSTI]

We study the thermodynamics and thermodynamic geometry of Park black hole in Ho\\v{r}ava gravity. By incorporating the ideas of differential geometry, we have investigated the thermodynamics using Weinhold geometry and Ruppeiner geometry. We have also analyzed it in the context of newly developed geometrothermodynamics(GTD). Divergence of specific heat is associated with the second order phase transition of black hole. Here in the context of Park black hole, both Weinhold's metric and Ruppeiner's metric well explain this phase transition. But these explanations depend on the choice of potential. Hence the Legendre invariant GTD is used, and with the true singularities in the curvature scalar, GTD well explain the second order phase transition. All these methods together give an exact idea of all the behaviors of the Park black hole thermodynamics.

Jishnu Suresh; Tharanath R; Nijo Varghese; V C Kuriakose

2014-03-19T23:59:59.000Z

279

Core Holes At Valles Caldera - Sulphur Springs Geothermal Area...  

Open Energy Info (EERE)

Dennis L. Nielson, Pisto Larry, C.W. Criswell, R. Gribble, K. Meeker, J.A. Musgrave, T. Smith, D. Wilson (1989) Scientific Core Hole Valles Caldera No. 2B (VC-2B), New Mexico:...

280

Temperatures, heat flow, and water chemistry from drill holes...  

Open Energy Info (EERE)

Temperatures, heat flow, and water chemistry from drill holes in the Raft River geothermal system, Cassia County, Idaho Jump to: navigation, search OpenEI Reference LibraryAdd to...

Note: This page contains sample records for the topic "hydroprobe slim holes" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

T-693: Symantec Endpoint Protection Manager Input Validation Hole Permits  

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

3: Symantec Endpoint Protection Manager Input Validation Hole 3: Symantec Endpoint Protection Manager Input Validation Hole Permits Cross-Site Scripting and Cross-Site Request Forgery Attacks T-693: Symantec Endpoint Protection Manager Input Validation Hole Permits Cross-Site Scripting and Cross-Site Request Forgery Attacks August 15, 2011 - 3:42pm Addthis PROBLEM: Two vulnerabilities were reported in Symantec Endpoint Protection Manager. A remote user can conduct cross-site scripting attacks. A remote user can conduct cross-site request forgery attacks. PLATFORM: Version(s): 11.0 RU6(11.0.600x), 11.0 RU6-MP1(11.0.6100), 11.0 RU6-MP2(11.0.6200), 11.0 RU6-MP3(11.0.6300) ABSTRACT: Symantec Endpoint Protection Manager Input Validation Hole Permits Cross-Site Scripting and Cross-Site Request Forgery Attacks. reference LINKS:

282

Particle acceleration by Majumdar-Papapetrou di-hole  

E-Print Network [OSTI]

We explore the multi-black hole spacetimes from the perspective of the ultra-high energy particle collisions. Such a discussion is limited to the spacetimes containing a single black hole so far. We deal with the Majumdar-Papapetrou solution representing a system consisting of two identical black holes in the equilibrium. In order to identify the conditions suitable for the process of high energy collisions, we consider particles confined to move on the equatorial plane towards the axis of symmetry with the zero angular momentum. We consider collision between the particles moving in opposite directions at the location midway between the black holes on the axis. We show that the center of mass energy of collision between the particles increases with the decrease in the separation between the black holes and shows divergence in the limit where the separation goes to zero. We estimate the size of the region close to the central point on the equatorial plane where it would be possible to have high energy collisions and show that this region has a reasonably large spatial extent. We further explore the process of high energy collisions with the general geodesics with arbitrary angular momentum on the equatorial plane away from the central point. Although in this paper we deal with theMajumdar-Papapetrou spacetime which serves as a toy example representing multiple black holes, we speculate on the possibility that the ultra-high energy collisions would also occur in the more general setting like colliding black holes, when distance between the black holes is extremely small, which can in principle be verified in the numerical relativity simulations.

Mandar Patil; Pankaj S. Joshi

2014-09-03T23:59:59.000Z

283

Remarks about Static Back-Reaction on Black Hole Spacetimes  

E-Print Network [OSTI]

Recently, it has been claimed that the back reaction of vacuum polarization on a black hole spacetime naturally regularizes infinities in the black hole entropy. We examine the back reaction calculation and find no such short-distance cut-off,in contradiction with these recent claims. Moreover, the intuitive expectation that the perturbative calculation breaks down near the event horizon is confirmed. The new surface gravity diverges and the metric is degenerate at the stretched horizon.

Neil J. Cornish; Janna J. Levin

1994-11-13T23:59:59.000Z

284

Black holes and structure in an oscillating universe  

Science Journals Connector (OSTI)

... a = 27 irG2 M2 / c4 is the radiation capture cross-section for a Schwarzschild black hole. This assumes that black holes accrete independently in a uniform radiation field ... cm and rA = (81/64)c?1r0>Sch s where rOSch is the initial Schwarzschild radius (c.g.s. units). Thus A?1016cm, corresponding to rA?10? ...

William C. Saslaw

1991-03-07T23:59:59.000Z

285

Overspinning a Black Hole with a Test Body  

Science Journals Connector (OSTI)

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

Ted Jacobson and Thomas P. Sotiriou

2009-09-28T23:59:59.000Z

286

On the Quantum-Corrected Black Hole Thermodynamics  

E-Print Network [OSTI]

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.

Kourosh Nozari; S. Hamid Mehdipour

2005-04-21T23:59:59.000Z

287

Woods Hole Research Center Wind Turbine | Open Energy Information  

Open Energy Info (EERE)

Hole Research Center Wind Turbine Hole Research Center Wind Turbine Jump to: navigation, search Name Woods Hole Research Center Wind Turbine Facility Woods Hole Research Center Wind Turbine Sector Wind energy Facility Type Small Scale Wind Facility Status In Service Owner Woods Hole Research Center Developer Sustainable Energy Developments Energy Purchaser Woods Hole Research Center Location Falmouth MA Coordinates 41.548637°, -70.64326° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":41.548637,"lon":-70.64326,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

288

Nearly extremal apparent horizons in simulations of merging black holes  

E-Print Network [OSTI]

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.)

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

289

Black Hole Instabilities and Exponential Growth  

E-Print Network [OSTI]

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 $...

Prabhu, Kartik

2015-01-01T23:59:59.000Z

290

Conformal Symmetry of a Black Hole as a Scaling Limit: A Black Hole in an Asymptotically Conical Box  

E-Print Network [OSTI]

We show that the previously obtained subtracted geometry of four-dimensional asymptotically flat multi-charged rotating black holes, whose massless wave equation exhibit $SL(2,\\R) \\times SL(2,\\R) \\times SO(3)$ symmetry may be obtained by a suitable scaling limit of certain asymptotically flat multi-charged rotating black holes, which is reminiscent of near-extreme black holes in the dilute gas approximation. The co-homogeneity-two geometry is supported by a dilation field and two (electric) gauge-field strengths. We also point out that these subtracted geometries can be obtained as a particular Harrison transformation of the original black holes. Furthermore the subtracted metrics are asymptotically conical (AC), like global monopoles, thus describing "a black hole in an AC box". Finally we account for the the emergence of the $SL(2,\\R) \\times SL(2,\\R) \\times SO(3)$ symmetry as a consequence of the subtracted metrics being Kaluza-Klein type quotients of $ AdS_3\\times 4 S^3$. We demonstrate that similar properties hold for five-dimensional black holes.

M. Cvetic; G. W. Gibbons

2012-01-03T23:59:59.000Z

291

Ejection of hypervelocity stars by the (binary) black hole(s) in the Galactic center  

E-Print Network [OSTI]

We study three processes that eject hypervelocity (>10^3 km/s) stars from the Galactic center: (i) close encounters of two single stars; (ii) tidal breakup of binary stars by the central black hole, as originally proposed by Hills; and (iii) three-body interactions between a star and a binary black hole (BBH). Mechanism (i) expels hypervelocity stars to the solar radius at a negligible rate, ~10^{-11}/yr. Mechanism (ii) expels hypervelocity stars at a rate ~ 10^{-5}(\\eta/0.1)/yr, where \\eta is the fraction of stars in binaries with semimajor axis a_b<~0.3 AU. For solar-mass stars, the corresponding number of hypervelocity stars within the solar radius R_0=8 kpc is ~60(\\eta/0.1)(a_b/0.1 AU)^{1/2}. For mechanism (iii), Sgr A^* is assumed to be one component of a BBH. We constrain the allowed parameter space (semimajor axis, mass ratio) of the BBH. In the allowed region (for example, semimajor axis of 0.5x10^{-3} pc and mass ratio of 0.01), the rate of ejecting hypervelocity stars can be as large as ~10^{-4}/yr and the expected number of hypervelocity stars within the solar radius can be as large as ~10^3. Hypervelocity stars may be detectable by the next generation of large-scale optical surveys.

Qingjuan Yu; Scott Tremaine

2003-09-03T23:59:59.000Z

292

Black hole firewalls, smoke and mirrors  

Science Journals Connector (OSTI)

The radiation emitted by a black hole (BH) during its evaporation has to have some degree of quantum coherence to accommodate a unitary time evolution. We parametrize the degree of coherence by the number of coherently emitted particles Ncoh and show that it is severely constrained by the equivalence principle. We discuss, in this context, the fate of a shell of matter that falls into a Schwarzschild BH. Two points of view are considered: that of a stationary external observer and that of the shell itself. From the perspective of the shell, the near-horizon region has an energy density proportional to Ncoh2 in Schwarzschild units. So, if Ncoh is parametrically larger than the square root of the BH entropy SBH1/2, a firewall or more generally a wall of smoke forms and the equivalence principle is violated while the BH is still semiclassical. To have a degree of coherence that is parametrically smaller than SBH1/2, one has to introduce a new sub-Planckian gravitational length scale, which likely also violates the equivalence principle. And so our previously proposed model which has Ncoh=SBH1/2 is singled out. From the external-observer perspective, we find that the time it takes for the information about the state of the shell to get re-emitted from the BH is inversely proportional to Ncoh. When the rate of information release becomes of order unity, the semiclassical approximation starts to break down and the BH becomes a perfect reflecting information mirror.

Ram Brustein and A.?J.?M. Medved

2014-07-16T23:59:59.000Z

293

Discovering the QCD Axion with Black Holes and Gravitational Waves  

E-Print Network [OSTI]

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.

Asimina Arvanitaki; Masha Baryakhtar; Xinlu Huang

2014-12-15T23:59:59.000Z

294

Probing Core-Hole Localization in Molecular Nitrogen  

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

Probing Core-Hole Localization Probing Core-Hole Localization in Molecular Nitrogen Probing Core-Hole Localization in Molecular Nitrogen Print Wednesday, 25 February 2009 00:00 The behavior of the core hole created in molecular x-ray photoemission experiments has provided molecular scientists with a valuable window through which to probe the electronic structure and dynamics of molecules. But the answer to one fundamental quantum question-whether the core hole is localized or delocalized-has remained elusive for diatomic molecules in which both atoms are the same element. An international team of scientists from the University of Frankfurt in Germany, Berkeley Lab, Kansas State University, and Auburn University has now resolved the issue with an appropriate twist of quantum fuzziness. By means of coincident detection of the photoelectron ejected from molecular nitrogen and the Auger electron emitted femtoseconds later, the team found that how the measurements are done determines which description-localized or delocalized-is valid.

295

Stellar black holes and the origin of cosmic acceleration  

Science Journals Connector (OSTI)

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

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

2009-08-18T23:59:59.000Z

296

Black Hole Motion as Catalyst of Orbital Resonances  

E-Print Network [OSTI]

The motion of a black hole about the centre of gravity of its host galaxy induces a strong response from the surrounding stellar population. We treat the case of a harmonic potential analytically and show that half of the stars on circular orbits in that potential shift to an orbit of lower energy, while the other half receive a positive boost and recede to a larger radius. The black hole itself remains on an orbit of fixed amplitude and merely acts as a catalyst for the evolution of the stellar energy distribution function f(E). We show that this effect is operative out to a radius of approx 3 to 4 times the hole's influence radius, R_bh. We use numerical integration to explore more fully the response of a stellar distribution to black hole motion. We consider orbits in a logarithmic potential and compare the response of stars on circular orbits, to the situation of a `warm' and `hot' (isotropic) stellar velocity field. While features seen in density maps are now wiped out, the kinematic signature of black hole motion still imprints the stellar line-of-sight mean velocity to a magnitude ~18% the local root mean-square velocity dispersion sigma.

C. M. Boily; T. Padmanabhan; A. Paiement

2007-05-18T23:59:59.000Z

297

Curing black hole singularities with local scale invariance  

E-Print Network [OSTI]

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.

Predrag Dominis Prester

2014-02-27T23:59:59.000Z

298

Microhole Coiled Tubing Bottom Hole Assemblies  

SciTech Connect (OSTI)

The original objective of the project, to deliver an integrated 3 1/8-inch diameter Measurement While Drilling (MWD) and Logging While Drilling (LWD) system for drilling small boreholes using coiled tubing drilling, has been achieved. Two prototype systems have been assembled and tested in the lab. One of the systems has been successfully tested downhole in a conventional rotary drilling environment. Development of the 3 1/8-inch system has also lead to development and commercialization of a slightly larger 3.5-inch diameter system. We are presently filling customer orders for the 3.5-inch system while continuing with commercialization of the 3 1/8-inch system. The equipment developed by this project will be offered for sale to multiple service providers around the world, enabling the more rapid expansion of both coiled tubing drilling and conventional small diameter drilling. The project was based on the reuse of existing technology whenever possible in order to minimize development costs, time, and risks. The project was begun initially by Ultima Labs, at the time a small company ({approx}12 employees) which had successfully developed a number of products for larger oil well service companies. In September, 2006, approximately 20 months after inception of the project, Ultima Labs was acquired by Sondex plc, a worldwide manufacturer of downhole instrumentation for cased hole and drilling applications. The acquisition provided access to proven technology for mud pulse telemetry, downhole directional and natural gamma ray measurements, and surface data acquisition and processing, as well as a global sales and support network. The acquisition accelerated commercialization through existing Sondex customers. Customer demand resulted in changes to the product specification to support hotter (150 C) and deeper drilling (20,000 psi pressure) than originally proposed. The Sondex acquisition resulted in some project delays as the resistivity collar was interfaced to a different MWD system and also as the mechanical design was revised for the new pressure requirements. However, the Sondex acquisition has resulted in a more robust system, secure funding for completion of the project, and more rapid commercialization.

Don Macune

2008-06-30T23:59:59.000Z

299

General relativistic simulations of black-hole-neutron-star mergers: Effects of black-hole spin  

SciTech Connect (OSTI)

Black-hole-neutron-star (BHNS) binary mergers are candidate engines for generating both short-hard gamma-ray bursts and detectable gravitational waves. Using our most recent conformal thin-sandwich BHNS initial data and our fully general relativistic hydrodynamics code, which is now adaptive mesh refinement capable, we are able to efficiently and accurately simulate these binaries from large separations through inspiral, merger, and ringdown. We evolve the metric using the Baumgarte-Shapiro-Shibata-Nakamura formulation with the standard moving puncture gauge conditions, and handle the hydrodynamics with a high-resolution shock-capturing scheme. We explore the effects of BH spin (aligned and antialigned with the orbital angular momentum) by evolving three sets of initial data with BH:NS mass ratio q=3: the data sets are nearly identical, except the BH spin is varied between a/M{sub BH}=-0.5 (antialigned), 0.0, and 0.75. The number of orbits before merger increases with a/M{sub BH}, as expected. We also study the nonspinning BH case in more detail, varying q between 1, 3, and 5. We calculate gravitational waveforms for the cases we simulate and compare them to binary black-hole waveforms. Only a small disk (<0.01M{sub {center_dot}}) forms for the antialigned spin case (a/M{sub BH}=-0.5) and for the most extreme-mass-ratio case (q=5). By contrast, a massive (M{sub disk}{approx_equal}0.2M{sub {center_dot}}) hot disk forms in the rapidly spinning (a/M{sub BH}=0.75) aligned BH case. Such a disk could drive a short-hard gamma-ray burst, possibly by, e.g., producing a copious flux of neutrino-antineutrino pairs.

Etienne, Zachariah B.; Liu, Yuk Tung; Shapiro, Stuart L. [Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States); Baumgarte, Thomas W. [Department of Physics and Astronomy, Bowdoin College, Brunswick, Maine 04011 (United States)

2009-02-15T23:59:59.000Z

300

T-623: HP Business Availability Center Input Validation Hole Permits  

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

3: HP Business Availability Center Input Validation Hole 3: HP Business Availability Center Input Validation Hole Permits Cross-Site Scripting Attacks T-623: HP Business Availability Center Input Validation Hole Permits Cross-Site Scripting Attacks May 16, 2011 - 3:05pm Addthis PROBLEM: A vulnerability was reported in HP Business Availability Center. A remote user can conduct cross-site scripting attacks. PLATFORM: HP Business Availability Center software 8.06 and prior versions ABSTRACT: The software does not properly filter HTML code from user-supplied input before displaying the input. reference LINKS: SecurityTracker Alert ID:1025535 HP Knowledge Base CVE-2011-1856 Secunia ID: SA44569 HP Document ID:c02823184 | ESB-2011.0525 IMPACT ASSESSMENT: High Discussion: A remote user can cause arbitrary scripting code to be executed by the

Note: This page contains sample records for the topic "hydroprobe slim holes" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Seven Mile Hole Geothermal Area | Open Energy Information  

Open Energy Info (EERE)

form form View source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit with form History Facebook icon Twitter icon » Seven Mile Hole Geothermal Area (Redirected from Seven Mile Hole Area) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Geothermal Resource Area: Seven Mile Hole Geothermal Area Contents 1 Area Overview 2 History and Infrastructure 3 Regulatory and Environmental Issues 4 Exploration History 5 Well Field Description 6 Geology of the Area 7 Geofluid Geochemistry 8 NEPA-Related Analyses (0) 9 Exploration Activities (4) 10 References Area Overview Geothermal Area Profile Location: Wyoming Exploration Region: Yellowstone Caldera Geothermal Region GEA Development Phase:

302

Information consumption by Reissner-Nordstrm black holes  

Science Journals Connector (OSTI)

The low-energy scattering of charged fermions by extremal magnetic Reissner-Nordstrm black holes is analyzed in the large-N and S-wave approximations. It is shown that (in these approximations) information is carried into a causally inaccessible region of spacetime, and thereby effectively lost. It is also shown that there is an infinite degeneracy of quantum black hole ground states, or "remnants," which store, but will not reveal, the information. A notable feature of the analysis, not shared by recent analyses of dilatonic black holes, is that the key physical questions can be answered within the weak coupling domain. We regard these results as strong evidence that effective information loss occurs in our Universe.

Andrew Strominger and Sandip P. Trivedi

1993-12-15T23:59:59.000Z

303

Massive Black Hole Science with eLISA  

E-Print Network [OSTI]

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.

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

2015-01-09T23:59:59.000Z

304

Regular Black Hole Metric with Three Constants of Motion  

E-Print Network [OSTI]

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 ...

Johannsen, Tim

2015-01-01T23:59:59.000Z

305

Modeling feedback from stars and black holes in galaxy mergers  

E-Print Network [OSTI]

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...

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

2004-01-01T23:59:59.000Z

306

Black/White hole radiation from dispersive theories  

E-Print Network [OSTI]

We study the fluxes emitted by black holes when using dispersive field theories. We work with stationary one dimensional backgrounds which are asymptotically flat on both sides of the horizon. The asymptotic fluxes are governed by a 3x3 Bogoliubov transformation. The fluxes emitted by the corresponding white holes are regular and governed by the inverse transformation. We numerically compute the spectral properties of these fluxes for both sub- and superluminal quartic dispersion. The leading deviations with respect to the dispersionless flux are computed and shown to be governed by a critical frequency above which there is no radiation. Unlike the UV scale governing dispersion, its value critically depends on the asymptotic properties of the background. We also study the flux outside the robust regime. In particular we show that its low frequency part remains almost thermal but with a temperature which significantly differs from the standard one. Application to four dimensional black holes and Bose-Einstein condensates are in preparation.

Jean Macher; Renaud Parentani

2009-06-02T23:59:59.000Z

307

Cloud of strings for radiating black holes in Lovelock gravity  

E-Print Network [OSTI]

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.

