National Library of Energy BETA

Sample records for included white black

  1. I am Black AND Jewish: Black Jewish Women’s Experiences in “White” Jewish Communities in Brazil

    E-Print Network [OSTI]

    Gondek, Abby S.

    2008-01-01

    ideal after scientific racism. Black into white: Race andbut continues to enact racism and anti-Semitism (Barcelos,context demonstrates why racism (including anti-Semitism) is

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

    E-Print Network [OSTI]

    Wilson, Misty Michelle

    2009-05-15

    While a great deal of sociological and psychological research has been done on black-white interracial couples and the challenges they have faced in past eras, the communication between the partners remains largely ...

  3. Black Kernel and White Tip of Rice. 

    E-Print Network [OSTI]

    Martin, Alan L. (Alan La Mott); Altstatt, G. E. (George E.)

    1940-01-01

    . Amer. Jour. Bot. 26 :P46-852. 1939. Taubenhaus, J. J. Rice diseases. In 50th Ann. Rpt. Tex. Agr. Sta., pp. 114-115. 1937. Taubenhaus, J. J., Altstatt, G. E., and Wyche, R. H. Black kernel of rice. In 4Fth Ann. Rpt. Texas Am. Exp. Sta., p. 94. 1935.... Taubenhaus, J. J., and Wyche, R. H. Rice Diseases. In 49th Ann. Rpt. Texas Agr. Exp. Sta., pp. 109-111. 1936. Tullis, E. C. Fungi isolated from discolored rice kernels. U. S. Dept. Agr. Tech. Bull. 540. 1936. ...

  4. Analysis of the Black-capped Vireo and White-eyed Vireo Nest Predator assemblages 

    E-Print Network [OSTI]

    Conkling, Tara J.

    2011-08-08

    Predation is the leading cause of nest failure in songbirds. My study identified nest predators of black-capped vireos and white-eyed vireos, quantified the activity of potential predator species, examined the relationships between vegetation...

  5. HEPATIC MINERALS OF WHITE-TAILED AND MULE DEER IN THE SOUTHERN BLACK HILLS, SOUTH DAKOTA

    E-Print Network [OSTI]

    HEPATIC MINERALS OF WHITE-TAILED AND MULE DEER IN THE SOUTHERN BLACK HILLS, SOUTH DAKOTA Teresa J status, and species. Key words: Black Hills, elements, fire, liver, mule deer, Odocoileus hemionus and laboratory animals (Robbins, 1983). Liver concentrations of some trace elements have been measured in elk

  6. The pulmonary response of white and black adults to six concentrations of ozone

    SciTech Connect (OSTI)

    Seal, E. Jr.; McDonnell, W.F.; House, D.E.; Salaam, S.A.; Dewitt, P.J.; Butler, S.O.; Green, J.; Raggio, L. )

    1993-04-01

    Many early studies of respiratory responsiveness to ozone (O3) were done on healthy, young, white males. The purpose of this study was to determine whether gender or race differences in O3 response exist among white and black, males and females, and to develop concentration-response curves for each of the gender-race groups. Three hundred seventy-two subjects (n > 90 in each gender-race group), ages 18 to 35 yr, were exposed once for 2.33 h to 0.0 (purified air), 0.12, 0.18, 0.24, 0.30, or 0.40 ppm O3. Each exposure was preceded by baseline pulmonary function tests and a symptom questionnaire. The first 2 h of exposure included alternating 15-min periods of rest and exercise on a motorized treadmill producing a minute ventilation (VE) of 25 L/min/m2 body surface area (BSA). After exposure, subjects completed a set of pulmonary function tests and a symptom questionnaire. Lung function and symptom responses were expressed as percent change from baseline and analyzed using a nonparametric two factor analysis of variance. Three primary variables were analyzed: FEV1, specific airway resistance (SRaw), and cough. Statistical analysis demonstrated no significant differences in response to O3 among the individual gender-race groups. For the group as a whole, changes in the variables FEV1, SRaw, and cough were first noted at 0.12, 0.18, and 0.18 ppm O3, respectively. Adjusted for exercise difference, concentration-response curves for FEV1 and cough among white males were consistent with previous reports (1).

  7. I would like all figures in my article published in Black and White Education in Brazil

    E-Print Network [OSTI]

    Barbosa, Marcia C. B.

    I would like all figures in my article published in Black and White Education in Brazil: Marcia C Postal 15051 91501970, Porto Alegre, RS, Brazil marcia. barbosa@ufrgs.br Keywords Gender, Physics, Brazil Abstract An overview of the Brazilian educational system is presented with the main

  8. White Noise, Black-body radiation and Secure communication

    E-Print Network [OSTI]

    C. Tannous; J. Langlois

    2015-06-05

    Nyquist White noise derivation based on blackbody radiation interacting with electrons in a transmission line is revisited and is shown to possibly pave the way toward secure noise-based communication systems. Encrypting a message for secure transmission might be performed by combining it with controlled noise as performed in Spread-Spectrum communication that are presently used in Telecommunication systems. Quantum communication using entanglement is another route for secure communications as demonstrated by several important experiments. Classical and Quantum noise are compared and discussed as a major constituent of secure communication.

  9. The effects of chemical toners on cold and warm tone photographic black and white fiber base enlarging papers

    E-Print Network [OSTI]

    Rantoul, Micaela Garzoni

    1983-01-01

    What this thesis attempts to present is a systematic and ordered assembling of different true chemical toners on two types of black and white enlarging papers with two different developers. It is my hope that this study ...

  10. Athletic behavior and achievement orientations of female adolescents: a black-white comparative analysis 

    E-Print Network [OSTI]

    Butler, James A

    1976-01-01

    Cha1rman of Advisory Comm1ttee: Dr. J. Steven Picou The primary objective of th1s thesis was to determine the rela- tionsh1p between athletic participation and female ach1evement orien- tations. Spec1f1cally, the study focused on the relat1onship... was that black females, both athletes and nonathletes, had stronger materialist1c orientations and were more willing to defer grat1f1cation for future career achievements than the1r white counter- parts. The theoretical implications of these results...

  11. Examining the Relationship Between Minority Status Stress, the Social Change Model of Leadership Development, and Persistence of Black Students at Predominantly White Institutions 

    E-Print Network [OSTI]

    Brown, Lesley-Ann

    2012-10-19

    Minority status stress, which is the stress Black college students experience at predominantly White institutions (PWIs) as a result of their racial minority status, has been found to negatively impact their persistence in college. Two manuscripts...

  12. An analysis of the performance of black and white retardates on the Wechsler Intelligence Scale for children 

    E-Print Network [OSTI]

    Thompson, Catherine Phillips

    1972-01-01

    AND STANDARD DEVIATIONS OF BLACK AND WHITE RETARDATES ON WISC SUBTESTS AND FULL SCALE IQ PAGE 32 33 36 38 5 ANALYSIS OF VARIANCE FOR VOCABULARY SUBTEST ANALYSIS OF VARIANCE FOR PICTURE ARRANGE SUBTEST ANALYSIS OF VARIANCE FOR DIGIT SPAN SUBTEST 39... DEVIATIONS OF THREE AGE GROUPS ON WISC SUBTESTS AND FULL SCALE IQ ANALYSIS OF VARIANCE FOR INFORMATION SUBTEST. ANALYSIS OF VARIANCE FOR COMPREHENSION SUBTEST. ANALYSIS OF VARIANCE FOR ARITHMETIC SUBTEST ANALYSIS OF VARIANCE FOR SIMILARITIES SUBTEST...

  13. Illuminating Massive Black Holes With White Dwarfs: Orbital Dynamics and High Energy Transients from Tidal Interactions

    E-Print Network [OSTI]

    MacLeod, Morgan; Ramirez-Ruiz, Enrico; Guillochon, James; Samsing, Johan

    2014-01-01

    White dwarfs (WDs) can be tidally disrupted only by massive black holes (MBHs) with masses less than approximately $10^5 M_\\odot$. These tidal interactions feed material to the MBH well above its Eddington limit, with the potential to launch a relativistic jet. The corresponding beamed emission is a promising signpost to an otherwise quiescent MBH of relatively low mass. We show that the mass transfer history, and thus the lightcurve, are quite different when the disruptive orbit is parabolic, eccentric, or circular. The mass lost each orbit exponentiates in the eccentric-orbit case leading to the destruction of the WD after several tens of orbits and making it difficult to produce a Swift J1644+57-like lightcurve via this channel. We then examine the stellar dynamics of clusters surrounding these MBHs to show that single-passage WD disruptions are substantially more common than repeating encounters in eccentric orbits. The $10^{49}$ erg s$^{-1}$ peak luminosity of these events makes them visible to cosmologi...

  14. I am Black AND Jewish: Black Jewish Women’s Experiences in “White” Jewish Communities in Brazil

    E-Print Network [OSTI]

    Gondek, Abby S.

    2008-01-01

    the contemporary black movement in Brazil. In R. Reichmann (Race in contemporary Brazil (pp. 155-166). University Park,J.J. Crocitti (Eds. ), The Brazil reader: History, culture,

  15. Facies and Reservoir Characterization of the Permian White Rim Sandstone, Black Box Dolomite, and Black Dragon Member of the Triassic

    E-Print Network [OSTI]

    Seamons, Kent E.

    of Geological Sciences, BYU Master of Science Geologic sequestration of anthropogenic carbon dioxide (CO2, and Black Dragon Member of the Triassic Moenkopi Formation for CO2 Storage and Sequestration at Woodside Formation, for CO2 Sequestration at Woodside Field, East-central Utah Walter Harston Department

  16. Health in black and white : debates on racial and ethnic health disparities in Brazil

    E-Print Network [OSTI]

    Pagano, Anna

    2011-01-01

    Valle 1985 Updating the Cost of Not Being White in Brazil.Race, class, and power in Brazil. P. -M. Fontaine, ed. Pp.Ideas and Social Policy in Brazil, 1870-1940. In The Idea of

  17. October 2010 Features | News | Media | Events Business, Science, and Technology Black Faces in White

    E-Print Network [OSTI]

    October 2010 Features | News | Media | Events Business, Science, and Technology Black Faces programs. RSVP online | mba.rutgers.edu Follow RBS: RBS Quick Links Highlights Newsletters Faculty blogs Foundation. News More news at business.rutgers.edu/news MBA blog launched to share the real Rutgers MBA

  18. SWIFT J1644+57: A WHITE DWARF TIDALLY DISRUPTED BY A 10{sup 4} M{sub Sun} BLACK HOLE?

    SciTech Connect (OSTI)

    Krolik, Julian H.; Piran, Tsvi E-mail: tsvi@phys.huji.ac.il

    2011-12-20

    We propose that the remarkable object Swift J1644+57, in which multiple recurring hard X-ray flares were seen over a span of several days, is a system in which a white dwarf was tidally disrupted by an intermediate-mass black hole. Disruption of a white dwarf rather than a main-sequence star offers a number of advantages in understanding the multiple, and short, timescales seen in the light curve of this system. In particular, the short internal dynamical timescale of a white dwarf offers a more natural way of understanding the short rise times ({approx}100 s) observed. The relatively long intervals between flares ({approx}5 Multiplication-Sign 10{sup 4} s) may also be readily understood as the period between successive pericenter passages of the remnant white dwarf. In addition, the expected jet power is larger when a white dwarf is disrupted. If this model is correct, the black hole responsible must have a mass {approx}< 10{sup 5} M{sub Sun }.

  19. Optical Thermonuclear Transients From Tidal Compression of White Dwarfs as Tracers of the Low End of the Massive Black Hole Mass Function

    E-Print Network [OSTI]

    MacLeod, Morgan; Ramirez-Ruiz, Enrico; Kasen, Daniel; Rosswog, Stephan

    2015-01-01

    In this paper, we model the observable signatures of tidal disruptions of white dwarf (WD) stars by massive black holes (MBHs) of moderate mass, $\\approx 10^3 - 10^5 M_\\odot$. When the WD passes deep enough within the MBH's tidal field, these signatures include thermonuclear transients from burning during maximum compression. We combine a hydrodynamic simulation that includes nuclear burning of the disruption of a $0.6 M_\\odot$ C/O WD with a Monte Carlo radiative transfer calculation to synthesize the properties of a representative transient. The transient's emission emerges in the optical, with lightcurves and spectra reminiscent of type I SNe. The properties are strongly viewing-angle dependent, and key spectral signatures are $\\approx 10,000$ km s$^{-1}$ Doppler shifts due to the orbital motion of the unbound ejecta. Disruptions of He WDs likely produce large quantities of intermediate-mass elements, offering a possible production mechanism for Ca-rich transients. Accompanying multiwavelength transients ar...

  20. CONTENT ANR @ MSU AgBioResearch 1999 White Mold Ratings in Huron County, Tom Haag Farm

    E-Print Network [OSTI]

    Videos Links 1999 White Mold Ratings in Huron County, Tom Haag Farm NAVY White Mold Rating BLACK White Mold

  1. Iron line profiles including emission from within the innermost stable orbit of a black hole accretion disc

    E-Print Network [OSTI]

    A. J. Young; R. R. Ross; A. C. Fabian

    1998-08-10

    Reynolds & Begelman (1997) have recently proposed a model in which the broad and extremely redshifted iron line seen during a deep minimum of the light curve of the Seyfert 1 galaxy MCG-6-30-15 originates from matter spiralling into a Schwarzschild black hole, contrary to previous claims that the black hole may be spinning rapidly (Iwasawa et al 1996; Dabrowski et al 1997). Here we calculate in detail the X-ray spectrum produced by their model using the full reflected continuum emission, including absorption features. This calculation takes into account the doppler and relativistic effects. For the range of parameters we consider, we find that the spectrum should show a large photoelectric absorption edge of iron, which is not seen in the data. The absorption edge is a consequence of the line emitting matter within the innermost stable orbit being highly ionized, and is largely independent of the parameters chosen for their model. If we restrict our attention to the 3-10 keV band we may effectively remove this absorption edge by fitting a steeper power law, but this results in a significant underprediction of the 0.4-0.5 keV flux. We conclude that the data on MCG-6-30-15 are more consistent with the Kerr than the Schwarzschild model.

  2. Intersectionality and the Perpetuation of White Male Power through Interracial Sexual Violence 

    E-Print Network [OSTI]

    Feinstein, Rachel Anne

    2014-04-02

    The purpose of this dissertation research is to investigate the reactions and attitudes of white men, white women, black men, and black women to the sexual violence of enslaved black women carried out by white men. Using an intersectional approach...

  3. An Analysis of Three White Male High School Assistant Principal Perceptions of Black Males Students in a Suburban District 

    E-Print Network [OSTI]

    Ragsdale, Laura Anne

    2013-05-09

    thinking, but there is no research on assistant principals, who are arguably one of the most influential persons for at-risk students, therefore, as in the case of this study, for Black males. Perceptions of Black males inside and outside of school may...

  4. White Roofs

    ScienceCinema (OSTI)

    Chu, Steven

    2013-05-29

    Secretary Steven Chu discusses the benefits of switching to white roofs and light colored pavements.

  5. Prices include compostable serviceware and linen tablecloths

    E-Print Network [OSTI]

    California at Davis, University of

    APPETIZERS Prices include compostable serviceware and linen tablecloths for the food tables.ucdavis.edu. BUTTERNUT SQUASH & BLACK BEAN ENCHILADAS #12;BUFFETS Prices include compostable serviceware and linen

  6. White light velocity interferometer

    DOE Patents [OSTI]

    Erskine, D.J.

    1999-06-08

    The invention is a technique that allows the use of broadband and incoherent illumination. Although denoted white light velocimetry, this principle can be applied to any wave phenomenon. For the first time, powerful, compact or inexpensive sources can be used for remote target velocimetry. These include flash and arc lamps, light from detonations, pulsed lasers, chirped frequency lasers, and lasers operating simultaneously in several wavelengths. The technique is demonstrated with white light from an incandescent source to measure a target moving at 16 m/s. 41 figs.

  7. The Revival of White Holes as Small Bangs

    E-Print Network [OSTI]

    Alon Retter; Shlomo Heller

    2011-07-17

    Black holes are extremely dense and compact objects from which light cannot escape. There is an overall consensus that black holes exist and many astronomical objects are identified with black holes. White holes were understood as the exact time reversal of black holes, therefore they should continuously throw away material. It is accepted, however, that a persistent ejection of mass leads to gravitational pressure, the formation of a black hole and thus to the "death of while holes". So far, no astronomical source has been successfully tagged a white hole. The only known white hole is the Big Bang which was instantaneous rather than continuous or long-lasting. We thus suggest that the emergence of a white hole, which we name a 'Small Bang', is spontaneous - all the matter is ejected at a single pulse. Unlike black holes, white holes cannot be continuously observed rather their effect can only be detected around the event itself. Gamma ray bursts are the most energetic explosions in the universe. Long gamma-ray bursts were connected with supernova eruptions. There is a new group of gamma-ray bursts, which are relatively close to Earth, but surprisingly lack any supernova emission. We propose identifying these bursts with white holes. White holes seem like the best explanation of gamma-ray bursts that appear in voids. We also predict the detection of rare gigantic gamma-ray bursts with energies much higher than typically observed.

  8. Fig. 1: (a) TEM image of InAs HEMT fabricated in Ref. [4]. The device region enclosed in the dotted white rectangle is included in the simulation domain. (b) Schematic view of the InAs HEMT. The channel region is composed of a 10 nm InGaAs/InAs/InGaAs Mul

    E-Print Network [OSTI]

    del Alamo, Jesús A.

    in the dotted white rectangle is included in the simulation domain. (b) Schematic view of the InAs HEMT. The channel region is composed of a 10 nm InGaAs/InAs/InGaAs Multi-Quantum-Well grown on a thick In0.52Al0.48As layer lattice-matched to the InP substrate. In0.52Al0.48As layer below the gate contact acts

  9. White-Box Security Notions for Symmetric Encryption Schemes

    E-Print Network [OSTI]

    International Association for Cryptologic Research (IACR)

    in the last decade. Several white-box implementations of standard block-ciphers (DES, AES) have been proposed of a cryptosystem, cryptographers consider attack sce- narios where an adversary is only given a black-box access

  10. Is the Universe a White-Hole?

    E-Print Network [OSTI]

    Marcelo Samuel Berman

    2008-08-06

    Pathria(1972) has shown, for a pressureless closed Universe, that it is inside a black (or white) hole. We show now, that the Universe with a cosmic pressure obeying Einstein's field equations, can be inside a white-hole. In the closed case, a positive cosmological constant does the job; for the flat and open cases, the condition we find is not verified for the very early Universe, but with the growth of the scale-factor, the condition will be certainly fulfilled for a positive cosmological constant, after some time. We associate the absolute temperature of the Universe, with the temperature of the corresponding white-hole.

  11. BLACK HISTORY MONTH

    Broader source: Energy.gov [DOE]

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

  12. White sponge nevus

    E-Print Network [OSTI]

    Dadlani, Chicky; Mengden, Stephanie; Kerr, A Ross

    2008-01-01

    keratinization [ 16 ]. Although WSN is painless, patientsComment White sponge nevus (WSN), which was described byinstability [ 7 , 8 ]. Lesions of WSN appear as white-to-

  13. 2014 ended with the media turning to College of Agriculture and Life Sciences experts on headline-making stories such as New York banning fracking; the California drought; and holiday favorites, including predictions for a white

    E-Print Network [OSTI]

    Angenent, Lars T.

    -making stories such as New York banning fracking; the California drought; and holiday favorites, including kind to appear in the state. Christian Science Monitor:"New York State MovesTo Ban Fracking" 12 fracturing,or fracking. The Hill:"Winning theWar on Fossil Fuels" 12.09.2014 Charles Greene

  14. Gendered Racial Socialization in Black Families: Mothers' Beliefs, Approaches, and Advocacy

    E-Print Network [OSTI]

    Holman, Alea Rhys

    2012-01-01

    How Black students cope with racism on White campuses. Thechildren learn race and racism. Lanham: Rowman & LittlefieldS. (2008). Institutional racism: A primer on theory and

  15. The Color of Self-Love: Exposing Racism in Black Female Masturbation Research

    E-Print Network [OSTI]

    Frank, Elena

    2010-01-01

    Americans, Gender, and the New Racism. New York: Routledge,of Self-Love: Exposing Racism in Black Female Masturbationsexual deviance and construct racism and sexism. BLACK/WHITE

  16. You Cannot Press Out the Black Hole

    E-Print Network [OSTI]

    Daisuke Ida; Takahiro Okamoto

    2012-01-03

    It is shown that a ball-shaped black hole region homeomorphic with D**n cannot be pressed out, along whichever axis penetrating the black hole region, into a black ring with a doughnut-shaped black hole region homeomorphic with S**1 x D**(n-1). A more general prohibition law for the change of the topology of black holes, including a version of no-bifurcation theorems for black holes, is given.

  17. In what sense a neutron star-black hole binary is the holy grail for testing gravity?

    E-Print Network [OSTI]

    Manjari Bagchi; Diego F. Torres

    2014-07-29

    Pulsars in binary systems have been very successful to test the validity of general relativity in the strong field regime. So far, such binaries include neutron star-white dwarf (NS-WD) and neutron star-neutron star (NS-NS) systems. It is commonly believed that a neutron star-black hole (NS-BH) binary will be much superior for this purpose. But in what sense is this true? Does it apply to all possible deviations?

  18. In what sense a neutron star-black hole binary is the holy grail for testing gravity?

    E-Print Network [OSTI]

    Bagchi, Manjari

    2014-01-01

    Pulsars in binary systems have been very successful to test the validity of general relativity in the strong field regime. So far, such binaries include neutron star-white dwarf (NS-WD) and neutron star-neutron star (NS-NS) systems. It is commonly believed that a neutron star-black hole (NS-BH) binary will be much superior for this purpose. But in what sense is this true? Does it apply to all possible deviations?

  19. Book Review: Fade to Black and White: Interracial Images in Popular Culture, by Erica Chito Childs. Lanham, MD: Rowman and Littlefiled, 2009, 250 pages, $75.00 Cloth, $27.95 Paper. ISBN: 9780742560802.

    E-Print Network [OSTI]

    Henricks, Kasey

    2010-01-01

    ; GHWDLO#3;EHORZ#15;#3;EXW#3;¿UVW#3;D#3;EULHI#3;VXPPDU\\#3;RI#3;WKH#3;ERRN#3;LV#3;SURYLGHG#17; 'UDZLQJ#3;IURP#3;DQ#3;HFOHFWLF#3;EOHQG#3;RI#3;WKHRU\\#3;LQFOXGLQJ#3;V\\PEROLF#3; interactionism, intersectionality, and critical race theory, &KLOGV#3... and White presents a theoretical argument that is highly VRSKLVWLFDWHG#3; DQG#3; IXOO\\#3; GHYHORSHG#15;#3; LW#3; KDV#3; VRPH#3;PHWKRGRORJLFDO#3; SUREOHPV#3;WKDW#3;GHWUDFW#3;IURP#3;WKH#3;ERRN¶V#3;RYHUDOO#3;FRQWULEXWLRQ#3;WR#3;WKH#3; literature...

  20. Unusual Migration by a White-Tailed Deer Fawn in South Dakota

    E-Print Network [OSTI]

    migration by a flVe-day-old white- tailed deer (Odocoileus virginianus dacotensis) fawn in the central Black controlled (Ozoga and Verme 1986). Hawkins and Klimstra (1970) suggested that movements of adult does were purpose was to report an unusual migration pattern by an adult female white- #12;94 The Prairie Naturalist

  1. Electronic Monitoring White Papers

    E-Print Network [OSTI]

    Electronic Monitoring White Papers February 15, 2013 Source: NOAA Fisheries Office of Policy & Electronic Monitoring Working Group U.S. Department of Commerce National Oceanic & Atmospheric Administration.holliday@noaa.gov #12;B-1 Appendix B - Electronic Monitoring White Paper Existing Technologies National Oceanic

  2. Merging White Dwarfs and Thermonuclear Supernovae

    E-Print Network [OSTI]

    van Kerkwijk, Marten H

    2012-01-01

    Thermonuclear supernovae result when interaction with a companion reignites nuclear fusion in a carbon-oxygen white dwarf, causing a thermonuclear runaway, a catastrophic gain in pressure, and the disintegration of the whole white dwarf. It is usually thought that fusion is reignited in near-pycnonuclear conditions when the white dwarf approaches the Chandrasekhar mass. I briefly describe two long-standing problems faced by this scenario, and our suggestion that these supernovae instead result from mergers of carbon-oxygen white dwarfs, including those that produce sub-Chandrasekhar mass remnants. I then turn to possible observational tests, in particular those that test the absence or presence of electron captures during the burning.