Sushant G. Ghosh; Sunil D. Maharaj

2014-09-28T23:59:59.000Z

308

Black Holes, Entropies, and Semiclassical Spacetime in Quantum Gravity  

E-Print Network [OSTI]

We present a coherent picture of the quantum mechanics of black holes. The picture does not require the introduction of any drastically new physical effect beyond what is already known; it arises mostly from synthesizing and (re)interpreting existing results in appropriate manners. We identify the Bekenstein-Hawking entropy as the entropy associated with coarse-graining performed to obtain semiclassical field theory from a fundamental microscopic theory of quantum gravity. This clarifies the issues around the unitary evolution, the existence of the interior spacetime, and the thermodynamic nature in black hole physics--any result in semiclassical field theory is a statement about the maximally mixed ensemble of microscopic quantum states consistent with the specified background, within the precision allowed by quantum mechanics. We present a detailed analysis of information transfer in Hawking emission and black hole mining processes, clarifying what aspects of the underlying dynamics are (not) visible in sem...

Nomura, Yasunori

2014-01-01T23:59:59.000Z

309

The Schwarzschild black hole as a gravitational mirror  

Science Journals Connector (OSTI)

The gravitational field outside of a nonrotating black hole is described using the Schwarzschild metric. The geodesic equations of the Schwarzschild metric are derived and those describing null and circular timelike orbits are discussed. Some numerical solutions of the null geodesic equations are shown. These depict photon trajectories which circle the black hole one or two times and then terminate at their emission points. Thus a sequence of ring?shaped mirror images is produced. An equation which gives the angle between the photons trajectory and the radial direction at the emitter is derived and applied to the numerical solutions. These results serve to illustrate how an observer passes through his or her mirror image at r=3 MG/c 2 as he or she moves toward a Schwarzschild black hole.

W. M. Stuckey

1993-01-01T23:59:59.000Z

310

Thermodynamic critical and geometrical properties of charged BTZ black hole  

SciTech Connect (OSTI)

The heat capacities and the electric capacitances of charged Banados-Teitelboim-Zanelli (BTZ) black hole are first calculated. By using the equilibrium fluctuation theory of thermodynamics the second-order moments in three different ensembles are obtained, and it is found that in the microcanonical ensemble the extremal charged BTZ black hole is a critical point of the second-order phase transition. The critical exponents associated with some response coefficients satisfy the scaling law of the first kind and the effective spatial dimension is determined to be one from the scaling law of the second kind. The Ricci curvature scalar associated with the Ruppeiner thermodynamic metric is calculated, which suggests also that the effective spatial dimension of the charged BTZ black hole is one.

Wei Yihuan [Department of Physics, Bohai University, Jinzhou 121000, Liaoning (China)

2009-07-15T23:59:59.000Z

311

Thermal stress on bottom hole rock of gas drilling  

Science Journals Connector (OSTI)

Gas drilling has higher penetration than mud drilling. The greatest reason for this phenomenon with gas is that the gas is greatly cooled by expansion as it passes through the bit and thereby cools the bottom of the hole. The thermal stress at bottom-hole occurs during this process. The concept of thermal crushing of rocks is analysed in this study. The theoretical methods are developed to analyse thermal stresses and fragmentation induced by cooling of rock. Then, the numerical computation is conducted for the thermal stress equations with the numerical result simulated for the temperature field at the bottom hole to explain the reason of high drilling rates in gas drilling. Furthermore, an experiment was conducted to verify the theory. Therefore, the theories and simulated results in this paper have a guiding signification for best understand the technique and possibly to extend its economic advantage still further. [Received: September 23, 2011; Accepted: November 20, 2011

Shunji Yang; Gonghui Liu; Jun Li

2012-01-01T23:59:59.000Z

312

Seven Mile Hole Geothermal Area | Open Energy Information  

Open Energy Info (EERE)

Seven Mile Hole Geothermal Area Seven Mile Hole Geothermal Area Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Geothermal Resource Area: Seven Mile Hole Geothermal Area Contents 1 Area Overview 2 History and Infrastructure 3 Regulatory and Environmental Issues 4 Exploration History 5 Well Field Description 6 Geology of the Area 7 Geofluid Geochemistry 8 NEPA-Related Analyses (0) 9 Exploration Activities (4) 10 References Area Overview Geothermal Area Profile Location: Wyoming Exploration Region: Yellowstone Caldera Geothermal Region GEA Development Phase: 2008 USGS Resource Estimate Mean Reservoir Temp: Estimated Reservoir Volume: Mean Capacity: Click "Edit With Form" above to add content History and Infrastructure Operating Power Plants: 0 No geothermal plants listed. Add a new Operating Power Plant

313

Advection-Dominated Accretion and the Black Hole Event Horizon  

E-Print Network [OSTI]

As the luminosity of an accreting black hole drops to a few percent of Eddington, the spectrum switches from the familiar soft state to a hard state that is well-described by a distended and tenuous advection-dominated accretion flow (ADAF). An ADAF is a poor radiator, and the ion temperature can approach 10^{12} K near the center, although the electrons are cooler, with their temperature typically capped at ~10^{9-11} K. The foundational papers predicted that the large thermal energy in an ADAF would drive strong winds and jets, as later observed and also confirmed in computer simulations. Of chief interest, however, is the accreting gas that races inward. It carries the bulk of the accretion energy as stored thermal energy, which vanishes without a trace as the gas passes through the hole's event horizon. One thus expects black holes in the ADAF regime to be unusually faint. Indeed, this is confirmed by a comparison of accreting stellar-mass black holes and neutron stars, which reside in very similar transient X-ray binary systems. The black holes are on average observed to be fainter by a factor of ~100-1000. The natural explanation is that a neutron star must radiate the advected thermal energy from its surface, whereas a black hole can hide the energy behind its event horizon. The case for an event horizon in Sagittarius A*, which is immune to caveats on jet outflows and is furthermore independent of the ADAF model, is especially compelling. These two lines of evidence for event horizons are impervious to counterarguments that invoke strong gravity or exotic stars.

Ramesh Narayan; Jeffrey E. McClintock

2008-03-03T23:59:59.000Z

314

Final Report Limited Soil Investigation of Project Chariot Test Holes  

Office of Legacy Management (LM)

Limited Soil Investigation of Project Limited Soil Investigation of Project Chariot Test Holes Cape Thompson, Alaska December 2010 Prepared for U.S. Department of Energy and U.S. Army Corps of Engineers, Alaska District Post Office Box 6898 Elmendorf AFB, Alaska 99506-6898 Contract W911KB-08-D-0003 Task Order 12, Mod 001 Prepared by Fairbanks Environmental Services 3538 International Street Fairbanks, Alaska 99701 (907) 452-1006 FES Project No. 5012-06 Final Report Limited Soil Investigation of Project Chariot Test Holes, Cape Thompson, Alaska Fairbanks Environmental Services 5012-06 TABLE OF CONTENTS Page Number EXECUTIVE SUMMARY 1.0 INTRODUCTION ................................................................................................... 1-1

315

Automatic CNC Part Programming for through Hole Drilling  

Science Journals Connector (OSTI)

Abstract This paper describes a novel method for automatic generation of process plans and numerical control (NC) part programs from STEP data files. Using proposed system, it is possible to achieve fully automation of recognition of through hole features, generation of process plans and NC part programs. Thus, it becomes possible to go from neutral file to finished product in a fully automated fashion. The algorithms have been implemented on mini-computer to process product data, and display recognized hole features, process plans and creates output files containing NC part programs. These NC part programs are tested through BMV45TC24 CNC Vertical Machining Centers. The results are satisfactory.

B.R. Borkar; Y.M. Puri; A.M. Kuthe; P.S. Deshpande

2014-01-01T23:59:59.000Z

316

Exploring higher dimensional black holes at the large hadron collider.  

E-Print Network [OSTI]

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...

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

317

Repairs for damaged bolt holes in continuous fiber reinforced plastics  

E-Print Network [OSTI]

repair method for damaged bolt holes in such composites. Bolt holes in three types of graphite-epoxy were purposely damaged and then repaired. Each was tested to characterize its static and fatigue behavior. The tests used a special fixture to simulate... composite joints . Bearing-bypass ratio can change the failure mode of bolted composite joints 7 Drilling defects in graphite-epoxy coupons 12 26 The exit side of a IM7/8551-7A 18 ply tape coupon showing the damage due to drilling 27 9 Resin filled...

Copps, Kevin Daniel

2012-06-07T23:59:59.000Z

318

A Commentary on Ruppeiner Metrics for Black Holes  

E-Print Network [OSTI]

There has been some recent controversy regarding the Ruppeiner metrics that are induced by Reissner-Nordstrom (and Reissner-Nordstrom-like) black holes. Most infamously, why does this family of metrics turn out to be flat, how is this outcome to be physically understood, and can/should the formalism be suitably modified to induce curvature? In the current paper, we provide a novel interpretation of this debate. For the sake of maximal analytic clarity and tractability, some supporting calculations are carried out for the relatively simple model of a rotating BTZ black hole.

A. J. M. Medved

2008-01-23T23:59:59.000Z

319

Semiclassical decay of near-extremal black holes  

Science Journals Connector (OSTI)

The 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.

Ted Jacobson

1998-04-15T23:59:59.000Z

320

Black hole entanglement entropy and the renormalization group  

Science Journals Connector (OSTI)

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.

Ted Jacobson and Alejandro Satz

2013-04-18T23:59:59.000Z

Note: This page contains sample records for the topic "hydroprobe slim holes" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Dirac monopoles on Kerr black holes: comparing gauges  

E-Print Network [OSTI]

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.

Yu. P. Goncharov

1998-11-17T23:59:59.000Z

322

Black hole entanglement entropy and the renormalization group  

E-Print Network [OSTI]

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.

Ted Jacobson; Alejandro Satz

2013-03-21T23:59:59.000Z

323

Black holes and black strings in plane waves  

E-Print Network [OSTI]

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.

Julian Le Witt; Simon F. Ross

2009-10-30T23:59:59.000Z

324

Using the uncharged Kerr black hole as a gravitational mirror  

E-Print Network [OSTI]

We extend the study of the possibility to use the Schwarzschild black hole as a gravitational mirror to the more general case of an uncharged Kerr black hole. We use the null geodesic equation in the equatorial plane to prove a theorem concerning the conditions the impact parameter has to satisfy if there shall exist boomerang photons. We derive an equation for these boomerang photons and an equation for the emission angle. Finally, the radial null geodesic equation is integrated numerically in order to illustrate boomerang photons.

Cramer, C R

1995-01-01T23:59:59.000Z

325

Using the Uncharged Kerr Black Hole as a Gravitational Mirror  

E-Print Network [OSTI]

We extend the study of the possibility to use the Schwarzschild black hole as a gravitational mirror to the more general case of an uncharged Kerr black hole. We use the null geodesic equation in the equatorial plane to prove a theorem concerning the conditions the impact parameter has to satisfy if there shall exist boomerang photons. We derive an equation for these boomerang photons and an equation for the emission angle. Finally, the radial null geodesic equation is integrated numerically in order to illustrate boomerang photons.

Claes R Cramer

1995-10-25T23:59:59.000Z

326

Stationary black-hole binaries: A non-existence proof  

E-Print Network [OSTI]

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.

Gernot Neugebauer; Jrg Hennig

2014-06-23T23:59:59.000Z

327

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

E-Print Network [OSTI]

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 ...

Zucker, Michael E.

328

Geology of Geothermal Test Hole GT-2 Fenton Hill Site, July 1974...  

Open Energy Info (EERE)

Test Hole GT-2 Fenton Hill Site, July 1974 Jump to: navigation, search OpenEI Reference LibraryAdd to library Report: Geology of Geothermal Test Hole GT-2 Fenton Hill Site, July...

329

MEMS Materials and Temperature Sensors for Down Hole Geothermal System Monitoring  

E-Print Network [OSTI]

Geothermal EnergyThe future of geothermal energy: Impact of enhanceddown-hole monitoring of geothermal energy systems. ASME 2011

Wodin-Schwartz, Sarah

2013-01-01T23:59:59.000Z

330

The relation between Hawking radiation via tunnelling and the laws of black hole thermodynamics  

E-Print Network [OSTI]

In Parikh and Wilczek's original works, the laws of black hole thermodynamics are not referred and it seems that there is no relation between Hawking radiation via tunnelling and the laws of black hole thermodynamics in their works. However, taking examples for the R-N black hole and the Kerr black hole, we find that they are correlated and even consistent if the tunnelling process is a reversible process.

Yapeng Hu; Jingyi Zhang; Zheng Zhao

2006-01-05T23:59:59.000Z

331

Process and structures for fabrication of solar cells with laser ablation steps to form contact holes  

DOE Patents [OSTI]

Contact holes of solar cells are formed by laser ablation to accomodate various solar cell designs. Use of a laser to form the contact holes is facilitated by replacing films formed on the diffusion regions with a film that has substantially uniform thickness. Contact holes may be formed to deep diffusion regions to increase the laser ablation process margins. The laser configuration may be tailored to form contact holes through dielectric films of varying thickness.

Harley, Gabriel; Smith, David D; Dennis, Tim; Waldhauer, Ann; Kim, Taeseok; Cousins, Peter John

2013-11-19T23:59:59.000Z

332

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

333

Absorption of planar massless scalar waves by Bardeen regular black holes  

E-Print Network [OSTI]

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.

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

2014-08-08T23:59:59.000Z

334

Ultrafast Core-Hole Induced Dynamics in Water  

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

Ultrafast Core-Hole Induced Ultrafast Core-Hole Induced Dynamics in Water Ultrafast Core-Hole Induced Dynamics in Water Print Wednesday, 22 February 2006 00:00 A thorough understanding of the chemical processes that are initiated when radiation interacts with aqueous systems is essential for many diverse fields, from condensed matter physics to medicine to environmental science. An incoming photon with enough energy to produce a core hole in a water molecule sets off motions that can affect bonding configurations, which in turn affect subsequent chemical-reaction pathways. However, it is a fundamental challenge for the radiation chemistry community to unravel the early time dynamics of electronically excited states in water because their short (femtosecond) time scales are difficult to access directly with pump-probe measurements. Using a combination of isotope substitution experiments and molecular dynamics simulations, researchers from Sweden, Germany, and the U.S. have shown that the ultrafast (0- to 10-fs) dissociation dynamics of liquid water can be successfully probed with x-ray emission spectroscopy.

335

Primordial black holes from temporally enhanced curvature perturbation  

E-Print Network [OSTI]

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.

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

2014-06-02T23:59:59.000Z

336

Hole Selective MoOx Contact for Silicon Solar Cells  

Science Journals Connector (OSTI)

Hole Selective MoOx Contact for Silicon Solar Cells ... This work has important implications toward enabling a novel class of junctionless devices with applications for solar cells, light-emitting diodes, photodetectors, and transistors. ... Junctionless solar cells; silicon photovoltaics; heterojunctions; dopant-free contact; molybdenum trioxide ...

Corsin Battaglia; Xingtian Yin; Maxwell Zheng; Ian D. Sharp; Teresa Chen; Stephen McDonnell; Angelica Azcatl; Carlo Carraro; Biwu Ma; Roya Maboudian; Robert. M. Wallace; Ali Javey

2014-01-07T23:59:59.000Z

337

Even-Hole-Free Graphs Part II: Recognition Algorithm  

E-Print Network [OSTI]

of Computer Studies, University of Leeds, Leeds LS29JT, United Kingdom. This work was supported in part by NSF, University of Waterloo on an NSERC Canada International Fellowship. Ajai Kapoor was supported by a grant from recognition algorithm for even-hole-free graphs. The algorithm builds on a structural theorem proved in [4

Cornuejols, Gerard P.

338

THE FORMATION AND EVOLUTION OF THE FIRST MASSIVE BLACK HOLES  

E-Print Network [OSTI]

@astron.berkeley.edu Abstract The first massive astrophysical black holes likely formed at high redshifts (z > 10 (Eddington) luminosity, and converts mass to radiation with an efficiency of = Mc2 /LEdd 10%) and using to link the evolution of quasars with that of dark matter halos condensing in a cold dark matter (CDM

Wurtele, Jonathan

339

Weak field limit of Reissner-Nordstrm black hole lensing  

Science Journals Connector (OSTI)

We study gravitational lensing by a Reissner-Nordstrm black hole in the weak field limit. We obtain the basic equations for the deflection angle and time delay and find analytical expressions for the positions and amplifications of the primary and secondary images. Because of a net positive charge, the separation between images increases, but no change in the total magnification occurs.

Mauro Sereno

2004-01-13T23:59:59.000Z

340

Multi-modal transmission of microwaves through hole arrays  

E-Print Network [OSTI]

. R. Evans, and J. R. Sambles, "Experimental verification of designer surface plasmons," Science 308Multi-modal transmission of microwaves through hole arrays James D. Edmunds,1,* Euan Hendry,1(5722), 670­672 (2005). 8. S. A. Maier, S. R. Andrews, L. Martín-Moreno, and F. J. García-Vidal, "Terahertz

Exeter, University of

Note: This page contains sample records for the topic "hydroprobe slim holes" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Tips for implementing multigrid methods on domains containing holes  

E-Print Network [OSTI]

As part of our development of a computer code to perform 3D `constrained evolution' of Einstein's equations in 3+1 form, we discuss issues regarding the efficient solution of elliptic equations on domains containing holes (i.e., excised regions), via the multigrid method. We consider as a test case the Poisson equation with a nonlinear term added, as a means of illustrating the principles involved, and move to a "real world" 3-dimensional problem which is the solution of the conformally flat Hamiltonian constraint with Dirichlet and Robin boundary conditions. Using our vertex-centered multigrid code, we demonstrate globally second-order-accurate solutions of elliptic equations over domains containing holes, in two and three spatial dimensions. Keys to the success of this method are the choice of the restriction operator near the holes and definition of the location of the inner boundary. In some cases (e.g. two holes in two dimensions), more and more smoothing may be required as the mesh spacing decreases to zero; however for the resolutions currently of interest to many numerical relativists, it is feasible to maintain second order convergence by concentrating smoothing (spatially) where it is needed most. This paper, and our publicly available source code, are intended to serve as semi-pedagogical guides for those who may wish to implement similar schemes.

Scott H. Hawley; Richard A. Matzner

2003-11-18T23:59:59.000Z

342

Characterizing spinning black hole binaries in eccentric orbits with LISA  

SciTech Connect (OSTI)

The Laser Interferometer Space Antenna (LISA) is designed to detect gravitational wave signals from astrophysical sources, including those from coalescing binary systems of compact objects such as black holes. Colliding galaxies have central black holes that sink to the center of the merged galaxy and begin to orbit one another and emit gravitational waves. Some galaxy evolution models predict that the binary black hole system will enter the LISA band with significant orbital eccentricity, while other models suggest that the orbits will already have circularized. Using a full 17 parameter waveform model that includes the effects of orbital eccentricity, spin precession, and higher harmonics, we investigate how well the source parameters can be inferred from simulated LISA data. Defining the reference eccentricity as the value one year before merger, we find that for typical LISA sources, it will be possible to measure the eccentricity to an accuracy of parts in a thousand. The accuracy with which the eccentricity can be measured depends only very weakly on the eccentricity, making it possible to distinguish circular orbits from those with very small eccentricities. LISA measurements of the orbital eccentricity can help constraints theories of galaxy mergers in the early universe. Failing to account for the eccentricity in the waveform modeling can lead to a loss of signal power and bias the estimation of parameters such as the black hole masses and spins.

Key, Joey Shapiro; Cornish, Neil J. [Department of Physics, Montana State University, Bozeman, Montana 59717 (United States)

2011-04-15T23:59:59.000Z

343

Bulk emission of scalars by a rotating black hole  

E-Print Network [OSTI]

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.

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

2008-07-17T23:59:59.000Z

344

Anti-de Sitter black holes in supergravity  

E-Print Network [OSTI]

equal. In five dimensions, the most general charged rotating black hole solution has three charge and two rotation parameters. We obtain several special cases of the general solution. To be specific, we obtain the first example of a non-extremal rotating...

Chong, Zhiwei

2009-06-02T23:59:59.000Z

345

Measuring the Black Hole Spin in Sgr A*  

E-Print Network [OSTI]

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 minhole (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 $\

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

2001-05-11T23:59:59.000Z

346

Information-theoretic corrections to black hole area quantisation?  

E-Print Network [OSTI]

Nonlinear corrections are proposed to the discrete equispaced area spectrum of quantum black holes obtained previously in some quantisation schemes. It is speculated that such a modified spectrum might be related to the fine structure found using the loop quantum gravity approach.

Rajesh R Parwani

2009-04-24T23:59:59.000Z

347

The cosmological evolution of quasar black hole masses  

Science Journals Connector (OSTI)

......distribution of the central engine (e.g. Laor 1998, 2000...some other physical limit on fuel supply which prevents accretion...physical limit on black hole fuel supply might be imposed by...expected to limit the mass consumption rate of a supermassive black......