  3. How tall is the White Ash tree? White Ash tree

    E-Print Network [OSTI]

    Ashline, George

    How tall is the White Ash tree? White Ash tree Sapling Activity Tree location Try this: · Measure the length of the White Ash's shadow on a nice sunny day. Place the end of your measuring tape at the base of the shadow. Record the length on your paper. · Next measure your shadow. Stand next to the White Ash and have

  4. Black hole microstates in AdS

    E-Print Network [OSTI]

    Shaghoulian, Edgar

    2015-01-01

    We extend a recently derived higher-dimensional Cardy formula to include angular momenta, which we use to obtain the Bekensten-Hawking entropy of AdS black branes, compactified rotating branes, and large Schwarzschild/Kerr black holes. This is the natural generalization of Strominger's microscopic derivation of the BTZ black hole entropy to higher dimensions. We propose an extension to include $U(1)$ charge, which agrees with the Bekenstein-Hawking entropy of large Reissner-Nordstrom/Kerr-Newman black holes at high temperature. We extend the results to arbitrary hyperscaling violation exponent (this captures the case of black D$p$-branes as a subclass) and reproduce logarithmic corrections.

  5. PAINT IT BLACK--A COMBINATORIAL YAWP ARTHUR T. BENJAMIN, JENNIFER J. QUINN, JAMES A. SELLERS, AND MARK A.

    E-Print Network [OSTI]

    Sellers, James A.

    PAINT IT BLACK--A COMBINATORIAL YAWP ARTHUR T. BENJAMIN, JENNIFER J. QUINN, JAMES A. SELLERS to select subsets, to paint elements black, blue, or white, and to count, we will work through a novel proof of the pairs to paint black in n r ways. Of the remaining 2n - 2r elements that have not yet been painted

  6. Spirituality and Race in Career Decision Making: Perspectives of Blacks Who Recently Graduated from Undergraduate Programs 

    E-Print Network [OSTI]

    Turner-Driver, Tonya

    2014-06-30

    The purpose of this study was to examine how racial and spiritual identities influenced career decision making among a select group of Blacks who recently graduated from undergraduate programs at a Predominately White ...

  7. Cooling Models for Old White Dwarfs

    E-Print Network [OSTI]

    Brad M. S. Hansen

    1999-03-02

    We present new white dwarf cooling models which incorporate an accurate outer boundary condition based on new opacity and detailed radiative transfer calculations. We find that helium atmosphere dwarfs cool considerably faster than has previously been claimed, while old hydrogen atmosphere dwarfs will deviate significantly from black body appearance. We use our new models to derive age limits for the Galactic disk. We find that the Liebert, Dahn & Monet (1988) luminosity function yields an age of only 6 Gyr if it is complete to stated limits. However, age estimates of individual dwarfs and the luminosity function of Oswalt et al (1995) are both consistent with disk ages as large as \\sim 11 Gyr. We have also used our models to place constraints on white dwarf dark matter in Galactic halos. We find that previous attempts using inadequate cooling models were too severe and that direct detection limits allow a halo that is 11 Gyr old. If the halo is composed solely of helium atmosphere dwarfs, the lower age limit is only 7.5 Gyr. We also demonstrate the importance of studying the cooling sequences of white dwarfs in Globular clusters.

  8. ASTRO-H White Paper - White Dwarf

    E-Print Network [OSTI]

    Mukai, K; Harayama, A; Hayashi, T; Ishida, M; Long, K S; Terada, Y; Tsujimoto, M

    2014-01-01

    Interacting binaries in which a white dwarf accretes material from a companion --- cataclysmic variables (CVs) in which the mass loss is via Roche-lobe overflow, and symbiotic stars in which the white dwarf captures the wind of a late type giant --- are relatively commonplace. They display a wide range of behaviors in the optical, X-rays, and other wavelengths, which still often baffles observers and theorists alike. They are likely to be a significant contributor to the Galactic ridge X-ray emission, and the possibility that some CVs or symbiotic stars may be the progenitors of some of the Type Ia supernovae deserves serious consideration. Furthermore, these binaries serve as excellent laboratories in which to study physics of X-ray emission from high density plasma, accretion physics, reflection, and particle acceleration. ASTRO-H is well-matched to the study of X-ray emission from many of these objects. In particular, the excellent spectral resolution of the SXS will enable dynamical studies of the X-ray e...

  9. Axions and White Dwarfs

    E-Print Network [OSTI]

    J. Isern; S. Catalan; E. Garcia-Berro; M. Salaris; S. Torres

    2010-10-26

    White dwarfs are almost completely degenerate objects that cannot obtain energy from the thermonuclear sources and their evolution is just a gravothermal process of cooling. The simplicity of these objects, the fact that the physical inputs necessary to understand them are well identified, although not always well understood, and the impressive observational background about white dwarfs make them the most well studied Galactic population. These characteristics allow to use them as laboratories to test new ideas of physics. In this contribution we discuss the robustness of the method and its application to the axion case.

  10. Thermal Gravitational Waves from Primordial Black Holes

    E-Print Network [OSTI]

    C. Sivaram; Kenath Arun

    2010-05-19

    Thermal gravitational waves can be generated in various sources such as, in the cores of stars, white dwarfs and neutron stars due to the fermion collisions in the dense degenerate Fermi gas. Such high frequency thermal gravitational waves can also be produced during the collisions in a gamma ray burst or during the final stages of the evaporation of primordial black holes. Here we estimate the thermal gravitational waves from primordial black holes and estimate the integrated energy of the gravitational wave emission over the entire volume of the universe and over Hubble time. We also estimate the gravitational wave flux from gamma ray bursts and jets.

  11. White House Tribal Nations Conference

    Broader source: Energy.gov [DOE]

    The White House will host the seventh annual Tribal Nations Conference to allow tribal leaders to engage with the President, cabinet officials, and the White House Council on Native America Affairs about key issues facing tribes.

  12. Black Pine Circle Project

    SciTech Connect (OSTI)

    Mytko, Christine

    2014-03-31

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

  13. Black Pine Circle Project

    ScienceCinema (OSTI)

    Mytko, Christine

    2014-09-15

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

  14. White House Tribal Youth Gathering

    Broader source: Energy.gov [DOE]

    The White House will host the first-ever White House Tribal Youth Gathering to provide American Indian and Alaska Native youth from across the country the opportunity to interact directly with senior Administration officials and the White House Council on Native American Affairs. Registration is due May 8, 2015.

  15. Technical background information for the environmental and safety report, Volume 4: White Oak Lake and Dam

    SciTech Connect (OSTI)

    Oakes, T.W.; Kelly, B.A.; Ohnesorge, W.F.; Eldridge, J.S.; Bird, J.C.; Shank, K.E.; Tsakeres, F.S.

    1982-03-01

    This report has been prepared to provide background information on White Oak Lake for the Oak Ridge National Laboratory Environmental and Safety Report. The paper presents the history of White Oak Dam and Lake and describes the hydrological conditions of the White Oak Creek watershed. Past and present sediment and water data are included; pathway analyses are described in detail.

  16. Dynamics of galaxy cores and supermassive black holes

    E-Print Network [OSTI]

    David Merritt

    2006-05-02

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

  17. 2013 White Book, Pacific Northwest Loads and Resources Study (summary)

    SciTech Connect (OSTI)

    2013-10-01

    The 2013 Pacific Northwest Loads and Resources Study (2013 White Book) is BPA's latest projection of the Pacific Northwest regional retail loads, contract obligations, contract purchases, and resource capabilities. The 2013 White Book is a snapshot of conditions as of October 1, 2013, documenting the loads and resources for the Federal system and region for the 10-year study period OY 2014 through 2023. The White Book contains projections of regional and Federal system load and resource capabilities, along with relevant definitions and explanations. The White Book also contains information obtained from formalized resource planning reports and data submittals including those from individual utilities, the Northwest Power and Conservation Council (Council), and the Pacific Northwest Utilities Conference Committee (PNUCC). Starting with the 2012 White Book, BPA changed the annual production schedule for future White Books. BPA is scheduled to publish a complete White Book, which includes a Federal System Needs Assessment analysis, every other year (even years). In the odd-numbered years, BPA will publish a biennial summary update (Supplement) that only contains major changes to the Federal System and Regional System analyses that have occurred since the last White Book. http://www.bpa.gov/power/pgp/whitebook/2013/index.shtml.

  18. Vertebral Bomb Radiocarbon Suggests Extreme Longevity in White Sharks

    E-Print Network [OSTI]

    Hamady, Li Ling

    Conservation and management efforts for white sharks (Carcharodon carcharias) remain hampered by a lack of basic demographic information including age and growth rates. Sharks are typically aged by counting growth bands ...

  19. Strengthening Sustainable Manufacturing in The White House, Environmental Protection Agency

    E-Print Network [OSTI]

    manufacturing. Topics of discussion will include sustainable manufacturing, lean manufacturing, workforce issuesStrengthening Sustainable Manufacturing in Indiana The White House, Environmental Protection Agency to participate in an event with Matt Bogoshian, to discuss Sustainable Manufacturing, which was featured

  20. DUSEL Theory White Paper

    E-Print Network [OSTI]

    S. Raby; T. Walker; K. S. Babu; H. Baer; A. B. Balantekin; V. Barger; Z. Berezhiani; A. de Gouvea; R. Dermisek; A. Dolgov; P. Fileviez Perez; G. Gabadadze; A. Gal; P. Gondolo; W. Haxton; Y. Kamyshkov; B. Kayser; E. Kearns; B. Kopeliovich; K. Lande; D. Marfatia; R. N. Mohapatra; P. Nath; Y. Nomura; K. A. Olive; J. Pati; S. Profumo; R. Shrock; Z. Tavartkiladze; K. Whisnant; L. Wolfenstein

    2008-10-24

    The NSF has chosen the site for the Deep Underground Science and Engineering Laboratory (DUSEL) to be in Lead, South Dakota. In fact, the state of South Dakota has already stepped up to the plate and contributed its own funding for the proposed lab, see http://www.sanfordlaboratoryathomestake.org/index.html. The final decision by NSF for funding the Initial Suite of Experiments for DUSEL will be made early in 2009. At that time the NSF Science Board must make a decision. Of order 200 experimentalists have already expressed an interest in performing experiments at DUSEL. In order to assess the interest of the theoretical community, the Center for Cosmology and Astro-Particle Physics (CCAPP) at The Ohio State University (OSU) organized a 3-day DUSEL Theory Workshop in Columbus, Ohio from April 4 - 6, 2008. The workshop focused on the scientific case for six proposed experiments for DUSEL: long baseline neutrino oscillations, proton decay, dark matter, astrophysical neutrinos, neutrinoless double beta decay and N-Nbar oscillations. The outcome of this workshop is the DUSEL Theory White paper addressing the scientific case at a level which may be useful in the decision making process for policy makers at the NSF and in the U.S. Congress. In order to assess the physics interest in the DUSEL project we have posted the DUSEL Theory White paper on the following CCAPP link http://ccapp.osu.edu/whitepaper.html . Please read the white paper and, if you are interested, use the link to show your support by co-signing the white paper.

  1. The Status and future of ground-based TeV gamma-ray astronomy. A White Paper prepared for the Division of Astrophysics of the American Physical Society

    E-Print Network [OSTI]

    Buckley, J; Dingus, B; Falcone, A; Kaaret, Philip; Krawzcynski, H; Pohl, M; Vasilev, V; Williams, D A

    2008-01-01

    In recent years, ground-based TeV gamma-ray observatories have made spectacular discoveries including imaging spectroscopy observations of galactic sources of different classes, and the discovery of rapid gamma-ray flares from radio galaxies and active galactic nuclei containing supermassive black holes. These discoveries, and the fact that gamma-ray astronomy has the potential to map the radiation from dark matter annihilation in our Galaxy and in extragalactic systems, have attracted the attention of the wider scientific community. The Division of Astrophysics of the American Physical Society requested the preparation of a white paper on the status and future of ground-based gamma-ray astronomy to define the science goals of a future observatory, to determine the performance specifications, to identify the areas of necessary technology development, and to lay out a clear path for proceeding beyond the near term. The white paper was written with broad community input, including discussions on several dedicat...

  2. Differential white cell count by centrifugal microfluidics.

    SciTech Connect (OSTI)

    Sommer, Gregory Jon; Tentori, Augusto M.; Schaff, Ulrich Y.

    2010-07-01

    We present a method for counting white blood cells that is uniquely compatible with centrifugation based microfluidics. Blood is deposited on top of one or more layers of density media within a microfluidic disk. Spinning the disk causes the cell populations within whole blood to settle through the media, reaching an equilibrium based on the density of each cell type. Separation and fluorescence measurement of cell types stained with a DNA dye is demonstrated using this technique. The integrated signal from bands of fluorescent microspheres is shown to be proportional to their initial concentration in suspension. Among the current generation of medical diagnostics are devices based on the principle of centrifuging a CD sized disk functionalized with microfluidics. These portable 'lab on a disk' devices are capable of conducting multiple assays directly from a blood sample, embodied by platforms developed by Gyros, Samsung, and Abaxis. [1,2] However, no centrifugal platform to date includes a differential white blood cell count, which is an important metric complimentary to diagnostic assays. Measuring the differential white blood cell count (the relative fraction of granulocytes, lymphocytes, and monocytes) is a standard medical diagnostic technique useful for identifying sepsis, leukemia, AIDS, radiation exposure, and a host of other conditions that affect the immune system. Several methods exist for measuring the relative white blood cell count including flow cytometry, electrical impedance, and visual identification from a stained drop of blood under a microscope. However, none of these methods is easily incorporated into a centrifugal microfluidic diagnostic platform.

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

    E-Print Network [OSTI]

    Slatton, Brittany C.

    2012-02-14

    the bounds of hegemonic femininity, beauty, sexuality, and womanhood. Using the theoretical concept deep frame, which is the "conceptual infrastructure of the mind" (Lakoff 2006a:12) and representative of one's commonsense world view, I argue that the ways...

  4. Doing development: Going beyond black and white understandings

    E-Print Network [OSTI]

    Narasayya, Vivek

    #12;WHAT CHARACTERISES POVERTY? Discussion on: Collins, D., Morduch, J., Rutherford, S. and O. Ruthven · Focus on savings / money management · Importance of marriages and festivals · Borrowing and savings · Shortsightedness versus long term (financial) goals · Having electricity · Borrowing and saving from multiple

  5. The compressibility of cubic white, orthorhombic black and rhombohedral

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail. (Conference)FeedbackProperties ofTheatmosphere (Journaltransmission lines

  6. The compressibility of cubic white, orthorhombic black and rhombohedral

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail. (Conference)FeedbackProperties ofTheatmosphere (Journaltransmission linesblack

  7. OSR 25-82 WSRC Formal Letterhead (Black and White)

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformationJesseworkSURVEY UNIVERSEHow ORISE isParisTeam Office of RiverSite's Dennis Yates

  8. Mesolensing Explorations of Nearby Masses: From Planets to Black Holes

    E-Print Network [OSTI]

    R. Di Stefano

    2007-12-20

    Nearby masses can have a high probability of lensing stars in a distant background field. High-probability lensing, or mesolensing, can therefore be used to dramatically increase our knowledge of dark and dim objects in the solar neighborhood, where it can discover and study members of the local dark population (free-floating planets, low-mass dwarfs, white dwarfs, neutron stars, and stellar mass black holes). We can measure the mass and transverse velocity of those objects discovered (or already known), and determine whether or not they are in binaries with dim companions. We explore these and other applications of mesolensing, including the study of forms of matter that have been hypothesized but not discovered, such as intermediate-mass black holes, dark matter objects free-streaming through the Galactic disk, and planets in the outermost regions of the solar system. In each case we discuss the feasibility of deriving results based on present-day monitoring systems, and also consider the vistas that will open with the advent of all-sky monitoring in the era of the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS), and the Large Synoptic Survey Telescope (LSST).

  9. Del Black

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformation Current HAB Packet HanfordDOEDanielDe novo Design ofDefects LeadDel Black Del

  10. Pump apparatus including deconsolidator

    DOE Patents [OSTI]

    Sonwane, Chandrashekhar; Saunders, Timothy; Fitzsimmons, Mark Andrew

    2014-10-07

    A pump apparatus includes a particulate pump that defines a passage that extends from an inlet to an outlet. A duct is in flow communication with the outlet. The duct includes a deconsolidator configured to fragment particle agglomerates received from the passage.

  11. Patterns of avian diversification in Borneo: The case of the endemic Mountain Black-eye (Chlorocharis emiliae)

    E-Print Network [OSTI]

    Gawin, Dency F.; Rahman, Mustafa Abdul; Ramji, Mohamad Fizl Sidq; Smith, Brian Tilston; Lim, Haw Chuan; Moyle, Robert G.; Sheldon, Frederick H.

    2014-01-01

    The Mountain Black-eye (Chlorocharis emiliae) is an endemic white-eye (Zosteropidae) of Borneo with a unique “sky island” distribution. We compared mitochondrial ND2, ND3, Cytb, and control region DNA sequences (2,194 ...

  12. Relationship of Black Holes to Bulges

    E-Print Network [OSTI]

    David Merritt; Laura Ferrarese

    2001-07-08

    Supermassive black holes appear to be uniquely associated with galactic bulges. The mean ratio of black hole mass to bulge mass was until recently very uncertain, with ground based, stellar kinematical data giving a value roughly an order of magnitude larger than other techniques. The discrepancy was resolved with the discovery of the M-sigma relation, which simultaneously established a tight corrrelation between black hole mass and bulge velocity dispersion, and confirmed that the stellar kinematical mass estimates were systematically too large due to failure to resolve the black hole's sphere of influence. There is now excellent agreement between the various techniques for estimating the mean black hole mass, including dynamical mass estimation in quiescent galaxies; reverberation mapping in active galaxies and quasars; and computation of the mean density of compact objects based on integrated quasar light. Implications of the M-sigma relation for the formation of black holes are discussed.

  13. Brendan M. White

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room News PublicationsAudits &Bradbury Science Museum - ScienceBrendan M. White About ESnet Our

  14. Sandia Energy - Jonathan White

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust, High-Throughput Analysis ofSample SULIColinEnergyComputationalJBEI(Jon) Berg HomeWhite

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

    E-Print Network [OSTI]

    to the chondritic uniform reservoir (CHUR; black line) and the depleted mantle (purple line). The parameters of CHUR by calcite. Fig. 5. Pyritized fracture Fig. 6. Massive black shale Fig. 7. Graptolite in black shale Fig. 8 shale, - Measure the concentrations of major, minor and trace elements including organic carbon

  16. Holographic Black Hole Chemistry

    E-Print Network [OSTI]

    Andreas Karch; Brandon Robinson

    2015-11-02

    Thermodynamic quantities associated with black holes in Anti-de Sitter space obey an interesting identity when the cosmological constant is included as one of the dynamical variables, the generalized Smarr relation. We show that this relation can easily be understood from the point of view of the dual holographic field theory. It amounts to the simple statement that the extensive thermodynamic quantities of a large $N$ gauge theory only depend on the number of colors, $N$, via an overall factor of $N^2$.

  17. Noncommutative Black-Body Radiation: Implications On Cosmic Microwave Background

    E-Print Network [OSTI]

    Amir H. Fatollahi; Maryam Hajirahimi

    2006-07-12

    Including loop corrections, black-body radiation in noncommutative space is anisotropic. A direct implication of possible space noncommutativity on the Cosmic Microwave Background map is argued.

  18. Nondestructive Evaluation and Monitoring Projects NASA White...

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

    Nondestructive Evaluation and Monitoring Projects NASA White Sands Test Facility (WSTF) Nondestructive Evaluation and Monitoring Projects NASA White Sands Test Facility (WSTF)...

  19. Greening of the White House: Six year report

    SciTech Connect (OSTI)

    None

    1999-11-01

    The White House, which recently celebrated its 200th birthday, has a long tradition of demonstrating technological innovation. In keeping with that tradition, President Clinton announced the Greening of the White House Initiative on Earth Day 1993. The initiative improves the energy and environmental performance of the White House complex by identifying opportunities to reduce waste, lower energy use, and make an appropriate use of renewable resources, all while improving indoor air quality and building comfort. This report on President Clinton's legacy of greening at the White House summarizes progress made to date and gives an overview of new opportunities identified during the past year. It also includes an environmental history of the White House and a short tour of the buildings that make up the White House complex. Over the past five years, this initiative has involved hundreds of dedicated people from both within and outside government. A description of how they worked together to develop and implement the Greening Plan is also included in this report.

  20. Fourier Analysis of the BTZ Black Hole

    E-Print Network [OSTI]

    Ian M. Tolfree

    2009-11-11

    In this paper we extend our previous work regarding the role of the Fourier transformation in bulk to boundary mappings to include the BTZ black hole. We follow standard procedures for modifying Fourier Transformations to accommodate quotient spaces and arrive at a bulk to boundary mapping in a black hole background. We show that this mapping is consistent with known results and lends a new insight into the AdS/CFT duality. We find that the micro-states corresponding to the entropy of a bulk scalar field are the Fourier coefficients on the boundary, which transform under the principal series representation of $SL(2,R)$. Building upon this we present a toy model to analyze the implications of this for the origin of black hole entropy. We find that the black hole micro-states live on the boundary and correspond to the possible emission modes of the black hole

  1. How fast can a black hole rotate?

    E-Print Network [OSTI]

    Herdeiro, Carlos A R

    2015-01-01

    Kerr black holes have their angular momentum, $J$, bounded by their mass, $M$: $Jc\\leqslant GM^2$. There are, however, known black hole solutions violating this Kerr bound. We propose a very simple universal bound on the rotation, rather than on the angular momentum, of four-dimensional, stationary and axisymmetric, asymptotically flat black holes, given in terms of an appropriately defined horizon linear velocity, $v_H$. The $v_H$ bound is simply that $v_H$ cannot exceed the velocity of light. We verify the $v_H$ bound for known black hole solutions, including some that violate the Kerr bound, and conjecture that only extremal Kerr black holes saturate the $v_H$ bound.

  2. Supermassive Black Holes

    E-Print Network [OSTI]

    Laura Ferrarese; David Merritt

    2002-06-13

    After a brief historical introduction, we summarize current efforts and accomplishments in the study of supermassive black holes.

  3. The Status and future of ground-based TeV gamma-ray astronomy. A White Paper prepared for the Division of Astrophysics of the American Physical Society

    E-Print Network [OSTI]

    J. Buckley; K. Byrum; B. Dingus; A. Falcone; P. Kaaret; H. Krawzcynski; M. Pohl; V. Vassiliev; D. A. Williams

    2008-10-02

    In recent years, ground-based TeV gamma-ray observatories have made spectacular discoveries including imaging spectroscopy observations of galactic sources of different classes, and the discovery of rapid gamma-ray flares from radio galaxies and active galactic nuclei containing supermassive black holes. These discoveries, and the fact that gamma-ray astronomy has the potential to map the radiation from dark matter annihilation in our Galaxy and in extragalactic systems, have attracted the attention of the wider scientific community. The Division of Astrophysics of the American Physical Society requested the preparation of a white paper on the status and future of ground-based gamma-ray astronomy to define the science goals of a future observatory, to determine the performance specifications, to identify the areas of necessary technology development, and to lay out a clear path for proceeding beyond the near term. The white paper was written with broad community input, including discussions on several dedicated open meetings, and a number of APS or other conferences. It contains an executive summary, detailed reports from the science working groups, and appendices with supplementary material including the full author lists for the different sections of the white paper and a glossary.

  4. Polymer OLED White Light Development Program

    SciTech Connect (OSTI)

    Homer Antoniadis; Vi-En Choong; Stelios Choulis; Brian Cumpston; Rahul Gupta; Mathew Mathai; Michael Moyer; Franky So

    2005-12-19

    OSRAM Opto Semiconductors (OSRAM) successfully completed development, fabrication and characterization of the large area, polymer based white light OLED prototype at their OLED Research and Development (R&D) facility in San Jose, CA. The program, funded by the Department of Energy (DOE), consisted of three key objectives: (1) Develop new polymer materials and device architectures--in order to improve the performance of organic light emitters. (2) Develop processing techniques--in order to demonstrate and enable the manufacturing of large area, white light and color tunable, solid state light sources. (3) Develop new electronics and driving schemes for organic light sources, including color-tunable light sources. The key performance goals are listed. A world record efficiency of 25 lm/W was established for the solution processed white organic device from the significant improvements made during the project. However, the challenges to transfer this technology from an R&D level to a large tile format such as, the robustness of the device and the coating uniformity of large area panels, remain. In this regard, the purity and the blend nature of the materials are two factors that need to be addressed in future work. During the first year, OSRAM's Materials and Device group (M&D) worked closely with the major polymer material suppliers to develop the polymer emissive technology. M&D was successful in demonstrating a 7-8 lm/W white light source which was based on fluorescent materials. However, it became apparent that the major gains in efficiency could only be made if phosphorescent materials were utilized. Thus, in order to improve the performance of the resulting devices, the focus of the project shifted towards development of solution-processable phosphorescent light emitting diodes (PHOLEDs) and device architectures. The result is a higher efficiency than the outlined project milestone.

  5. Classical and Quantum Properties of Liouville Black Holes

    E-Print Network [OSTI]

    R. B. Mann

    1994-04-25

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

  6. Black Pine Engineering

    Office of Energy Efficiency and Renewable Energy (EERE)

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

  7. Magnetized static black Saturn

    E-Print Network [OSTI]

    Stoytcho S. Yazadjiev

    2008-02-06

    We construct a new static solution to the 5D Einstein-Maxwell equations describing a static black hole surrounded by a non-rotating dipole black ring. The configuration is kept in equilibrium by an external magnetic field interacting with the dipole charge of the black ring. The properties of the black Saturn-like configuration are studied and the basic physical quantities are calculated. The solution demonstrates 2-fold continuous non-uniqueness of the 5D magnetized static neutral black objects for fixed total mass and Melvin background.

  8. Charged Cylindrical Black Holes in Conformal Gravity

    E-Print Network [OSTI]

    Jackson Levi Said; Joseph Sultana; Kristian Zarb Adami

    2013-01-04

    Considering cylindrical topology we present the static solution for a charged black hole in conformal gravity. We show that unlike the general relativistic case there are two different solutions, both including a factor that when set to zero recovers the familiar static charged black string solution in Einstein's theory. This factor gives rise to a linear term in the potential that also features in the neutral case and may have significant ramifications for particle trajectories.

  9. New white dwarf and subdwarf stars in the Sloan Digital Sky Survey Data Release 12

    E-Print Network [OSTI]

    Kepler, S O; Koester, Detlev; Ourique, Gustavo; Romero, Alejandra Daniela; Reindl, Nicole; Kleinman, Scot J; Eisenstein, Daniel J; Valois, A Dean M; Amaral, Larissa A

    2015-01-01

    We report the discovery of 6576 new spectroscopically confirmed white dwarf and subdwarf stars in the Sloan Digital Sky Survey Data Release 12. We obtain Teff, log g and mass for hydrogen atmosphere white dwarf stars (DAs) and helium atmosphere white dwarf stars (DBs), estimate the calcium/helium abundances for the white dwarf stars with metallic lines (DZs) and carbon/helium for carbon dominated spectra DQs. We found one central star of a planetary nebula, one ultra-compact helium binary (AM CVn), one oxygen line dominated white dwarf, 15 hot DO/PG1159s, 12 new cataclysmic variables, 36 magnetic white dwarf stars, 54 DQs, 115 helium dominated white dwarfs, 148 white dwarf+main sequence star binaries, 236 metal polluted white dwarfs, 300 continuum spectra DCs, 230 hot subdwarfs, 2936 new hydrogen dominated white dwarf stars, and 2675 cool hydrogen dominated subdwarf stars. We calculate the mass distribution of all 5883 DAs with S/N>15 in DR12, including the ones in DR7 and DR10, with an average S/N=26, correc...

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

    SciTech Connect (OSTI)

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

    1987-10-01

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

  11. Sandia Energy - White House Business Council Roundtable on Water

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

    Protected: White House Business Council Roundtable on Water Home Climate Water Security Protected: White House Business Council Roundtable on Water Previous Next Protected: White...

  12. Bicycling Black Rings

    E-Print Network [OSTI]

    Henriette Elvang; Maria J. Rodriguez

    2008-01-25

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

  13. Bicycling Black Rings

    E-Print Network [OSTI]

    Elvang, Henriette

    2008-01-01

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

  14. Topological Black Holes -- Outside Looking In

    E-Print Network [OSTI]

    R. B. Mann

    1997-09-15

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

  15. Thermovoltaic semiconductor device including a plasma filter

    DOE Patents [OSTI]

    Baldasaro, Paul F. (Clifton Park, NY)

    1999-01-01

    A thermovoltaic energy conversion device and related method for converting thermal energy into an electrical potential. An interference filter is provided on a semiconductor thermovoltaic cell to pre-filter black body radiation. The semiconductor thermovoltaic cell includes a P/N junction supported on a substrate which converts incident thermal energy below the semiconductor junction band gap into electrical potential. The semiconductor substrate is doped to provide a plasma filter which reflects back energy having a wavelength which is above the band gap and which is ineffectively filtered by the interference filter, through the P/N junction to the source of radiation thereby avoiding parasitic absorption of the unusable portion of the thermal radiation energy.

  16. Accreting Black Holes

    E-Print Network [OSTI]

    Begelman, Mitchell C

    2014-01-01

    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.

  17. Amplification induced by white noise

    E-Print Network [OSTI]

    Masamichi Ishihara

    2006-03-01

    We investigate the amplification of the field induced by white noise. In the present study, we study a stochastic equation which has two parameters, the energy $\\omega(\\vec{k})$ of a free particle and the coupling strength $D$ between the field and white noise, where the quantity $\\vec{k}$ represents the momentum of a free particle. This equation is reduced to the equation with one parameter $\\alpha(\\vec{k})$ which is defined as $\\alpha(\\vec{k}) = D (\\omega(\\vec{k}))^{-3/2}$. We obtain the expression of the exponent statistically averaged over the unit time and derive an approximate expression of it. In addition, the exponent is obtained numerically by solving the stochastic equation. We find that the amplification increases with $\\alpha(\\vec{k})$. This indicates that white noise can amplify the fields for soft modes if the mass $m$ of the field is sufficiently light and if the strength of the coupling between the field and white noise is sufficiently strong, when the energy $\\omega(\\vec{k})$ is equal to $\\sqrt{m^{2} + \\vec{k}^{2}}$. We show that the $\\alpha(\\vec{k})$ dependence of the exponent statistically averaged is qualitatively similar to that of the exponent obtained by solving the stochastic equation numerically, and that these two exponents for the small value of $\\alpha(\\vec{k})$ are quantitatively similar.

  18. Service management solutions White paper

    E-Print Network [OSTI]

    an end-to-end service perspective. · Service management platform is built on IBM Tivoli Change to help align operations with business context and enable customers to manage change. Tivoli CCMDBService management solutions White paper Netcool + Tivoli: delivering service management innovation

  19. Hyperscale Cloud Technical White Paper

    E-Print Network [OSTI]

    Chaudhuri, Surajit

    Hyperscale Cloud Technical White Paper Published: May 2015 Applies to: SQL Server 2016 CTP2, SQL in the cloud with greater scale and flexibility. Microsoft SQL Server is built for cloud integration--your organization can easily deploy SQL Server in a private cloud, hybrid cloud, or public cloud, and can use

  20. A comprehensive program to develop correlations for physical properties of kraft black liquor. Final report

    SciTech Connect (OSTI)

    Fricke, A.L.; Zaman, A.A.; Stoy, M.O.; Schmidl, G.W.; Dong, D.J.; Speck, B.

    1998-04-01

    A wide variety of experimental techniques have been used in this work, and many of these have been developed completely or improved significantly in the course of the research done during this program. Therefore, it is appropriate to describe these techniques in detail as a reference for future workers so that the techniques can be used in future work with little additional effort or so that the results reported from this program can be compared better with future results from other work. In many cases, the techniques described are for specific analytical instruments. It is recognized that these may be superseded by future developments and improvements in instrumentation if a complete description of techniques used successfully in the past on other instrumentation is available. The total pulping and liquor preparation research work performed included chip and white liquor preparation, digestion, pulp washing, liquor and wash recovery, liquor sampling, weak liquor concentration in two steps to about 45--50% solids with an intermediate soap skimming at about 140F and 27--30% solids, determination of pulp yield and Kappa number, determination of total liquor solids, and a check on the total material balance for pulping. All other research was performed either on a sample of the weak black liquor (the combined black liquor and washes from the digester) or on the skimmed liquor that had been concentrated.

  1. Inside the White House: Solar Panels

    Broader source: Energy.gov [DOE]

    Go inside the White House and learn about the installation of solar panels on the roof of the residence.

  2. Antonia White: no role for women writers 

    E-Print Network [OSTI]

    Witt, Amanda Beth

    1992-01-01

    face in coming to write, as revealed through White's autobiographical novels Frost in Nay (1933) and The lost Traveller (1950). First, I explain White's opinion that no role exists in which women can write without penalty; White believes... for their ambition. Next, I examine the roles White sets forth as open to women; none of these roles allows women to retain both intelligent expression and typical femininity' The main character, called Nanda in Frost in May and Clara in The l, ost Traveller...

  3. Development of Advanced Manufacturing Methods for Warm White LEDs for General Lighting

    SciTech Connect (OSTI)

    Deshpande, Anirudha; Kolodin, Boris; Jacob, Cherian; Chowdhury, Ashfaqul; Kuenzler, Glenn; Sater, Karen; Aesram, Danny; Glaettli, Steven; Gallagher, Brian; Langer, Paul; Setlur, Anant; Beers, Bill

    2012-03-31

    GE Lighting Solutions will develop precise and efficient manufacturing techniques for the “remote phosphor” platform of warm-white LED products. In volume, this will be demonstrated to drive significant materials, labor and capital productivity to achieve a maximum possible 53% reduction in overall cost. In addition, the typical total color variation for these white LEDs in production will be well within the ANSI bins and as low as a 4-step MacAdam ellipse centered on the black body curve. Achievement of both of these objectives will be demonstrated while meeting a performance target of > 75 lm/W for a warm-white LED and a reliability target of <30% lumen drop / <2-step MacAdam ellipse shift, estimated over 50,000 hrs.

  4. Let's makeleaf people! White Ash tree

    E-Print Network [OSTI]

    Ashline, George

    Let's makeleaf people! White Ash tree Seedling Activity Tree location Let's start by exploring the leaf of the White Ash tree! Can you describe the leaf? Does it have smooth-edges or rough-edges? What of anything? Try this... Let's create leaf people from the shape of the White Ash leaves. The shape

  5. Table of Contents White Coat 1

    E-Print Network [OSTI]

    Chapman, Michael S.

    Table of Contents White Coat 1 Staff Profiles 2/3/4 Recent Photos 5 New SOD'ers 6 State of School 7 on page six) Dental Bites October 2014 Class of 2017 Receives White Coats The Class of 2017 was recognized of patients. Seventy-five second-year dental students received their personalized white lab coats in a formal

  6. McGraw Hill encyclopedia of science and technology. An international reference work in fifteen volumes including an index

    SciTech Connect (OSTI)

    Not Available

    1982-01-01

    This extensively revised and updated 5th Edition features contributions by 3000 distinguished experts - including 16 Nobel Prize winners - working with an international advisory board and 60 consulting editors. Thorough coverage is devoted to 75 separate disciplines in science and technology, from acoustics and biochemistry through fluid mechanics and geophysics to thermodynamics and vertebrate zoology. Detailed entries examine not only the physical and natural sciences, but also all engineering disciplines, discussing both the basic and the most recent theories, concepts, terminology, discoveries, materials, methods, and techniques. All of the new developments and technical advances that have occurred during the last five years - in each of the 75 disciplines - have been added to the encyclopedia and are explored in depth. Completely new material deals with such timely and newsworthy subjects as genetic engineering, artificial intelligence, nuclear medicine, desertification, psycholinguistics, industrial robots, and immunoassay. Also covered in extensive entries are such current topics as video disk recording, metallic glasses, acoustic levitation, magnetic bubble memory, gluons, and computerized tomography. The encyclopedia includes more than 15,000 photographs, drawings, maps, charts, and diagrams, shown in full-color, two-color, or black-and-white reproductions.

  7. White House Conference on Global Climate Change

    SciTech Connect (OSTI)

    Not Available

    1993-11-01

    President Clinton has directed the White House office on Environmental Policy to coordinate an interagency process to develop a plan to fulfill the commitment he made in his Earth Day address on April 21, 1993. This plan will become the cornerstone of the Climate Change Plan that will be completed shortly after the Rio Accord enters into force. The Office on Environmental Policy established the Interagency Climate Change Mitigation Group to draw on the expertise of federal agencies including the National Economic Council; the Council of Economic Advisors; the Office of Science and Technology Policy; the Office of Management and Budget; the National Security Council; the Domestic Policy Council; the Environmental Protection Agency; and the Departments of Energy, Transportation, Agriculture, Interior, Treasury, Commerce, and State. Working groups have been established to examine six key policy areas: energy demand, energy supply, joint implementation, methane and other gases, sinks, and transportation. The purpose of the White House Conference on Global Climate Change was to ``tap the real-world experiences`` of diverse participants and seek ideas and information for meeting the President`s goals. During the opening session, senior administration officials defined the challenge ahead and encouraged open and frank conversation about the best possible ways to meet it.

  8. Rotating Hairy Black Holes

    E-Print Network [OSTI]

    B. Kleihaus; J. Kunz

    2000-12-20

    We construct stationary black holes in SU(2) Einstein-Yang-Mills theory, which carry angular momentum and electric charge. Possessing non-trivial non-abelian magnetic fields outside their regular event horizon, they represent non-perturbative rotating hairy black holes.

  9. "Hybrid" Black Holes

    E-Print Network [OSTI]

    Valeri P. Frolov; Andrei V. Frolov

    2014-12-30

    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.

  10. Thermodynamics of rotating black holes in conformal gravity

    E-Print Network [OSTI]

    Kamvar, Negin; Soroushfar, Saheb

    2015-01-01

    In this paper we consider a metric of a rotating black hole in conformal gravity. We calculate the thermodynamical quantities for this rotating black hole including Hawking temperature and entropy in four dimensional space-time, as we obtain the effective value of Komar angular momentum. The result is valid on the event horizon of the black hole, and at any radial distance out of it. Also we verify that the first law of thermodynamics will be held for this type of black hole.

  11. Results of CC Follow-Up in the G. Rollie White Building 

    E-Print Network [OSTI]

    Liu, C.; Turner, W. D.; Claridge, D. E.; Deng, S.; Bruner, H. L.

    2002-01-01

    of energy consumption of G. Rollie White Coliseum included energy consumption and HVAC system operation data analysis, measurement on HVAC systems, and examination of the control program. HVAC hardware problems, HVAC operation problems, and control program...

  12. White Grubs in Texas Turfgrass 

    E-Print Network [OSTI]

    Merchant, Michael E.; Biles, Stephen; Mott, Dale

    2004-06-24

    . Use of mulching mowers to recycle grass clippings should not cause thatch buildup in regularly mowed lawns. Environmental Considerations. Unnecessary insecticide applica- tions sometimes create more prob- lems than they solve. Pesticides can have... and other culti- vated plants. White grubs, sometimes referred to as grubworms, injure turf by feed- ing on roots and other under- ground plant parts. Damaged areas within lawns lose vigor and turn brown (Figure 1). Severely dam- aged turf can be lifted...

  13. Recovery Boiler Modeling: An Improved Char Burning Model Including Sulfate Reduction and Carbon Removal 

    E-Print Network [OSTI]

    Grace, T. M.; Wag, K. J.; Horton, R. R.; Frederick, W. J.

    1994-01-01

    This paper describes an improved model of char burning during black liquor combustion that is capable of predicting net rates of sulfate reduction to sulfide as well as carbon burnup rates. Enhancements include a proper ...

  14. The ages of very cool hydrogen-rich white dwarfs

    E-Print Network [OSTI]

    M. Salaris; E. Garcia-Berro; M. Hernanz; J. Isern; D. Saumon

    2000-07-04

    The evolution of white dwarfs is essentially a cooling process that depends primarily on the energy stored in their degenerate cores and on the transparency of their envelopes. In this paper we compute accurate cooling sequences for carbon-oxygen white dwarfs with hydrogen dominated atmospheres for the full range of masses of interest. For this purpose we use the most accurate available physical inputs for both the equation of state and opacities of the envelope and for the thermodynamic quantities of the degenerate core. We also investigate the role of the latent heat in the computed cooling sequences. We present separately cooling sequences in which the effects of phase separation of the carbon-oxygen binary mixture upon crystallization have been neglected, and the delay introduced in the cooling times when this mechanism is properly taken into account, in order to compare our results with other published cooling sequences which do not include a treatment of this phenomenon. We find that the cooling ages of very cool white dwarfs with pure hydrogen atmospheres have been systematically underestimated by roughly 1.5 Gyr at log(L/Lo)=-4.5 for an otherwise typical 0.6 Mo white dwarf, when phase separation is neglected. If phase separation of the binary mixture is included then the cooling ages are further increased by roughly 10%. Cooling tracks and cooling isochrones in several color-magnitude diagrams are presented as well.

  15. arXiv:physics/0203031 Non-white noise and a multiple-rate Markovian closure theory for turbulence

    E-Print Network [OSTI]

    Hammett, Greg

    parameters, to allow for a more accurate model of e#11;ects such as non-white noise. (As will be discussed in some cases a#11;ords a more accurate treatment of e#11;ects such as non-white noise), while retaining more below, the RMC does include more non- white-noise e#11;ects than one might think at #12;rst

  16. PURDUE UNIVERSITY BLACK CULTURAL CENTER

    E-Print Network [OSTI]

    Pittendrigh, Barry

    traveled to Detroit, Michigan to study our fall research theme, " Black Detroit: The History, Movement

  17. Black Holes and Galaxy Evolution

    E-Print Network [OSTI]

    David Merritt

    1999-10-29

    Supermassive binary black holes and their influence on the structure and evolution of galaxies is reviewed.

  18. Accretion onto the First Stellar Mass Black Holes

    E-Print Network [OSTI]

    Marcelo A. Alvarez; John H. Wise; Tom Abel

    2008-11-07

    The first stars in the universe, forming at redshifts z>15 in minihalos with masses of order 10^6 Msun, may leave behind black holes as their remnants. These objects could conceivably serve as "seeds" for much larger black holes observed at redshifts z~6. We study the growth of the remnant black holes through accretion including for the first time the emitted accretion radiation with adaptive mesh refinement cosmological radiation-hydrodynamical simulations. The effects of photo-ionization and heating dramatically affect the accretion flow from large scales, resulting in negligible mass growth of the black hole. We compare cases with the accretion luminosity included and neglected to show that the accretion radiation drastically changes the environment within 100 pc of the black hole, where gas temperatures are increased by an order of magnitude. The gas densities are reduced and further star formation in the same minihalo prevented for the two hundred million years of evolution we followed. These calculations show that even without the radiative feedback included most seed black holes do not gain mass as efficiently as has been hoped for in previous theories, implying that black hole remnants of Pop III stars that formed in minihalos are not likely to be the origin of miniquasars. Most importantly, however, these calculations demonstrate that if early stellar mass black holes are indeed accreting close to the Bondi-Hoyle rate with ten percent efficiency they have a dramatic local effect in regulating star formation in the first galaxies.

  19. A review of "Versions of Blackness: Key Texts on Slavery from the Seventeenth Century" edited by Derek Hughes 

    E-Print Network [OSTI]

    M'Baye, Babacar

    2009-01-01

    the Seventeenth Century. Cambridge, UK: Cambridge UP, 2007. V + 381 pp. Paperback $24. Review by babacar m?baye, kent state university Derek Hughes? Versions of Blackness: Key Texts on Slavery from the Seventeenth Century brings together important European... Europeans either enslaved, massacred, or colonized The book?s major objective is to resist the revisionist practice of interpreting the past mainly through the lenses of modern theories of racial interactions between blacks and whites. Opposing...

  20. Countries Gasoline Prices Including Taxes

    Gasoline and Diesel Fuel Update (EIA)

    Crude oil, gasoline, heating oil, diesel, propane, and other liquids including biofuels and natural gas liquids. Natural Gas Exploration and reserves, storage, imports and...

  1. White House honors Los Alamos

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking WithTelecentricNCubicthe FOIA? The FOIA,Department of EnergyWhite

  2. CHARYBDIS: A Black Hole Event Generator

    E-Print Network [OSTI]

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

    2003-07-29

    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.

  3. Gaia - A White Dwarf Discovery Machine

    E-Print Network [OSTI]

    Stefan Jordan

    2006-10-30

    The Gaia data will help to improve the construction of a luminosity function for the disk and the halo and will provide a more accurate determination of the age of our solar neighborhood. Moreover, reliable stellar dynamical investigations of the disk and halo components will be possible. For the first time it will be possible to test the mass-radius relation of white dwarfs in great detail. Moreover, more accurate masses of magnetic and cool white dwarfs can be expected. Gaia is also expected to discover many new pulsating white dwarfs. The Gaia measurements can also complement the measurements of gravitational waves from close white dwarf binaries with Lisa.

  4. Wind Turbine Acoustic Noise A white paper

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    Wind Turbine Acoustic Noise A white paper Prepared by the Renewable Energy Research Laboratory...................................................................... 8 Sound from Wind Turbines .............................................................................................. 10 Sources of Wind Turbine Sound

  5. The White House's Week of Making

    Broader source: Energy.gov [DOE]

    The White House's Week of Making from June 12-18 will coincide with a National Maker Faire event in Washington, D.C.

  6. Black Hole Thermodynamics in Modified Gravity

    E-Print Network [OSTI]

    Jonas R. Mureika; John W. Moffat; Mir Faizal

    2015-03-03

    We analyze the thermodynamics of a non-rotating and rotating black hole in a modified theory of gravity that includes scalar and vector modifications to general relativity, which results in a modified gravitational constant $G = G_N(1+\\alpha)$ and a new gravitational charge $Q = \\sqrt{\\alpha G_N}M$. The influence of the parameter $\\alpha$ alters the non-rotating black hole's lifetime, temperature and entropy profiles from the standard Schwarzschild case. The thermodynamics of a rotating black hole is analyzed and it is shown to possess stable, cold remnants. The thermodynamic properties of a vacuum solution regular at $r=0$ are investigated and the solution without a horizon called a "gray hole" is not expected to possess an information loss problem.

  7. Neutralino relic density including coannihilations

    E-Print Network [OSTI]

    Paolo Gondolo; Joakim Edsjo

    1997-11-25

    We give an overview of our precise calculation of the relic density of the lightest neutralino, in which we included relativistic Boltzmann averaging, subthreshold and resonant annihilations, and coannihilation processes with charginos and neutralinos.

  8. The Environmental Impact of Supermassive Black Holes

    E-Print Network [OSTI]

    Abraham Loeb

    2004-08-10

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

  9. White dwarf mergers,White dwarf mergers, thermonuclear supernovae,thermonuclear supernovae,

    E-Print Network [OSTI]

    Hinton, Jim

    White dwarf mergers,White dwarf mergers, thermonuclear supernovae,thermonuclear supernovae fusion is ignited. Degenerate, hence runaway. #12;CO white dwarf accretes, either from companion, or from disk after merger. As it approaches maximum mass, C fusion is ignited. Degenerate, hence runaway. SN Ia

  10. GASTROINTESTINAL MORPHOLOGY OF FEMALE WHITE-TAILED AND MULE DEER: EFFECTS OF FIRE,

    E-Print Network [OSTI]

    may be directly associated with size. Key words: Black Hills, digesta, fire, intestines, mule deer papillation has been studied in a variety of wild ungulates including elk (Cervus elaphus-- Lentle et al. 1996

  11. ENERGY WHITE PAPER Our energy future -

    E-Print Network [OSTI]

    ENERGY WHITE PAPER Our energy future - creating a low carbon economy and consumers. And we stand up for fair and open markets in the UK, Europe and the world. #12;Our energy future ENERGY WHITE PAPER Our energy future - creating a low carbon economy 1 Foreword

  12. Black Holes In Astronomy Black Holes In Astronomy

    E-Print Network [OSTI]

    Wagner, Stephan

    Black Hole horizon static limit ergosphere radiation magnetic fields jet jet #12;Black-hole accretion with a central bulge. #12;Click to edit Master text styles Second level Third level Fourth level Fifth level Jets and lobes of Cygnus A Carilli et al. Supermassive black holes are the most powerful engines in the Universe

  13. The renaissance of black phosphorus

    E-Print Network [OSTI]

    Ling, Xi

    One hundred years after its first successful synthesis in the bulk form in 1914, black phosphorus (black P) was recently rediscovered from the perspective of a 2D layered material, attracting tremendous interest from ...

  14. Area products for black hole horizons

    E-Print Network [OSTI]

    Visser, Matt

    2013-01-01

    Area products for multi-horizon black holes often have intriguing properties, and are often independent of the mass of the black hole (depending only on various charges, angular momenta, and moduli). Such products are often formulated in terms of the areas of inner (Cauchy) horizons and event horizons, and often include the effects of unphysical "virtual'" horizons. For the Schwarzschild-de Sitter [Kottler] black hole in (3+1) dimensions it is shown by explicit exact calculation that the product of event horizon area and cosmological horizon area is not mass independent. (Including the effect of the third "virtual" horizon does not improve the situation.) Similarly, in the Reissner-Nordstrom-anti-de Sitter black hole in (3+1) dimensions the product of inner (Cauchy) horizon area and event horizon area is calculated (perturbatively), and is shown to be not mass independent. That is, the mass-independence of the product of physical horizon areas is not generic. In the generic situation, whenever the quasi-local...