Ross J. McLure; James S. Dunlop

2004-08-21T23:59:59.000Z

348

Increase of Black Hole Entropy in Higher Curvature Gravity  

E-Print Network [OSTI]

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.

Ted Jacobson; Gungwon Kang; Robert C. Myers

1995-03-11T23:59:59.000Z

349

Reissner-Nordstrom black hole in dark energy background  

E-Print Network [OSTI]

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.

Ngangbam Ishwarchandra; Ng. Ibohal; K. Yugindro Singh

2014-11-29T23:59:59.000Z

350

Black Holes, Firewalls and Chaos from Gravitational Collapse  

E-Print Network [OSTI]

One of the most spectacular predictions of the general theory of relativity is the black hole, an object that plays a central role in modern physics [1,2,3] and astrophysics [4,5]. Black holes are, however, plagued by fundamental paradoxes that remain unresolved to this day. First, the black hole event horizon is teleological in nature [6], which means that we need to know the entire future space-time of the universe to determine the current location of the horizon. This is essentially impossible. Second, any information carried by infalling matter is lost once the material falls through the event horizon. Even though the black hole may later evaporate by emitting Hawking radiation [7], the lost information does not reappear, which has the rather serious and disturbing consequence that quantum unitarity is violated [8]. Here we propose that the above paradoxes are restricted to a particular idealized model of collapse first studied in the 1930s [9, 10] in which the event horizon, which defines the boundary of...

Joshi, Pankaj S

2014-01-01T23:59:59.000Z

351

Big-hole drilling - the state of the art  

SciTech Connect (OSTI)

The art of big-hole drilling has been in a continual state of evolution at the Nevada Test Site since the start of underground testing in 1961. Emplacement holes for nuclear devices are still being drilled by the rotary-drilling process, but almost all the hardware and systems have undergone many changes during the intervening years. The current design of bits, cutters, and other big-hole-drilling hardware results from contributions of manufacturers and Test Site personnel. The dual-string, air-lift, reverse-circulation system was developed at the Test Site. Necessity was really the Mother of this invention, but this circulation system is worthy of consideration under almost any condition. Drill rigs for big-hole drilling are usually adaptations of large oil-well drill rigs with minor modifications required to handle the big bits and drilling assemblies. Steel remains the favorite shaft lining material, but a lot of thought is being given to concrete linings, especially precast concrete.

Lackey, M.D.

1983-01-01T23:59:59.000Z

352

The Formation and Evolution of Massive Black Holes  

Science Journals Connector (OSTI)

...electromagnetic spectrum, as well as Chandra, X-ray Multi-Mirror MissionNewton, Swift, and Fermi at higher energies...volumes to isolated galaxies, to accretion discs down to a few Schwarzschild radii in black hole merger simulations in general relativity...

M. Volonteri

2012-08-03T23:59:59.000Z

353

Gauss-Bonnet black holes with nonconstant curvature horizons  

SciTech Connect (OSTI)

We investigate static and dynamical n({>=}6)-dimensional black holes in Einstein-Gauss-Bonnet gravity of which horizons have the isometries of an (n-2)-dimensional Einstein space with a condition on its Weyl tensor originally given by Dotti and Gleiser. Defining a generalized Misner-Sharp quasilocal mass that satisfies the unified first law, we show that most of the properties of the quasilocal mass and the trapping horizon are shared with the case with horizons of constant curvature. It is shown that the Dotti-Gleiser solution is the unique vacuum solution if the warp factor on the (n-2)-dimensional Einstein space is nonconstant. The quasilocal mass becomes constant for the Dotti-Gleiser black hole and satisfies the first law of the black-hole thermodynamics with its Wald entropy. In the non-negative curvature case with positive Gauss-Bonnet constant and zero cosmological constant, it is shown that the Dotti-Gleiser black hole is thermodynamically unstable. Even if it becomes locally stable for the nonzero cosmological constant, it cannot be globally stable for the positive cosmological constant.

Maeda, Hideki [Centro de Estudios Cientificos (CECS), Casilla 1469, Valdivia (Chile)

2010-06-15T23:59:59.000Z

354

Conserved Charges and Thermodynamics of the Spinning Goedel Black Hole  

SciTech Connect (OSTI)

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.

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

355

Vibrating Black Holes in f(R) gravity  

E-Print Network [OSTI]

We consider general perturbations of a Schwarzschild black holes in the context of f(R) gravity. A reduced set of frame independent master variables are determined, which obey two closed wave equations - one for the transverse, trace-free (tensor) perturbations and the other for the additional scalar degree of freedom which characterise fourth-order theories of gravity. We show that for the tensor modes, the underlying dynamics in f(R) gravity is governed by a modified Regge-Wheeler tensor which obeys the same Regge-Wheeler equation as in General Relativity. We find that the possible sources of scalar quasinormal modes that follow from scalar perturbations for the lower multipoles result from primordial black holes, while higher mass, stellar black holes are associated with extremely high multipoles, which can only be produced in the first stage of black hole formation. Since scalar quasi-normal modes are short ranged, this scenario makes their detection beyond the range of current experiments.

Anne Marie Nzioki; Rituparno Goswami; Peter K. S. Dunsby

2014-08-01T23:59:59.000Z

356

Probing Alpha-Vacua of Black Holes in LHC  

E-Print Network [OSTI]

Motivated by the idea of alpha-vacua in Schwarzschild spacetime, we studied the deformed spectrum of Hawking radiation. Such a deformation would leave signatures on the small black hole evaporation in LHC because their vacuum deviates from the Unruh state.

Tower Wang

2007-04-18T23:59:59.000Z

357

No black holes, but extra time at LHC  

Science Journals Connector (OSTI)

... , microscopic black holes have so far failed to appear inside the Large Hadron Collider (LHC), scientists there have revealed. The result, which will be posted this week on ... be posted this week on arXiv.org, comes as researchers make plans to keep the LHC running until the end of 2012, rather than 2011 as previously scheduled. The 27 ...

Geoff Brumfiel

2010-12-14T23:59:59.000Z

358

A Mechanism for Detecting Gray Hole Attacks on Synchrophasor Data  

E-Print Network [OSTI]

in smart grids [1]. Phasor measurement unit (PMU) or synchrophasor data serves to facilitate a number. This paper addresses the problem of securing PMU data against packet dropping or gray hole attacks in the network on PMU data can easily lead to the loss of observability of the system and render useless a number

Sikdar, Biplab

359

The Inside Story: Quasilocal Tachyons and Black Holes  

SciTech Connect (OSTI)

We analyze the fate of excitations in regions of closed string tachyon condensate, a question crucial for understanding unitarity in a class of black holes in string theory. First we introduce a simple new example of quasilocal tachyon condensation in a globally stable AdS/CFT background, and review tachyons' appearance in black hole physics. Then we calculate forces on particles and fields in a tachyon phase using a field theoretic model with spatially localized exponentially growing time dependent masses. This model reveals two features, both supporting unitary evolution in the bulk of spacetime. First, the growing energy of fields sourced by sets of (real and virtual) particles in the tachyon phase yields outward forces on them, leaving behind only combinations which do not source any fields. Secondly, requiring the consistency of perturbative string theory imposes cancellation of a BRST anomaly, which also yields a restricted set of states. Each of these effects supports the notion of a black hole final state arising from string-theoretic dynamics replacing the black hole singularity.

Horowitz, Gary T.; /UC, Santa Barbara; Silverstein, Eva; /SLAC /Stanford U., Phys. Dept.

2006-01-13T23:59:59.000Z

360

Fallback and Black Hole Production in Massive Stars  

SciTech Connect (OSTI)

The compact remnants of core collapse supernovae--neutron stars and black holes--have properties that reflect both the structure of their stellar progenitors and the physics of the explosion. In particular, the masses of these remnants are sensitive to the density structure of the presupernova star and to the explosion energy. To a considerable extent, the final mass is determined by the ''fallback'', during the explosion, of matter that initially moves outwards, yet ultimately fails to escape. We consider here the simulated explosion of a large number of massive stars (10 to 100 M{sub {circle_dot}}) of Population I (solar metallicity) and III (zero metallicity), and find systematic differences in the remnant mass distributions. As pointed out by Chevalier (1989), supernovae in more compact progenitor stars have stronger reverse shocks and experience more fallback. For Population III stars above about 25 M{sub {circle_dot}} and explosion energies less than 1.5 x 10{sup 51} erg, black holes are a common outcome, with masses that increase monotonically with increasing main sequence mass up to a maximum hole mass of about 35 M{sub {circle_dot}}. If such stars produce primary nitrogen, however, their black holes are systematically smaller. For modern supernovae with nearly solar metallicity, black hole production is much less frequent and the typical masses, which depend sensitively on explosion energy, are smaller. We explore the neutron star initial mass function for both populations and, for reasonable assumptions about the initial mass cut of the explosion, find good agreement with the average of observed masses of neutron stars in binaries. We also find evidence for a bimodal distribution of neutron star masses with a spike around 1.2 M{sub {circle_dot}} (gravitational mass) and a broader distribution peaked around 1.4 M{sub {circle_dot}}.

Zhang, Wei-Qun; /KIPAC, Menlo Park; Woosley, S.E.; /UC, Santa Cruz; Heger, A.; /UC, Santa Cruz /Los Alamos

2007-01-08T23:59:59.000Z

Note: This page contains sample records for the topic "hydroprobe slim holes" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

The bremsstrahlung spectrum for the electric dipole which nonradially falls into a black hole  

E-Print Network [OSTI]

The electromagnetic bremsstrahlung spectrum for the dipole which falling by a spiral orbit into the Schwarzschild black hole was found. The characteristic features in this electromagnetic spectrum can be used for determine of the black hole mass by the new way. This new way (if implemented) provides higher accuracy in determining of the black hole mass. Also these features in the spectrum can be used for determine of the certain characteristics in the black hole magnetosphere or in the accretion disk characteristics around the black hole. It is also shown that the asymptotic behavior of this spectrum (at high frequencies) is practically independent from the impact parameter of the falling dipole.

Shatskiy, Alexander; Malinovsky, Alexandr

2015-01-01T23:59:59.000Z

362

Characterizing asymptotically anti-de Sitter black holes with abundant stable gauge field hair  

E-Print Network [OSTI]

In the light of the "no-hair" conjecture, we revisit stable black holes in su(N) Einstein-Yang-Mills theory with a negative cosmological constant. These black holes are endowed with copious amounts of gauge field hair, and we address the question of whether these black holes can be uniquely characterized by their mass and a set of global non-Abelian charges defined far from the black hole. For the su(3) case, we present numerical evidence that stable black hole configurations are fixed by their mass and two non-Abelian charges. For general N, we argue that the mass and N-1 non-Abelian charges are sufficient to characterize large stable black holes, in keeping with the spirit of the "no-hair" conjecture, at least in the limit of very large magnitude cosmological constant and for a subspace containing stable black holes (and possibly some unstable ones as well).

Ben L. Shepherd; Elizabeth Winstanley

2012-02-07T23:59:59.000Z

363

Thermal Gradient Holes At Twenty-Nine Palms Area (Page, Et Al., 2010) |  

Open Energy Info (EERE)

Thermal Gradient Holes At Twenty-Nine Palms Thermal Gradient Holes At Twenty-Nine Palms Geothermal Area (Page, Et Al., 2010) Exploration Activity Details Location Twenty-Nine Palms Geothermal Area Exploration Technique Thermal Gradient Holes Activity Date Usefulness useful DOE-funding Unknown Notes From November 2008 to March 2009, Seabees from the Naval Construction Division (NCD) successfully completed fivetemperature gradient holes for the GPO. Samples taken from each hole were similar in nature; mixtures of sand and conglomerates with the occasional granite sections were typically encountered. Each hole varied slightly in depth, ranging from 600ft to 1,000ft; however, each hole has been completed to acceptable standards of the GPO. Upon completion of drilling, 3" metal tubing was inserted to

364

The black hole in ''bullying at work'' research  

Science Journals Connector (OSTI)

Gathering data about black holes is difficult because we cannot see them. The gravity pull of the black hole is so strong that light, even at its great speed, cannot escape. We know black holes exist only because of celestial bodies around them, which, for example, change course or behave ''oddly'', sometimes being ''eaten'' by the crushing effect of the gravity-pulls from the black hole. For those who study negative behaviour at work, ''the bully'' is the parallel of black holes ?? almost invisible to us. We gain all our data regarding ''bullies'' from other people and events that happen around them. For example, when trying to detect pockets of bullying, personnel are directed to look for high exit rates of staff, long-term sickness due to stress and other side-effects that can be associated with a bullying situation. Finding and studying the bully is like trying to study black holes ?? we are often chasing scattered debris of complex data and shadows of the past. The study reported in this paper used data from subordinates on their managers' behaviour in order to classify how tough the managers were. A spectrum of ''toughness'' of management behaviour was generated. The managers' responses to a variety of measures including stress and mental health were examined as a way of trying to discriminate within the ''toughness'' spectrum. Results were non-significant. The study revealed differences in reporting of negative behaviour of managers and led to the suggestion that three types of manager behaviour might be present. The first is negative behaviour (typical of studies into bullying at work) that causes distress when it is present, but has no positive effect when it is absent ?? for example public humiliation. Another is spectrum behaviour that causes distress when it is absent and is enhancing to subordinates when it is present ?? for example being trusted with information. A third type was suggested as a result of the findings, but not included in this study. This third type could be termed positive behaviour (typical of leadership studies) and be enhancing when it is present, but not cause distress when it is absent ?? for example charismatic leadership. The results are discussed in the light of future research.

Charlotte Rayner; Cary L. Cooper

2003-01-01T23:59:59.000Z

365

Two Electron Holes in Hematite Facilitate Water Splitting  

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

Two Electron Holes in Hematite Facilitate Water Splitting Print Two Electron Holes in Hematite Facilitate Water Splitting Print Hydrogen is an attractive form of fuel because its only by-product is nonpolluting water vapor. The problem, however, is that the production of hydrogen-via the process of water splitting-currently requires the burning of traditional fossil fuels. Therefore, water splitting by photoelectrochemical cells (PECs) fueled by solar power has long been a primary goal of sustainable energy research. One roadblock to this goal is that the search for stable, affordable, high-performance PEC electrodes has so far failed to identify an ideal material. Now, researchers from Switzerland, China, and Berkeley have gained an in-depth understanding of the electronic structure of hematite (iron oxide), a promising PEC photoanode candidate, by performing in situ and operando soft x-ray spectroscopy at ALS Beamline 7.0.1.

366

Two Electron Holes in Hematite Facilitate Water Splitting  

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

Two Electron Holes in Hematite Facilitate Water Splitting Print Two Electron Holes in Hematite Facilitate Water Splitting Print Hydrogen is an attractive form of fuel because its only by-product is nonpolluting water vapor. The problem, however, is that the production of hydrogen-via the process of water splitting-currently requires the burning of traditional fossil fuels. Therefore, water splitting by photoelectrochemical cells (PECs) fueled by solar power has long been a primary goal of sustainable energy research. One roadblock to this goal is that the search for stable, affordable, high-performance PEC electrodes has so far failed to identify an ideal material. Now, researchers from Switzerland, China, and Berkeley have gained an in-depth understanding of the electronic structure of hematite (iron oxide), a promising PEC photoanode candidate, by performing in situ and operando soft x-ray spectroscopy at ALS Beamline 7.0.1.

367

Drilling Large Diameter Holes in Rocks Using Multiple Laser Beams  

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

Drilling Large Diameter Holes in Rocks Using Multiple Laser Beams (504) Drilling Large Diameter Holes in Rocks Using Multiple Laser Beams (504) Richard Parker,. Parker Geoscience Consulting, LLC, Arvada, Colorado, USA; Zhiyue Xu and Claude Reed, Argonne National Laboratory, Argonne, Illinois, USA; Ramona Graves, Department of Petroleum Engineering, Colorado School of Mines, Golden, Colorado, USA; Brian Gahan and Samih Batarseh, Gas Technology Institute, Des Plaines, Illinois, USA ABSTRACT Studies on drilling petroleum reservoir rocks with lasers show that modern infrared lasers have the capability to spall (thermally fragment), melt and vaporize natural earth materials with the thermal spallation being the most efficient rock removal mechanism. Although laser irradiance as low as 1000 W/cm 2 is sufficient to spall rock, firing the

368

Two Electron Holes in Hematite Facilitate Water Splitting  

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

Two Electron Holes in Hematite Facilitate Water Splitting Print Two Electron Holes in Hematite Facilitate Water Splitting Print Hydrogen is an attractive form of fuel because its only by-product is nonpolluting water vapor. The problem, however, is that the production of hydrogen-via the process of water splitting-currently requires the burning of traditional fossil fuels. Therefore, water splitting by photoelectrochemical cells (PECs) fueled by solar power has long been a primary goal of sustainable energy research. One roadblock to this goal is that the search for stable, affordable, high-performance PEC electrodes has so far failed to identify an ideal material. Now, researchers from Switzerland, China, and Berkeley have gained an in-depth understanding of the electronic structure of hematite (iron oxide), a promising PEC photoanode candidate, by performing in situ and operando soft x-ray spectroscopy at ALS Beamline 7.0.1.

369

Woods Hole, Massachusetts: Energy Resources | Open Energy Information  

Open Energy Info (EERE)

Hole, Massachusetts: Energy Resources Hole, Massachusetts: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 41.5264977°, -70.6730857° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":41.5264977,"lon":-70.6730857,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

370

Circularization of Tidally Disrupted Stars around Spinning Supermassive Black Holes  

E-Print Network [OSTI]

We study the circularization of tidally disrupted stars on bound orbits around spinning supermassive black holes by performing three-dimensional smoothed particle hydrodynamic simulations with Post-Newtonian corrections. Our simulations reveal that debris circularization depends sensitively on the efficiency of radiative cooling. There are two stages in debris circularization if radiative cooling is inefficient: first, the stellar debris streams self-intersect due to relativistic apsidal precession; shocks at the intersection points thermalize orbital energy and the debris forms a geometrically thick, ring-like structure around the black hole. The ring rapidly spreads via viscous diffusion, leading to the formation of a geometrically thick accretion disk. In contrast, if radiative cooling is efficient, the stellar debris circularizes due to self-intersection shocks and forms a geometrically thin ring-like structure. In this case, the dissipated energy can be emitted during debris circularization as a precurso...

Hayasaki, Kimitake; Loeb, Abraham

2015-01-01T23:59:59.000Z

371

Instability of black hole formation in gravitational collapse  

SciTech Connect (OSTI)

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

Joshi, Pankaj S.; Malafarina, Daniele [Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005 (India)

2011-01-15T23:59:59.000Z

372

The Matter Plus Black Hole Problem in Axisymmetry  

E-Print Network [OSTI]

We present preliminary results in our long-term project of studying the evolution of matter in a dynamical spacetime. To achieve this, we have developed a new code to evolve axisymmetric initial data sets corresponding to a black hole surrounded by matter fields. The code is based on the coupling of two previously existing codes. The matter fields are evolved with a 2D shock-capturing method which uses the characteristic information of the GR hydro equations to build up a linearized Riemann solver. The spacetime is evolved with a 2D ADM code designed to evolve a wormhole in full general relativity. An example of the kind of problems we are currently investigating is the on axis collision of a star with a black hole.

S. R. Brandt; J. A. Font

1997-11-06T23:59:59.000Z

373

On the origin of the outgoing black hole modes  

Science Journals Connector (OSTI)

The question of how to account for the outgoing black hole modes without drawing upon a trans-Planckian reservoir at the horizon is addressed. It is argued that the outgoing modes must arise via conversion from ingoing modes. It is further argued that the back reaction must be included to avoid the conclusion that particle creation cannot occur in a strictly stationary background. The process of mode conversion is known in plasma physics by this name and in condensed matter physics as Andreev reflection or branch conversion. It is illustrated here in a linear Lorentz noninvariant model introduced by Unruh. The role of interactions and a physical short distance cutoff is then examined in the sonic black hole formed with helium-II. 1996 The American Physical Society.

Ted Jacobson

1996-06-15T23:59:59.000Z

374

Elastic scattering of Dirac fermions on Schwarzschild black holes  

E-Print Network [OSTI]

Approximative analytic solutions of the Dirac equation in the Schwarzschild geometry are used for building the partial wave analysis of Dirac fermions scattered by black holes. The analytic expressions of the differential cross section and induced polarization degree are derived in terms of scattering angle, mass of the black hole, energy and mass of the fermion. We perform a graphical study of differential cross section analysing the forward/backward scattering (known also as glory scattering) and the polarization degree as functions of scattering angle. The graphical analysis shows the presence of oscillations in scattering intensity around forward/backward directions, phenomena known as spiral scattering. The energy dependence of the differential cross section is also established by using analytical and graphical methods.