  15. Electric Charge in Interaction with Magnetically Charged Black Holes

    E-Print Network [OSTI]

    J. H. Kim; Sei-Hoon Moon

    2007-10-02

    We examine the angular momentum of an electric charge e placed at rest outside a dilaton black hole with magnetic charge Q. The electromagnetic angular momentum which is stored in the electromagnetic field outside the black hole shows several common features regardless of the dilaton coupling strength, though the dilaton black holes are drastically different in their spacetime structure depending on it. First, the electromagnetic angular momentum depends on the separation distance between the two objects and changes monotonically from eQ to 0 as the charge goes down from infinity to the horizon, if rotational effects of the black hole are discarded. Next, as the black hole approaches extremality, however, the electromagnetic angular momentum tends to be independent of the distance between the two objects. It is then precisely $eQ$ as in the electric charge and monopole system in flat spacetime. We discuss why these effects are exhibited and argue that the above features are to hold in widely generic settings including black hole solutions in theories with more complicated field contents, by addressing the no hair theorem for black holes and the phenomenon of field expulsion exhibited by extremal black holes.

  16. Black Holes And Their Entropy 

    E-Print Network [OSTI]

    Mei, Jianwei

    2010-10-12

    . . . . . . . . . 21 1. Solutions in Four Dimensions . . . . . . . . . . . . . . 22 2. Solutions in Higher Dimensions . . . . . . . . . . . . . 27 C. Black Hole Solutions in Supergravity Theories . . . . . . . 30 D. Plebanski-Demianski Type Solutions in d = 5... is to discuss the construction of new black hole solutions and the calculation of the black hole entropy. In Chapter II, we shall re- port some new black hole solutions that we have found during the past few years [21, 22, 23] and we will discuss some...

  17. Measurement of Mass and Spin of Black Holes with QPOs

    E-Print Network [OSTI]

    B. Aschenbach

    2007-10-18

    There are now four low mass X-ray binaries with black holes which show twin resonant-like HFQPOs. Similar QPOs might have been found in Sgr A*. I review the power spectral density distributions of the three X-ray flares and the six NIR flares published for Sgr A* so far, in order to look for more similarities than just the frequencies between the microquasar black holes and Sgr A*. The three X-ray flares of Sgr A* are re-analysed in an identical way and white noise probabilities from their power density distributions are given for the periods reported around 1100 s. Progress of the resonant theory using the anomalous orbital velocity effect is summarized.

  18. Barriers to CHP with Renewable Portfolio Standards, Draft White...

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

    Barriers to CHP with Renewable Portfolio Standards, Draft White Paper, September 2007 Barriers to CHP with Renewable Portfolio Standards, Draft White Paper, September 2007 The...

  19. White House Announces New Executive Order To Reduce Greenhouse...

    Energy Savers [EERE]

    White House Announces New Executive Order To Reduce Greenhouse Gas Emissions in the Federal Government White House Announces New Executive Order To Reduce Greenhouse Gas Emissions...

  20. White House Highlights New DOE Measures to Advance Renewable...

    Energy Savers [EERE]

    White House Highlights New DOE Measures to Advance Renewable Energy Deployment and Increase Energy Efficiency White House Highlights New DOE Measures to Advance Renewable Energy...

  1. Sandia Energy - Four-color laser white illuminant demonstrating...

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

    laser white illuminant demonstrating high color-rendering quality Home Solid-State Lighting News Four-color laser white illuminant demonstrating high color-rendering quality...

  2. Rocky Mountain White Tilapia Aquaculture Low Temperature Geothermal...

    Open Energy Info (EERE)

    Rocky Mountain White Tilapia Aquaculture Low Temperature Geothermal Facility Jump to: navigation, search Name Rocky Mountain White Tilapia Aquaculture Low Temperature Geothermal...

  3. White House Spotlights Solar Innovation as Summit Registration...

    Energy Savers [EERE]

    White House Spotlights Solar Innovation as Summit Registration Continues White House Spotlights Solar Innovation as Summit Registration Continues April 23, 2014 - 10:38am Addthis...

  4. Tribal Leaders Provide White House with Input on Bolstering Climate...

    Energy Savers [EERE]

    Tribal Leaders Provide White House with Input on Bolstering Climate Resilience Tribal Leaders Provide White House with Input on Bolstering Climate Resilience January 7, 2015 -...

  5. The Evolution of Accreting Black Holes in Outburst

    E-Print Network [OSTI]

    John A. Tomsick

    2004-01-12

    Black hole binaries exhibit dramatic changes in their X-ray spectral and timing properties over time, providing important clues about the physical processes that occur in these systems. Black holes and black hole candidates are prime targets for RXTE with observational goals including the study of extreme gravitational fields and jet formation mechanisms. The great wealth of data from RXTE has helped us to learn about these systems as well as raising new questions about accreting black holes. RXTE observations have allowed us to study a wide range of black hole science topics including the connection between the accretion disk and jets, the geometry of the inner accretion flow, and the physical changes that occur between spectral states. In this presentation, I discuss significant results on these topics that have been obtained for persistent and transient black holes over the past several years, and I present results from our program of X-ray and radio observations during the decays of black hole transient outbursts.

  6. Black Holes at Accelerators

    E-Print Network [OSTI]

    Bryan Webber

    2006-04-06

    In theories with large extra dimensions and TeV-scale gravity, black holes are copiously produced in particle collisions at energies well above the Planck scale. I briefly review some recent work on the phenomenology of this process, with emphasis on theoretical uncertainties and possible strategies for measuring the number of extra dimensions.

  7. Quantum black hole inflation

    E-Print Network [OSTI]

    M. B. Altaie

    2001-05-07

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

  8. Gasification of black liquor

    DOE Patents [OSTI]

    Kohl, Arthur L. (Woodland Hills, CA)

    1987-07-28

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

  9. Gasification of black liquor

    DOE Patents [OSTI]

    Kohl, A.L.

    1987-07-28

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

  10. Statistical Mechanics of Black Holes

    E-Print Network [OSTI]

    B. Harms; Y. Leblanc

    1992-05-11

    We analyze the statistical mechanics of a gas of neutral and charged black holes. The microcanonical ensemble is the only possible approach to this system, and the equilibrium configuration is the one for which most of the energy is carried by a single black hole. Schwarzschild black holes are found to obey the statistical bootstrap condition. In all cases, the microcanonical temperature is identical to the Hawking temperature of the most massive black hole in the gas. U(1) charges in general break the bootstrap property. The problems of black hole decay and of quantum coherence are also addressed.

  11. Identification of Astrophysical Black Holes

    E-Print Network [OSTI]

    Sandip K. Chakrabarti

    1998-03-19

    Black holes are by definition black, and therefore cannot be directly observed by using electromagnetic radiations. Convincing identification of black holes must necessarily depend on the identification of a very specially behaving matter and radiation which surround them. A major problem in this subject of black hole astrophysics is to quantify the behaviour of matter and radiation close to the horizon. In this review, the subject of black hole accretion and outflow is systematically developed. It is shown that both the stationary as well as the non-stationary properties of the observed spectra could be generally understood by these solutions. It is suggested that the solutions of radiative hydrodynamic equations may produce clear spectral signatures of black holes. Other circumstantial evidences of black holes, both in the galactic centers as well as in binary systems, are also presented.

  12. Brief review on higher spin black holes

    E-Print Network [OSTI]

    Alfredo Perez; David Tempo; Ricardo Troncoso

    2014-05-12

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

  13. History of Electricity at the White House

    Broader source: Energy.gov [DOE]

    The White House has only been electrified for a little over a century. Check out our timeline to read more about what it takes to power 1600 Pennsylvania Avenue.

  14. Low Luminosity Companions to White Dwarfs

    E-Print Network [OSTI]

    J. Farihi; E. E. Becklin; B. Zuckerman

    2005-11-16

    This paper presents results of a near-infrared imaging survey for low mass stellar and substellar companions to white dwarfs. A wide field proper motion survey of 261 white dwarfs was capable of directly detecting companions at orbital separations between $\\sim100$ and 5000 AU with masses as low as 0.05 $M_{\\odot}$, while a deep near field search of 86 white dwarfs was capable of directly detecting companions at separations between $\\sim50$ and 1100 AU with masses as low as 0.02 $M_{\\odot}$. Additionally, all white dwarf targets were examined for near-infrared excess emission, a technique capable of detecting companions at arbitrarily close separations down to masses of 0.05 $M_{\\odot}$. No brown dwarf candidates were detected, which implies a brown dwarf companion fraction of $main sequence binary interactions.

  15. BPA research aids Columbia River white sturgeon

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

    research aids Columbia River white sturgeon 8142015 12:00 AM Tweet Page Content BPA fish biologist Scott Bettin (left) and Brad Cady of the Washington Dept. of Fish and...

  16. Strategic Facility Management: A White Paper

    Broader source: Energy.gov [DOE]

    This white paper provides information on the SFP process, its requirements and benefits, and gives a facility manager the basic tools to launch and successfully complete a SFP for the supported organization.

  17. Lighting Choices - White Background | Department of Energy

    Energy Savers [EERE]

    Choices - White Background Image icon All of these lightbulbs-CFLs, LEDs, and energy-saving incandescents-meet the new energy standards that take effect from 2012-2014. More...

  18. 2014 White House Tribal Nations Conference

    Office of Energy Efficiency and Renewable Energy (EERE)

    On Wednesday, December 3, President Obama will host the 2014 White House Tribal Nations Conference at the Capital Hilton in Washington, DC. The conference will provide leaders from the 566...

  19. CELLULAR TELEPHONE FACILITIES A White Paper

    E-Print Network [OSTI]

    California at Santa Barbara, University of

    1 CELLULAR TELEPHONE FACILITIES ON CAMPUS A White Paper May 1, 2003 #12;2 TABLE OF CONTENTS Background on Cellular Telephones.......................................................... 5 History of Cellular Telephone Sites on Campus.............................................. 7 Current Terms

  20. NGNP High Temperature Materials White Paper

    SciTech Connect (OSTI)

    Lew Lommers; George Honma

    2012-08-01

    This white paper is one in a series of white papers that address key generic issues of the combined construction and operating license (COL) pre-application program key generic issues for the Next Generation Nuclear Plant reactor using the prismatic block fuel technology. The purpose of the pre-application program interactions with the NRC staff is to reduce the time required for COL application review by identifying and addressing key regulatory issues and, if possible, obtaining agreements for their resolution

  1. Black Hole Scan

    E-Print Network [OSTI]

    Juan Crisostomo; Ricardo Troncoso; Jorge Zanelli

    2000-09-22

    Gravitation theories selected by requiring that they have a unique anti-de Sitter vacuum with a fixed cosmological constant are studied. For a given dimension d, the Lagrangians under consideration are labeled by an integer k=1,2,...,[(d-1)/2]. Black holes for each d and k are found and are used to rank these theories. A minimum possible size for a localized electrically charged source is predicted in the whole set of theories, except General Relativity. It is found that the thermodynamic behavior falls into two classes: If d-2k=1, these solutions resemble the three dimensional black hole, otherwise, their behavior is similar to the Schwarzschild-AdS_4 geometry.

  2. Black holes at accelerators.

    E-Print Network [OSTI]

    Webber, Bryan R

    be presented and the effects of some of the uncertainties can be investigated. 3.1. Hawking Spectrum With the above assumptions, the spectrum of particles emitted during black hole decay takes the form dN dE ? ?E2 (eE/TH ? 1) T n+6H (8) where as usual... the trapped surface area [6, 7]. T030 02 4 6 8 10 0 0.2 0.4 0.6 0.8 1 1.2 n=0 n=1 n=2 n=6 E rS ?ˆ (0 ) ab s/ pi r2 S Figure 4: Grey-body factors for scalar emission on the brane from a (4 + n)D black hole. 0 2 4 6 8 10 0 0.2 0.4 0.6 0.8 1 1.2 n=0 n=1 n=2 n=6 E...

  3. Black Hole Demographics

    E-Print Network [OSTI]

    Laura Ferrarese

    2002-03-04

    The purpose of this contribution is to review the current status of black hole demographics in light of recent advances in the study of high redshift QSOs (section 2), local AGNs (section 3) and local quiescent galaxies (section 4). I will then outline the prospects for future progress (section 5), and discuss what I believe will be the challenges for the years to come [ABRIDGED].

  4. THE POST-MERGER MAGNETIZED EVOLUTION OF WHITE DWARF BINARIES: THE DOUBLE-DEGENERATE CHANNEL OF SUB-CHANDRASEKHAR TYPE Ia SUPERNOVAE AND THE FORMATION OF MAGNETIZED WHITE DWARFS

    SciTech Connect (OSTI)

    Ji Suoqing; Fisher, Robert T. [University of Massachusetts Dartmouth, Department of Physics, 285 Old Westport Road, North Dartmouth, MA 02740 (United States); Garcia-Berro, Enrique [Departament de Fisica Aplicada, Universitat Politecnica de Catalunya, c/Esteve Terrades, 5, E-08860 Castelldefels (Spain); Tzeferacos, Petros; Jordan, George; Lee, Dongwook [Center for Astrophysical Thermonuclear Flashes, The University of Chicago, Chicago, IL 60637 (United States); Loren-Aguilar, Pablo [School of Physics, University of Exeter, Stocker Road, Exeter EX4 4QL (United Kingdom); Cremer, Pascal [Bethe Center for Theoretical Physics, Universitaet Bonn, Nussallee 12, D-53115 Bonn (Germany); Behrends, Jan [Fachbereich Physik, Freie Universitaet Berlin, Arnimallee 14, D-14195 Berlin (Germany)

    2013-08-20

    Type Ia supernovae (SNe Ia) play a crucial role as standardizable cosmological candles, though the nature of their progenitors is a subject of active investigation. Recent observational and theoretical work has pointed to merging white dwarf binaries, referred to as the double-degenerate channel, as the possible progenitor systems for some SNe Ia. Additionally, recent theoretical work suggests that mergers which fail to detonate may produce magnetized, rapidly rotating white dwarfs. In this paper, we present the first multidimensional simulations of the post-merger evolution of white dwarf binaries to include the effect of the magnetic field. In these systems, the two white dwarfs complete a final merger on a dynamical timescale, and are tidally disrupted, producing a rapidly rotating white dwarf merger surrounded by a hot corona and a thick, differentially rotating disk. The disk is strongly susceptible to the magnetorotational instability (MRI), and we demonstrate that this leads to the rapid growth of an initially dynamically weak magnetic field in the disk, the spin-down of the white dwarf merger, and to the subsequent central ignition of the white dwarf merger. Additionally, these magnetized models exhibit new features not present in prior hydrodynamic studies of white dwarf mergers, including the development of MRI turbulence in the hot disk, magnetized outflows carrying a significant fraction of the disk mass, and the magnetization of the white dwarf merger to field strengths {approx}2 Multiplication-Sign 10{sup 8} G. We discuss the impact of our findings on the origins, circumstellar media, and observed properties of SNe Ia and magnetized white dwarfs.

  5. TOWARD A SPECTROSCOPIC CENSUS OF WHITE DWARFS WITHIN 40 pc OF THE SUN

    SciTech Connect (OSTI)

    Limoges, M.-M.; Bergeron, P.; Lepine, S. E-mail: bergeron@astro.umontreal.ca

    2013-05-15

    We present the preliminary results of a survey aimed at significantly increasing the range and completeness of the local census of spectroscopically confirmed white dwarfs. The current census of nearby white dwarfs is reasonably complete only to about 20 pc of the Sun, a volume that includes around 130 white dwarfs, a sample too small for detailed statistical analyses. This census is largely based on follow-up investigations of stars with very large proper motions. We describe here the basis of a method that will lead to a catalog of white dwarfs within 40 pc of the Sun and north of the celestial equator, thus increasing by a factor of eight the extent of the northern sky census. White dwarf candidates are identified from the SUPERBLINK proper motion database, allowing us to investigate stars down to a proper motion limit {mu} > 40 mas yr{sup -1}, while minimizing the kinematic bias for nearby objects. The selection criteria and distance estimates are based on a combination of color-magnitude and reduced proper motion diagrams. Our follow-up spectroscopic observation campaign has so far uncovered 193 new white dwarfs, among which we identify 127 DA (including 9 DA+dM and 4 magnetic), 1 DB, 56 DC, 3 DQ, and 6 DZ stars. We perform a spectroscopic analysis on a subsample of 84 DAs, and provide their atmospheric parameters. In particular, we identify 11 new white dwarfs with spectroscopic distances within 25 pc of the Sun, including five candidates to the D < 20 pc subset.

  6. Physical Properties of the Current Census of Northern White Dwarfs within 40 pc of the Sun

    E-Print Network [OSTI]

    Limoges, M -M; Lépine, S

    2015-01-01

    We present a detailed description of the physical properties of our current census of white dwarfs within 40 pc of the Sun, based on an exhaustive spectroscopic survey of northern hemisphere candidates from the SUPERBLINK proper motion database. Our method for selecting white dwarf candidates is based on a combination of theoretical color-magnitude relations and reduced proper motion diagrams. We reported in an earlier publication the discovery of nearly 200 new white dwarfs, and we present here the discovery of an additional 133 new white dwarfs, among which we identify 96 DA, 3 DB, 24 DC, 3 DQ, and 7 DZ stars. We further identify 178 white dwarfs that lie within 40 pc of the Sun, representing a 40% increase of the current census, which now includes 492 objects. We estimate the completeness of our survey at between 66 and 78%, allowing for uncertainties in the distance estimates. We also perform a homogeneous model atmosphere analysis of this 40 pc sample and find a large fraction of massive white dwarfs, in...

  7. Spitzer IRAC Observations of White Dwarfs. II. Massive Planetary and Cold Brown Dwarf Companions to Young and Old Degenerates

    E-Print Network [OSTI]

    J. Farihi; E. E. Becklin; B. Zuckerman

    2008-05-13

    This paper presents a sensitive and comprehensive IRAC 3-8 $\\mu$m photometric survey of white dwarfs for companions in the planetary mass regime with temperatures cooler than the known T dwarfs. The search focuses on descendents of intermediate mass stars with $M\\ga3$ $M_{\\odot}$ whose inner, few hundred AU regions cannot be probed effectively for massive planets and brown dwarfs by any alternative existing method. Furthermore, examination for mid-infrared excess explores an extensive range of orbital semimajor axes, including the intermediate 5-50 AU range poorly covered and incompletely accessible by other techniques at main sequence or evolved stars. Three samples of white dwarfs are chosen which together represent relatively young as well as older populations of stars: 9 open cluster white dwarfs, 22 high mass field white dwarfs, and 17 metal-rich field white dwarfs. In particular, these targets include: 7 Hyads and 4 field white dwarfs of similar age; 1 Pleiad and 19 field white dwarfs of similar age; van Maanen 2 and 16 similarly metal-rich white dwarfs with ages between 1 and 7 Gyr. No substellar companion candidates were identified at any star. By demanding a 15% minimum photometric excess at 4.5 $\\mu$m to indicate a companion detection, upper limits in the planetary mass regime are established at 34 of the sample white dwarfs, 20 of which have limits below 10 $M_{\\rm J}$ according to substellar cooling models. Specifically, limits below the minimum mass for deuterium burning are established at all Pleiades and Hyadeswhite dwarfs, as well as similarly young field white dwarfs, half a dozen of which receive limits at or below 5 $M_{\\rm J}$. Two IRAC epochs at vMa 2 rule out $T\\ga200$ K proper motion companions within 1200 AU.

  8. #include #include

    E-Print Network [OSTI]

    Kessler, Christoph

    ] (where a[n] = +infty). C's * bsearch() can't be used, it requires a[j]==key. */ int findloc( void *key Combine­CRCW BSP­Quicksort * variant by Gerbessiotis/Valiant JPDC 22(1994) * implemented in NestStep­C. */ int N=10; // default value /** findloc(): find largest index j in [0..n­1] with * a[j

  9. Black holes in general relativity

    E-Print Network [OSTI]

    Visser, Matt

    2009-01-01

    What is going on (as of August 2008) at the interface between theoretical general relativity, string-inspired models, and observational astrophysics? Quite a lot. In this mini-survey I will make a personal choice and focus on four specific questions: Do black holes "exist"? (For selected values of the word "exist".) Is black hole formation and evaporation unitary? Can one mimic a black hole to arbitrary accuracy? Can one detect the presence of a horizon using local physics?

  10. Magnetic wormholes and black universes with invisible ghosts

    E-Print Network [OSTI]

    Bronnikov, K A

    2015-01-01

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

  11. Local free-fall temperature of a RN-AdS black hole

    E-Print Network [OSTI]

    Yong-Wan Kim; Jaedong Choi; Young-Jai Park

    2010-03-09

    We use the global embedding Minkowski space (GEMS) geometries of a (3+1)-dimensional curved Reissner-Nordstr\\"om(RN)-AdS black hole spacetime into a (5+2)-dimensional flat spacetime to define a proper local temperature, which remains finite at the event horizon, for freely falling observers outside a static black hole. Our extended results include the known limiting cases of the RN, Schwarzschild--AdS, and Schwarzschild black holes.

  12. Quantum Mechanics and Black Holes

    E-Print Network [OSTI]

    Jose N. Pecina-Cruz

    2005-11-27

    This paper discusses the existence of black holes from the foundations of quantum mechanics. It is found that quantum mechanics rule out a possible gravitational collapse.

  13. NASA LAW 2006 LABORATORY ASTROPHYSICS WHITE PAPER 1 LABORATORY ASTROPHYSICS WHITE PAPER

    E-Print Network [OSTI]

    Savin, Daniel Wolf

    NASA LAW 2006 LABORATORY ASTROPHYSICS WHITE PAPER 1 LABORATORY ASTROPHYSICS WHITE PAPER (BASED ON THE 2006 NASA LABORATORY ASTROPHYSICS WORKSHOP AT THE UNIVERSITY OF NEVADA, LAS VEGAS, 14-16 FEBRUARY, 2006 Chutjian (Jet Propulsion Laboratory), Gary Ferland (University of Ken- tucky), Steve Manson (Georgia State

  14. Phase transformations of nano-sized cubic boron nitride to white graphene and white graphite

    SciTech Connect (OSTI)

    Dang, Hongli; Liu, Yingdi; Xue, Wenhua; Anderson, Ryan S.; Sewell, Cody R. [Department of Physics and Engineering Physics, The University of Tulsa, Tulsa, Oklahoma 74104 (United States); Xue, Sha; Crunkleton, Daniel W. [Department of Chemical Engineering, The University of Tulsa, Tulsa, Oklahoma 74104 (United States); Institute of Alternate Energy, The University of Tulsa, Tulsa, Oklahoma 74104 (United States); Shen, Yaogen [Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Kowloon (Hong Kong); Wang, Sanwu, E-mail: sanwu-wang@utulsa.edu [Department of Physics and Engineering Physics, The University of Tulsa, Tulsa, Oklahoma 74104 (United States); Institute of Alternate Energy, The University of Tulsa, Tulsa, Oklahoma 74104 (United States)

    2014-03-03

    We report quantum-mechanical investigations that predict the formation of white graphene and nano-sized white graphite from the first-order phase transformations of nano-sized boron nitride thin-films. The phase transformations from the nano-sized diamond-like structure, when the thickness d?>?1.4?nm, to the energetically more stable nano-sized white graphite involve low activation energies of less than 1.0?eV. On the other hand, the diamond-like structure transforms spontaneously to white graphite when d???1.4?nm. In particular, the two-dimensional structure with single-layer boron nitride, the so-called white graphene, could be formed as a result of such transformation.

  15. Why Blue-Collar Blacks Help Less

    E-Print Network [OSTI]

    Smith, Sandra Susan; Young, Kara Alexis

    2013-01-01

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

  16. Dermoscopy of black-spot poison ivy

    E-Print Network [OSTI]

    Rader, Ryan K; Mu, Ruipu; Shi, Honglan; Stoecker, William V; Hinton, Kristen A

    2012-01-01

    CT, Bean AS. Black-spot poison ivy: A rare phenomenon. J AmJG, Lucky AW. Black spot poison ivy: A report of 5 cases andis unique for black-spot poison ivy. The UFLC-MS/MS urushiol

  17. Green, Black, Lean Six Sigma and Master Black Belt Certifications

    E-Print Network [OSTI]

    Grissino-Mayer, Henri D.

    Green, Black, Lean Six Sigma and Master Black Belt Certifications Green BeLt CertifiCation Candidates may choose from three Green Belts offered: 1) Lean (one week of coursework) 2) Lean Six Sigma (two weeks of coursework) 3) Six Sigma (two weeks of coursework) Green Belt certification is a two

  18. Efficient White SSL Component for General Illumination

    SciTech Connect (OSTI)

    Sean Evans

    2011-01-31

    Cree has developed a new, high-efficiency, low-cost, light emitting diode (LED) module that should be capable of replacing standard, halogen, fluorescent and metal halide lamps based on the total cost of ownership. White LEDs are produced by combining one or more saturated color LEDs with a phosphor or other light down-converting media to achieve white broad-band illumination. This two year project addressed LED chip, package and phosphor efficiency improvements to establish a technology platform suitable for low-cost, high-efficiency commercial luminaires. New phosphor materials with improved quantum efficiency at 'real-life' operating conditions were developed along with new package technology to improve the efficiency of warm white LED modules compared to the baseline technology. Specifically, Cree has successfully demonstrated warm white LED modules providing 540 lumens at a correlated color temperature (CCT) of 3000 K. The LED module had an efficacy of 102.8 lumens per watt (LPW) using 1 mm2 chips biased at 350 mA - a 27% improvement over the technology at project start (81 LPW at 3000K). The white modules also delivered an efficacy of 88 LPW at elevated junction temperatures of 125 C. In addition, a proof-of-concept 4-inch downlight luminaire produced a flux of 1183 lumens at a CCT of 2827 K and a color rendering index (CRI) of 80 using this project's phosphor developments.