Ion I. Cotaescu; Cosmin Crucean; Ciprian A. Sporea

2015-02-11T23:59:59.000Z

375

Elastic scattering of Dirac fermions on Schwarzschild black holes  

E-Print Network [OSTI]

Approximative analytic solutions of the Dirac equation in the Schwarzschild geometry are used for building the partial wave analysis of the Dirac fermions scattered by black holes. The analytic expressions of the differential cross section and induced polarization degree are derived in terms of scattering angle, mass of the black-hole, energy and mass of the fermion. We perform a graphical study of differential cross section analysing the forward/backward scattering (known also as glory scattering) and the polarization degree as functions of scattering angle. The graphical analysis shows the presence of oscillations in scattering intensity around forward/backward directions, phenomena known as spiral scattering. In addition, we find that the scattering probability increases significantly for fermions with large angular momentum. The energy dependence of the differential cross section is also established by using analytical and graphical methods.

Ion I. Cotaescu; Cosmin Crucean; Ciprian A. Sporea

2014-10-08T23:59:59.000Z

376

Singularities, geodesics and Green functions in the BTZ black hole  

E-Print Network [OSTI]

In the context of studying black hole singularities by the AdS/CFT correspondence, we study the BTZ black hole by a scalar field propagating on it and the corresponding two-point Green functions. We explore how positions inside the horizon are encoded in the boundary theory. The main idea is to relate two different semi-classical approximations of the Green function and see how this indicates the bulk-boundary correspondence. From a key observation of Festucia and Liu, which is a frequency-geodesic identification, we deduce a geodesic approximation from the saddle point approximation. As an application, we find saddles of the Green function and hence their corresponding geodesics. The conclusion is that some of these geodesics do go inside the horizon. This gives the possibility of resolving the singularity from the boundary theory.

Chen Yang

2006-11-04T23:59:59.000Z

377

Could any black holes be produced at the LHC?  

E-Print Network [OSTI]

We introduce analytical quantum gravity modifications of the production cross section for terascale black holes by employing an effective ultraviolet cut off $l$. We find the new cross sections approach the usual "black disk" form at high energy, while they differ significantly near the fundamental scale from the standard increase with respect to $s$. We show that the heretofore discontinuous step function used to represent the cross section threshold can realistically be modeled by two functions representing the incoming and final parton states in a high energy collision. The growth of the cross section with collision energy is thus a unique signature of $l$ and number of spatial dimensions $d$. Contrary to the classical black disk result, our cross section is able to explain why black holes might not be observable in LHC experiments while they could be still at the reach of ultra-high energy cosmic ray events.

Jonas Mureika; Piero Nicolini; Euro Spallucci

2011-11-24T23:59:59.000Z

378

Unparticle-Enhanced Black Holes at the LHC  

E-Print Network [OSTI]

Based on the idea that tensor unparticles can enhance the gravitational interactions between standard model particles, potential black hole formation in high energy collisions is examined. Modifications to the horizon radius $r_H$ are derived, and the corresponding geometric cross-sections of such objects are calculated. It is shown that $r_H$ increases dramatically to the electroweak scale for masses $M_{BH} \\sim 1-10 $TeV, yielding a geometric cross-section $\\sigma_{BH}=\\pi r_H^2$ on the order of $leq 50$ pb. This suggests that unparticle physics provides a mechanism for black hole formation in future accelerators, without the requirement of extra spatial dimensions.

J. R. Mureika

2007-12-11T23:59:59.000Z

379

The Mixed Phase of Charged AdS Black holes  

E-Print Network [OSTI]

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 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.

Piyabut Burikham; Chatchai Promsiri

2014-08-12T23:59:59.000Z

380

Magnetized Black Hole on Taub-Nut Instanton  

E-Print Network [OSTI]

We present an exact solution to the 5D Einstein-Maxwell-dilaton equations describing a static black hole on Taub-Nut instanton. By construction the solution does not possess a charge, but is magnetized along the compact dimension. As a limit we obtain a new regular solution representing a magnetized Kaluza- Klein monopole. We investigate the relevant physical properties and derive the Smarr-like relations.

Petya G. Nedkova; Stoytcho S. Yazadjiev

2011-12-14T23:59:59.000Z

Note: This page contains sample records for the topic "hydroprobe slim holes" from the National Library of EnergyBeta (NLEBeta).
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381

Bore-hole survey at Camp Century, 1989  

Science Journals Connector (OSTI)

A combination of the directional surveys of the Camp Century borehole from 1966, 1967, 1969 and 1989 has revealed a deformation pattern similar to that measured at Dye-3, South Greenland and Byrd Station, Antarctica showing high deformation rate for Wisconsin ice. Compared to the Dye-3 profile, the deformation shows the same pattern even in details. The surface velocity obtained by integrating the bore hole deformation is in agreement with that obtained from satellite measurements.

N.S Gundestrup; D Dahl-Jensen; B.L Hansen; J Kelty

1993-01-01T23:59:59.000Z

382

Quantum interference in an electron-hole graphene ring system  

SciTech Connect (OSTI)

Quantum interference is observed in a graphene ring system via the Aharonov Bohm effect. As graphene is a gapless semiconductor, this geometry allows to study the unique situation of quantum interference between electrons and holes in addition to the unipolar quantum interference. The period and amplitude of the observed Aharonov-Bohm oscillations are independent of the sign of the applied gate voltage showing the equivalence between unipolar and dipolar interference.

Smirnov, D.; Schmidt, H.; Haug, R. J. [Institut fr Festkrperphysik, Leibniz Universitt Hannover, Appelstr. 2 30167 Hannover (Germany)

2013-12-04T23:59:59.000Z

383

Trapped surfaces in Oppenheimer-Snyder black holes  

E-Print Network [OSTI]

The Oppenheimer-Snyder solution models a homogeneous round dust cloud collapsing to a black hole. Inside its event horizon there is a region through which trapped surfaces pass. We try to determine exactly where the boundary of this region meets the centre of the cloud. We present explicit examples of the relevant trapped (topological) spheres; they extend into the exterior vacuum region, and are carefully matched at the junction between the cloud and the vacuum.

Ingemar Bengtsson; Emma Jakobsson; Jos M. M. Senovilla

2013-06-27T23:59:59.000Z

384

Suspended two-dimensional electron and hole gases  

SciTech Connect (OSTI)

We report on the fabrication of fully suspended two-dimensional electron and hole gases in III-V heterostructures. Low temperature transport measurements verify that the properties of the suspended gases are only slightly degraded with respect to the non-suspended gases. Focused ion beam technology is used to pattern suspended nanostructures with minimum damage from the ion beam, due to the small width of the suspended membrane.

Kazazis, D.; Bourhis, E.; Gierak, J.; Gennser, U. [Laboratoire de Photonique et de Nanostructures, CNRS-LPN, Route de Nozay, 91460 Marcoussis (France); Bourgeois, O. [Institut Nel, CNRS-UJF, BP 166, 38042 Grenoble Cedex 9 (France); Antoni, T. [Laboratoire de Photonique et de Nanostructures, CNRS-LPN, Route de Nozay, 91460 Marcoussis, France and Laboratoire Kastler Brossel, Universit Pierre et Marie Curie, 4 Place Jussieu, 75005 Paris (France)

2013-12-04T23:59:59.000Z

385

A mathematical simulation of horizontal drain-hole performance  

E-Print Network [OSTI]

Science and Technology, Kee-Lung, Taiwan, Republic of China Chairman of Advisory Comnittee: Dr. Ching H. Wu The application of horizontal drain-hole in petroleum industry represents one of the new developments in oil recovery techniques. Many... production condition was simulated. The validity of the computational algorithm employed in the simulator was ascertained using the results obtained from a general purpose black oil simulator, BOSS-AIM. The verification runs were made under a semi...

Cheng, Thomas Ru-Kang

1984-01-01T23:59:59.000Z

386

Particle-hole symmetry broken pseudogap in high temperature superconductors  

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

Particle-hole symmetry broken pseudogap in Particle-hole symmetry broken pseudogap in high temperature superconductors High-temperature (Tc) superconductivity is one of the most important topics in condensed matter physics. Despite extensive studies over more than two decades, the microscopic mechanism of high temperature superconductivity still remains elusive due to many unconventional properties that are not well understood. Among them, the most mysterious behavior of high-Tc superconductor is the nature of so called "pseudogap", which has been a focus of the field for many years. In conventional superconductors, a gap exists in the energy absorption spectrum only below Tc, corresponding to the energy price to pay for breaking a Cooper pair of electrons. In high-Tc cuprate superconductors, an energy gap called the pseudogap exists above Tc but below T*, and is controversially attributed either to pre-formed superconducting pairs or to competing phases. Recently, by carefully studying the "symmetry" of the gap, researchers Makoto Hashimoto and Rui-Hua He, along with their co-workers in Prof. Zhi-Xun Shen's group at Stanford University, have found crucial evidence suggesting that the particle-hole symmetry required by superconductivity is broken in the pseudogap state.

387

Ultrafast Core-Hole Induced Dynamics in Water  

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

Ultrafast Core-Hole Induced Dynamics in Water Print Ultrafast Core-Hole Induced Dynamics in Water Print A thorough understanding of the chemical processes that are initiated when radiation interacts with aqueous systems is essential for many diverse fields, from condensed matter physics to medicine to environmental science. An incoming photon with enough energy to produce a core hole in a water molecule sets off motions that can affect bonding configurations, which in turn affect subsequent chemical-reaction pathways. However, it is a fundamental challenge for the radiation chemistry community to unravel the early time dynamics of electronically excited states in water because their short (femtosecond) time scales are difficult to access directly with pump-probe measurements. Using a combination of isotope substitution experiments and molecular dynamics simulations, researchers from Sweden, Germany, and the U.S. have shown that the ultrafast (0- to 10-fs) dissociation dynamics of liquid water can be successfully probed with x-ray emission spectroscopy.

388

Ultrafast Core-Hole Induced Dynamics in Water  

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

Ultrafast Core-Hole Induced Dynamics in Water Print Ultrafast Core-Hole Induced Dynamics in Water Print A thorough understanding of the chemical processes that are initiated when radiation interacts with aqueous systems is essential for many diverse fields, from condensed matter physics to medicine to environmental science. An incoming photon with enough energy to produce a core hole in a water molecule sets off motions that can affect bonding configurations, which in turn affect subsequent chemical-reaction pathways. However, it is a fundamental challenge for the radiation chemistry community to unravel the early time dynamics of electronically excited states in water because their short (femtosecond) time scales are difficult to access directly with pump-probe measurements. Using a combination of isotope substitution experiments and molecular dynamics simulations, researchers from Sweden, Germany, and the U.S. have shown that the ultrafast (0- to 10-fs) dissociation dynamics of liquid water can be successfully probed with x-ray emission spectroscopy.

389

Ultrafast Core-Hole Induced Dynamics in Water  

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

Ultrafast Core-Hole Induced Dynamics in Water Print Ultrafast Core-Hole Induced Dynamics in Water Print A thorough understanding of the chemical processes that are initiated when radiation interacts with aqueous systems is essential for many diverse fields, from condensed matter physics to medicine to environmental science. An incoming photon with enough energy to produce a core hole in a water molecule sets off motions that can affect bonding configurations, which in turn affect subsequent chemical-reaction pathways. However, it is a fundamental challenge for the radiation chemistry community to unravel the early time dynamics of electronically excited states in water because their short (femtosecond) time scales are difficult to access directly with pump-probe measurements. Using a combination of isotope substitution experiments and molecular dynamics simulations, researchers from Sweden, Germany, and the U.S. have shown that the ultrafast (0- to 10-fs) dissociation dynamics of liquid water can be successfully probed with x-ray emission spectroscopy.

390

Science guide for the Long Valley Caldera deep hole  

SciTech Connect (OSTI)

The Magma Energy Program of the US Department of Energy, Geothermal Technology Division, is planning to begin drilling a deep (6 km) exploration well in Long Valley Caldera, California, in September 1988. The location of the well is in the central part of the caldera, coincident with a large number of shallow (5-7 km) geophysical anomalies identified through many independent investigations. Results from the hole will permit the following: direct investigation of the geophysical anomalies interpreted to be magma; investigation of the patterns and conditions of deep fluid circulation and heat transport below the caldera floor; determination of the amount of collapse and subsequent resurgence of the central portion of Long Valley caldera; and determination of the intrusion history of the central plutonic complex beneath the caldera, and establishment of the relationship of intrusive to eruptive events. The hole will thus provide a stringent test of the hypothesis that magma is still present within the central plutonic complex. If the interpretation of geophysical anomalies is confirmed, the hole will provide the first observations of the environment near a large silicic magma chamber. 80 refs., 7 figs., 2 tabs.

Rundle, J.B.; Eichelberger, J.C. (eds.)

1989-05-01T23:59:59.000Z

391

The Supermassive Black Hole at the Galactic Center  

E-Print Network [OSTI]

The inner few parsecs at the Galactic Center have come under intense scrutiny in recent years, in part due to the exciting broad-band observations of this region, but also because of the growing interest from theorists motivated to study the physics of black hole accretion, magnetized gas dynamics and unusual star formation. The Galactic Center is now known to contain arguably the most compelling supermassive black hole candidate, weighing in at a little over 2.6 million suns. Its interaction with the nearby environment, comprised of clusters of evolved and young stars, a molecular dusty ring, ionized gas streamers, diffuse hot gas, and a hypernova remnant, is providing a wealth of accretion phenomenology and high-energy processes for detailed modeling. In this review, we summarize the latest observational results, and focus on the physical interpretation of the most intriguing object in this region---the compact radio source Sgr A*, thought to be the radiative manifestation of the supermassive black hole.

Fulvio Melia; Heino Falcke

2001-06-08T23:59:59.000Z

392

Backdraft: String Creation in an Old Schwarzschild Black Hole  

E-Print Network [OSTI]

We analyze string production in the background of a Schwarzschild black hole, after developing first quantized methods which capture string-theoretic nonadiabatic effects which can exceed naive extrapolations of effective field theory. Late-time infalling observers are strongly boosted in the near horizon region relative to early observers and formation matter. In the presence of large boosts in flat spacetime, known string and D-brane scattering processes exhibit enhanced string production, even for large impact parameter. This suggests the possibility that the nonadiabatic dynamics required to realize the firewall proposal of AMPS occurs for old black holes, with the late-time observer catalyzing the effect. After setting up this dynamical thought experiment, we focus on a specific case: the production of open strings stretched D-particles, at least one of which falls in late (playing the role of a late time observer). For relatively boosted D-branes, we precisely recover earlier results of Bachas, McAllister and Mitra which we generalize to brane trajectories in the black hole geometry. For two classes of late-time probes, we find a regime of significant non-adiabaticity by horizon crossing, assessing its dependence on the boost in each case. Closed string probes, as well as additional effects in D-brane scattering, may produce other significant non-adiabatic effects depending on the boost, something we leave for further work.

Eva Silverstein

2014-02-21T23:59:59.000Z

393

The Self-Regulated Growth of Supermassive Black Holes  

E-Print Network [OSTI]

We present a series of simulations of the self--regulated growth of supermassive black holes (SMBHs) in galaxies via three different fueling mechanisms: major mergers, minor mergers, and disk instabilities. The SMBHs in all three scenarios follow the same black hole fundamental plane (BHFP) and correlation with bulge binding energy seen in simulations of major mergers, and observed locally. Furthermore, provided that the total gas supply is significantly larger than the mass of the SMBH, its limiting mass is not influenced by the amount of gas available or the efficiency of black hole growth. This supports the assertion that SMBHs accrete until they reach a critical mass at which feedback is sufficient to unbind the gas locally, terminating the inflow and stalling further growth. At the same time, while minor and major mergers follow the same projected correlations (e.g., the $M_{BH}-\\sigma$ and Magorrian relations), SMBHs grown via disk instabilities do not, owing to structural differences between the host bulges. This finding is supported by recent observations of SMBHs in pseudobulges and bulges in barred systems, as compared to those hosted by classical bulges. Taken together, this provides support for the BHFP and binding energy correlations as being more "fundamental" than other proposed correlations in that they reflect the physical mechanism driving the co-evolution of SMBHs and spheroids.

Joshua D. Younger; Philip F. Hopkins; T. J. Cox; Lars Hernquist

2008-04-17T23:59:59.000Z

394

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

SciTech Connect (OSTI)

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

Lemos, Jose P. S.; Zanchin, Vilson T. [Centro Multidisciplinar de Astrofisica - CENTRA, Departamento de Fisica, Instituto Superior Tecnico - IST, Universidade Tecnica de Lisboa - UTL, Avenida Rovisco Pais 1, 1049-001 Lisboa (Portugal); Centro de Ciencias Naturais e Humanas, Universidade Federal do ABC, Rua Santa Adelia, 166, 09210-170, Santo Andre, Sao Paulo (Brazil); Coordenadoria de Astronomia e Astrofisica, Observatorio Nacional-MCT, Rua General Jose Cristino 77, 20921-400 Rio de Janeiro (Brazil)

2011-06-15T23:59:59.000Z

395

Radiation of the Inner Horizon of the Reissner-Nordstrm Black Hole  

E-Print Network [OSTI]

Despite of over thirty years of research of the black hole thermodynamics our understanding of the possible role played by the inner horizons of Reissner-Nordstr\\"om and Kerr-Newman black holes in black hole thermodynamics is still somewhat incomplete: There are derivations which imply that the temperature of the inner horizon is negative and it is not quite clear what this means. Motivated by this problem we perform a detailed analysis of the radiation emitted by the inner horizon of the Reissner-Nordstr\\"om black hole. As a result we find that in a maximally extended Reissner-Nordstr\\"om spacetime virtual particle-antiparticle pairs are created at the inner horizon of the Reissner-Nordstr\\"om black hole such that real particles with positive energy and temperature are emitted towards the singularity from the inner horizon and, as a consequence, antiparticles with negative energy are radiated away from the singularity through the inner horizon. We show that these antiparticles will come out from the white hole horizon in the maximally extended Reissner-Nordstr\\"om spacetime, at least when the hole is near extremality. The energy spectrum of the antiparticles leads to a positive temperature for the white hole horizon. In other words, our analysis predicts that in addition to the radiation effects of black hole horizons, also the white hole horizon radiates. The black hole radiation is caused by the quantum effects at the outer horizon, whereas the white hole radiation is caused by the quantum effects at the inner horizon of the Reissner-Nordstr\\"om black hole.

A. Peltola; J. Makela

2005-08-23T23:59:59.000Z

396

Rock Sampling At Seven Mile Hole Area (Larson, Et Al., 2009) | Open Energy  

Open Energy Info (EERE)

Seven Mile Hole Area (Larson, Et Al., 2009) Seven Mile Hole Area (Larson, Et Al., 2009) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Rock Sampling At Seven Mile Hole Area (Larson, Et Al., 2009) Exploration Activity Details Location Seven Mile Hole Area Exploration Technique Rock Sampling Activity Date Usefulness not indicated DOE-funding Unknown Notes The distribution of hydrothermally altered rocks was mapped over about 1 km2 in the Sevenmile Hole area. Two to four kilogram hand samples located by a handheld GPS were collected from many outcrops for laboratory analyses References Peter B. Larson, Allison Phillips, David John, Michael Cosca, Chad Pritchard, Allen Andersen, Jennifer Manion (2009) A Preliminary Study Of Older Hot Spring Alteration In Sevenmile Hole, Grand Canyon Of The

397

Space X-ray Solves Mysteries of Black Holes | Department of Energy  

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

Space X-ray Solves Mysteries of Black Holes Space X-ray Solves Mysteries of Black Holes Space X-ray Solves Mysteries of Black Holes March 13, 2013 - 3:57pm Addthis Space X-ray Solves Mysteries of Black Holes Anne M. Stark Senior Public Information Officer, Lawrence Livermore National Laboratory "We know that black holes have a strong link to their host galaxy." Astrophysicist Bill Craig, a member of the LLNL team An international team including Lawrence Livermore National Laboratory scientists has definitively measured the spin rate of a supermassive black hole for the first time. The findings, made by the two X-ray space observatories, NASA's Nuclear Spectroscopic Telescope Array (NuSTAR) and the European Space Agency's XMM-Newton, solve a long-standing debate about similar measurements in

398

Thermal Gradient Holes At Kilauea Summit Area (Keller, Et Al., 1979) | Open  

Open Energy Info (EERE)

Thermal Gradient Holes At Kilauea Summit Area (Keller, Et Al., 1979) Thermal Gradient Holes At Kilauea Summit Area (Keller, Et Al., 1979) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Thermal Gradient Holes At Kilauea Summit Area (Keller, Et Al., 1979) Exploration Activity Details Location Kilauea Summit Area Exploration Technique Thermal Gradient Holes Activity Date Usefulness useful DOE-funding Unknown Notes A deep borehole was drilled at the summit of Kilauea volcano, Hawaii, between April 6 and July 9, 1973. The hole is located approximately 1 km south of the edge of Halemaumau crater (Figs. 1 and 2), a crater within the summit caldera of the volcano. The total depth of the hole is 1262 m (4141 ft) measured from the derrick floor at an altitude of 1102 m (3616 ft). A description of the drilling program and some of the results obtained have

399

Suppression of star formation in early-type galaxies by feedback from supermassive black holes  

E-Print Network [OSTI]

Detailed high-resolution observations of the innermost regions of nearby galaxies have revealed the presence of supermassive black holes1. These black holes may interact with their host galaxies by means of 'feedback' in the form of energy and material jets; this feedback affects the evolution of the host and gives rise to observed relations between the black hole and the host. Here we report observations of the ultraviolet emissions of massive early-type galaxies. We derive an empirical relation for a critical black-hole mass (as a function of velocity dispersion) above which the outflows from these black holes suppress star formation in their hosts by heating and expelling all available cold gas. Supermassive black holes are negligible in mass compared to their hosts but nevertheless seem to play a critical role in the star formation history of galaxies.

Kevin Schawinski; Sadegh Khochfar; Sugata Kaviraj; Sukyoung K. Yi; Alessandro Boselli; Tom Barlow; Tim Conrow; Karl Forster; Peter G. Friedman; D. Chris Martin; Patrick Morrissey; Susan Neff; David Schiminovich; Mark Seibert; Todd Small; Ted K. Wyder; Luciana Bianchi; Jose Donas; Tim Heckman; Young-Wook Lee; Barry Madore; Bruno Milliard; R. Michael Rich; Alex Szalay

2006-08-24T23:59:59.000Z

400

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

ScienceCinema (OSTI)

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

None

2011-10-06T23:59:59.000Z

Note: This page contains sample records for the topic "hydroprobe slim holes" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

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

ScienceCinema (OSTI)

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

None

2011-10-06T23:59:59.000Z

402

Corrected form of the first law of thermodynamics for regular black holes  

E-Print Network [OSTI]

We show by explicit computations that there is a superficial inconsistency between the conventional first law of black hole thermodynamics and Bekenstein-Hawking area law for three types of regular black holes. The corrected form of the first law for these regular black holes is given. The derivation relies on the general structure of the energy-momentum tensor of the matter fields. When the black hole mass parameter $M$ is included in the energy-momentum tensor, the conventional form of the first law should be modified with an extra factor. In this case, the black hole mass $M$ can no longer be considered as the internal energy of the regular black holes.

Meng-Sen Ma; Ren Zhao

2014-11-04T23:59:59.000Z

403

Corrected form of the first law of thermodynamics for regular black holes  

E-Print Network [OSTI]

We show by explicit computations that there is a superficial inconsistency between the conventional first law of black hole thermodynamics and Bekenstein-Hawking area law for three types of regular black holes. The corrected form of the first law for these regular black holes is given. The derivation relies on the general structure of the energy-momentum tensor of the matter fields. When the black hole mass parameter $M$ is included in the energy-momentum tensor, the conventional form of the first law should be modified with an extra factor. In this case, the black hole mass $M$ can no longer be considered as the internal energy of the regular black holes.

Ma, Meng-Sen

2014-01-01T23:59:59.000Z

404

Double Core-Hole Production in N{sub 2}: Beating the Auger Clock  

SciTech Connect (OSTI)

We investigate the creation of double K-shell holes in N{sub 2} molecules via sequential absorption of two photons on a time scale shorter than the core-hole lifetime by using intense x-ray pulses from the Linac Coherent Light Source free electron laser. The production and decay of these states is characterized by photoelectron spectroscopy and Auger electron spectroscopy. In molecules, two types of double core holes are expected, the first with two core holes on the same N atom, and the second with one core hole on each N atom. We report the first direct observations of the former type of core hole in a molecule, in good agreement with theory, and provide an experimental upper bound for the relative contribution of the latter type.

Fang, L.; Berrah, N. [Physics Department, Western Michigan University, Kalamazoo, Michigan 49008 (United States); Hoener, M. [Physics Department, Western Michigan University, Kalamazoo, Michigan 49008 (United States); Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Gessner, O.; Kornilov, O. [Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Tarantelli, F. [Dipartimento di Chimica, Universitadi Perugia, and ISTM-CNR, 06123 Perugia (Italy); Pratt, S. T.; Kanter, E. P. [Argonne National Laboratory, Argonne, Illinois 60439 (United States); Buth, C. [PULSE Institute for Ultrafast Energy Science, SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Department of Physics, Louisiana State University, Baton Rouge, Louisiana 70803 (United States); Guehr, M.; Bucksbaum, P. H.; Cryan, J.; Glownia, M. [PULSE Institute for Ultrafast Energy Science, SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Bostedt, C.; Bozek, J. D.; Coffee, R. [Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Chen, M. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Kukk, E. [Department of Physics and Astronomy, University of Turku 20014 Turku (Finland); Leone, S. R. [Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Departments of Chemistry and Physics, University of California Berkeley, California 94710 (United States)

2010-08-20T23:59:59.000Z

405

Double core hole production in N{sub 2} : beating the auger clock.  

SciTech Connect (OSTI)

We investigate the creation of double K-shell holes in N{sub 2} molecules via sequential absorption of two photons on a time scale shorter than the core-hole lifetime by using intense x-ray pulses from the Linac Coherent Light Source free electron laser. The production and decay of these states is characterized by photoelectron spectroscopy and Auger electron spectroscopy. In molecules, two types of double core holes are expected, the first with two core holes on the same N atom, and the second with one core hole on each N atom. We report the first direct observations of the former type of core hole in a molecule, in good agreement with theory, and provide an experimental upper bound for the relative contribution of the latter type.

Fang, L.; Hoener, M.; Gessner, O.; Tarantelli, F.; Pratt, S. T.; Kornilov, O.; Buth, C.; Guhr, M.; Kanter, E. P.; Bostedt, C.; Bozek, J. D.; Bucksbaum, P. H.; Chen, M.; Coffee, R.; Cryan, J.; Glownia, J. M.; Kukk, E.; Leone, S. R.; Berrah, N. (Chemical Sciences and Engineering Division); ( XSD); (Western Michigan Univ.); (LBNL); (Univ. di Perugia); (Louisiana State Univ.); (SLAC National Accelerator Lab.); (LLNL); (Univ. of Turku); (Univ. of California at Berkeley)

2010-01-01T23:59:59.000Z

406

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

ScienceCinema (OSTI)

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

None

2011-10-06T23:59:59.000Z

407

Field Mapping At Seven Mile Hole Area (Larson, Et Al., 2009) | Open Energy  

Open Energy Info (EERE)

Seven Mile Hole Area (Larson, Et Al., 2009) Seven Mile Hole Area (Larson, Et Al., 2009) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Field Mapping At Seven Mile Hole Area (Larson, Et Al., 2009) Exploration Activity Details Location Seven Mile Hole Area Exploration Technique Field Mapping Activity Date Usefulness not indicated DOE-funding Unknown Notes The distribution of hydrothermally altered rocks was mapped over about 1 km2 in the Sevenmile Hole area. Two to four kilogram hand samples located by a handheld GPS were collected from many outcrops K735for laboratory analyses References Peter B. Larson, Allison Phillips, David John, Michael Cosca, Chad Pritchard, Allen Andersen, Jennifer Manion (2009) A Preliminary Study Of Older Hot Spring Alteration In Sevenmile Hole, Grand Canyon Of The

408

Thermal Gradient Holes At Upper Hot Creek Ranch Area (Benoit & Blackwell,  

Open Energy Info (EERE)

Hot Creek Ranch Area (Benoit & Blackwell, Hot Creek Ranch Area (Benoit & Blackwell, 2006) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Thermal Gradient Holes At Upper Hot Creek Ranch Area (Benoit & Blackwell, 2006) Exploration Activity Details Location Upper Hot Creek Ranch Area Exploration Technique Thermal Gradient Holes Activity Date Usefulness not useful DOE-funding Unknown Notes Ten temperature gradient holes up to 500' deep were initially planned but higher than anticipated drilling and permitting costs within a fixed budget reduced the number of holes to five. Four of the five holes drilled to depths of 300 to 400' encountered temperatures close to the expected regional thermal background conditions. These four holes failed to find any evidence of a large thermal anomaly surrounding the UHCR hot springs. The

409

Black holes and Boyle's law -- the thermodynamics of the cosmological constant  

E-Print Network [OSTI]

When the cosmological constant, $\\Lambda$, is interpreted as a thermodynamic variable in the study of black hole thermodynamics a very rich structure emerges. It is natural to interpret $\\Lambda$ as a pressure and define the thermodynamically conjugate variable to be the thermodynamic volume of the black hole (which need not bear any relation to the geometric volume). Recent progress in this new direction for black hole thermodynamics is reviewed.

Dolan, Brian P

2014-01-01T23:59:59.000Z

410

Thermodynamic Geometry of Reissener-Nordstrm-de Sitter black hole and its extremal case  

E-Print Network [OSTI]

We study the thermodynamics and the different thermodynamic geometric methods of Reissener-Nordstr\\"{o}m-de Sitter black hole and its extremal case, which is similar to the de Sitter black hole coupled to a scalar field, rather called an MTZ black hole. While studying the thermodynamics of the systems, we could find some abnormalities. In both cases, the thermodynamic geometric methods could give the correct explanation for the all abnormal thermodynamic behaviors in the system.

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

2014-04-27T23:59:59.000Z

411

Analytic treatment of the black-hole bomb The Ruppin Academic Center, Emeq Hefer 40250, Israel and The Hadassah Institute, Jerusalem 91010, Israel  

E-Print Network [OSTI]

, the mass term effectively works as a mirror, reflecting the scattered wave back towards the black hole Schwarzschild black hole. If a Schwarzschild black hole is perturbed, then the perturba- tion will oscillate surrounds the black hole by a reflecting mirror, the wave will bounce back and forth between the black hole

Hod, Oded

412

A Statistical Analysis Of Bottom-Hole Temperature Data In The...  

Open Energy Info (EERE)

Considerable differences in the spread of bottom-hole temperature values from petroleum exploration well logs plotted as a function of depth are observed over a region of...

413

E-Print Network 3.0 - astrophysical black holes Sample Search...  

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

PDF DIR ASTROPHYSICS Summary: dwarfs, neutron stars, black holes - supernovae - gamma-ray bursts stellar evolution versus galaxy... TALK DIR PDF DIR MASTER ASTROPHYSICS ...

414

Core Holes At Kilauea East Rift Geothermal Area (Bargar, Et Al...  

Open Energy Info (EERE)

Activity Details Location Kilauea East Rift Geothermal Area Exploration Technique Core Holes Activity Date 1989 - 1991 Usefulness useful DOE-funding Unknown Exploration...

415

Unified First Law and Thermodynamics of Dynamical Black Hole in n-dimensional Vaidya Spacetime  

E-Print Network [OSTI]

As a simple but important example of dynamical black hole, we analysis the dynamical black hole in $n$-dimensional Vaidya spacetime in detail. We investigated the thermodynamics of field equation in $n$-dimensional Vaidya spacetime. The unified first law was derived in terms of the methods proposed by Sean A Hayward. The first law of dynamical black hole was obtained by projecting the unified first law along the trapping horizon. At last, the second law of dynamical black hole is also discussed.

Ji-Rong Ren; Ran Li

2007-05-30T23:59:59.000Z

416

Gedanken experiments on nearly extremal black holes and the third law  

SciTech Connect (OSTI)

A gedanken experiment in which a black hole is pushed to spin at its maximal rate by tossing into it a test body is considered. After demonstrating that this is kinematically possible for a test body made of reasonable matter, we focus on its implications for black hole thermodynamics and the apparent violation of the third law (unattainability of the extremal black hole). We argue that this is not an actual violation, due to subtleties in the absorption process of the test body by the black hole, which are not captured by the purely kinematic considerations.

Chirco, Goffredo; Liberati, Stefano [SISSA-International School for Advanced Studies, Via Bonomea 265, 34136 Trieste (Italy) and INFN sezione di Trieste (Italy); Sotiriou, Thomas P. [Department of Applied Mathematics and Theoretical Physics, Center for Mathematical Sciences, University of Cambridge, Wilberforce Road, Cambridge, CB3 0WA (United Kingdom)

2010-11-15T23:59:59.000Z

417

E-Print Network 3.0 - agn black hole Sample Search Results  

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

with the Iron Line Summary: a Schwarzschild black hole. The beaming is a function of inclination, meaning that blue- shifting will increase... that the iron line profile...

418

Thermal Gradient Holes At Fort Bliss Area (DOE GTP) | Open Energy...  

Open Energy Info (EERE)

Fort Bliss Area (DOE GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Thermal Gradient Holes At Fort Bliss Area (DOE GTP) Exploration...

419

Slimhole Drilling, Logging, and Completion Technology - An Update  

SciTech Connect (OSTI)

Using slim holes (diameter < 15 cm) for geothermal exploration and small-scale power production can produce significant cost savings compared to conventional rotary-drilling methods. In addition, data obtained from slim holes can be used to lower the risks and costs associated with the drilling and completion of large-diameter geothermal wells. As a prime contractor to the U.S. Department of Energy (DOE), Sandia National Laboratories has worked with industry since 1992 to develop and promote drilling, testing, and logging technology for slim holes. This paper describes the current status of work done both in-house and contracted to industry. It focuses on drilling technology, case histories of slimhole drilling projects, data collection and rig instrumentation, and high-temperature logging tools.

FINGER,JOHN T.; JACOBSON,RONALD D.

1999-10-07T23:59:59.000Z

420

The black hole challenge in Randall-Sundrum II model  

E-Print Network [OSTI]

Models postulating the existence of additional spacelike dimensions of macroscopic or even infinite size, while viewing our observable universe as merely a 3-brane living in a higher-dimensional bulk were a major breakthrough when proposed some 15 years ago. The most interesting among them both in terms of elegance of the setup and of the richness of the emerging phenomenology is the Randall-Sundrum II model where one infinite extra spacelike dimension is considered with an AdS topology, characterized by the warping effect caused by the presence of a negative cosmological constant in the bulk. A major drawback of this model is that despite numerous efforts no line element has ever been found that could describe a stable, regular, realistic black hole. Finding a smoothly behaved such solution supported by the presence of some more or less conventional fields either in the bulk and/or on the brane is the core of the black hole challenge. After a comprehensive presentation of the details of the model and the analysis of the significance and the utility of getting a specific analytic black hole solution, several (unsuccessful) analytic and numerical approaches to the problem developed over the years are presented with some discussion about their results. The chapter closes with the latest numerical results that actually consists a major advancement in the effort to address the challenge, the presentation of the most recent analytic work trying (and unfortunately failing) to build a solution assuming the existence of unconventional scalar fields and some ideas about the routes the forthcoming analytic approaches should explore.

Nikolaos D. Pappas

2014-09-02T23:59:59.000Z

Note: This page contains sample records for the topic "hydroprobe slim holes" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Investigating Binary Black Hole Mergers with Principal Component Analysis  

E-Print Network [OSTI]

Despite recent progress in numerical simulations of the coalescence of binary black hole systems, highly asymmetric spinning systems and the construction of accurate physical templates remain challenging and computationally expensive. We explore the feasibility of a prompt and robust test of whether the signals exhibit evidence for generic features that can educate new simulations. We form catalogs of numerical relativity waveforms with distinct physical effects and compute the relative probability that a gravitational wave signal belongs to each catalog. We introduce an algorithm designed to perform this task for coalescence signals using principal component analysis of waveform catalogs and Bayesian model selection and demonstrate its effectiveness.

James Clark; Laura Cadonati; James Healy; Ik Siong Heng; Josh Logue; Nicholas Mangini; Lionel London; Larne Pekowsky; Deirdre Shoemaker

2014-06-20T23:59:59.000Z

422

Geodesic Structure of the Schwarzschild Black Hole in Rainbow Gravity  

E-Print Network [OSTI]

In this paper we study the geodesic structure of the Schwarzschild black hole in rainbow gravity analyzing the behavior of null and time-like geodesic. We find that the structure of the geodesics essentially does not change when the semi-classical effects are included. However, we can distinguish different scenarios if we take into account the effects of rainbow gravity. Depending on the type of rainbow functions under consideration, inertial and external observers see very different situations in radial and non radial motion of a test particles.

Carlos Leiva; Joel Saavedra; Jose Villanueva

2008-12-09T23:59:59.000Z

423

Interacting spins and holes in zigzag edge nanographene  

SciTech Connect (OSTI)

We have investigated charge and spin gap properties of zigzag edge graphene nanoribbons (ZGNRs) modeled within Hubbard Hamiltonian with onsite electron-electron interaction using semi-empirical many-body configuration interaction (CI) method. The charge gap behavior resembles the mean-field results, showing minima near Dirac point. We have observed unprecedented gap-less spin excitations over the flat band region. Moreover, doping the ZGNRs with holes reduces both the charge and spin gaps, inducing metallic and magnetic behavior, which can be exploited to fabricate spintronic devices.

Dutta, Sudipta; Wakabayashi, Katsunori [International Center for Materials Nanoarchitechtonics (WPI-MANA) National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki - 305-0044 (Japan)

2013-12-04T23:59:59.000Z

424

Solar System tests of Ho?ava-Lifshitz black holes  

E-Print Network [OSTI]

In the present paper we consider the possibility of observationally testing Horava gravity at the scale of the Solar System, by considering the classical tests of general relativity (perihelion precession of the planet Mercury, deflection of light by the Sun and the radar echo delay) for the Kehagias-Sfetsos asymptotically flat black hole solution of Horava-Lifshitz gravity. All these gravitational effects can be fully explained in the framework of the vacuum solution of Horava gravity, and it is shown that the analysis of the classical general relativistic tests severely constrain the free parameter of the solution.

Francisco S. N. Lobo; Tiberiu Harko; Zoltn Kovcs

2010-01-20T23:59:59.000Z

425

Kappa - Poincare dispersion relations and the black hole radiation  

E-Print Network [OSTI]

Following the methods developed by Corley and Jacobson, we consider qualitatively the issue of Hawking radiation in the case when the dispersion relation is dictated by quantum kappa-Poincare algebra. This relation corresponds to field equations that are non-local in time, and, depending on the sign of the parameter kappa, to sub- or superluminal signal propagation. We also derive the conserved inner product, that can be used to count modes, and therefore to obtain the spectrum of black hole radiation in this case.

A. Blaut; J. Kowalski-Glikman; D. Nowak-Szczepaniak

2001-08-28T23:59:59.000Z

426

Role of dipole charges in black hole thermodynamics  

SciTech Connect (OSTI)

Modern derivations of the first law of black holes appear to show that the only charges that arise are monopole charges that can be obtained by surface integrals at infinity. However, the recently discovered five dimensional black ring solutions empirically satisfy a first law in which dipole charges appear. We resolve this contradiction and derive a general form of the first law for black rings. Dipole charges do appear together with a corresponding potential. We also include theories with Chern-Simons terms and generalize the first law to other horizon topologies and more generic local charges.

Copsey, Keith; Horowitz, Gary T. [Department of Physics, UCSB, Santa Barbara, California 93106 (United States)

2006-01-15T23:59:59.000Z

427

Microscopic quantum structure of black hole and vacuum versus quantum statistical origin of gravity  

E-Print Network [OSTI]

The Planckon densely piled model of vacuum is proposed. Based on this model, the microscopic quantum structure of Schwarzschild black hole and quantum statistical origin of its gravity are studied. The cutoff of black hole horizon leads to Casimir effect inside the horizon. This effect makes the inside vacuum has less zero quantum fluctuation energy than that of outside vacuum and the spin 1/2 radiation hole excitations are resulted inside the horizon. The mean energy of the radiation hole excitations is related to the temperature decrease of the Hawking-Unruh type by the period law of the Fermion temperature greens function and a temperature difference as well as gravity are created on the horizon. A dual relation of the gravity potentials between inside and outside regions of the black hole is found. An attractor behaviour of the horizon surface is unveiled. The gravity potential inside the black hole is linear in radial coordinate and no singularity exists at the origin of the black hole, in contrast to the conventional conjecture. All the particles absorbed by the black hole have fallen down to the horizon and converted into spin 1/2 radiation quanta with the mean energy related to the Hawking-Unruh temperature, the thermodynamic equilibrium and the mechanical balance make the radiation quanta be tightly bound in the horizon. The gravitation mass $2M$ and physical mass $M$ of the black hole are calculated. The calculated entropy of the black hole is well consistent with Hawking. Outside the horizon, there exist thermodynamic non-equilibrium and mechanical non-balance which lead to an outward centrifugal energy flow and an inward gravitation energy flow. The lost vacuum energy in the negative gravitation potential region has been removed to the black hole surface to form a spherical Planckon shell with the thickness of Planckon diameter so that energy conservation is guaranteed.