  19. Thermal BEC black holes

    E-Print Network [OSTI]

    Roberto Casadio; Andrea Giugno; Octavian Micu; Alessio Orlandi

    2015-11-04

    We review some features of BEC models of black holes obtained by means of the HWF formalism. We consider the KG equation for a toy graviton field coupled to a static matter current in spherical symmetry. The classical field reproduces the Newtonian potential generated by the matter source, while the corresponding quantum state is given by a coherent superposition of scalar modes with continuous occupation number. An attractive self-interaction is needed for bound states to form, so that (approximately) one mode is allowed, and the system of N bosons can be self-confined in a volume of the size of the Schwarzschild radius. The HWF is then used to show that the radius of such a system corresponds to a proper horizon. The uncertainty in the size of the horizon is related to the typical energy of Hawking modes: it decreases with the increasing of the black hole mass (larger number of gravitons), in agreement with semiclassical calculations and different from a single very massive particle. The spectrum contains a discrete ground state of energy $m$ (the bosons forming the black hole), and a continuous spectrum with energy $\\omega > m$ (representing the Hawking radiation and modelled with a Planckian distribution at the expected Hawking temperature). The $N$-particle state can be collectively described by a single-particle wave-function given by a superposition of a total ground state with energy $M = N m$ and a Planckian distribution for $E > M$ at the same Hawking temperature. The partition function is then found to yield the usual area law for the entropy, with a logarithmic correction related with the Hawking component. The backreaction of modes with $\\omega > m$ is also shown to reduce the Hawking flux and the evaporation properly stops for vanishing mass.

  20. Maximum mass of stable magnetized highly super-Chandrasekhar white dwarfs: stable solutions with varying magnetic fields

    SciTech Connect (OSTI)

    Das, Upasana; Mukhopadhyay, Banibrata, E-mail: upasana@physics.iisc.ernet.in, E-mail: bm@physics.iisc.ernet.in [Department of Physics, Indian Institute of Science, Bangalore 560012 (India)

    2014-06-01

    We address the issue of stability of recently proposed significantly super-Chandrasekhar white dwarfs. We present stable solutions of magnetostatic equilibrium models for super-Chandrasekhar white dwarfs pertaining to various magnetic field profiles. This has been obtained by self-consistently including the effects of the magnetic pressure gradient and total magnetic density in a general relativistic framework. We estimate that the maximum stable mass of magnetized white dwarfs could be more than 3 solar mass. This is very useful to explain peculiar, overluminous type Ia supernovae which do not conform to the traditional Chandrasekhar mass-limit.

  1. Black Stars and Gamma Ray Bursts

    E-Print Network [OSTI]

    Tanmay Vachaspati

    2007-06-08

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

  2. Recombination energy in double white dwarf formation

    E-Print Network [OSTI]

    Nandez, Jose L A; Lombardi, James C

    2015-01-01

    In this Letter we investigate the role of recombination energy during a common envelope event. We confirm that taking this energy into account helps to avoid the formation of the circumbinary envelope commonly found in previous studies. For the first time, we can model a complete common envelope event, with a clean compact double white dwarf binary system formed at the end. The resulting binary orbit is almost perfectly circular. In addition to considering recombination energy, we also show that between 1/4 and 1/2 of the released orbital energy is taken away by the ejected material. We apply this new method to the case of the double-white dwarf system WD 1101+364, and we find that the progenitor system at the start of the common envelope event consisted of a $\\sim1.5M_\\odot$ red giant star in a $\\sim 30$ day orbit with a white dwarf companion.

  3. Black Holes of Negative Mass

    E-Print Network [OSTI]

    R. B. Mann

    1997-05-06

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

  4. Nonnative Lizards Nile Monitor 4 to 6 ft. Brown/yellow body bands; forked black/blue tongue; long sharp claws

    E-Print Network [OSTI]

    Mazzotti, Frank

    beneath the eye Reticulated Python 14 to 18 ft. Distinct reddish eyes; tan body with dark brown net dull with age. Males have larger spikes along back. Black and White Tegu 2 to 3 ft. Dark bands. Yellowish-tan to dark brown; red dewlap with yellow border Ianaré Sévi NATIVE Look-a-Likes David Barkasy

  5. White Wind Farms Strategic Communications Campaign

    E-Print Network [OSTI]

    Ford, Gina; Noulles, Mary; James, Jessica

    2014-09-03

    66053 Nearby Wine Retailers 11 Finances, Operations and Overhead In 2012, White Wind Farms generated $555,000 in annual revenue. The revenue is itemized as follows: $500,000 in nursery sales, $30,000 in wine sales and $25,000 in revenue from... Village, Kan., were the only three retail outlets where respondents purchased wine. 23 Social Eight respondents follow White Wind Farms on Facebook, 27 do not and the remaining 12 respondents do not utilize Facebook. When asked what types of occasions...

  6. Black Ge Based on Crystalline/Amorphous Core/Shell Nanoneedle Arrays

    E-Print Network [OSTI]

    Javey, Ali

    Black Ge Based on Crystalline/Amorphous Core/Shell Nanoneedle Arrays Yu-Lun Chueh,,§,|,# Zhiyong, ROC ABSTRACT Direct growth of black Ge on low-temperature substrates, including plastics and rubber is reported. The material is based on highly dense, crystalline/amorphous core/shell Ge nanoneedle arrays

  7. White(etching!matter!in!bearing!steel! Part1:!Controlled(cracking!of!52100!steel!

    E-Print Network [OSTI]

    Cambridge, University of

    ! quenched! and! untempered! steel! normally! used! in! the! manufacture! of! bearings.!The!varieties!of!cracks!studied!include!sparsely!distributed!martensite(lubricant!interactions,!or!hydrogen!trapping!can!be!studied!further.! ! Keywords:!bearing!steel,!indentation!cracks,!cracked!martensite,!grain(boundary!decohesion,! surface! 1! White(etching!matter!in!bearing!steel! Part1:!Controlled(cracking!of!52100!steel! ! W

  8. Bob-White Populations as Affected by Woodland Management in Eastern Texas. 

    E-Print Network [OSTI]

    Lay, Daniel W.

    1940-01-01

    NO. 592, TEXAS AGRICULTURAL EXPERIMENT STATION Table 1. Plant foods in 56 bob-white stomachs* taken in late winter. in Walker and Trinity counties, Texas Name of Plant ................................ Bush clover. Lespedeza striata... .................................. I>oveweed, Croton capzfafus ............. Green stuffs. including bur clover, chickweed, etc.. Rhynchosin sp. ............................................ ..................................... Menodora hrterophylln.. ......................... I...

  9. Nonlinearly charged Lifshitz black holes for any exponent $z>1$

    E-Print Network [OSTI]

    Abigail Alvarez; Eloy Ayón-Beato; Hernán A. González; Mokhtar Hassaïne

    2015-01-27

    Charged Lifshitz black holes for the Einstein-Proca-Maxwell system with a negative cosmological constant in arbitrary dimension $D$ are known only if the dynamical critical exponent is fixed as $z=2(D-2)$. In the present work, we show that these configurations can be extended to much more general charged black holes which in addition exist for any value of the dynamical exponent $z>1$ by considering a nonlinear electrodynamics instead of the Maxwell theory. More precisely, we introduce a two-parametric nonlinear electrodynamics defined in the more general, but less known, so-called $(\\mathcal{H},P)$-formalism and obtain a family of charged black hole solutions depending on two parameters. We also remark that the value of the dynamical exponent $z=D-2$ turns out to be critical in the sense that it yields asymptotically Lifshitz black holes with logarithmic decay supported by a particular logarithmic electrodynamics. All these configurations include extremal Lifshitz black holes. Charged topological Lifshitz black holes are also shown to emerge by slightly generalizing the proposed electrodynamics.

  10. The mass function of high redshift seed black holes

    E-Print Network [OSTI]

    Giuseppe Lodato; Priyamvada Natarajan

    2007-02-13

    In this paper we derive the mass function of seed black holes that result from the central mass concentrated via disc accretion in collapsed haloes at redshift $z\\approx 15$. Using standard arguments including stability, we show that these pre-galactic discs can assemble a significant mass concentration in the inner regions, providing fuel for the formation and initial growth of super-massive black holes. Assuming that these mass concentrations do result in central seed black holes, we determine the mass distribution of these seeds as a function of key halo properties. The seed mass distribution determined here turns out to be asymmetric and skewed to higher masses. Starting with these initial seeds, building up to $10^9$ solar masses by $z = 6$ to power the bright quasars is not a problem in the standard LCDM cosmogony. These seed black holes in gas rich environments are likely to grow into the supermassive black holes at later times via mergers and accretion. Gas accretion onto these seeds at high redshift will produce miniquasars that likely play an important role in the reionization of the Universe. Some of these seed black holes on the other hand could be wandering in galaxy haloes as a consequence of frequent mergers, powering the off-nuclear ultra-luminous X-ray sources detected in nearby galaxies.

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

    E-Print Network [OSTI]

    Meng-Sen Ma; Ren Zhao

    2014-11-04

    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.

  12. Comparing quantum black holes and naked singularities

    E-Print Network [OSTI]

    T. P. Singh

    2000-12-21

    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.

  13. Lagrangian perfect fluids and black hole mechanics

    E-Print Network [OSTI]

    Vivek Iyer

    1996-10-15

    The first law of black hole mechanics (in the form derived by Wald), is expressed in terms of integrals over surfaces, at the horizon and spatial infinity, of a stationary, axisymmetric black hole, in a diffeomorphism invariant Lagrangian theory of gravity. The original statement of the first law given by Bardeen, Carter and Hawking for an Einstein-perfect fluid system contained, in addition, volume integrals of the fluid fields, over a spacelike slice stretching between these two surfaces. When applied to the Einstein-perfect fluid system, however, Wald's methods yield restricted results. The reason is that the fluid fields in the Lagrangian of a gravitating perfect fluid are typically nonstationary. We therefore first derive a first law-like relation for an arbitrary Lagrangian metric theory of gravity coupled to arbitrary Lagrangian matter fields, requiring only that the metric field be stationary. This relation includes a volume integral of matter fields over a spacelike slice between the black hole horizon and spatial infinity, and reduces to the first law originally derived by Bardeen, Carter and Hawking when the theory is general relativity coupled to a perfect fluid. We also consider a specific Lagrangian formulation for an isentropic perfect fluid given by Carter, and directly apply Wald's analysis. The resulting first law contains only surface integrals at the black hole horizon and spatial infinity, but this relation is much more restrictive in its allowed fluid configurations and perturbations than that given by Bardeen, Carter and Hawking. In the Appendix, we use the symplectic structure of the Einstein-perfect fluid system to derive a conserved current for perturbations of this system: this current reduces to one derived ab initio for this system by Chandrasekhar and Ferrari.

  14. TECHNOLOGY READINESS LEVELS A White Paper

    E-Print Network [OSTI]

    Rhoads, James

    028 TECHNOLOGY READINESS LEVELS A White Paper April 6, 1995 John C. Mankins Advanced Concepts Office Office of Space Access and Technology NASA Introduction Technology Readiness Levels (TRLs) are a systematic metric/measurement system that supports assessments of the maturity of a particular technology

  15. Waste and Climate Change ISWA WHITE PAPER

    E-Print Network [OSTI]

    Columbia University

    ISWA Commitments 6 Introduction 7 Technologies 8 Material recovery 14 Organic recovery 16 Energy 38 2 List of Contents #12;The climate change phenomenon, its causes and consequences, is now to present the Waste & Climate ISWA White Paper, setting forth the technologies and mechanisms which can

  16. White Paper on Magnetic Fusion Program Strategies

    E-Print Network [OSTI]

    is uncertain. There are predictions of future energy shortages and of severe environmental impacts from present our vision for the future of fusion energy research. In this white paper, following a summary Institute of Technology Michael J. Saltmarsh Director, Fusion Energy Division Oak Ridge National Laboratory

  17. GREEN IT STRATEGY WHITE PAPER BIG DATA.

    E-Print Network [OSTI]

    Chou, James

    GREEN IT STRATEGY WHITE PAPER BIG DATA. BIG ENERGY. #12;GREEN:ons in MassachuseUs. In one day, Odyssey's cloud compu:ng power can process the same amount of 250 more kilowaUs annually. HARVARD'S GREEN IT COMMITMENT Achieve University

  18. Red Giant Red Giant White Giant

    E-Print Network [OSTI]

    Bechtold, Jill

    's enormous weight crushes the core with so much pressure that fusion is possible. Mass: 4 - 10 SM Star temperatures make the fusion of helium into carbon possible. Mass: 1 - 4 Solar Mass StarPower Points: 7 #12; High mass star that consumes hydrogen rapidly. White giants, such as Deneb in the constellation Cygnus

  19. Statement from the White House Press Secretary on the Ongoing...

    Office of Environmental Management (EM)

    Statement from the White House Press Secretary on the Ongoing U.S. Response to the Earthquakes and Tsunami in Japan Statement from the White House Press Secretary on the Ongoing...

  20. VBH-0068- In the Matter of Ronald D. White

    Broader source: Energy.gov [DOE]

    This Decision involves a complaint filed by Ronald D. White (White or “Complainant”) under the Department of Energy (DOE) Contractor Employee Protection Program, codified at 10 C.F.R. Part 708....

  1. EIS-0376: White Wind Farm Brookings County, South Dakota

    Broader source: Energy.gov [DOE]

    This EIS evaluates the potential environmental impacts of a proposal by Western to interconnect its proposed White Wind Farm Project (Project) to Western’s transmission system at the existing White...

  2. Men in question: rethinking white masculinity after the sixties 

    E-Print Network [OSTI]

    Marsh, Samantha Jane

    2013-02-22

    The social and political movements of the 1960s created a contemporary crisis in white masculinity. The civil rights, women's liberation, and counterculture movements all challenged traditional notions of white masculinity ...

  3. White light emitting diode as liquid crystal display backlight

    E-Print Network [OSTI]

    Soon, Chian Myau

    2007-01-01

    The discovery of high brightness (white) light emitting diode (LED) is considered as a real threat to the current lighting industry in various applications. One of the most promising sectors would be using white LED to ...

  4. White sponge nevus in a patient with EEC syndrome

    E-Print Network [OSTI]

    Dalben, Gisele Silva; Cursino, Helize A; Barbosa, Bruno A; Costa, Beatriz; Consolaro, Alberto

    2010-01-01

    family members affected by WSN nor by the EEC syndrome. Toand suggested the term “white sponge nevus” (WSN) [ 1 ].The WSN is one among the several white lesions of the oral

  5. MOF Coating a Promising Path to White LEDs

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

    MOF Coating a Promising Path to White LEDs MOF Coating a Promising Path to White LEDs Print Friday, 27 February 2015 17:11 Hu et al. designed a new yellow phosphor with high...

  6. Written in Black and White: Creating an Ideal America, 1919-1970

    E-Print Network [OSTI]

    Gann, Dustin Malone

    2012-05-31

    Dumenil, 202. Dumenil’s synthesis of the early twentieth century, while breaking no new theoretical ground, connects Wiebe’s notion of “island communities” and the increasing interplay of peoples to the rising clash between modernism and fundamentalism... and examines an expansive breadth of sources, her narrow geographical focus limits the applicability of her analysis. Beyond New York, and more centrally focused on race relations, Thomas Sugrue’s The Origins of the Urban Crisis, Robert Self’s American...

  7. INAA and distribution patterns of Classic Mimbres Black-on-white vessels during the Classic period 

    E-Print Network [OSTI]

    Dahlin, Eleanor Sherlock

    2003-01-01

    of the project were: (1) bowls were distributed throughout the Mimbres cultural system more often than jars; (2) vessel movement between sites within a region exceeded vessel movement between regions; (3) the Mimbres manufactured vessels at the village level; and...

  8. Of Black Sheep and White Crows: Is Bilinguals’ Memory for Figurative Meaning Language-Specific 

    E-Print Network [OSTI]

    Pritchett, Lena K

    2012-07-11

    and de Groot, 1997; see Marian, 2008, for a review of bilingual memory models). The shared system view is also known in the literature as the ?interdependence hypothesis? and the separate systems view is known as the ?independence hypothesis...

  9. Socioeconomic status in relation to early menarche among black and white girls

    E-Print Network [OSTI]

    2009-01-01

    unadjusted and adjusted for anthropometry and maternal age33]. With regard to anthropometry, recent longitudinaleducational attainment, and anthropometry. The inverse was

  10. Attributes influencing the adjustment of white faculty at selected historically black colleges and universities in Texas 

    E-Print Network [OSTI]

    Louis, Dave Anthony Robert

    2006-10-30

    research with respect to minority-classified groups at various institutions of higher education. The results may possibly add to the discourse on multiculturalism and diversity in American higher education....

  11. Health in black and white : debates on racial and ethnic health disparities in Brazil

    E-Print Network [OSTI]

    Pagano, Anna

    2011-01-01

    like Dr. Karen, that the Lula administration had implementedadministration of Luís Inácio “Lula” da Silva (2003-2010).the regime of Luís Inácio “Lula” da Silva (2003- 2010). It

  12. Health in black and white : debates on racial and ethnic health disparities in Brazil

    E-Print Network [OSTI]

    Pagano, Anna

    2011-01-01

    Maria Eliana Labra 2000 Health Sector Reform in Brazil: AInternational Journal of Health Services 30(1):129-162.Zilda Pereira da Silva 2007 Health Inequalities Based on

  13. Ed Westcott: Legacy in Black and White | Y-12 National Security Complex

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submitKansas Nuclear Profile 2010Mesoscopy andSavingYearOutreach Program EdEdEd

  14. Strong blue and white photoluminescence emission of BaZrO{sub 3} undoped and lanthanide doped phosphor for light emitting diodes application

    SciTech Connect (OSTI)

    Romero, V.H.; De la Rosa, E.; Salas, P.; Velazquez-Salazar, J.J.

    2012-12-15

    In this paper, we report the obtained strong broadband blue photoluminescence (PL) emission centered at 427 nm for undoped BaZrO{sub 3} observed after 266 nm excitation of submicron crystals prepared by hydrothermal/calcinations method. This emission is enhanced with the introduction of Tm{sup 3+} ions and is stronger than the characteristic PL blue emission of such lanthanide. The proposed mechanism of relaxation for host lattice emission is based on the presence of oxygen vacancies produced during the synthesis process and the charge compensation due to the difference in the electron valence between dopant and substituted ion in the host. Brilliant white light emission with a color coordinate of (x=0.29, y=0.32) was observed by combining the blue PL emission from the host with the green and red PL emission from Tb{sup 3+} and Eu{sup 3+} ions, respectively. The color coordinate can be tuned by changing the ratio between blue, green and red band by changing the concentration of lanthanides. - Graphical abstract: Strong blue emission from undoped BaZrO{sub 3} phosphor and white light emission by doping with Tb{sup 3+} (green) and Eu{sup 3+} (red) after 266 nm excitation. Highlights: Black-Right-Pointing-Pointer Blue emission from BaZrO{sub 3} phosphor. Black-Right-Pointing-Pointer Blue emission enhanced with Tm{sup 3+}. Black-Right-Pointing-Pointer White light from BaZrO{sup 3+} phosphor.

  15. Strings, higher curvature corrections, and black holes

    E-Print Network [OSTI]

    Thomas Mohaupt

    2005-12-05

    We review old and recent results on subleading contributions to black hole entropy in string theory.

  16. Physics: the big black box Mirror conjecture

    E-Print Network [OSTI]

    Cavalieri, Renzo

    Physics: the big black box Math Mirror conjecture A look into the mirror (I) an overview of Mirror Symmetry #12;Physics: the big black box Math Mirror conjecture Outline 1 Physics: the big black box 2 Math Symmetry #12;Physics: the big black box Math Mirror conjecture A slogan Mirror Symmetry is a correspondence

  17. White LED with High Package Extraction Efficiency

    SciTech Connect (OSTI)

    Yi Zheng; Matthew Stough

    2008-09-30

    The goal of this project is to develop a high efficiency phosphor converting (white) Light Emitting Diode (pcLED) 1-Watt package through an increase in package extraction efficiency. A transparent/translucent monolithic phosphor is proposed to replace the powdered phosphor to reduce the scattering caused by phosphor particles. Additionally, a multi-layer thin film selectively reflecting filter is proposed between blue LED die and phosphor layer to recover inward yellow emission. At the end of the project we expect to recycle approximately 50% of the unrecovered backward light in current package construction, and develop a pcLED device with 80 lm/W{sub e} using our technology improvements and commercially available chip/package source. The success of the project will benefit luminous efficacy of white LEDs by increasing package extraction efficiency. In most phosphor-converting white LEDs, the white color is obtained by combining a blue LED die (or chip) with a powdered phosphor layer. The phosphor partially absorbs the blue light from the LED die and converts it into a broad green-yellow emission. The mixture of the transmitted blue light and green-yellow light emerging gives white light. There are two major drawbacks for current pcLEDs in terms of package extraction efficiency. The first is light scattering caused by phosphor particles. When the blue photons from the chip strike the phosphor particles, some blue light will be scattered by phosphor particles. Converted yellow emission photons are also scattered. A portion of scattered light is in the backward direction toward the die. The amount of this backward light varies and depends in part on the particle size of phosphors. The other drawback is that yellow emission from phosphor powders is isotropic. Although some backward light can be recovered by the reflector in current LED packages, there is still a portion of backward light that will be absorbed inside the package and further converted to heat. Heat generated in the package may cause a deterioration of encapsulant materials, affecting the performance of both the LED die and phosphor, leading to a decrease in the luminous efficacy over lifetime. Recent studies from research groups at Rensselaer Polytechnic Institute found that, under the condition to obtain a white light, about 40% of the light is transmitted outward of the phosphor layer and 60% of the light is reflected inward.1,2 It is claimed that using scattered photon extraction (SPE) technique, luminous efficacy is increased by 60%. In this project, a transparent/translucent monolithic phosphor was used to replace the powdered phosphor layer. In the normal pcLED package, the powdered phosphor is mixed with silicone either to be deposited on the top of LED die forming a chip level conversion (CLC) white LED or to be casted in the package forming a volume conversion white LED. In the monolithic phosphors there are no phosphor powder/silicone interfaces so it can reduce the light scattering caused by phosphor particles. Additionally, a multi-layer thin film selectively reflecting filter is inserted in the white LED package between the blue LED die and phosphor layer. It will selectively transmit the blue light from the LED die and reflect the phosphor's yellow inward emission outward. The two technologies try to recover backward light to the outward direction in the pcLED package thereby improving the package extraction efficiency.

  18. LIMB-DARKENING COEFFICIENTS FOR ECLIPSING WHITE DWARFS

    SciTech Connect (OSTI)

    Gianninas, A.; Strickland, B. D.; Kilic, Mukremin [Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, 440 W. Brooks St., Norman, OK 73019 (United States)] [Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, 440 W. Brooks St., Norman, OK 73019 (United States); Bergeron, P., E-mail: alexg@nhn.ou.edu, E-mail: benstrickland@ou.edu, E-mail: kilic@ou.edu, E-mail: bergeron@astro.umontreal.ca [Departement de Physique, Universite de Montreal, C.P. 6128, Succ. Centre-Ville, Montreal, Quebec H3C 3J7 (Canada)

    2013-03-20

    We present extensive calculations of linear and nonlinear limb-darkening coefficients as well as complete intensity profiles appropriate for modeling the light-curves of eclipsing white dwarfs. We compute limb-darkening coefficients in the Johnson-Kron-Cousins UBVRI photometric system as well as the Large Synoptic Survey Telescope (LSST) ugrizy system using the most up to date model atmospheres available. In all, we provide the coefficients for seven different limb-darkening laws. We describe the variations of these coefficients as a function of the atmospheric parameters, including the effects of convection at low effective temperatures. Finally, we discuss the importance of having readily available limb-darkening coefficients in the context of present and future photometric surveys like the LSST, Palomar Transient Factory, and the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS). The LSST, for example, may find {approx}10{sup 5} eclipsing white dwarfs. The limb-darkening calculations presented here will be an essential part of the detailed analysis of all of these systems.

  19. Black hole horizons Eric Gourgoulhon

    E-Print Network [OSTI]

    Gourgoulhon, Eric

    on a black hole: up to 42% of the mass-energy mc2 of accreted matter ! NB: thermonuclear reactions release: a very deep gravitational potential well Release of potential gravitational energy by accretion

  20. Thermodynamics of regular black hole

    E-Print Network [OSTI]

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

    2008-09-21

    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.