Shun-Jin Wang

2014-10-28T23:59:59.000Z

428

Spray atomization characteristics of a GDI injector equipped with a group-hole nozzle  

Science Journals Connector (OSTI)

Abstract The main purpose of this paper is to analyze the spray characteristics of a group-hole nozzle in terms of spray behavior and atomization process in comparison to the characteristics of a single-hole nozzle as reference. Spray visualization and PDPA (phase Doppler particle analyzer) experiments were performed using a GDI adjustable injector, which can adopt a different type of nozzle at free spray conditions. By analyzing the spray development behavior and distribution of droplet velocity and diameter based on a time series, and comparing these results with that of a single-hole nozzle, the effects of the group-hole nozzle on the spray characteristics in a GDI injection were elucidated. Experimental results showed that the development processes of spray behavior from a group-hole nozzle were similar to that of the single-hole nozzle. Both the sprays had similar spray tip penetration and dispersion at the same stages of development. However, owing to the constant spray momentum from a spray interaction, the spray behavior from the group-hole nozzle seemed to be more stable than that of the single-hole nozzle. In terms of the averaged droplet size, the group-hole nozzle held an advantage over the single-hole nozzle in decreasing Sauter mean diameter (SMD) by approximately 2?m. In addition, in comparison to the spatial distribution of droplet diameter and velocity between them, it can be confirmed that the group-hole nozzle has strong effects on reduction in diameter as well as rapid dispersion of droplet due to active air entrainment. These atomization characteristics are considered as an important advantages for improving mixture formation in GDI engine.

Sanghoon Lee; Sungwook Park

2014-01-01T23:59:59.000Z

429

Kinematics of geodesic flows in stringy black hole backgrounds  

E-Print Network [OSTI]

We study the kinematics of timelike geodesic congruences in two and four dimensions in spacetime geometries representing stringy black holes. The Raychaudhuri equations for the kinematical quantities (namely, expansion, shear and rotation) characterising such geodesic flows are written down and subsequently solved analytically (in two dimensions) and numerically (in four dimensions) for specific geodesics flows. We compare between geodesic flows in dual (electric and magnetic) stringy black hole backgrounds in four dimensions, by showing the differences that arise in the corresponding evolutions of the kinematic variables. The crucial role of initial conditions and the spacetime curvature on the evolution of the kinematical variables is illustrated. Some novel general conclusions on geodesic focusing are obtained from the analytical and numerical findings. We also propose new quantifiers in terms of (a) the time (affine parameter) of approach to a singularity and (b) the location of extrema in the functional evolution of the kinematic variables, which may be used to distinguish between flows in different geometries. In summary, our quantitative findings bring out hitherto unknown features of the kinematics of geodesic flows, which, otherwise, would have remained overlooked, if we confined ourselves to only a qualitative analysis.

Anirvan Dasgupta; Hemwati Nandan; Sayan Kar

2009-06-12T23:59:59.000Z

430

Tidal Capture of Stars by Intermediate-Mass Black Holes  

E-Print Network [OSTI]

Recent X-ray observations and theoretical modelling have made it plausible that some ultraluminous X-ray sources (ULX) are powered by intermediate-mass black holes (IMBHs). N-body simulations have also shown that runaway merging of stars in dense star clusters is a way to form IMBHs. In the present paper we have performed N-body simulations of young clusters such as MGG-11 of M82 in which IMBHs form through runaway merging. We took into account the effect of tidal heating of stars by the IMBH to study the tidal capture and disruption of stars by IMBHs. Our results show that the IMBHs have a high chance of capturing stars through tidal heating within a few core relaxation times and we find that 1/3 of all runs contain a ULX within the age limits of MGG-11, a result consistent with the fact that a ULX is found in this galaxy. Our results strengthen the case for some ULX being powered by intermediate-mass black holes.

H. Baumgardt; C. Hopman; S. Portegies Zwart; J. Makino

2005-11-27T23:59:59.000Z

431

CALIBRATING C-IV-BASED BLACK HOLE MASS ESTIMATORS  

SciTech Connect (OSTI)

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

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

2013-06-20T23:59:59.000Z

432

Initial data for perturbed Kerr black holes on hyperboloidal slices  

E-Print Network [OSTI]

We construct initial data corresponding to a single perturbed Kerr black hole in vacuum. These data are defined on specific hyperboloidal ("ACMC-") slices on which the mean extrinsic curvature K asymptotically approaches a constant at future null infinity scri+. More precisely, we require that K obeys the Taylor expansion K=K0 + s^4 where K0 is a constant and s describes a compactified spatial coordinate such that scri+ is represented by s=0. We excise the singular interior of the black hole and assume a marginally outer trapped surface as inner boundary of the computational domain. The momentum and Hamiltonian constraints are solved by means of pseudo-spectral methods and we find exponential rates of convergence of our numerical solutions. Some physical properties of the initial data are studied with the calculation of the Bondi Mass, together with a multipole decomposition of the horizon. We probe the standard picture of gravitational collapse by assessing a family of Penrose-like inequalities and discuss in particular their rigidity aspects. Dynamical evolutions are planned in a future project.

David Schinkel; Marcus Ansorg; Rodrigo Panosso Macedo

2014-08-26T23:59:59.000Z

433

Quasilinear Carbon Transport In An Impurity Hole Plasma In LHD  

SciTech Connect (OSTI)

Comprehensive electrostatic gyrokinetic linear stability calculations for ion-scale microinstabilities in an LHD plasma with an ion-ITB and carbon "impurity hole" are used to make quasilinear estimates of particle flux to explore whether microturbulence can explain the observed outward carbon fluxes that flow "up" the impurity density gradient. The ion temperature is not stationary in the ion-ITB phase of the simulated discharge, during which the core carbon density decreases continuously. To fully sample these varying conditions the calculations are carried out at three radial locations and four times. The plasma parameter inputs are based on experimentally measured profiles of electron and ion temperature, as well as electron and carbon density. The spectroscopic line-average ratio of hydrogen and helium densities is used to set the density of these species. Three ion species (H,He,C) and the electrons are treated kinetically, including collisions. Electron instability drive does enhance the growth rate significantly, but the most unstable modes have characteristics of ion temperature gradient (ITG) modes in all cases. As the carbon density gradient is scanned between the measured value and zero, the quasilinear carbon flux is invariably inward when the carbon density profile is hollow, so turbulent transport due to the instabilities considered here does not explain the observed outward flux of impurities in impurity hole plasmas. The stiffness of the quasilinear ion heat flux is found to be 1.7-2.3, which is lower than several estimates in tokamaks.

Mikkelsen, David R. [PPPL; Tanaka, K. [NIFS; Nunami, M. [NIFS; Watanabe, T-H. [Nagoya University; Sugama, H. [NIFS; Yoshinuma, M. [NIFS; Suzuki, Y. [NIFS; Goto, M. [NIFS; Morita, S. [NIFS; Wieland, B. [NIFS; Yamada, I. [NIFS; Yashura, R. [NIFS; Akiyama, T. [NIFS; Pablant, Novimir A. [PPPL

2014-04-01T23:59:59.000Z

434

Fermion absorption cross section of a Schwarzschild black hole  

E-Print Network [OSTI]

We study the absorption of massive spin-half particles by a small Schwarzschild black hole by numerically solving the single-particle Dirac equation in Painleve-Gullstrand coordinates. We calculate the absorption cross section for a range of gravitational couplings Mm/m_P^2 and incident particle energies E. At high couplings, where the Schwarzschild radius R_S is much greater than the wavelength lambda, we find that the cross section approaches the classical result for a point particle. At intermediate couplings we find oscillations around the classical limit whose precise form depends on the particle mass. These oscillations give quantum violations of the equivalence principle. At high energies the cross section converges on the geometric-optics value of 27 \\pi R_S^2/4, and at low energies we find agreement with an approximation derived by Unruh. When the hole is much smaller than the particle wavelength we confirm that the minimum possible cross section approaches \\pi R_S^2/2.

Chris Doran; Anthony Lasenby; Sam Dolan; Ian Hinder

2005-03-04T23:59:59.000Z

435

Feedback-regulated Super Massive Black Hole Seed Formation  

E-Print Network [OSTI]

The nature of the seeds of high-redshift supermassive black holes (SMBHs) is a key question in cosmology. Direct collapse black holes (DCBH) that form in pristine, atomic-line cooling halos, illuminated by a Lyman-Werner (LW) UV flux exceeding a critical threshold J_crit, represent an attractive possibility. We investigate when and where these conditions are met during cosmic evolution. For the LW intensity, J_LW, we account for departures from the background value in close proximity to star forming galaxies. For the pristine halo fraction, we account for both (i) supernova driven outflows, and (ii) the inherent pollution from progenitor halos. We estimate the abundance of DCBH formation sites, n_DCBH(z), and find that it increases with cosmic time from n_DCBH(z=20) ~ 1e-12 -1e-7 cMpc^-3 to n_DCBH(z=10) ~ 1e-10 - 1e-5 cMpc^-3. Our analysis shows the possible importance of galactic winds, which can suppress the predicted n_DCBH by several orders of magnitude, and cause DCBH formation to preferentially occur ar...

Dijkstra, Mark; Mesinger, Andrei

2014-01-01T23:59:59.000Z

436

Observing another universe through ringholes and Klein-bottle holes  

Science Journals Connector (OSTI)

It is argued that whereas the Shatskiy single rings produced by the gravitational inner field of a spherically symmetric wormhole and the concentric double Einstein rings generated by a toroidal ringhole could not be used without some uncertainty to identify the presence of such tunnelings in the universe or the existence of a parallel universe, the image which the inner gravitational field of a nonorientable Klein-bottle hole tunneling would leave by lensing a single luminous source is that of a truncated double spiral, which is a signature that cannot be attributed to any other single or composite astronomical object in whichever universe it may be placed. In this report we argue some more reasons to predict that such a signature would imply the discovery of one such nonorientable tunneling in our or other universe. After all, a nonorientable Klein-bottle hole is also a perfectly valid solution to the Einstein equations, and the stuff which would make it feasible is becoming more and more familiar in cosmology.

Pedro F. Gonzlez-Daz and Ana Alonso-Serrano

2011-07-20T23:59:59.000Z

437

A Slowly Rotating Black Hole in Horava-Lifshitz Gravity and a 3+1 Dimensional Topological Black Hole: Motion of Particles and BSW Mechanism  

E-Print Network [OSTI]

The motion of a neutral particle in the vicinity of a slowly rotating black hole in the Horava-Lifshitz theory of gravity and 3+1 dimensional topological Lifshitz black hole is investigated. Geodesics for radial motion of the particles are also plotted. Some different cases of the orbital motion of the particle are discussed where maximum and minimum values of the effective potential are calculated. Further the Ba\\~{n}ados, Silk and West (BSW) mechanism is studied for these black holes. It is shown that the centre-of-mass energy (CME) of two colliding uncharged particles at the horizon of these black holes remains finite. Thus the BSW effect cannot be seen in these cases.

Hussain, Ibrar; Majeed, Bushra

2014-01-01T23:59:59.000Z

438

Electron-hole excitations and optical spectra from first principles Michael Rohlfing  

E-Print Network [OSTI]

Electron-hole excitations and optical spectra from first principles Michael Rohlfing Institut fu April 2000 We present a recently developed approach to calculate electron-hole excitations of the electronic system by the corresponding one- and two-particle Green's function. The method combines three

Wu, Zhigang

439

Stress-energy tensor of a radiating sphere inclosing black hole  

E-Print Network [OSTI]

We consider a uniformly luminous radiating sphere and a static black hole located in the center of that sphere. We give analytic formulas for radiation stress-energy tensor components in such a configuration, for the observer located at an arbitrary distance from the static black hole horizon.

Wielgus, Maciek

2015-01-01T23:59:59.000Z

440

Enhanced Hole Transport in Short-Channel Strained-SiGe p-MOSFETs  

E-Print Network [OSTI]

Hole mobility and velocity are extracted from scaled strained-Si[subscript 0.4]5Ge[subscript 0.55]channel p-MOSFETs on insulator. Devices have been fabricated with sub-100-nm gate lengths, demonstrating hole mobility and ...

Gomez, Leonardo

Note: This page contains sample records for the topic "hydroprobe slim holes" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

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

SciTech Connect (OSTI)

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

Craig, Bill

2013-09-10T23:59:59.000Z

442

Physics 290H and Astronomy 250 The Formation and Evolution of Massive Black Holes  

E-Print Network [OSTI]

provide a useful introduction to the literature. The speci#12;c topics for each week, and the associated readings, will be given on the website. 1. Books Black Holes, White Dwarfs & Neutron Stars, S. L. Shapiro, 2003, Bristol Coevolution of Black Holes and Galaxies, ed. L. C. Ho (Cambridge); available online

Wurtele, Jonathan

443

Super-Eddington Mechanical Power of an Accreting Black Hole in M83  

Science Journals Connector (OSTI)

...of plausible shock velocities (fig. S6). We conclude...LEdd (from the BH mass constraints). We...mp is the proton mass and {mu} the mean atomic weight...years. The expansion velocity vs = dR/dt = (3...A. , Black hole winds . Mon. Not. R...accreting stellar mass black holes as ultraluminous...

R. Soria; K. S. Long; W. P. Blair; L. Godfrey; K. D. Kuntz; E. Lenc; C. Stockdale; P. F. Winkler

2014-03-21T23:59:59.000Z

444

Dynamics of photogenerated holes in surface modified ?-Fe2O3 photoanodes for solar water splitting  

Science Journals Connector (OSTI)

...photogenerated holes in surface modified {alpha}-Fe2O3 photoanodes for solar water splitting 10...primarily to enhanced electron depletion in the Fe2O3 for a given applied bias. Efficient hydrogen generation...photogenerated holes in surface modified ?-Fe2O3 photoanodes for solar water splitting...

Monica Barroso; Camilo A. Mesa; Stephanie R. Pendlebury; Alexander J. Cowan; Takashi Hisatomi; Kevin Sivula; Michael Grtzel; David R. Klug; James R. Durrant

2012-01-01T23:59:59.000Z

445

Some remarks on black hole temperature and the second law of thermodynamics  

E-Print Network [OSTI]

I present a formulation of the second law of thermodynamics in the presence of black holes which makes use of the efficiency of an ideal machine extracting heat cyclically from a black hole. The Carnot coefficient is found and it is shown to be a simple function of the mass.

M. Scandurra

2001-05-24T23:59:59.000Z

446

Permanent Bubble Arrays from a Cross-Linked Poly(para-phenyleneethynylene): Picoliter Holes without Microfabrication  

E-Print Network [OSTI]

Permanent Bubble Arrays from a Cross-Linked Poly(para-phenyleneethynylene): Picoliter Holes without). The holes are formed by heating self-assembled bubble arrays (from 4) to 300 °C. They will be useful evaporating solvents generate hexagonally ordered bubble arrays when moist air is used to evaporate

Srinivasarao, Mohan

447

Foundations of Physics Letters, VoL 8, No. 6, 199.5 FIXING A HOLE  

E-Print Network [OSTI]

Foundations of Physics Letters, VoL 8, No. 6, 199.5 FIXING A HOLE F.A. Muller Utrecht University, Foundations of Science Department P.O. Box 80.000, 3508 TA Utrecht, The Netherlands e-mail: muller. The composition applies directly to the uni- verse. Keys: general relativity, hole argument, diffeomorphism

Seevinck, Michiel

448

CA-170-02-15 | Open Energy Information  

Open Energy Info (EERE)

CA-170-02-15 CA-170-02-15 Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home NEPA Document Collection for: CA-170-02-15 EA at Long Valley Caldera Geothermal Area for Geothermal/Exploration Basalt Canyon Slim Hole and Geothermal Well Exploration Projects General NEPA Document Info Energy Sector Geothermal energy Environmental Analysis Type EA Applicant Mammoth Pacific Consultant EMA Associates Geothermal Area Long Valley Caldera Geothermal Area Project Location California Project Phase Geothermal/Exploration Techniques Drilling Methods, Exploration Drilling, Exploratory Well, Slim Holes Time Frame (days) NEPA Process Time 77 Participating Agencies Lead Agency BLM Funding Agency none provided Managing District Office BLM Central California District Office

449

Role of vanadium pentoxide hole-extracting nanolayer in rubrene/C70-based small molecule organic solar cells  

Science Journals Connector (OSTI)

Vanadium pentoxide (V2O5) was inserted between the donor layer and the anode as a hole-extracting nanolayer. Compared with devices without a hole-extracting layer, short-circuit current density (JSC), open-circuit ...

Zhen Zhan, Jing Cao, Weiguang Xie, Lintao Hou, Qin Ye, Pengyi Liu

2014-01-01T23:59:59.000Z

450

Core Holes At Fort Bliss Area (Combs, Et Al., 1999) | Open Energy  

Open Energy Info (EERE)

source source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon » Core Holes At Fort Bliss Area (Combs, Et Al., 1999) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Core Holes At Fort Bliss Area (Combs, Et Al., 1999) Exploration Activity Details Location Fort Bliss Area Exploration Technique Core Holes Activity Date Usefulness not indicated DOE-funding Unknown Notes Drilling for the four holes followed the same general pattern: 1) set a conductor casing to a depth of 30-50', 2) drill - 6" hole through mostly sand/clay sedentary formations to 500-600', 3) set 4-1/2" surface casing at that depth 4) core HQ (3.89" dia.) mostly through limestone/dolornite or

451

Thermal Gradient Holes At Salt Wells Area (Bureau of Land Management, 2009)  

Open Energy Info (EERE)

Thermal Gradient Holes At Salt Wells Area (Bureau of Land Management, 2009) Thermal Gradient Holes At Salt Wells Area (Bureau of Land Management, 2009) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Thermal Gradient Holes At Salt Wells Area (Bureau of Land Management, 2009) Exploration Activity Details Location Salt Wells Geothermal Area Exploration Technique Thermal Gradient Holes Activity Date 2008 - 2008 Usefulness not indicated DOE-funding Unknown Exploration Basis Vulcan increased exploration efforts in the summer and fall of 2008, during which time the company drilled two temperature gradient holes (86-15 O on Pad 1 and 17-16 O on Pad 3); conducted seismic, gravity and magnetotelluric surveys; and drilled deep exploration wells at Pads 6 and 8 and binary wells at Pads 1, 2, 4, and 7. Notes

452

Core Hole Drilling And Testing At The Lake City, California Geothermal  

Open Energy Info (EERE)

Hole Drilling And Testing At The Lake City, California Geothermal Hole Drilling And Testing At The Lake City, California Geothermal Field Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Paper: Core Hole Drilling And Testing At The Lake City, California Geothermal Field Details Activities (4) Areas (1) Regions (0) Abstract: Unavailable Author(s): Dick Benoit, Joe Moore, Colin Goranson, David Blackwell Published: GRC, 2005 Document Number: Unavailable DOI: Unavailable Core Analysis At Lake City Hot Springs Area (Benoit Et Al., 2005) Core Holes At Lake City Hot Springs Area (Benoit Et Al., 2005) Flow Test At Lake City Hot Springs Area (Benoit Et Al., 2005) Static Temperature Survey At Lake City Hot Springs Area (Benoit Et Al., 2005) Lake City Hot Springs Geothermal Area Retrieved from "http://en.openei.org/w/index.php?title=Core_Hole_Drilling_And_Testing_At_The_Lake_City,_California_Geothermal_Field&oldid=389996

453

Core Holes At Lake City Hot Springs Area (Benoit Et Al., 2005) | Open  

Open Energy Info (EERE)

Holes At Lake City Hot Springs Area (Benoit Et Holes At Lake City Hot Springs Area (Benoit Et Al., 2005) Exploration Activity Details Location Lake City Hot Springs Area Exploration Technique Core Holes Activity Date Usefulness useful DOE-funding Unknown Notes Three core holes drilled between 2002 and 2005. Depths: 1,728; 3,435; 4,727 ft. Two deeper wells encountered temps of 327 and 329 oF and permable fractures in sedimentary and volcanic rocks; enabled injection and flow testing up to 70 gpm. Quartz fluid inclusions give temps of 264 and 316 oF. Core drillling allowed an understanding of geology and geothermal system that could never have been obtained from cuttings in this particular geologic setting. References Dick Benoit, Joe Moore, Colin Goranson, David Blackwell (2005) Core Hole Drilling And Testing At The Lake City, California Geothermal Field

454

Thermal Gradient Holes At Hot Springs Ranch Area (Szybinski, 2006) | Open  

Open Energy Info (EERE)

Thermal Gradient Holes At Hot Springs Ranch Area (Szybinski, 2006) Thermal Gradient Holes At Hot Springs Ranch Area (Szybinski, 2006) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Thermal Gradient Holes At Hot Springs Ranch Area (Szybinski, 2006) Exploration Activity Details Location Hot Springs Ranch Area Exploration Technique Thermal Gradient Holes Activity Date Usefulness useful DOE-funding Unknown Notes In 2005, Nevada Geothermal Power Company drilled four geothermal gradient wells, PVTG-1, -2, -3, and -4, and all four encountered geothermal fluids. The holes provided valuable water geochemistry, supporting the geothermometry results obtained from the hot springs and Magma well. The temperature data gathered from all the wells clearly indicates the presence of a major plume of thermal water centered on the Pumpernickel Valley

455

Thermal Gradient Holes At Northern Basin & Range Region (Pritchett, 2004) |  

Open Energy Info (EERE)

Gradient Holes At Northern Basin & Range Region (Pritchett, 2004) Gradient Holes At Northern Basin & Range Region (Pritchett, 2004) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Thermal Gradient Holes At Northern Basin & Range Region (Pritchett, 2004) Exploration Activity Details Location Northern Basin and Range Geothermal Region Exploration Technique Thermal Gradient Holes Activity Date Usefulness not useful DOE-funding Unknown Notes NOTE: These are theoretical/computer simulation tests of various methods on eight hypothetical 'model' basing-and-range geothermal systems. "The 300-meter heat flow holes are essentially useless for finding the "hidden" reservoirs. Clearly, the best results are obtained from the SP and MT surveys, with DC resistivity a close third. It is concluded that the best

456

COSO Geothermal Exploratory Hole No. 1, CGEH No. 1. Completion report.  