  1. Black Holes and Nuclear Dynamics

    E-Print Network [OSTI]

    David Merritt

    2006-02-17

    Supermassive black holes inhabit galactic nuclei, and their presence influences in crucial ways the evolution of the stellar distribution. The low-density cores observed in bright galaxies are probably a result of black hole infall, while steep density cusps like those at the Galactic center are a result of energy exchange between stars moving in the gravitational field of the single black hole. Loss-cone dynamics are substantially more complex in galactic nuclei than in collisionally-relaxed systems like globular clusters due to the wider variety of possible geometries and orbital populations. The rate of star-black hole interactions has begun to be constrained through observations of energetic events associated with stellar tidal disruptions.

  2. Causality and black holes in spacetimes with a preferred foliation

    E-Print Network [OSTI]

    Bhattacharyya, Jishnu; Sotiriou, Thomas P

    2015-01-01

    We develop a framework that facilitates the study of the causal structure of spacetimes with a causally preferred foliation. Such spacetimes may arise as solutions of Lorentz-violating theories, e.g. Horava gravity. Our framework allows us to rigorously define concepts such as black/white holes and to formalize the notion of a `universal horizon', that has been previously introduced in the simpler setting of static and spherically symmetric geometries. We also touch upon the issue of development and prove that universal horizons are Cauchy horizons when evolution depends on boundary data or asymptotic conditions. We establish a local characterisation of universal horizons in stationary configurations. Finally, under the additional assumption of axisymmetry, we examine under which conditions these horizons are cloaked by Killing horizons, which can act like usual event horizons for low-energy excitations.

  3. Black Boundary Lines: Race, Class and Gender among Black Undergraduate Students

    E-Print Network [OSTI]

    Morales, Erica

    2012-01-01

    C. 1994. Behind the Mule: Race and Class in African AmericanHarlemworld: Doing Race and Class in Contemporary BlackBlue-Chip Black: Race, Class and Status in the New Black

  4. Accretion Processes On a Black Hole

    E-Print Network [OSTI]

    Sandip K. Chakrabarti

    1996-05-03

    We describe astrophysical processes around a black hole keeping primarily the physics of accretion in mind. In Section 1, we briefly discuss the formation, evolution and detection of black holes. We also discuss the difference of flow properties around a black hole and a Newtonian star. In Section 2, we present past and present developments in the study of spherically accreting flows. We study the properties of Bondi flow with and without radiative transfer. In the presence of significant angular momentum, which is especially true in a binary system, matter will be accreted as a thin Keplerian disk. In Section 3, we discuss a large number of models of these disks including the more popular standard disk model. We present magnetized disk models as well. Since the angular momentum is high in these systems, rotational motion is the most dominant component compared to the radial or the vertical velocity components. In Section 4, we study thick disk models which are of low angular momentum but still have no significant radial motion. The accretion rates could be very high causing the flow to become radiation dominated and the disk to be geometrically thick. For low accretion rates, ion pressure supported disks are formed. In Section 5, we extensively discuss the properties of transonic flows which has with sub-Keplerian angular momentum. In the absence of shock discontinuities, these sub-Keplerian flows are basically advecting, similar to Bondi flows, close to the black holes, though far away they match Keplerian or sub-Keplerian disks. In presence of shocks, the post-shock flow becomes rotation dominated similar to thick disks. In Section 6, we present results of important numerical simulations of accretion flows. Significant results from the studies of evolution of viscous transonic flows are reported. In Section 7, we discuss some observational evidences of the black hole accretion. We also present a detailed model of a generalized accretion disk and present its spectra and compare with observations. In Section 8, we summarize the review and make concluding remarks.

  5. The hydraulic jump as a white hole

    E-Print Network [OSTI]

    G. E. Volovik

    2005-10-21

    In the geometry of the circular hydraulic jump, the velocity of the liquid in the interior region exceeds the speed of capillary-gravity waves (ripplons), whose spectrum is `relativistic' in the shallow water limit. The velocity flow is radial and outward, and thus the relativistic ripplons cannot propagating into the interior region. In terms of the effective 2+1 dimensional Painleve-Gullstrand metric appropriate for the propagating ripplons, the interior region imitates the white hole. The hydraulic jump represents the physical singularity at the white-hole horizon. The instability of the vacuum in the ergoregion inside the circular hydraulic jump and its observation in recent experiments on superfluid 4He by E. Rolley, C. Guthmann, M.S. Pettersen and C. Chevallier in physics/0508200 are discussed.

  6. The hydraulic jump as a white whole

    E-Print Network [OSTI]

    Volovik, G E

    2005-01-01

    In the geometry of the circular hydraulic jump, the velocity of the liquid in the interior region exceeds the speed of capillary-gravity waves (ripplons), whose spectrum is `relativistic' in the shallow water limit. The velocity flow is radial and outward, and thus the relativistic ripplons cannot propagating into the interior region. In terms of the effective 2+1 dimensional Painleve-Gullstrand metric appropriate for the propagating ripplons, the interior region imitates the `white-hole'. The hydraulic jump represents the physical singularity at the white-hole horizon. The instability of the vacuum in the ergoregion inside the circular hydraulic jump and its observation in recent experiments on superfluid 4He by E. Rolley, C. Guthmann, M.S. Pettersen and C. Chevallier in physics/0508200 are discussed.

  7. Collapse models with non-white noises

    E-Print Network [OSTI]

    Stephen L. Adler; Angelo Bassi

    2008-02-01

    We set up a general formalism for models of spontaneous wave function collapse with dynamics represented by a stochastic differential equation driven by general Gaussian noises, not necessarily white in time. In particular, we show that the non-Schrodinger terms of the equation induce the collapse of the wave function to one of the common eigenstates of the collapsing operators, and that the collapse occurs with the correct quantum probabilities. We also develop a perturbation expansion of the solution of the equation with respect to the parameter which sets the strength of the collapse process; such an approximation allows one to compute the leading order terms for the deviations of the predictions of collapse models with respect to those of standard quantum mechanics. This analysis shows that to leading order, the ``imaginary'' noise trick can be used for non-white Gaussian noise.

  8. Constraining Black Hole Spin Via X-ray Spectroscopy

    E-Print Network [OSTI]

    Laura W. Brenneman; Christopher S. Reynolds

    2006-08-23

    We present an analysis of the observed broad iron line feature and putative warm absorber in the long 2001 XMM-Newton observation of the Seyfert-1.2 galaxy MCG-6-30-15. The new "kerrdisk" model we have designed for simulating line emission from accretion disk systems allows black hole spin to be a free parameter in the fit, enabling the user to formally constrain the angular momentum of a black hole, among other physical parameters of the system. In an important extension of previous work, we derive constraints on the black hole spin in MCG-6-30-15 using a self-consistent model for X-ray reflection from the surface of the accretion disk while simultaneously accounting for absorption by dusty photoionized material along the line of sight (the warm absorber). Even including these complications, the XMM-Newton/EPIC-pn data require extreme relativistic broadening of the X-ray reflection spectrum; assuming no emission from within the radius of marginal stability, we derive a formal constraint on the dimensionless black hole spin parameter of a > 0.987 at 90% confidence. The principal unmodeled effect that can significantly reduce the inferred black hole spin is powerful emission from within the radius of marginal stability. Although significant theoretical developments are required to fully understand this region, we argue that the need for a rapidly spinning black hole is robust to physically plausible levels of emission from within the radius of marginal stability. In particular, we show that a non-rotating black hole is strongly ruled out.

  9. Fishing in Black Holes

    E-Print Network [OSTI]

    A. Brotas

    2006-09-01

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

  10. Whites Renewable Energy | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page| Open Energy Information Serbia-EnhancingEtGeorgia: EnergyMaryland:Meadow Lake, New Jersey:Whitefish,Whitehouse,Whites

  11. Composition of White Lead and Paints. 

    E-Print Network [OSTI]

    Fraps, G. S. (George Stronach)

    1908-01-01

    EXPERIMENT 8TATIONS. BULLETIN NO. 114 NOVEMBER, 1908. Composition of White lead and Paints. G. S. FRAPS, PH. D,, Chemist. POSTOFFICE : COLLEGE STATION, BRAZOS COUNTY, TEXAS. AUSTIY, TEXAS: VON BOECKMANN-JONES COMPANY, PRINTERS TEXAS AGRICULTURAL EXPE...\\gricultural a M'echanicnl College, in Brazos connty. The posfofEw :>rltlrris iq College SCati Texas. Reports and bulletins are sent free upon application to the Director. TABLE OF CONTENTS . Paint Materials...

  12. HTGR Mechanistic Source Terms White Paper

    SciTech Connect (OSTI)

    Wayne Moe

    2010-07-01

    The primary purposes of this white paper are: (1) to describe the proposed approach for developing event specific mechanistic source terms for HTGR design and licensing, (2) to describe the technology development programs required to validate the design methods used to predict these mechanistic source terms and (3) to obtain agreement from the NRC that, subject to appropriate validation through the technology development program, the approach for developing event specific mechanistic source terms is acceptable

  13. Low Voltage White Phosphorescent OLED Achievements

    Broader source: Energy.gov [DOE]

    Universal Display Corporation (UDC) and its research partners at Princeton University and the University of Southern California have succeeded in developing a white phosphorescent OLED (PHOLED™) that achieved a record efficiency of 20 lumens per watt. This achievement is the result of the team's collaborative efforts to increase the efficiency of PHOLED lighting by focusing on two critical factors: lowering the drive voltages and increasing the amount of light extracted.

  14. White Earth Biomass/Biogas Feasibility Study

    SciTech Connect (OSTI)

    Triplett, Michael

    2015-03-12

    The White Earth Nation examined the feasibility of cost savings and fossil energy reduction through the installation of biogas/biomass boiler at the tribal casino. The study rejected biogas options due to availability and site constraints, but found a favorable environment for technical and financial feasibility of installing a 5 MMBtu hot water boiler system to offset 60-70 percent of current fuel oil and propane usage.

  15. Extremal Limits of Rotating Black Holes

    E-Print Network [OSTI]

    Laura Andrianopoli; Riccardo D'Auria; Antonio Gallerati; Mario Trigiante

    2013-05-30

    We consider non-extremal, stationary, axion-dilaton solutions to ungauged symmetric supergravity models, obtained by Harrison transformations of the non-extremal Kerr solution. We define a general algebraic procedure, which can be viewed as an Inonu-Wigner contraction of the Noether charge matrix associated with the effective D=3 sigma-model description of the solution, yielding, through different singular limits, the known BPS and non-BPS extremal black holes (which include the under-rotating non-BPS one). The non-extremal black hole can thus be thought of as "interpolating" among these limit-solutions. The algebraic procedure that we define generalizes the known Rasheed-Larsen limit which yielded, in the Kaluza-Klein theory, the first instance of under-rotating extremal solution. As an example of our general result, we discuss in detail the non-extremal solution in the T^3-model, with either (q_0, p^1) or (p^0, q_1) charges switched on, and its singular limits. Such solutions, computed in D=3 through the solution-generating technique, is completely described in terms of D=4 fields, which include the fully integrated vector fields.

  16. Aspects of Accretion Processes On a Rotating Black Hole

    E-Print Network [OSTI]

    Sandip K. Chakrabarti

    1996-11-10

    We describe the most general nature of accretion and wind flows around a compact object and emphasize on the properties which are special to black hole accretion. The angular momentum distribution in the most general solution is far from Keplerian, and the non-Keplerian disks can include standing shock waves. We also present fully time dependent numerical simulation results to show that they agree with these analytical solutions. We describe the spectral properties of these accretion disks and show that the soft and hard states of the black hole candidates could be explained by the change of the accretion rate of the disk. We present fits of the observational data to demonstrate the presence of sub-Keplerian flows around black holes.

  17. Satellite observations of thought experiments close to a black hole

    E-Print Network [OSTI]

    S. K. Chakrabarti

    2000-07-18

    Since black holes are `black', methods of their identification must necessarily be indirect. Due to very special boundary condition on the horizon, the advective flow behaves in a particular way, which includes formation of centrifugal pressure dominated boundary layer or CENBOL where much of the infall energy is released and outflows are generated. The observational aspects of black holes must depend on the steady and time-dependent properties of this boundary layer. Several observational results are written down in this review which seem to support the predictions of thought experiments based on this advective accretion/outflow model. In future, when gravitational waves are detected, some other predictions of this model could be tested as well.

  18. Simulation of the White Dwarf -- White Dwarf galactic background in the LISA data

    E-Print Network [OSTI]

    Jeffrey A. Edlund; Massimo Tinto; Andrzej Królak; Gijs Nelemans

    2005-04-07

    LISA (Laser Interferometer Space Antenna) is a proposed space mission, which will use coherent laser beams exchanged between three remote spacecraft to detect and study low-frequency cosmic gravitational radiation. In the low-part of its frequency band, the LISA strain sensitivity will be dominated by the incoherent superposition of hundreds of millions of gravitational wave signals radiated by inspiraling white-dwarf binaries present in our own galaxy. In order to estimate the magnitude of the LISA response to this background, we have simulated a synthesized population that recently appeared in the literature. We find the amplitude of the galactic white-dwarf binary background in the LISA data to be modulated in time, reaching a minimum equal to about twice that of the LISA noise for a period of about two months around the time when the Sun-LISA direction is roughly oriented towards the Autumn equinox. Since the galactic white-dwarfs background will be observed by LISA not as a stationary but rather as a cyclostationary random process with a period of one year, we summarize the theory of cyclostationary random processes and present the corresponding generalized spectral method needed to characterize such process. We find that, by measuring the generalized spectral components of the white-dwarf background, LISA will be able to infer properties of the distribution of the white-dwarfs binary systems present in our Galaxy.

  19. The White Dwarf -- White Dwarf galactic background in the LISA data

    E-Print Network [OSTI]

    Jeffrey A. Edlund; Massimo Tinto; Andrzej Krolak; Gijs Nelemans

    2005-04-22

    LISA (Laser Interferometer Space Antenna) is a proposed space mission, which will use coherent laser beams exchanged between three remote spacecraft to detect and study low-frequency cosmic gravitational radiation. In the low-part of its frequency band, the LISA strain sensitivity will be dominated by the incoherent superposition of hundreds of millions of gravitational wave signals radiated by inspiraling white-dwarf binaries present in our own galaxy. In order to estimate the magnitude of the LISA response to this background, we have simulated a synthesized population that recently appeared in the literature. We find the amplitude of the galactic white-dwarf binary background in the LISA data to be modulated in time, reaching a minimum equal to about twice that of the LISA noise for a period of about two months around the time when the Sun-LISA direction is roughly oriented towards the Autumn equinox. Since the galactic white-dwarfs background will be observed by LISA not as a stationary but rather as a cyclostationary random process with a period of one year, we summarize the theory of cyclostationary random processes, present the corresponding generalized spectral method needed to characterize such process, and make a comparison between our analytic results and those obtained by applying our method to the simulated data. We find that, by measuring the generalized spectral components of the white-dwarf background, LISA will be able to infer properties of the distribution of the white-dwarfs binary systems present in our Galaxy.

  20. Can reducing black carbon emissions counteract global warming?

    SciTech Connect (OSTI)

    Tami C. Bond; Haolin Sun

    2005-08-15

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

  1. The mass function of high redshift seed black holes

    E-Print Network [OSTI]

    Lodato, G; Lodato, Giuseppe; Natarajan, Priyamvada

    2007-01-01

    In this paper we derive the mass function of seed black holes that result from the central mass concentrated via disc accretion in collapsed haloes at redshift $z\\approx 15$. Using standard arguments including stability, we show that these pre-galactic discs can assemble a significant mass concentration in the inner regions, providing fuel for the formation and initial growth of super-massive black holes. Assuming that these mass concentrations do result in central seed black holes, we determine the mass distribution of these seeds as a function of key halo properties. The seed mass distribution determined here turns out to be asymmetric and skewed to higher masses. Starting with these initial seeds, building up to $10^9$ solar masses by $z = 6$ to power the bright quasars is not a problem in the standard LCDM cosmogony. These seed black holes in gas rich environments are likely to grow into the supermassive black holes at later times via mergers and accretion. Gas accretion onto these seeds at high redshift ...

  2. White Oak Creek Watershed topographic map and related materials

    SciTech Connect (OSTI)

    Farrow, N.D.

    1981-04-01

    On March 22, 1978 a contract was let to Accu-Air Surveys, Inc., of Seymour, Indiana, to produce a topographic map of the White Oak Creek Watershed. Working from photography and ground control surveys, Accu-Air produced a map to ORNL's specifications. The map is in four sections (N.W., N.E., S.W., S.E.) at a scale of 1:2400. Contour intervals are 5 ft (1.5 m) with accented delineations every 25 ft (7.6 m). The scribe method was used for the finished map. Planimetric features, roads, major fence lines, drainage features, and tree lines are included. The ORNL grid is the primary coordinate system which is superimposed on the state plain coordinates.

  3. An Intermediate-Mass Black Hole Candidate in M51?

    E-Print Network [OSTI]

    Earnshaw, H M

    2015-01-01

    We present the current results of an investigation into M51 ULX-7, using archival data from XMM-Newton, Chandra and NuSTAR, and optical and radio data from HST and VLA. The source has a consistently hard power-law X-ray spectrum and high short-term variability. This is unusual variability behaviour for a ULX, as we would expect highly variable ULXs to have soft energy spectra. The power spectrum features a break at ~1e-3 Hz, from low frequency spectral index alpha=0.1 to high frequency spectral index alpha=0.8, analogous to the low frequency break found in power spectra of black holes accreting in the low/hard state. We do not observe a corresponding high frequency break, however taking the white noise level as a frequency lower limit of the break, we can calculate a black hole mass upper limit of 9.12e4 solar masses, assuming that the ULX is in the low/hard state. While there is no radio detection, we find a flux density upper limit of 87 micro-Jy/beam. Using the X-ray/radio fundamental plane, we calculate a...

  4. Black hole mimickers: Regular versus singular behavior

    SciTech Connect (OSTI)

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

    2008-07-15

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

  5. International black tea market integration and price discovery 

    E-Print Network [OSTI]

    Dharmasena, Kalu Arachchillage Senarath Dhananjaya Bandara

    2004-09-30

    In this thesis we study three basic issues related to international black tea markets: Are black tea markets integrated? Where is the price of black tea discovered? Are there leaders and followers in black tea markets? We ...

  6. Energy on black hole spacetimes

    E-Print Network [OSTI]

    Alejandro Corichi

    2012-07-18

    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.

  7. Heat Engine of black holes

    E-Print Network [OSTI]

    J. Sadeghi; Kh. Jafarzade

    2015-06-23

    As we know, the cosmological constant in different theories of gravity acts as a thermodynamics variable. The cosmological constant exists in different actions of gravity and also appears in the solution of such theories. These lead to use the black hole as a heat engines. Also, there are two values for the cosmological constant as positive and negative values. The case of negative cosmological constant supplies a natural realization of these engines in terms of the field theory description of the fluids to which they are holographically dual. In this paper, we are going to define heat engines for two different black holes as Dyonic BH and Kerr BH. And also, we calculate maximum efficiency for two black holes.

  8. Charged rotating dilaton black strings

    SciTech Connect (OSTI)

    Dehghani, M.H.; Farhangkhah, N.

    2005-02-15

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

  9. Quantum Criticality and Black Holes

    ScienceCinema (OSTI)

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

    2009-09-01

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

  10. Optical Identification of He White Dwarfs Orbiting Four Millisecond Pulsars in the Globular Cluster 47 Tucanae

    E-Print Network [OSTI]

    Cadelano, M; Ferraro, F R; Salaris, M; Dalessandro, E; Lanzoni, B; Freire, P C C

    2015-01-01

    We used ultra-deep UV observations obtained with the Hubble Space Telescope to search for optical companions to binary millisecond pulsars (MSPs) in the globular cluster 47 Tucanae. We identified four new counterparts (to MSPs 47TucQ, 47TucS, 47TucT and 47TucY) and confirmed those already known (to MSPs 47TucU and 47TucW). In the color magnitude diagram, the detected companions are located in a region between the main sequence and the CO white dwarf cooling sequences, consistent with the cooling tracks of He white dwarfs of mass between 0.15 Msun and 0.20 Msun. For each identified companion, mass, cooling age, temperature and pulsar mass (as a function of the inclination angle) have been derived and discussed. For 47TucU we also found that the past accretion history likely proceeded in a sub-Eddington rate. The companion to the redback 47TucW is confirmed to be a non degenerate star, with properties particularly similar to those observed for black widow systems. Two stars have been identified within the 2-sig...

  11. Black Holes and Galaxy Dynamics

    E-Print Network [OSTI]

    David Merritt

    1999-06-02

    The consequences of nuclear black holes for the structure and dynamics of stellar spheroids are reviewed. Slow growth of a black hole in a pre-existing core produces a steep power-law density profile similar to the cusps seen in faint elliptical galaxies. The weaker cusps in bright ellipticals may result from ejection of stars by a coalescing black-hole binary; there is marginal kinematical evidence for such a process having occurred in M87. Stellar orbits in a triaxial nucleus are mostly regular at radii where the gravitational force is dominated by the black hole; however the orbital shapes are not conducive to reinforcing the triaxial figure, hence nuclei are likely to be approximately axisymmetric. In triaxial potentials, a ``zone of chaos'' extends outward to a radius where the enclosed stellar mass is roughly 100 times the mass of the black hole; in this chaotic zone, no regular, box-like orbits exist. At larger radii, the phase space in triaxial potentials is complex, consisting of stochastic orbits as well as regular orbits associated with stable resonances. Figure rotation tends to increase the degree of stochasticity. Both test-particle integrations and N-body simulations suggest that a triaxial galaxy responds globally to the presence of a central mass concentration by evolving toward more axisymmetric shapes; the evolution occurs rapidly when the mass of the central object exceeds roughly 2% of the mass in stars. The lack of significant triaxiality in most early-type galaxies may be a consequence of orbital evolution induced by nuclear black holes.

  12. Radiation transport around Kerr black holes

    E-Print Network [OSTI]

    Schnittman, Jeremy David

    2005-01-01

    This Thesis describes the basic framework of a relativistic ray-tracing code for analyzing accretion processes around Kerr black holes. We begin in Chapter 1 with a brief historical summary of the major advances in black ...

  13. Does phantom energy produce black hole?

    E-Print Network [OSTI]

    F. Rahaman; A. Ghosh; M. Kalam

    2006-12-23

    We have found an exact solution of spherically symmetrical Einstein equations describing a black hole with a special type phantom energy source. It is surprising to note that our solution is analogous to Reissner-Nordstr\\"{o}m black hole.

  14. Introduction to Black Hole Evaporation

    E-Print Network [OSTI]

    Pierre-Henry Lambert

    2014-01-16

    These lecture notes are an elementary and pedagogical introduction to the black hole evaporation, based on a lecture given by the author at the Ninth Modave Summer School in Mathematical Physics and are intended for PhD students. First, quantum field theory in curved spacetime is studied and tools needed for the remaining of the course are introduced. Then, quantum field theory in Rindler spacetime in 1+1 dimensions and in the spacetime of a spherically collapsing star are considered, leading to Unruh and Hawking effects, respectively. Finally, some consequences such as thermodynamics of black holes and information loss paradox are discussed.

  15. 4d neutral dilatonic black holes and (4+p) dimensional nondilatonic black p-branes

    E-Print Network [OSTI]

    J. R. Morris

    2000-01-11

    It is shown that, in contrast to the case of extreme 4d dilatonic black holes, 4d neutral dilatonic black holes with horizon singularities can not be interpreted as nonsingular nondilatonic black p-branes in (4+p) dimensions, regardless of the number of extra dimensions p. That is, extra dimensions do not remove naked singularities of 4d neutral dilatonic black holes.