Open Energy Info (EERE)

COSO Geothermal Exploratory Hole No. 1, CGEH No. 1. Completion report. COSO Geothermal Exploratory Hole No. 1, CGEH No. 1. Completion report. (Coso Hot Springs KGRA) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Report: COSO Geothermal Exploratory Hole No. 1, CGEH No. 1. Completion report. (Coso Hot Springs KGRA) Details Activities (1) Areas (1) Regions (0) Abstract: Coso Geothermal Exploratory Hole No. 1 (CGEH No. 1) is the first deep exploratory hole drilled in the Coso Hot Springs area of Southeastern California. CGEH No. 1 was drilled to a depth of 4,845 ft in the central area of a large thermal anomaly and was a continuation of investigative work in that locale to determine the existence of a geothermal resource. The drilling and completion of CGEH No. 1 is described. Also included are the daily drilling reports, drill bit records, descriptions of the casing,

457

Raft River Geothermal Exploratory Hole No. 2, RRGE-2. Completion report |  

Open Energy Info (EERE)

Hole No. 2, RRGE-2. Completion report Hole No. 2, RRGE-2. Completion report Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Report: Raft River Geothermal Exploratory Hole No. 2, RRGE-2. Completion report Details Activities (1) Areas (1) Regions (0) Abstract: The Raft River Geothermal Exploratory Hole No. 2 (RRGE-2) is the second exploratory hole drilled in the Raft River Valley location of the Idaho Geothermal R and D Project for the purpose of determining the existence of hot water in quantities suitable for commercial power generation and nonelectric applications. This well was drilled to a depth of 6,543 feet below ground level to obtain additional geological information for evaluation of the deep geothermal reservoir system. The drilling and completion of RRGE-2 are described. The daily drilling

458

Physical-Property Measurements on Core Samples from Drill-Holes DB-1 and  

Open Energy Info (EERE)

Physical-Property Measurements on Core Samples from Drill-Holes DB-1 and Physical-Property Measurements on Core Samples from Drill-Holes DB-1 and DB-2, Blue Mountain Geothermal Prospect, North-Central Nevada Jump to: navigation, search OpenEI Reference LibraryAdd to library Report: Physical-Property Measurements on Core Samples from Drill-Holes DB-1 and DB-2, Blue Mountain Geothermal Prospect, North-Central Nevada Abstract N/A Author U.S. Geological Survey Published Publisher Not Provided, 2009 Report Number 2009-1022 DOI Not Provided Check for DOI availability: http://crossref.org Online Internet link for Physical-Property Measurements on Core Samples from Drill-Holes DB-1 and DB-2, Blue Mountain Geothermal Prospect, North-Central Nevada Citation U.S. Geological Survey. 2009. Physical-Property Measurements on Core Samples from Drill-Holes DB-1 and DB-2, Blue Mountain Geothermal Prospect,

459

Testing operations plan: Coso Geothermal Exploratory Hole No. 1 (CGEH-1) |  

Open Energy Info (EERE)

operations plan: Coso Geothermal Exploratory Hole No. 1 (CGEH-1) operations plan: Coso Geothermal Exploratory Hole No. 1 (CGEH-1) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Report: Testing operations plan: Coso Geothermal Exploratory Hole No. 1 (CGEH-1) Details Activities (1) Areas (1) Regions (0) Abstract: Coso Geothermal Exploratory Hole No. 1 (CGEH-1) was drilled to investigate the potential of the Coso Hot Springs Known Geothermal Resource Area (KGRA) in southeastern California. Detailed background information is contained in the drilling plan, Coso Geothermal Exploratory Hole No. 1 (CGEH-1), NVO-184, dated June 1977. The purpose of this supplement to NVO-184 is to establish a plan of operations for testing the resource after completion of well drilling activities. Major elements of this plan include

460

Magnetized black holes and black rings in the higher dimensional dilaton gravity  

E-Print Network [OSTI]

In this paper we consider magnetized black holes and black rings in the higher dimensional dilaton gravity. Our study is based on exact solutions generated by applying a Harrison transformation to known asymptotically flat black hole and black ring solutions in higher dimensional spacetimes. The explicit solutions include the magnetized version of the higher dimensional Schwarzschild-Tangherlini black holes, Myers-Perry black holes and five dimensional (dipole) black rings. The basic physical quantities of the magnetized objects are calculated. We also discuss some properties of the solutions and their thermodynamics. The ultrarelativistic limits of the magnetized solutions are briefly discussed and an explicit example is given for the $D$-dimensional magnetized Schwarzschild-Tangherlini black holes.

Stoytcho S. Yazadjiev

2005-11-21T23:59:59.000Z

Note: This page contains sample records for the topic "hydroprobe slim holes" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

The Black Hole Particle Accelerator as a Machine to make Baby Universes  

E-Print Network [OSTI]

General relativity predicts that the inner horizon of an astronomically realistic rotating black hole is subject to the mass inflation instability. The inflationary instability acts like a gravity-powered particle accelerator of extraordinary power, accelerating accreted streams of particles along the principal outgoing and ingoing null directions at the inner horizon to collision energies that would, if nothing intervened, typically exceed exponentially the Planck energy. The inflationary instability is fueled by ongoing accretion, and is occurring inevitably in essentially every black hole in our Universe. This extravagant machine, the Black Hole Particle Accelerator, has the hallmarks of a device to make baby universes. Since collisions are most numerous inside supermassive black holes, reproductive efficiency requires our Universe to make supermassive black holes efficiently, as is observed.

A. J. S. Hamilton

2013-05-20T23:59:59.000Z

462

Does the third law of black hole thermodynamics really have a serious failure?  

E-Print Network [OSTI]

The almost perfect correspondence between certain laws of classical black hole mechanics and the ordinary laws of thermodynamics is spoiled by the failure of the conventional back hole analogue of the third law. Our aim here is to contribute to the associated discussion by flashing light on some simple facts of black hole physics. However, no attempt is made to lay to rest the corresponding long lasting debate. Instead, merely some evidence is provided to make it clear that although the borderline between extremal and non-extremal black holes is very thin they are essentially different. Hopefully, a careful investigation of the related issues will end up with an appropriate form of the third law and hence with an unblemished setting of black hole thermodynamics.

Istvan Racz

2000-09-14T23:59:59.000Z

463

A Short Review of Relativistic Iron Lines from Stellar-Mass Black Holes  

E-Print Network [OSTI]

In this contribution, I briefly review recent progress in detecting and measuring the properties of relativistic iron lines observed in stellar-mass black hole systems, and the aspects of these lines that are most relevant to studies of similar lines in Seyfert-1 AGN. In particular, the lines observed in stellar-mass black holes are not complicated by complex low-energy absorption or partial-covering of the central engine, and strong lines are largely independent of the model used to fit the underlying broad-band continuum flux. Indeed, relativistic iron lines are the most robust diagnostic of black hole spin that is presently available to observers, with specific advantages over the systematics-plagued disk continuum. If accretion onto stellar-mass black holes simply scales with mass, then the widespread nature of lines in stellar-mass black holes may indicate that lines should be common in Seyfert-1 AGN, though perhaps harder to detect.

J. M. Miller

2006-09-15T23:59:59.000Z

464

Hole depletion of ladders in Sr14Cu24O41 induced by correlation effects  

Science Journals Connector (OSTI)

The hole distribution in Sr14Cu24O41 is studied by low-temperature polarization-dependent O K near-edge x-ray absorption fine-structure measurements and state-of-the-art electronic structure calculations that include core-hole and correlation effects in a mean-field approach. Contrary to all previous analysis, based on semiempirical models, we show that correlations and antiferromagnetic ordering favor the strong chain-hole attraction. For the remaining small number of holes accommodated on ladders, leg sites are preferred to rung sites. The small hole affinity of rung sites explains naturally the one-dimensional to two-dimensional crossover in the phase diagram of (La,Y,Sr,Ca)14Cu24O41.

V. Ilakovac; C. Gougoussis; M. Calandra; N. B. Brookes; V. Bisogni; S. G. Chiuzbaian; J. Akimitsu; O. Milat; S. Tomi?; C. F. Hague

2012-02-07T23:59:59.000Z

465

Evaluation of Coso Geothermal Exploratory Hole No. 1 (CGEH-1) Coso Hot  

Open Energy Info (EERE)

Coso Geothermal Exploratory Hole No. 1 (CGEH-1) Coso Hot Coso Geothermal Exploratory Hole No. 1 (CGEH-1) Coso Hot Springs: KGRA, China Lake, CA Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Proceedings: Evaluation of Coso Geothermal Exploratory Hole No. 1 (CGEH-1) Coso Hot Springs: KGRA, China Lake, CA Details Activities (1) Areas (1) Regions (0) Abstract: The well, Coso Geothermal Exploratory Hole No. 1 (CGEH-1) was drilled at the China Lake Naval Weapons Center. Drilling was started on 2 September 1977, and the well completed on 1 December 1977 to 4845 ft. The well is an exploratory hole to determine geological and hydrothermal characteristics of the Coso Hot Springs KGRA (Known Geothermal Resource Area). During drilling, numerous geophysical and temperature surveys were performed to evaluate the geological characteristics of CGEH-1. LBL

466

Thermal Gradient Holes At Lightning Dock Area (Cunniff & Bowers, 2005) |  

Open Energy Info (EERE)

Thermal Gradient Holes At Lightning Dock Area Thermal Gradient Holes At Lightning Dock Area (Cunniff & Bowers, 2005) Exploration Activity Details Location Lightning Dock Area Exploration Technique Thermal Gradient Holes Activity Date Usefulness not indicated DOE-funding Unknown Notes The two gradient holes were sited on federal geothermal leases owned by Lightning Dock Geothermal, Inc. and both were drilled into lakebed sediments some distance from the intense shallow geothermal anomaly located in the eastern half of Section 7, Township 25 South, Range 19 West. References Roy A. Cunniff, Roger L. Bowers (2005) Final Technical Report, Geothermal Resource Evaluation And Definitioni (Gred) Program-Phases I, Ii, And Iii For The Animas Valley, Nm Geothermal Resource Retrieved from "http://en.openei.org/w/index.php?title=Thermal_Gradient_Holes_At_Lightning_Dock_Area_(Cunniff_%26_Bowers,_2005)&oldid=387460"

467

Thermal Gradient Holes At Nw Basin & Range Region (Pritchett, 2004) | Open  

Open Energy Info (EERE)

Thermal Gradient Holes At Nw Basin & Range Region (Pritchett, 2004) Thermal Gradient Holes At Nw Basin & Range Region (Pritchett, 2004) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Thermal Gradient Holes At Nw Basin & Range Region (Pritchett, 2004) Exploration Activity Details Location Northwest Basin and Range Geothermal Region Exploration Technique Thermal Gradient Holes Activity Date Usefulness not useful DOE-funding Unknown Notes NOTE: These are theoretical/computer simulation tests of various methods on eight hypothetical 'model' basing-and-range geothermal systems. "The 300-meter heat flow holes are essentially useless for finding the "hidden" reservoirs. Clearly, the best results are obtained from the SP and MT surveys, with DC resistivity a close third. It is concluded that the best

468

S&TR | April 2007: Fire in the Hole  

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

Staff Staff Article title: Fire in the Hole; article blurb: Underground coal gasification may provide a secure energy supply and reduce greenhouse gas emissions. WORLDWIDE coal reserves are vast, over 10 trillion metric tons, but unless cleaner and cheaper ways can be found to convert coal to gas or liquid fuels, coal is unlikely to become an acceptable replacement for dwindling and uncertain supplies of oil and natural gas. Mining coal is dangerous work, coal is dirty to burn, and much of the coal in the ground is too deep or too low in quality to be mined economically. Today, less than one-sixth of the world's coal is economically accessible. However, Livermore is helping to revive an old technology that offers promise to substantially increase usable coal reserves and make coal a clean and economic

469

Thermal Gradient Holes At Hualalai Northwest Rift Area (Thomas, 1986) |  

Open Energy Info (EERE)

Hualalai Northwest Rift Hualalai Northwest Rift Area (Thomas, 1986) Exploration Activity Details Location Hualalai Northwest Rift Area Exploration Technique Thermal Gradient Holes Activity Date Usefulness not useful DOE-funding Unknown Notes Although not part of the current effort, two deep (approximately 2000 m) exploratory wells were drilled on the north flank of Hualalai near Puu Waawaa cinder cone. The geophysical data used for siting these wells were proprietary and hence unavailable for publication; however, the temperatures measured at the bottoms of the wells were reported to be below 20degrees C. Chemical analysis of water samples taken from these wells did not provide useful geothermal data due to contamination of the well water with drilling muds References Donald M. Thomas (1 January 1986) Geothermal Resources Assessment In

470

Alfven Wave Turbulence and Perpendicular Ion Temperatures in Coronal Holes  

E-Print Network [OSTI]

Low-frequency Alfven-wave turbulence causes ion trajectories to become chaotic, or "stochastic," when the turbulence amplitude is sufficiently large. Stochastic orbits enable ions to absorb energy from the turbulence, increasing the perpendicular ion temperature even when the fluctuation frequencies are too small for a cyclotron resonance to occur. In this paper, an analytic expression for the stochastic heating rate is used in conjunction with an observationally constrained turbulence model to obtain an analytic formula for the perpendicular ion temperature as a function of heliocentric distance r, ion mass, and ion charge in coronal holes for values of r between 2 and 15 solar radii (Rs). The resulting temperature profiles provide a good fit to observations of protons and OVI ions at 2Rs heating also offers a natural explanation for several detailed features of the UVCS observations, including the preferential and anisotropic h...

Chandran, Benjamin D G

2010-01-01T23:59:59.000Z

471

Moving Mirrors, Black Holes, Hawking Radiation and All That  

E-Print Network [OSTI]

In this talk I show how to canonically quantize a massless scalar field in the background of a Schwarzschild black hole in Lema\\^itre coordinates and then present a simplified derivation of Hawking radiation based upon this procedure. The key result of quantization procedure is that the Hamiltonian of the system is explicitly time dependent and so problem is intrinsically non-static. From this it follows that, although a unitary time-development operator exists, it is not useful to talk about vacuum states; rather, one should focus attention on steady state phenomena such as the Hawking radiation. In order to clarify the approximations used to study this problem I begin by discussing the related problem of the massless scalar field theory calculated in the presence of a moving mirror.

Marvin Weinstein

2001-11-09T23:59:59.000Z

472

Moving Mirrors, Black Holes, Hawking Radiation and All That  

E-Print Network [OSTI]

In this talk I show how to canonically quantize a massless scalar field in the background of a Schwarzschild black hole in Lema\\^itre coordinates and then present a simplified derivation of Hawking radiation based upon this procedure. The key result of quantization procedure is that the Hamiltonian of the system is explicitly time dependent and so problem is intrinsically non-static. From this it follows that, although a unitary time-development operator exists, it is not useful to talk about vacuum states; rather, one should focus attention on steady state phenomena such as the Hawking radiation. In order to clarify the approximations used to study this problem I begin by discussing the related problem of the massless scalar field theory calculated in the presence of a moving mirror.

Weinstein, M A

2002-01-01T23:59:59.000Z

473

Moving Mirrors, Black Holes, Hawking Radiation and All That  

SciTech Connect (OSTI)

In this talk I show how, in Lemaitre coordinates, one can canonically quantize a massless scalar field in the background of a Schwarzschild black hole and then show how this leads to a simplified derivation of Hawking radiation. The key result of the canonical quantization procedure is that the Hamiltonian of the system is explicitly time dependent, which immediately shows that the problem is intrinsically non-static and that, although a unitary time-development operator exists, it is not useful to talk about eigenstates. Rather, one should deal with the Heisenberg equations of motion and focus attention on steady state phenomena, such as the Hawking radiation. In order to clarify the procedure used to solve the Heisenberg equations I first discuss the related problem of the massless scalar field theory calculated in the presence of a moving mirror.

Weinstein, Marvin

2001-11-08T23:59:59.000Z

474

Dyons with potentials: Duality and black hole thermodynamics  

SciTech Connect (OSTI)

A modified version of the double potential formalism for the electrodynamics of dyons is constructed. Besides the two vector potentials, this manifestly duality invariant formulation involves four additional potentials, scalar potentials which appear as Lagrange multipliers for the electric and magnetic Gauss constraints and potentials for the longitudinal electric and magnetic fields. In this framework, a static dyon appears as a Coulomb-like solution without string singularities. Dirac strings are needed only for the Lorentz force law, not for Maxwell's equations. The magnetic charge no longer appears as a topological conservation law but as a surface integral on a par with electric charge. The theory is generalized to curved space. As in flat space, the string singularities of dyonic black holes are resolved. As a consequence all singularities are protected by the horizon and the thermodynamics is shown to follow from standard arguments in the grand canonical ensemble.

Barnich, Glenn; Gomberoff, Andres [Physique Theorique et Mathematique, Universite Libre de Bruxelles and International Solvay Institutes, Campus Plaine C.P. 231, B-1050 Bruxelles (Belgium); Universidad Nacional Andres Bello, Av. Republica 239, Santiago (Chile)

2008-07-15T23:59:59.000Z

475

Thermal Gradient Holes At Coso Geothermal Area (1974) | Open Energy  

Open Energy Info (EERE)

Coso Geothermal Area (1974) Coso Geothermal Area (1974) Exploration Activity Details Location Coso Geothermal Area Exploration Technique Thermal Gradient Holes Activity Date 1974 Usefulness useful DOE-funding Unknown Exploration Basis Use heat flow studies for the first time at Coso to indicate the presence or absence of abnormal heat Notes Located 10 sites for heat flow boreholes using available seismic ground noise and electrical resistivity data; data collected from 9 of 10; thermal conductivity measurements were completed using both the needle probe technique and the divided bar apparatus with a cell arrangement. In the upper few hundred meters of the subsurface heat is being transferred by a conductive heat transfer mechanism with a value of ~ 15 µcal/cm2sec; the background heat flow is ~ 3.5 HFU.