  16. White Mountains Geothermal Area | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page| Open Energy Information Serbia-EnhancingEtGeorgia: EnergyMaryland:Meadow Lake, New Jersey: Energy Resources JumpWhite

  17. Whiting, Vermont: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page| Open Energy Information Serbia-EnhancingEtGeorgia: EnergyMaryland:Meadow Lake, NewWhiteside County,County,Whiting,

  18. Sandia Energy - White Light Creation Architectures

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory ofDid youOxygenLaboratory FellowsStationarytdheinrWaterWavelengthWhite

  19. THE WHITE HOUSE | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:Financing ToolInternational Affairs, Before theFebruary 1,7/109TESLA TESLA TESLATHE WHITE HOUSE THE

  20. White Mountains Geothermal Area | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION JEnvironmental Jump to:EA EISTJThinWarsaw,What Is a Small Community WindWhere is DBWindWhite

  1. White Energy Ltd | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop IncIowa (Utility Company)Idaho)VosslohWest PlainsAssn, Inc Jump to:WhiskeyWhite

  2. Women @ Energy: Karen White | Department of Energy

    Office of Environmental Management (EM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirley Ann Jackson About1996HowFOAShowingFuelWeatherize »Eve Kovacs Women @Jill Deem WomenWhite

  3. AdS and Lifshitz Black Holes in Conformal and Einstein-Weyl Gravities

    E-Print Network [OSTI]

    H. Lu; Y. Pang; C. N. Pope; J. Vazquez-Poritz

    2012-04-14

    We study black hole solutions in extended gravities with higher-order curvature terms, including conformal and Einstein-Weyl gravities. In addition to the usual AdS vacuum, the theories admit Lifshitz and Schr\\"odinger vacua. The AdS black hole in conformal gravity contains an additional parameter over and above the mass, which may be interpreted as a massive spin-2 hair. By considering the first law of thermodynamics, we find that it is necessary to introduce an associated additional intensive/extensive pair of thermodynamic quantities. We also obtain new Liftshitz black holes in conformal gravity and study their thermodynamics. We use a numerical approach to demonstrate that AdS black holes beyond the Schwarzschild-AdS solution exist in Einstein-Weyl gravity. We also demonstrate the existence of asymptotically Lifshitz black holes in Einstein-Weyl gravity. The Lifshitz black holes arise at the boundary of the parameter ranges for the AdS black holes. Outside the range, the solutions develop naked singularities. The asymptotically AdS and Lifshitz black holes provide an interesting phase transition, in the corresponding boundary field theory, from a relativistic Lorentzian system to a non-relativistic Lifshitz system.

  4. Classical and thermodynamic stability of black holes

    E-Print Network [OSTI]

    Ricardo Monteiro

    2010-06-28

    We consider the stability of black holes within both classical general relativity and the semiclassical thermodynamic description. In particular, we study linearised perturbations and their contribution to the gravitational partition function, addressing technical issues for charged (Reissner-Nordstrom) and rotating (Kerr-AdS) black holes. Exploring the connection between classical and thermodynamic stability, we find classical instabilities of Myers-Perry black holes and bifurcations to new black hole families.

  5. Will black holes eventually engulf the universe?

    E-Print Network [OSTI]

    Prado Martin-Moruno; Jose A. Jimenez Madrid; Pedro F. Gonzalez-Diaz

    2006-03-28

    The Babichev-Dokuchaev-Eroshenko model for the accretion of dark energy onto black holes has been extended to deal with black holes with non-static metrics. The possibility that for an asymptotic observer a black hole with large mass will rapidly increase and eventually engulf the Universe at a finite time in the future has been studied by using reasonable values for astronomical parameters. It is concluded that such a phenomenon is forbidden for all black holes in quintessential cosmological models.

  6. Hawking Emission and Black Hole Thermodynamics

    E-Print Network [OSTI]

    Don N. Page

    2006-12-18

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

  7. New Efficiency Record Achieved for White OLED Device

    Broader source: Energy.gov [DOE]

    Osram Opto-Semiconductors, Inc. has successfully demonstrated a white organic light emitting diode (OLED) with a record efficiency of 25 lumens per watt, the highest known efficiency achieved to date for a polymer-based white OLED. The 25 LPW cool-white-emitting device was produced by applying a standard external inorganic phosphor to Osram's record-breaking blue-emitting phosphorescent polymer device with a peak luminous efficacy of 14 LPW.

  8. BLACK HOLE FORAGING: FEEDBACK DRIVES FEEDING

    SciTech Connect (OSTI)

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

    2013-11-10

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

  9. INSTRUMENTATION, INCLUDING NUCLEAR AND PARTICLE DETECTORS; RADIATION

    Office of Scientific and Technical Information (OSTI)

    interval technical basis document Chiaro, P.J. Jr. 44 INSTRUMENTATION, INCLUDING NUCLEAR AND PARTICLE DETECTORS; RADIATION DETECTORS; RADIATION MONITORS; DOSEMETERS;...

  10. Scattering by regular black holes: Planar massless scalar waves impinging upon a Bardeen black hole

    E-Print Network [OSTI]

    Macedo, Caio F B; Crispino, Luís C B

    2015-01-01

    Singularities are common features of general relativity black holes. However, within general relativity, one can construct black holes that present no singularities. These regular black hole solutions can be achieved by, for instance, relaxing one of the energy conditions on the stress energy tensor sourcing the black hole. Some regular black hole solutions were found in the context of non-linear electrodynamics, the Bardeen black hole being the first one proposed. In this paper, we consider a planar massless scalar wave scattered by a Bardeen black hole. We compare the scattering cross section computed using a partial-wave description with the classical geodesic scattering of a stream of null geodesics, as well as with the semi-classical glory approximation. We obtain that, for some values of the corresponding black hole charge, the scattering cross section of a Bardeen black hole has a similar interference pattern of a Reissner-Nordstr\\"om black hole.

  11. Scattering by regular black holes: Planar massless scalar waves impinging upon a Bardeen black hole

    E-Print Network [OSTI]

    Caio F. B. Macedo; Ednilton S. de Oliveira; Luís C. B. Crispino

    2015-06-26

    Singularities are common features of general relativity black holes. However, within general relativity, one can construct black holes that present no singularities. These regular black hole solutions can be achieved by, for instance, relaxing one of the energy conditions on the stress energy tensor sourcing the black hole. Some regular black hole solutions were found in the context of non-linear electrodynamics, the Bardeen black hole being the first one proposed. In this paper, we consider a planar massless scalar wave scattered by a Bardeen black hole. We compare the scattering cross section computed using a partial-wave description with the classical geodesic scattering of a stream of null geodesics, as well as with the semi-classical glory approximation. We obtain that, for some values of the corresponding black hole charge, the scattering cross section of a Bardeen black hole has a similar interference pattern of a Reissner-Nordstr\\"om black hole.

  12. New approaches to black holes Eric Gourgoulhon

    E-Print Network [OSTI]

    Gourgoulhon, Eric

    References Eric Gourgoulhon (LUTH) New approaches to black holes Okinawa Nat. Col. Tech., 17 Aug 2008 2 / 36 Gourgoulhon (LUTH) New approaches to black holes Okinawa Nat. Col. Tech., 17 Aug 2008 3 / 36 #12;Local (2006)] Eric Gourgoulhon (LUTH) New approaches to black holes Okinawa Nat. Col. Tech., 17 Aug 2008 4

  13. 2012 White Book, Pacific Northwest Loads and Resources Study

    SciTech Connect (OSTI)

    2013-06-06

    The White Book is a planning analysis produced by BPA that informs BPA of its load and resource conditions for sales and purchases. The White Book provides a 10-year look at the expected obligations and resources in the Federal system and PNW region. The White Book is used as a planning tool for the Columbia River Treaty (Treaty) studies, as an information tool for customers and regional interests, and as a publication of information utilized by other planning entities for their analyses. The White Book is not used to guide day-to-day operations of the Federal Columbia River Power System (FCRPS) or determine BPA revenues or rates.

  14. 21st Century Truck Partnership - Roadmap and Technical White...

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

    21st Century Truck Partnership - Roadmap and Technical White Papers Appendix of Supporting Information - 21CTP-0003, December 2006 21st Century Truck Partnership - Roadmap and...

  15. NREL: Technology Transfer - NREL to Play Pivotal Role in White...

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

    White House Initiative to Bolster America's Manufacturing Future A photo of a large scale wind turbine with foothills in the background. Experts at the National Wind Technology...

  16. White House Solar Champions of Change - Watch Now | Department...

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

    White House Champions of Change Recognizes Solar Innovator SunShot Grand Challenge Summit Opening Session Energy Department Announces New Prize Challenge to Drive Down Solar Costs...

  17. White House Council of Economic Advisers and Energy Department...

    Energy Savers [EERE]

    of Economic Advisers and Energy Department Release New Report on Resiliency of Electric Grid During Natural Disasters White House Council of Economic Advisers and Energy Department...

  18. White River Valley Electric Cooperative- Energy Efficiency Rebate Program

    Broader source: Energy.gov [DOE]

    The residential and commercial appliance and heating rebate program encourages members to purchase Energy Star equipment that qualifies under the White River energy efficiency program. Items...

  19. White House Launches the Generation Indigenous Native Youth Challenge...

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

    the White House Domestic Policy Council Cecilia Muoz announced the launch of the Generation Indigenous Native Youth Challenge at the 2015 United National Indian Tribal Youth...

  20. EISPC White Paper on "State Approaches to Retention of Nuclear...

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

    (EISPC) has released a white paper on "State Approaches to Retention of Nuclear Power Plants" that examines operational, economic, and policy pressure points affecting...

  1. Food and Drug Administration White Oak Campus Environmental Stewardshi...

    Energy Savers [EERE]

    Stewardship and Cost Savings FEMP ESPC Success Story on water conservation and green energy at the Food and Drug Administration (FDA) White Oak Campus. PDF icon...

  2. Novel Materials for HIgh Efficiency White Phosphorescent OLED

    SciTech Connect (OSTI)

    Mark Thompson

    2008-03-31

    Our program was a materials intensive one, based on preparing new materials for phosphorescent based white organic LEDs (WOLEDs). Each of the principal projects are summarized.

  3. Assessment of the SRI Gasification Process for Syngas Generation with HTGR Integration -- White Paper

    SciTech Connect (OSTI)

    A.M. Gandrik

    2012-04-01

    This white paper is intended to compare the technical and economic feasibility of syngas generation using the SRI gasification process coupled to several high-temperature gas-cooled reactors (HTGRs) with more traditional HTGR-integrated syngas generation techniques, including: (1) Gasification with high-temperature steam electrolysis (HTSE); (2) Steam methane reforming (SMR); and (3) Gasification with SMR with and without CO2 sequestration.

  4. White-dwarf-white-dwarf galactic background in the LISA data

    SciTech Connect (OSTI)

    Edlund, Jeffrey A.; Tinto, Massimo; Krolak, Andrzej; Nelemans, Gijs [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109 (United States); Max-Planck-Institute for Gravitational Physics, Albert Einstein Institute, D-14476 Golm (Germany); Department of Astrophysics, IMAPP, Radboud University Nijmegen (Netherlands)

    2005-06-15

    LISA (Laser Interferometer Space Antenna) is a proposed space mission, which will use coherent laser beams exchanged between three remote spacecraft to detect and study low-frequency cosmic gravitational radiation. In the low part of its frequency band, the LISA strain sensitivity will be dominated by the incoherent superposition of hundreds of millions of gravitational wave signals radiated by inspiraling white-dwarf binaries present in our own Galaxy. In order to estimate the magnitude of the LISA response to this background, we have simulated a synthesized population that recently appeared in the literature. Our approach relies on entirely analytic expressions of the LISA time-delay interferometric responses to the gravitational radiation emitted by such systems, which allows us to implement a computationally efficient and accurate simulation of the background in the LISA data. We find the amplitude of the galactic white-dwarf binary background in the LISA data to be modulated in time, reaching a minimum equal to about twice that of the LISA noise for a period of about two months around the time when the Sun-LISA direction is roughly oriented towards the Autumn equinox. This suggests that, during this time period, LISA could search for other gravitational wave signals incoming from directions that are away from the galactic plane. Since the galactic white-dwarf background will be observed by LISA not as a stationary but rather as a cyclostationary random process with a period of 1 yr, we summarize the theory of cyclostationary random processes, present the corresponding generalized spectral method needed to characterize such process, and make a comparison between our analytic results and those obtained by applying our method to the simulated data. We find that, by measuring the generalized spectral components of the white-dwarf background, LISA will be able to infer properties of the distribution of the white-dwarf binary systems present in our Galaxy.

  5. Galactic Compact Objects Section of the White Paper on the Status and Future of Ground-based TeV Gamma-ray Astronomy

    E-Print Network [OSTI]

    P. Kaaret; A. A. Abdo; J. Arons; M. Baring; W. Cui; B. Dingus; J. Finley; S. Funk; S. Heinz; B. Gaensler; A. Harding; E. Hays; J. Holder; D. Kieda; A. Konopelko; S. LeBohec; A. Levinson; I. Moskalenko; R. Mukherjee; R. Ong; M. Pohl; K. Ragan; P. Slane; A. Smith; D. Torres

    2008-10-03

    This is a report on the findings of the Galactic compact objects working group for the white paper on the status and future of TeV gamma-ray astronomy. The white paper is an APS commissioned document, and the full version has also been released and can be found on astro-ph. This section of the white paper discusses the potential of future ground-based gamma-ray experiments to advance our understanding of the physics of Galactic compact objects including pulsars, pulsar wind nebulae, and X-ray binaries.

  6. Galactic Compact Objects Section of the White Paper on the Status and Future of Ground-based TeV Gamma-ray Astronomy

    E-Print Network [OSTI]

    Kaaret, Philip; Arons, J; Baring, M; Cui, W; Dingus, B; Finley, J; Funk, S; Heinz, S; Gaensler, B; Harding, A; Hays, E; Holder, J; Kieda, D; Konopelko, A; Le Bohec, S; Levinson, A; Moskalenko, I; Mukherjee, R; Ong, R; Pohl, M; Ragan, K; Slane, P; Smith, A; Torres, D

    2008-01-01

    This is a report on the findings of the Galactic compact objects working group for the white paper on the status and future of TeV gamma-ray astronomy. The white paper is an APS commissioned document, and the full version has also been released and can be found on astro-ph. This section of the white paper discusses the potential of future ground-based gamma-ray experiments to advance our understanding of the physics of Galactic compact objects including pulsars, pulsar wind nebulae, and X-ray binaries.

  7. White Oak Dam stability analysis. Volume I

    SciTech Connect (OSTI)

    Ahmed, S.B.

    1994-01-01

    A parametric study was conducted to evaluate the stability of the White Oak Dam (WOD) embankment and foundation. Slope stability analyses were performed for the upper and lower bound soil properties at three sections of the dam using the PCSTABL4 computer program. Minimum safety factors were calculated for the applicable seismic and static loading conditions. Liquefaction potential of the dam embankment and foundation solid during the seismic event was assessed by using simplified procedures. The WOD is classified as a low hazard facility and the Evaluation Basis Earthquake (EBE) is defined as an earthquake with a magnitude of m{sub b} = 5.6 and a Peak Ground Accelerator (PGA) of 0.13 g. This event is approximately equivalent to a Modified Mercalli Intensity of VI-VIII. The EBE is used to perform the seismic evaluation for slope stability and liquefaction potential. Results of the stability analyses and the liquefaction assessment lead to the conclusion that the White Oak Dam is safe and stable for the static and the seismic events defined in this study. Ogden Environmental, at the request of MMES, has checked and verified the calculations for the critical loading conditions and performed a peer review of this report. Ogden has determined that the WOD is stable under the defined static and seismic loading conditions and the embankment materials are in general not susceptible to liquefaction.

  8. From Pinholes to Black Holes

    SciTech Connect (OSTI)

    Fenimore, Edward E.

    2014-10-06

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

  9. On Thermodynamics of 2d Black Holes in Brane Inflationary Potentials

    E-Print Network [OSTI]

    A. Belhaj; M. Chabab; H. El Moumni; M. B. Sedra; A. Segui

    2014-01-29

    Inspired from the inflation brane world cosmology, we study the thermodynamics of a black hole solution in two dimensional dilaton gravity with an arctangent potential background. We first derive the two dimensional black hole geometry, then we examine its asymptotic behaviors. More precisely, we find that such behaviors exhibit properties appearing in some known cases including the Anti de Sitter and the Schwarzchild black holes. Using the complex path method, we compute the Hawking radiation. The entropy function can be related to the value of the potential at the horizon.

  10. On Heat Properties of AdS Black Holes in Higher Dimensions

    E-Print Network [OSTI]

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

    2015-07-01

    We investigate the heat properties of AdS Black Holes in higher dimensions. We consider the study of the corresponding thermodynamical properties including the heat capacity explored in the determination of the black hole stability. In particular, we compute the heat latent. To overcome the instability problem, the Maxwell construction, in the (T,S)-plane, is elaborated. This method is used to modify the the Hawking-Page phase structure by removing the negative heat capacity regions. Then, we discuss the thermodynamic cycle and the heat engines using the way based on the extraction of the work from a black hole solution.

  11. Extremal Higher Spin Black Holes

    E-Print Network [OSTI]

    Máximo Bañados; Alejandra Castro; Alberto Faraggi; Juan I. Jottar

    2015-11-30

    The gauge sector of three-dimensional higher spin gravities can be formulated as a Chern-Simons theory. In this context, a higher spin black hole corresponds to a flat connection with suitable holonomy (smoothness) conditions which are consistent with the properties of a generalized thermal ensemble. Building on these ideas, we discuss a definition of black hole extremality which is appropriate to the topological character of 3d higher spin theories. Our definition can be phrased in terms of the Jordan class of the holonomy around a non-contractible (angular) cycle, and we show that it is compatible with the zero-temperature limit of smooth black hole solutions. While this notion of extremality does not require nor implies the existence of supersymmetry, we exemplify its consequences in the context of sl(3|2) + sl(3|2) Chern-Simons theory. Remarkably, while as usual not all extremal solutions preserve supersymmetries, we find that the higher spin setup allows for non-extremal supersymmetric black hole solutions as well. Furthermore, we discuss our results from the perspective of the holographic duality between sl(3|2) + sl(3|2) Chern-Simons theory and two-dimensional CFTs with W_{(3|2)} symmetry, the simplest higher spin extension of the N=2 super-Virasoro algebra. In particular, we compute W_{(3|2)} BPS bounds at the full quantum level, and relate their semiclassical limit to extremal black hole or conical defect solutions in the 3d bulk. Along the way, we discuss the role of the spectral flow automorphism and provide a conjecture for the form of the semiclassical BPS bounds in general N=2 two-dimensional CFTs with extended symmetry algebras.

  12. Course may include: Research in Education

    E-Print Network [OSTI]

    Course may include: Research in Education Statistics in Education Theories of Educational Admin Policy Analysis Sociological Aspects of Education Approaches to Literacy Development Information and Communication Technologies Issues in Education Final Project Seminar Master of Education Educational

  13. Gas storage materials, including hydrogen storage materials

    DOE Patents [OSTI]

    Mohtadi, Rana F; Wicks, George G; Heung, Leung K; Nakamura, Kenji

    2014-11-25

    A material for the storage and release of gases comprises a plurality of hollow elements, each hollow element comprising a porous wall enclosing an interior cavity, the interior cavity including structures of a solid-state storage material. In particular examples, the storage material is a hydrogen storage material, such as a solid state hydride. An improved method for forming such materials includes the solution diffusion of a storage material solution through a porous wall of a hollow element into an interior cavity.

  14. Gas storage materials, including hydrogen storage materials

    DOE Patents [OSTI]

    Mohtadi, Rana F; Wicks, George G; Heung, Leung K; Nakamura, Kenji

    2013-02-19

    A material for the storage and release of gases comprises a plurality of hollow elements, each hollow element comprising a porous wall enclosing an interior cavity, the interior cavity including structures of a solid-state storage material. In particular examples, the storage material is a hydrogen storage material such as a solid state hydride. An improved method for forming such materials includes the solution diffusion of a storage material solution through a porous wall of a hollow element into an interior cavity.

  15. 100 LPW 800 Lm Warm White LED

    SciTech Connect (OSTI)

    Decai Sun

    2010-10-31

    An illumination grade warm white (WW) LED, having correlated color temperature (CCT) between 2800 K and 3500K and capable of producing 800 lm output at 100 lm/W, has been developed in this program. The high power WW LED is an ideal source for use as replacement for incandescent, and Halogen reflector and general purpose lamps of similar lumen value. Over the two year period, we have made following accomplishments: developed a high power warm white LED product and made over 50% improvements in light output and efficacy. The new high power WW LED product is a die on ceramic surface mountable LED package. It has four 1x1 mm{sup 2} InGaN pump dice flip chip attached to a ceramic submount in 2x2 array, covered by warm white phosphor ceramic platelets called Lumiramicâ?¢ and an overmolded silicone lens encapsulating the LED array. The performance goal was achieved through breakthroughs in following key areas: (1) High efficiency pump LED development through pump LED active region design and epi growth quality improvement (funded by internal programs). (2) Increase in injection efficiency (IE) represented by reduction in forward voltage (V{sub f}) through the improvement of the silver-based p-contact and a reduction in spreading resistance. The injection efficiency was increased from 80% at the start of the program to 96% at the end of the program at 700 mA/mm{sup 2}. (3) Improvement in thermal design as represented by reduction in thermal resistance from junction to case, through improvement of the die to submount connection in the thin film flip chip (TFFC) LED and choosing the submount material of high thermal conductivity. A thermal resistance of 1.72 K/W was demonstrated for the high power LED package. (4) Improvement in extraction efficiency from the LED package through improvement of InGaN die level and package level optical extraction efficiency improvement. (5) Improvement in phosphor system efficiency by improving the lumen equivalent (LE) and phosphor package efficiency (PPE) through improvement in phosphor-package interactions. Another achievement in the development of the phosphor integration technology is the demonstration of tight color control. The high power WW LED product developed has been proven to have good reliability. The manufacturing of the product will be done in Philips Lumiledsâ?? LUXEON Rebel production line which has produced billions of high power LEDs. The first high power WW LED product will be released to the market in 2011.

  16. Dilatonic wormholes: construction, operation, maintenance and collapse to black holes

    E-Print Network [OSTI]

    Sean A. Hayward; Sung-Won Kim; Hyunjoo Lee

    2001-10-18

    The CGHS two-dimensional dilaton gravity model is generalized to include a ghost Klein-Gordon field, i.e. with negative gravitational coupling. This exotic radiation supports the existence of static traversible wormhole solutions, analogous to Morris-Thorne wormholes. Since the field equations are explicitly integrable, concrete examples can be given of various dynamic wormhole processes, as follows. (i) Static wormholes are constructed by irradiating an initially static black hole with the ghost field. (ii) The operation of a wormhole to transport matter or radiation between the two universes is described, including the back-reaction on the wormhole, which is found to exhibit a type of neutral stability. (iii) It is shown how to maintain an operating wormhole in a static state, or return it to its original state, by turning up the ghost field. (iv) If the ghost field is turned off, either instantaneously or gradually, the wormhole collapses into a black hole.

  17. Handling Whiting Aboard Fishing Vessels JOSEPH J. L1CCIARDELLO

    E-Print Network [OSTI]

    Handling Whiting Aboard Fishing Vessels JOSEPH J. L1CCIARDELLO Introduction The same fundamental principles for handling fresh fish in general aboard fishing vessels apply to whiting. There- fore, this article will review the factors which influence the quality of fish aboard fishing boats and will offer re

  18. % of non-featureless pixels SNOW WHITE MIRROR

    E-Print Network [OSTI]

    Nebel, Jean-Christophe

    Legend % of non-featureless pixels SNOW WHITE MIRROR Daniel Collins Supervisor: Jean and attractiveness. They indicate that the more symmetrical a person's face is the more attractive they are. The Snow perspective. A virtual Snow White mirror was created to analyse facial symmetry and produce symmetry

  19. Chaos expansion of heat equations with white noise potentials

    E-Print Network [OSTI]

    Hu, Yaozhong

    2002-02-01

    The asymptotic behavior as t --> infinity of the solution to the following stochastic heat equations [GRAPHICS] is investigated, where w is a space-time white noise or a space white noise. The use of lozenge means that the stochastic integral of 10...

  20. A wide binary trigger for white dwarf pollution

    E-Print Network [OSTI]

    Bonsor, Amy

    2015-01-01

    Metal pollution in white dwarf atmospheres is likely to be a signature of remnant planetary systems. Most explanations for this pollution predict a sharp decrease in the number of polluted systems with white dwarf cooling age. Observations do not confirm this trend, and metal pollution in old (1-5 Gyr) white dwarfs is difficult to explain. We propose an alternative, time-independent mechanism to produce the white dwarf pollution. The orbit of a wide binary companion can be perturbed by Galactic tides, approaching close to the primary star for the first time after billions of years of evolution on the white dwarf branch. We show that such a close approach perturbs a planetary system orbiting the white dwarf, scattering planetesimals onto star-grazing orbits, in a manner that could pollute the white dwarf's atmosphere. Our estimates find that this mechanism is likely to contribute to metal pollution, alongside other mechanisms, in up to a few percent of an observed sample of white dwarfs with wide binary compan...