476

RECOILING SUPERMASSIVE BLACK HOLES IN SPIN-FLIP RADIO GALAXIES  

SciTech Connect (OSTI)

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

Liu, F. K.; Wang Dong [Department of Astronomy, Peking University, 100871 Beijing (China); Chen Xian, E-mail: fkliu@pku.edu.cn [Kavli Institute for Astronomy and Astrophysics, Peking University, 100871 Beijing (China)

2012-02-20T23:59:59.000Z

477

Black hole perturbation in parity violating gravitational theories  

SciTech Connect (OSTI)

We study linear perturbations around static, spherically symmetric spacetimes in f(R,C) gravitational theories whose Lagrangians depend on the Ricci scalar R and the parity violating Chern-Simons term C. By an explicit construction, we show that the Hamiltonian for the perturbation variables is not bounded from below, suggesting that such a background spacetime is unstable against perturbations. This gives a strong limit on a phenomenological gravitational model which violates parity. We also show that either R=const or ({partial_derivative}{sup 2}f/{partial_derivative}R{partial_derivative}C)=0 is a necessary and sufficient condition for the stability. We then implement in detail the perturbation analysis for such theories which satisfy the stability conditions. For l{>=}2, where l is the usual integer for the multipole expansion, the number of propagating modes is three, one from the odd and the other two from the even, all of which propagate at the speed of light. Unlike in the case of f(R) theories, these modes are coupled to each other, which can be used as a distinctive feature to test the parity violating theories from observations. The no-ghost conditions and no-tachyon conditions are the same as those in f(R) theories. For the dipole perturbations, the odd and the even modes completely decouple. The odd mode gives a slowly rotating black hole solution whose metric is linearized in its angular momentum. We provide an integral expression of this solution. On the other hand, the even mode propagates at the speed of light. For the monopole perturbation, in addition to a mode which simply shifts the mass of the background black hole, there also exists one even mode that propagates at the speed of light.

Motohashi, Hayato [Department of Physics, Graduate School of Science, University of Tokyo, Tokyo 113-0033 (Japan); Research Center for the Early Universe (RESCEU), Graduate School of Science, University of Tokyo, Tokyo 113-0033 (Japan); Suyama, Teruaki [Research Center for the Early Universe (RESCEU), Graduate School of Science, University of Tokyo, Tokyo 113-0033 (Japan)

2011-10-15T23:59:59.000Z

478

Supermassive black hole mass related to total mass of host galaxy  

E-Print Network [OSTI]

Although a supermassive black hole resides at the center of almost all galaxies, fundamental questions concerning the relation between central black hole mass and host galaxy mass remain unanswered. Marleau et al [arXiv:1212.0980 and arXiv:1411.3844] studied about 6,000 galaxies and found central black hole mass correlates better with total stellar mass of the host galaxy than with bulge mass, disk mass, or stellar velocity dispersion. They summarized their findings in a linear correlation equation linking central black hole mass and host galaxy stellar mass. The model outlined in this paper, based on the holographic principle and involving no arbitrary parameters, relates central black hole mass to total mass (including dark matter) of the host galaxy and accounts for the Marleau et al 6,000 galaxy survey data better than their linear correlation equation. The fact that a simple model with no arbitrary parameters accounts for observational data on central black holes in terms of host galaxy total mass reinforces the conclusion that central black holes are an essential element of most galaxies.

T. R. Mongan

2015-01-15T23:59:59.000Z

479

Influence of the back reaction of the Hawking radiation upon black hole quasinormal modes  

Science Journals Connector (OSTI)

We consider the BTZ black hole surrounded by the conformal scalar field. Within general relativity, the resonant quasinormal (QN) modes dominate in the response of a black hole to external perturbations. At the same time, the metric of an evaporating black hole is affected by the Hawking radiation. We estimate the shift in the quasinormal spectrum of the BTZ black hole stipulated by the back reaction of the Hawking radiation. For the case of the (2+1)-dimensional black hole the corrected (by ??) metric is an exact solution [C. Martines and J. Zanelli, Phys. Rev. D 55, 3642 (1997)]. In addition, in this case quantum corrections come only from matter fields and not from graviton loops, that is, one can solve the problem of influence of the back reaction upon the QN ringing self-consistently. The dominant contribution to the corrections to the QNMs is simply a shift of ?2 proportional to -(?/M)3/2(4L2+M)?. It is negligible for large black holes but essential for small ones, giving rise to considerable increasing of the quality factor. Thus, the small evaporating black hole is expected to be a much better oscillator than a large one.

R. A. Konoplya

2004-08-18T23:59:59.000Z

480

BPS-like bound and thermodynamics of the charged BTZ black hole  

SciTech Connect (OSTI)

The charged Banados-Teitelboim-Zanelli (BTZ) black hole is plagued by several pathologies: (a) Divergent boundary terms are present in the action; hence, we have a divergent black-hole mass. (b) Once a finite, renormalized, mass M is defined, black-hole states exist for arbitrarily negative values of M. (c) There is no upper bound on the charge Q. We show that these pathological features are an artifact of the renormalization procedure. They can be completely removed by using an alternative renormalization scheme leading to a different definition M{sub 0} of the black-hole mass, which is the total energy inside the horizon. The new mass satisfies a BPS-like bound M{sub 0}{>=}({pi}/2)Q{sup 2}, and the heat capacity of the hole is positive. We also discuss the black-hole thermodynamics that arises when M{sub 0} is interpreted as the internal energy of the system. We show, using three independent approaches (black-hole thermodynamics, Einstein equations, and Euclidean action formulation), that M{sub 0} satisfies the first law if a term describing the mechanical work done by the electrostatic pressure is introduced.

Cadoni, Mariano; Monni, Cristina [Dipartimento di Fisica, Universita di Cagliari and INFN, Sezione di Cagliari, Cittadella Universitaria, 09042 Monserrato (Italy)

2009-07-15T23:59:59.000Z

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481

Temperature, Energy, and Heat Capacity of Asymptotically Anti-De Sitter Black Holes  

E-Print Network [OSTI]

We investigate the thermodynamical properties of black holes in (3+1) and (2+1) dimensional Einstein gravity with a negative cosmological constant. In each case, the thermodynamic internal energy is computed for a finite spatial region that contains the black hole. The temperature at the boundary of this region is defined by differentiating the energy with respect to entropy, and is equal to the product of the surface gravity (divided by~$2\\pi$) and the Tolman redshift factor for temperature in a stationary gravitational field. We also compute the thermodynamic surface pressure and, in the case of the (2+1) black hole, show that the chemical potential conjugate to angular momentum is equal to the proper angular velocity of the black hole with respect to observers who are at rest in the stationary time slices. In (3+1) dimensions, a calculation of the heat capacity reveals the existence of a thermodynamically stable black hole solution and a negative heat capacity instanton. This result holds in the limit that the spatial boundary tends to infinity only if the comological constant is negative; if the cosmological constant vanishes, the stable black hole solution is lost. In (2+1) dimensions, a calculation of the heat capacity reveals the existence of a thermodynamically stable black hole solution, but no negative heat capacity instanton.

J. D. Brown; J. Creighton; R. B. Mann

1994-05-03T23:59:59.000Z

482

Persistent spectral-hole-burning spectroscopy of CuCl quantum cubes  

Science Journals Connector (OSTI)

A persistent spectral-hole-burning (PSHB) phenomenon was successfully applied to the precise site-selective spectroscopy of CuCl quantum dots embedded in NaCl crystals. In the PSHB spectra of CuCl quantum dots, a resonantly burned hole and lower-energy satellite holes were observed. These satellite holes are supposed to originate from hole burning of the ground states, which results from site-selective excitation of the corresponding excited states of excitons confined in CuCl quantum dots. Energy relation between the resonantly burned hole and each satellite hole is well explained by the simple concept of a particle in a quantum cube with an infinitely high potential barrier. However, actual quantum dots are considered to be a little deviated from cubes, resulting in the violation of the optical selection rule in quantum cubes. A cubic-shaped quantum-dot model is almost consistent with oscillatory fine structures observed in the Z3 exciton absorption band. Its spectral decomposition into the ground state and the first excited state of excitons was made, and showed that the first excited state is in majority at the higher-energy region of the Z3 exciton absorption band. This result was supported by the photoluminescence spectrum of the Z3 exciton.

Naru Sakakura and Yasuaki Masumoto

1997-08-15T23:59:59.000Z

483

Flame structure of wall-impinging diesel fuel sprays injected by group-hole nozzles  

SciTech Connect (OSTI)

This paper describes an investigation of the flame structure of wall-impinging diesel sprays injected by group-hole nozzles in a constant-volume combustion vessel at experimental conditions typical of a diesel engine. The particular emphasis was on the effect of the included angle between two orifices (0-15 deg. in current study) on the flame structure and combustion characteristics under various simulated engine load conditions. The laser absorption scattering (LAS) technique was applied to analyze the spray and mixture properties. Direct flame imaging and OH chemiluminescence imaging were utilized to quantify the ignition delay, flame geometrical parameters, and OH chemiluminescence intensity. The images show that the asymmetric flame structure emerges in wall-impinging group-hole nozzle sprays as larger included angle and higher engine load conditions are applied, which is consistent with the spray shape observed by LAS. Compared to the base nozzle, group-hole nozzles with large included angles yield higher overall OH chemiluminescence intensity, wider flame area, and greater proportion of high OH intensity, implying the better fuel/air mixing and improved combustion characteristics. The advantages of group-hole nozzle are more pronounced under high load conditions. Based on the results, the feasibility of group-hole nozzle for practical direct injection diesel engines is also discussed. It is concluded that the asymmetric flame structure of a group-hole nozzle spray is favorable to reduce soot formation over wide engine loads. However, the hole configuration of the group-hole nozzle should be carefully considered so as to achieve proper air utilization in the combustion chamber. Stoichiometric diesel combustion is another promising application of group-hole nozzle. (author)

Gao, Jian; Moon, Seoksu; Nishida, Keiya; Matsumoto, Yuhei [Department of Mechanical System Engineering, University of Hiroshima, Higashi-Hiroshima, 739-8527 (Japan); Zhang, Yuyin [Department of Mechanical Engineering, Tokyo Denki University, Tokyo, 101-8457 (Japan)

2009-06-15T23:59:59.000Z

484

Chemical aspects of cylinder corrosion and a scenario for hole development  

SciTech Connect (OSTI)

In June 1990, two cylinders in the depleted UF{sub 6} cylinder storage yards at Portsmouth were discovered to have holes in their walls at the valve-end stiffening ring at a point below the level of the gas-solid interface of the UF{sub 6}. The cylinder with the larger hole, which extended under the stiffening ring, was stacked in a top row 13 years ago. The cylinder with the smaller hole had been stacked in a bottom row 4 years ago. The lifting lugs of the adjacent cylinders pointed directly at the holes. A Cylinder Investigating Committee was appointed to determine the cause or causes of the holes and to assess the implications of these findings. This report contains a listing of the chemically related facts established by the Investigating Committee with the cooperation of the Operations and Technical Support Divisions at the Portsmouth Gaseous Diffusion Plant, the scenario developed to explain these findings and some implications of this scenario. In summary, the interrelated reactions of water, solid UF{sub 6} and iron presented by R. L. Ritter are used to develop a scenario which explains the observations and deductions made during the investigation. The chemical processes are intimately related to the course of the last three of the four stages of hole development. A simple model is proposed which permits semiquantitative prediction of such information as the HF loss rates as a function of time, the rate of hole enlargement, the time to hydrolyze a cylinder of UF{sub 6} and the approximate size of the hole. The scenario suggests that the environmental consequences associated with a developing hole in a depleted UF{sub 6} cylinder are minimal for the first several years but will become significant if too many years pass before detection. The overall environmental picture is presented in more detail elsewhere.

Barber, E.J. [Martin Marietta Energy Systems, Oak Ridge, TN (United States)

1991-12-31T23:59:59.000Z

485

Thermal Gradient Holes At Blue Mountain Area (Fairbank & Neggemann, 2004) |  

Open Energy Info (EERE)

Blue Mountain Area (Fairbank & Neggemann, 2004) Blue Mountain Area (Fairbank & Neggemann, 2004) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Thermal Gradient Holes At Blue Mountain Area (Fairbank & Neggemann, 2004) Exploration Activity Details Location Blue Mountain Area Exploration Technique Thermal Gradient Holes Activity Date Usefulness useful DOE-funding Unknown References Brian D. Fairbank, Kim V. Niggemann (2004) Deep Blue No 1- A Slimhole Geothermal Discovery At Blue Mountain, Humboldt County, Nevada Retrieved from "http://en.openei.org/w/index.php?title=Thermal_Gradient_Holes_At_Blue_Mountain_Area_(Fairbank_%26_Neggemann,_2004)&oldid=386709" Category: Exploration Activities What links here Related changes Special pages Printable version Permanent link

486

Mass and First Law for Static Asymptotically Randall-Sundrum Black Holes  

E-Print Network [OSTI]

We give a new, intrinsic, mass definition for spacetimes asymptotic to the Randall-Sundrum braneworld models, RS1 and RS2. For this mass, we prove a first law for static black holes, including variations of the bulk cosmological constant, brane tensions, and RS1 interbrane distance. Our first law defines a thermodynamic volume and a gravitational tension that are braneworld analogs of the corresponding quantities in asymptotically AdS black hole spacetimes and asymptotically flat compactifications, respectively. This paper is the first in a series on asymptotically RS black holes.

Scott Fraser; Douglas M. Eardley

2014-09-04T23:59:59.000Z

487

SiGe quantum dots for fast hole spin Rabi oscillations  

SciTech Connect (OSTI)

We report on hole g-factor measurements in three terminal SiGe self-assembled quantum dot devices with a top gate electrode positioned very close to the nanostructure. Measurements of both the perpendicular as well as the parallel g-factor reveal significant changes for a small modulation of the top gate voltage. From the observed modulations, we estimate that, for realistic experimental conditions, hole spins can be electrically manipulated with Rabi frequencies in the order of 100?MHz. This work emphasises the potential of hole-based nano-devices for efficient spin manipulation by means of the g-tensor modulation technique.

Ares, N.; Prager, A.; De Franceschi, S. [SPSMS/LaTEQS, CEA-INAC/UJF-Grenoble 1, 17 Rue des Martyrs, 38054 Grenoble Cedex 9 (France)] [SPSMS/LaTEQS, CEA-INAC/UJF-Grenoble 1, 17 Rue des Martyrs, 38054 Grenoble Cedex 9 (France); Katsaros, G. [SPSMS/LaTEQS, CEA-INAC/UJF-Grenoble 1, 17 Rue des Martyrs, 38054 Grenoble Cedex 9 (France) [SPSMS/LaTEQS, CEA-INAC/UJF-Grenoble 1, 17 Rue des Martyrs, 38054 Grenoble Cedex 9 (France); Institute for Integrative Nanosciences, IFW Dresden, Helmholtzstr. 20, D-01069 Dresden (Germany); Johannes Kepler University, Institute of Semiconductor and Solid State Physics, Altenbergerstr. 69, 4040 Linz (Austria); Golovach, V. N. [Institute for Integrative Nanosciences, IFW Dresden, Helmholtzstr. 20, D-01069 Dresden (Germany) [Institute for Integrative Nanosciences, IFW Dresden, Helmholtzstr. 20, D-01069 Dresden (Germany); Centro de Fsica de Materiales CFM/MPC (CSIC-UPV/EHU) and Donostia International Physics Center DIPC, E-20018 San Sebastin (Spain); IKERBASQUE, Basque Foundation for Science, E-48011 Bilbao (Spain); Zhang, J. J. [Institute for Integrative Nanosciences, IFW Dresden, Helmholtzstr. 20, D-01069 Dresden (Germany)] [Institute for Integrative Nanosciences, IFW Dresden, Helmholtzstr. 20, D-01069 Dresden (Germany); Glazman, L. I. [Department of Physics, Yale University, New Haven, Connecticut 06520 (United States)] [Department of Physics, Yale University, New Haven, Connecticut 06520 (United States); Schmidt, O. G. [Institute for Integrative Nanosciences, IFW Dresden, Helmholtzstr. 20, D-01069 Dresden (Germany) [Institute for Integrative Nanosciences, IFW Dresden, Helmholtzstr. 20, D-01069 Dresden (Germany); Center for Advancing Electronics Dresden, TU Dresden (Germany)

2013-12-23T23:59:59.000Z

488

Ion Feedback Suppression Using Inclined MCP Holes in a _Single-MCP+Micromegas+Pads_ Detector  

SciTech Connect (OSTI)

We show that the ion backflow to photocathode can be completely suppressed if one uses inclined MCP holes in a presence of magnetic field. The inclined hole angles are chosen to be aligned with the Lorentz electron angle allowing the electron transmission and amplification, while positive ions, traveling along a different angle, are caught on the MCP hole walls. The detector under investigation is a new gaseous detector structure based on a tandem of two parts, a single MCP (Microchannel) plate, a Micromegas with pad readout. We are aiming to develop a gaseous photon detector with the Bialkali photocathode, however, one could use some ideas in the paper for other types of detectors.

Va'vra, J.; /SLAC; Sumiyoshi, T.; /Tokyo Metropolitan U.

2005-09-30T23:59:59.000Z

489

U(N)-monopoles on Kerr black hole and its entropy  

E-Print Network [OSTI]

We describe U(N)-monopoles (N > 1) on Kerr black holes by the parameters of the moduli space of holomorphic vector U(N)-bundles over two-sphere with the help of the Grothendieck splitting theorem. For N = 2,3 we obtain this description in an explicit form as well as the estimates for the corresponding monopole masses. This gives a possibility to adduce some reasonings in favour of existence of both a fine structure for Kerr black holes and the statistical ensemble tied with it which might generate the Kerr black hole entropy.

Yu. P. Goncharov

1998-06-04T23:59:59.000Z

490

Nano-electron beam induced current and hole charge dynamics through uncapped Ge nanocrystals  

SciTech Connect (OSTI)

Dynamics of hole storage in spherical Ge nanocrystals (NCs) formed by a two step dewetting/nucleation process on an oxide layer grown on an n-doped <001> silicon substrate is studied using a nano-electron beam induced current technique. Carrier generation is produced by an electron beam irradiation. The generated current is collected by an atomic force microscope--tip in contact mode at a fixed position away from the beam spot of about 0.5 {mu}m. This distance represents the effective diffusion length of holes. The time constants of holes charging are determined and the effect of the NC size is underlined.

Marchand, A.; El Hdiy, A.; Troyon, M. [Laboratoire de Recherche en Nanosciences, Bat. 6, case no 15, UFR Sciences, Universite de Reims Champagne Ardenne, 51687 Reims Cedex 2 (France); Amiard, G.; Ronda, A.; Berbezier, I. [IM2NP, Faculte des Sciences et Techniques, Campus de Saint Jerome - Case 142, Avenue Escadrille Normandie Niemen, 13397 Marseille Cedex 20 (France)

2012-04-16T23:59:59.000Z

491

General Nonextremal Rotating Charged Goedel Black Holes in Minimal Five-Dimensional Gauged Supergravity  

SciTech Connect (OSTI)

I present the general exact solutions for nonextremal rotating charged black holes in the Goedel universe of five-dimensional minimal supergravity theory. They are uniquely characterized by four nontrivial parameters: namely, the mass m, the charge q, the Kerr equal rotation parameter a, and the Goedel parameter j. I calculate the conserved energy, angular momenta, and charge for the solutions and show that they completely satisfy the first law of black hole thermodynamics. I also study the symmetry and separability of the Hamilton-Jacobi and the massive Klein-Gordon equations in these Einstein-Maxwell-Chern-Simons-Goedel black hole backgrounds.

Wu Shuangqing [College of Physical Science and Technology, Central China Normal University, Wuhan, Hubei 430079 (China)

2008-03-28T23:59:59.000Z

492

Using radio emission to detect isolated and quiescent accreting black holes  

E-Print Network [OSTI]

We discuss the implications of new relations between black holes' masses, X-ray luminosities and radio luminosities, as well as the properties of the next generation of radio telescopes, for the goal of finding isolated accreting black holes. Because accreting black holes have radio-to-X-ray flux ratios that increase with decreasing luminosity in Eddington units, and because deep surveys over large fields of view should be possible with planned instrumentation such as LOFAR, radio surveys should be significantly more efficient than X-ray surveys for finding these objects.

Thomas J. Maccarone

2005-03-05T23:59:59.000Z

493

Distinguishing causal time from Minkowski time and a model for the black hole quantum eigenstates  

E-Print Network [OSTI]

A discussion is presented of the principle of black hole com- plementarity. It is argued that this principle could be viewed as a breakdown of general relativity, or alternatively, as the introduction of a time variable with multiple `sheets' or `branches' A consequence of the theory is that the stress-energy tensor as viewed by an outside observer is not simply the Lorentz-transform of the tensor viewed by an ingoing observer. This can serve as a justification of a new model for the black hole atmosphere, recently re-introduced. It is discussed how such a model may lead to a dynamical description of the black hole quantum states.

G. 't Hooft

1997-11-18T23:59:59.000Z

494

Electromagnetic partner of the gravitational signal during accretion onto black holes  

E-Print Network [OSTI]

We investigate the generation of electromagnetic and gravitational radiation in the vicinity of a perturbed Schwarzschild black hole. The gravitational perturbations and the electromagnetic field are studied by solving the Teukolsky master equation with sources, which we take to be locally charged, radially infalling, matter. Our results show that, in addition to the gravitational wave generated as the matter falls into the black hole, there is also a burst of electromagnetic radiat