  1. WHITING SCHOOL OF ENGINEERING Rising to the Challenge

    E-Print Network [OSTI]

    Ghosh, Somnath

    to knowledge, engineering human health, and improving global well-being and security. To support1 2 WHITING SCHOOL OF ENGINEERING Rising to the Challenge: The Campaign for Johns Hopkins Whiting School of Engineering Wyman Park Building, Suite 400 3400 North Charles Street Baltimore, Maryland 21218

  2. Call No. Title Author Location Gilbert White Collection

    E-Print Network [OSTI]

    US Army Corps of Engineers

    development in Sub-Saharan Africa : an agenda for action. World Bank. Hist-White TH7413.S45 1 Accelerating the acceptance of solar heating : North American experience and international implicati Sewell, W. R. Derrick. IWR-White TD345.A33 19 Achieving success in community water supply and sanitation projects Chandler

  3. Magnetic wormholes and black universes with invisible ghosts

    E-Print Network [OSTI]

    K. A. Bronnikov; P. A. Korolyov

    2015-03-10

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

  4. Horizon of quantum black holes in various dimensions

    E-Print Network [OSTI]

    Casadio, Roberto; Giugno, Andrea; Mureika, Jonas

    2015-01-01

    We adapt the horizon wave-function formalism to describe massive static spherically symmetric sources in a general $(1+D)$-dimensional space-time, for $D>3$ and including the $D=1$ case. We find that the probability $P_{\\rm BH} $ that such objects are (quantum) black holes behaves similarly to the probability in the $(3+1)$ framework for $D> 3$. In fact, for $D\\ge 3$, the probability increases towards unity as the mass grows above the relevant $D$-dimensional Planck scale $m_D$, the faster the larger $D$. In contrast, for $D=1$, we find the probability is comparably larger for smaller masses, but $P_{\\rm BH} < 0.5$, suggesting that such lower dimensional black holes are purely quantum and not classical objects. This result is consistent with recent observations that sub-Planckian black holes are governed by an effective two-dimensional gravitation theory. Lastly, we derive Generalised Uncertainty Principle relations for the black holes under consideration, and for all cases find a minimum length scale $L_D...

  5. Quasi-black holes: general features and purely field configurations

    E-Print Network [OSTI]

    K. A. Bronnikov; O. B. Zaslavskii

    2015-04-27

    Objects that are on the threshold of forming the horizon but never collapse are called quasi-black holes (QBHs). We discuss the properties of the general spherically symmetric QBH metric without addressing its material source, including its limiting cases as the corresponding small parameter tends to zero. We then show that QBHs can exist among self-gravitating configurations of electromagnetic and dilatonic scalar fields without matter. These general results are illustrated by explicit examples of exact solutions.

  6. The Spanish Square Kilometre Array White Book

    E-Print Network [OSTI]

    Pulido, J A Acosta; Alberdi, A; Alcolea, J; Alfaro, E J; Alonso-Herrero, A; Anglada, G; Arnalte-Mur, P; Ascasibar, Y; Ascaso, B; Azulay, R; Bachiller, R; Baez-Rubio, A; Battaner, E; Blasco, J; Brook, C B; Bujarrabal, V; Busquet, G; Caballero-Garcia, M D; Carrasco-Gonzalez, C; Casares, J; Castro-Tirado, A J; Colina, L; Colomer, F; de Gregorio-Monsalvo, I; del Olmo, A; Desmurs, J-F; Diego, J M; Dominguez-Tenreiro, R; Estalella, R; Fernandez-Soto, A; Florido, E; Font, J; Font, J A; Fuente, A; Garcia-Burillo, S; Garcia-Benito, R; Garcia-Lorenzo, B; de Paz, A Gil; Girart, J M; Goicoechea, J R; Gomez, J F; Gonzalez-Garcia, M; Gonzalez-Martin, O; Gonzalez-Serrano, J I; Gorgas, J; Gorosabel, J; Guijarro, A; Guirado, J C; Hernandez-Garcia, L; Hernandez-Monteagudo, C; Herranz, D; Herrero-Illana, R; Hu, Y-D; Huelamo, N; Huertas-Company, M; Iglesias-Paramo, J; Jeong, S; Jimenez-Serra, I; Knapen, J H; Lineros, R A; Lisenfeld, U; Marcaide, J M; Marquez, I; Marti, J; Marti, J M; Martinez-Gonzalez, E; Martin-Pintado, J; Marti-Vidal, I; Masegosa, J; Mayen-Gijon, J M; Mezcua, M; Mimica, S/ Migliari P; Moldon, J; Morata, O; Negueruela, I; Oates, S R; Osorio, M; Palau, A; Paredes, J M; Perea, J; Perez-Gonzalez, P G; Perez-Montero, E; Perez-Torres, M A; Perucho, M; Planelles, S; Pons, J A; Prieto, A; Quilis, V; Ramirez-Moreta, P; Almeida, C Ramos; Rea, N; Ribo, M; Rioja, M J; Espinosa, J M Rodriguez; Ros, E; Rubiño-Martin, J A; Ruiz-Granados, B; Sabater, J; Sanchez, M A P; Usero, A; Verdes-Montenegro, L; Vidal-Garcia, A; Vielva, P; Vilchez, J; Zhang, B-B

    2015-01-01

    The Square Kilometre Array (SKA) is called to revolutionise essentially all areas of Astrophysics. With a collecting area of about a square kilometre, the SKA will be a transformational instrument, and its scientific potential will go beyond the interests of astronomers. Its technological challenges and huge cost requires a multinational effort, and Europe has recognised this by putting the SKA on the roadmap of the European Strategy Forum for Research Infrastructures (ESFRI). The Spanish SKA White Book is the result of the coordinated effort of 119 astronomers from 40 different research centers. The book shows the enormous scientific interest of the Spanish astronomical community in the SKA and warrants an optimum scientific exploitation of the SKA by Spanish researchers, if Spain enters the SKA project.

  7. TIDAL NOVAE IN COMPACT BINARY WHITE DWARFS

    SciTech Connect (OSTI)

    Fuller, Jim; Lai Dong [Department of Astronomy, Cornell University, Ithaca, NY 14850 (United States)

    2012-09-01

    Compact binary white dwarfs (WDs) undergoing orbital decay due to gravitational radiation can experience significant tidal heating prior to merger. In these WDs, the dominant tidal effect involves the excitation of outgoing gravity waves in the inner stellar envelope and the dissipation of these waves in the outer envelope. As the binary orbit decays, the WDs are synchronized from outside in (with the envelope synchronized first, followed by the core). We examine the deposition of tidal heat in the envelope of a carbon-oxygen WD and study how such tidal heating affects the structure and evolution of the WD. We show that significant tidal heating can occur in the star's degenerate hydrogen layer. This layer heats up faster than it cools, triggering runaway nuclear fusion. Such 'tidal novae' may occur in all WD binaries containing a CO WD, at orbital periods between 5 minutes and 20 minutes, and precede the final merger by 10{sup 5}-10{sup 6} years.

  8. Heat Equations with Fractional White Noise Potentials

    SciTech Connect (OSTI)

    Hu, Y. [Department of Mathematics, University of Kansas, 405 Snow Hall, Lawrence, KS 66045-2142 (United States)], E-mail: hu@math.ukans.edu

    2001-07-01

    This paper is concerned with the following stochastic heat equations: ({partial_derivative}u{sub t}(x))/({partial_derivative}t=1/2 u{sub t}(x)+{omega}{sup H}.u{sub t}(x)), x element of {sup d}, t>0, where w{sup H} is a time independent fractional white noise with Hurst parameter H=(h{sub 1}, h{sub 2},..., h{sub d}) , or a time dependent fractional white noise with Hurst parameter H=(h{sub 0}, h{sub 1},..., h{sub d}) . Denote | H | =h{sub 1}+h{sub 2}+...+h{sub d} . When the noise is time independent, it is shown that if 1/2 d-1 , then the solution is in L{sub 2} and the L{sub 2} -Lyapunov exponent of the solution is estimated. When the noise is time dependent, it is shown that if 1/2 d- 2 /( 2h{sub 0}-1 ) , the solution is in L{sub 2} and the L{sub 2} -Lyapunov exponent of the solution is also estimated. A family of distribution spaces S{sub {rho}} , {rho} element of RR , is introduced so that every chaos of an element in S{sub {rho}} is in L{sub 2} . The Lyapunov exponents in S{sub {rho}} of the solution are also estimated.

  9. Light extraction enhanced white light-emitting diodes with multi-layered phosphor configuration

    E-Print Network [OSTI]

    You, Jiun Pyng; Tran, Nguyen T.; Shi, Frank G.

    2010-01-01

    for general white LED lighting. ©2010 Optical Society offor general white LED lighting. #122987 - $15.00 USD (C)state lighting: Failure analysis of white LEDs,” J. Cryst.

  10. Scramjet including integrated inlet and combustor

    SciTech Connect (OSTI)

    Kutschenreuter, P.H. Jr.; Blanton, J.C.

    1992-02-04

    This patent describes a scramjet engine. It comprises: a first surface including an aft facing step; a cowl including: a leading edge and a trailing edge; an upper surface and a lower surface extending between the leading edge and the trailing edge; the cowl upper surface being spaced from and generally parallel to the first surface to define an integrated inlet-combustor therebetween having an inlet for receiving and channeling into the inlet-combustor supersonic inlet airflow; means for injecting fuel into the inlet-combustor at the step for mixing with the supersonic inlet airflow for generating supersonic combustion gases; and further including a spaced pari of sidewalls extending between the first surface to the cowl upper surface and wherein the integrated inlet-combustor is generally rectangular and defined by the sidewall pair, the first surface and the cowl upper surface.

  11. Electric Power Monthly, August 1990. [Glossary included

    SciTech Connect (OSTI)

    Not Available

    1990-11-29

    The Electric Power Monthly (EPM) presents monthly summaries of electric utility statistics at the national, Census division, and State level. The purpose of this publication is to provide energy decisionmakers with accurate and timely information that may be used in forming various perspectives on electric issues that lie ahead. Data includes generation by energy source (coal, oil, gas, hydroelectric, and nuclear); generation by region; consumption of fossil fuels for power generation; sales of electric power, cost data; and unusual occurrences. A glossary is included.

  12. The White Dwarf -- White Dwarf galactic background in the LISA data

    E-Print Network [OSTI]

    Edlund, J A; Królak, A; Nelemans, G; Edlund, Jeffrey A.; Tinto, Massimo; Krolak, Andrzej; Nelemans, Gijs

    2005-01-01

    LISA (Laser Interferometer Space Antenna) is a proposed space mission, which will use coherent laser beams exchanged between three remote spacecraft to detect and study low-frequency cosmic gravitational radiation. In the low-part of its frequency band, the LISA strain sensitivity will be dominated by the incoherent superposition of hundreds of millions of gravitational wave signals radiated by inspiraling white-dwarf binaries present in our own galaxy. In order to estimate the magnitude of the LISA response to this background, we have simulated a synthesized population that recently appeared in the literature. We find the amplitude of the galactic white-dwarf binary background in the LISA data to be modulated in time, reaching a minimum equal to about twice that of the LISA noise for a period of about two months around the time when the Sun-LISA direction is roughly oriented towards the Autumn equinox. Since the galactic white-dwarfs background will be observed by LISA not as a stationary but rather as a cyc...

  13. Simulation of the White Dwarf -- White Dwarf galactic background in the LISA data

    E-Print Network [OSTI]

    Edlund, J A; Królak, A; Nelemans, G; Edlund, Jeffrey A.; Tinto, Massimo; Kr\\'olak, Andrzej; Nelemans, Gijs

    2005-01-01

    LISA (Laser Interferometer Space Antenna) is a proposed space mission, which will use coherent laser beams exchanged between three remote spacecraft to detect and study low-frequency cosmic gravitational radiation. In the low-part of its frequency band, the LISA strain sensitivity will be dominated by the incoherent superposition of hundreds of millions of gravitational wave signals radiated by inspiraling white-dwarf binaries present in our own galaxy. In order to estimate the magnitude of the LISA response to this background, we have simulated a synthesized population that recently appeared in the literature. We find the amplitude of the galactic white-dwarf binary background in the LISA data to be modulated in time, reaching a minimum equal to about twice that of the LISA noise for a period of about two months around the time when the Sun-LISA direction is roughly oriented towards the Autumn equinox. Since the galactic white-dwarfs background will be observed by LISA not as a stationary but rather as a cyc...

  14. LOCATION OF SERVICES 496 White Spruce Boulevard

    E-Print Network [OSTI]

    Portman, Douglas

    disorders including anorexia nervosa,· bulimia, or binge eating and obesity Child and adolescent issues

  15. LOCATION OF SERVICES 550 White Spruce Boulevard

    E-Print Network [OSTI]

    Goldman, Steven A.

    disorders including anorexia nervosa,· bulimia, or binge eating and obesity Child and adolescent issues

  16. Black Hole Thermodynamics and Electromagnetism

    E-Print Network [OSTI]

    Burra G. Sidharth

    2005-07-15

    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.

  17. Quantum chaos inside Black Holes

    E-Print Network [OSTI]

    Addazi, Andrea

    2015-01-01

    We show how semiclassical black holes can be reinterpreted as an effective geometry, composed of a large ensamble of horizonless naked singularities (eventually smoothed at the Planck scale). We call this new items {\\it frizzyballs}, which can be rigorously defined by euclidean path integral approach. This has interesting implications regarding information paradoxes. We demonstrate that infalling information will chaotically propagate inside this system before going to the full quantum gravity regime (Planck scale).

  18. Quantum chaos inside Black Holes

    E-Print Network [OSTI]

    Andrea Addazi

    2015-08-30

    We show how semiclassical black holes can be reinterpreted as an effective geometry, composed of a large ensamble of horizonless naked singularities (eventually smoothed at the Planck scale). We call this new items {\\it frizzyballs}, which can be rigorously defined by euclidean path integral approach. This has interesting implications regarding information paradoxes. We demonstrate that infalling information will chaotically propagate inside this system before going to the full quantum gravity regime (Planck scale).

  19. Classical Black Holes Are Hot

    E-Print Network [OSTI]

    Erik Curiel

    2014-11-09

    In the early 1970s it is was realized that there is a striking formal analogy between the Laws of black-hole mechanics and the Laws of classical thermodynamics. Before the discovery of Hawking radiation, however, it was generally thought that the analogy was only formal, and did not reflect a deep connection between gravitational and thermodynamical phenomena. It is still commonly held that the surface gravity of a stationary black hole can be construed as a true physical temperature and its area as a true entropy only when quantum effects are taken into account; in the context of classical general relativity alone, one cannot cogently construe them so. Does the use of quantum field theory in curved spacetime offer the only hope for taking the analogy seriously? I think the answer is `no'. To attempt to justify that answer, I shall begin by arguing that the standard argument to the contrary is not physically well founded, and in any event begs the question. Looking at the various ways that the ideas of "temperature" and "entropy" enter classical thermodynamics then will suggest arguments that, I claim, show the analogy between classical black-hole mechanics and classical thermodynamics should be taken more seriously, without the need to rely on or invoke quantum mechanics. In particular, I construct an analogue of a Carnot cycle in which a black hole "couples" with an ordinary thermodynamical system in such a way that its surface gravity plays the role of temperature and its area that of entropy. Thus, the connection between classical general relativity and classical thermodynamics on their own is already deep and physically significant, independent of quantum mechanics.

  20. MOTIVATION INCLUDED OR EXCLUDED FROM Mihaela Cocea

    E-Print Network [OSTI]

    Cocea, Mihaela

    MOTIVATION ­ INCLUDED OR EXCLUDED FROM E-LEARNING Mihaela Cocea National College of Ireland Mayor, Dublin 1, Ireland sweibelzahl@ncirl.ie ABSTRACT The learners' motivation has an impact on the quality-Learning, motivation has been mainly considered in terms of instructional design. Research in this direction suggests

  1. Energy Consumption of Personal Computing Including Portable

    E-Print Network [OSTI]

    Namboodiri, Vinod

    processing unit (CPU) processing power and capacity of mass storage devices doubles every 18 months. Such growth in both processing and storage capabilities fuels the production of ever more powerful portableEnergy Consumption of Personal Computing Including Portable Communication Devices Pavel Somavat1

  2. Course may include: Research in Education

    E-Print Network [OSTI]

    Development Information and Communication Technologies Issues in Education Final Project Seminar Master, the Final Project Seminar. This graduate program will allow you to develop your skills and knowledgeCourse may include: Research in Education Qualitative Methods in Educational Research Fundamentals

  3. Communication in automation, including networking and wireless

    E-Print Network [OSTI]

    Antsaklis, Panos

    Communication in automation, including networking and wireless Nicholas Kottenstette and Panos J and networking in automation is given. Digital communication fundamentals are reviewed and networked control are presented. 1 Introduction 1.1 Why communication is necessary in automated systems Automated systems use

  4. White Kids: Identity Construction, Critical Mass, and Symbolic Exclusion in High School Cliques and other Groups

    E-Print Network [OSTI]

    Lueck, Kerstin; Steffen, Hayley

    2011-01-01

    M. (1997). The social construction of Whiteness. In R.bre White Kids: Identity Construction, Critical Mass, andKeywords: Identity Construction, Symbolic Exclusion,

  5. President Obama Announces New Advances and Commitments to Support Tribes at White House Tribal Nations Conference

    Broader source: Energy.gov [DOE]

    The White House brought together tribal leaders from federally recognized tribes to participate in the 7th Annual White House Tribal Nations Conference on Nov. 5, 2015.

  6. The circulating hemocytes of the white shrimp, Penaeus setiferus: origin, abundance, morphology, and function 

    E-Print Network [OSTI]

    Fontaine, Clark Timothy

    1978-01-01

    and agranular. Observations . bow the larger included granules to be positive for Sudan Black, a lipid stain. Blood cells were cultured in vitro for descriptions of viable cell configuration. The fine structure of each cell type is described. The furction...? Function 30 40 General? 44 CGNCLUSION? LITERATURE CITED VITA 46 47 53 LIST OF TABLES Table I. Composition of modified lobster hemolymph medium (MLHN) ? after Paterson and Stewart (1974) 16 Tab le II. Average number of blood cells/mm for each...

  7. Subterranean barriers including at least one weld

    DOE Patents [OSTI]

    Nickelson, Reva A.; Sloan, Paul A.; Richardson, John G.; Walsh, Stephanie; Kostelnik, Kevin M.

    2007-01-09

    A subterranean barrier and method for forming same are disclosed, the barrier including a plurality of casing strings wherein at least one casing string of the plurality of casing strings may be affixed to at least another adjacent casing string of the plurality of casing strings through at least one weld, at least one adhesive joint, or both. A method and system for nondestructively inspecting a subterranean barrier is disclosed. For instance, a radiographic signal may be emitted from within a casing string toward an adjacent casing string and the radiographic signal may be detected from within the adjacent casing string. A method of repairing a barrier including removing at least a portion of a casing string and welding a repair element within the casing string is disclosed. A method of selectively heating at least one casing string forming at least a portion of a subterranean barrier is disclosed.

  8. Photoactive devices including porphyrinoids with coordinating additives

    DOE Patents [OSTI]

    Forrest, Stephen R; Zimmerman, Jeramy; Yu, Eric K; Thompson, Mark E; Trinh, Cong; Whited, Matthew; Diev, Vlacheslav

    2015-05-12

    Coordinating additives are included in porphyrinoid-based materials to promote intermolecular organization and improve one or more photoelectric characteristics of the materials. The coordinating additives are selected from fullerene compounds and organic compounds having free electron pairs. Combinations of different coordinating additives can be used to tailor the characteristic properties of such porphyrinoid-based materials, including porphyrin oligomers. Bidentate ligands are one type of coordinating additive that can form coordination bonds with a central metal ion of two different porphyrinoid compounds to promote porphyrinoid alignment and/or pi-stacking. The coordinating additives can shift the absorption spectrum of a photoactive material toward higher wavelengths, increase the external quantum efficiency of the material, or both.

  9. A Very Low-Luminosity, Very Cool, DC White Dwarf

    E-Print Network [OSTI]

    Hugh Harris; Conard Dahn; Frederick Vrba; Arne Henden; James Liebert; Gary Schmidt; Neill Reid

    1999-06-03

    The star LHS 3250 is found to be a white dwarf at a distance of 30 pc. Its absolute magnitudes (M_V = 15.72; M_bol = 16.2) put it among the least-luminous white dwarfs known. Its optical spectrum shows no features, indicating it has a DC classification, and it shows no detectable polarization, indicating it does not have a very strong magnetic field. However, its broadband colors show it to have a unique spectral energy distribution, and it stands out from all other stars in BVI and other broadband photometric surveys. We discuss these properties, and conclude that LHS 3250 must be an extremely cool white dwarf with strong collision-induced absorption at red-infrared wavelengths from molecular hydrogen, in accord with models for very cool white dwarf atmospheres. If so, it is the first such star known, and the first star to provide observational evidence supporting these models. It suggests that other very cool white dwarfs, both halo white dwarfs and the oldest disk white dwarfs, also may have colors affected by similar absorption. The atmospheric composition of LHS 3250 is not known, and therefore its temperature is poorly determined. It may be a helium-core star with a mass 0.3-0.45 M_solar and a product of mass-transfer in a close binary system. However, until its temperature is better known, its mass and age remain uncertain.

  10. Power generation method including membrane separation

    DOE Patents [OSTI]

    Lokhandwala, Kaaeid A. (Union City, CA)

    2000-01-01

    A method for generating electric power, such as at, or close to, natural gas fields. The method includes conditioning natural gas containing C.sub.3+ hydrocarbons and/or acid gas by means of a membrane separation step. This step creates a leaner, sweeter, drier gas, which is then used as combustion fuel to run a turbine, which is in turn used for power generation.

  11. Rotor assembly including superconducting magnetic coil

    DOE Patents [OSTI]

    Snitchler, Gregory L. (Shrewsbury, MA); Gamble, Bruce B. (Wellesley, MA); Voccio, John P. (Somerville, MA)

    2003-01-01

    Superconducting coils and methods of manufacture include a superconductor tape wound concentrically about and disposed along an axis of the coil to define an opening having a dimension which gradually decreases, in the direction along the axis, from a first end to a second end of the coil. Each turn of the superconductor tape has a broad surface maintained substantially parallel to the axis of the coil.

  12. Nuclear reactor shield including magnesium oxide

    DOE Patents [OSTI]

    Rouse, Carl A. (Del Mar, CA); Simnad, Massoud T. (La Jolla, CA)

    1981-01-01

    An improvement in nuclear reactor shielding of a type used in reactor applications involving significant amounts of fast neutron flux, the reactor shielding including means providing structural support, neutron moderator material, neutron absorber material and other components as described below, wherein at least a portion of the neutron moderator material is magnesium in the form of magnesium oxide either alone or in combination with other moderator materials such as graphite and iron.

  13. Electric power monthly, September 1990. [Glossary included

    SciTech Connect (OSTI)

    Not Available

    1990-12-17

    The purpose of this report is to provide energy decision makers with accurate and timely information that may be used in forming various perspectives on electric issues. The power plants considered include coal, petroleum, natural gas, hydroelectric, and nuclear power plants. Data are presented for power generation, fuel consumption, fuel receipts and cost, sales of electricity, and unusual occurrences at power plants. Data are compared at the national, Census division, and state levels. 4 figs., 52 tabs. (CK)

  14. Section on Extragalactic Science Topics of the White Paper on the Status and Future of Ground-Based TeV Gamma-Ray Astronomy

    E-Print Network [OSTI]

    Krawczynski, H; Beilicke, M; Blandford, R; Böttcher, M; Buckley, J; Carramiñana, A; Coppi, P; Dermer, C; Dingus, B; Dwek, E; Falcone, A; Fegan, S; Finley, J; Funk, S; Georganopoulos, M; Holder, J; Horan, D; Jones, T; Jung, I; Kaaret, Philip; Katz, J; Krennrich, F; Le Bohec, S; McEnery, J; Mukherjee, R; Ong, R; Perlman, E; Pohl, M; Ritz, S; Ryan, J; Sinnis, G; Vasilev, V; Urry, M; Weekes, T

    2008-01-01

    This is a report on the findings of the extragalactic science working group for the white paper on the status and future of TeV gamma-ray astronomy. The white paper was commissioned by the American Physical Society, and the full white paper can be found on astro-ph (arXiv:0810.0444). This detailed section discusses extragalactic science topics including active galactic nuclei, cosmic ray acceleration in galaxies, galaxy clusters and large scale structure formation shocks, and the study of the extragalactic infrared and optical background radiation. The scientific potential of ground based gamma-ray observations of Gamma-Ray Bursts and dark matter annihilation radiation is covered in other sections of the white paper.

  15. Section on Extragalactic Science Topics of the White Paper on the Status and Future of Ground-Based TeV Gamma-Ray Astronomy

    E-Print Network [OSTI]

    H. Krawczynski; A. M. Atoyan; M. Beilicke; R. Blandford; M. Boettcher; J. Buckley; A. Carraminana; P. Coppi; C. Dermer; B. Dingus; E. Dwek; A. Falcone; S. Fegan; J. Finley; S. Funk; M. Georganopoulos; J. Holder; D. Horan; T. Jones; I. Jung; P. Kaaret; J. Katz; F. Krennrich; S. LeBohec; J. McEnery; R. Mukherjee; R. Ong; E. Perlman; M. Pohl; S. Ritz; J. Ryan; G. Sinnis; V. Vassiliev; M. Urry; T. Weekes

    2008-12-03

    This is a report on the findings of the extragalactic science working group for the white paper on the status and future of TeV gamma-ray astronomy. The white paper was commissioned by the American Physical Society, and the full white paper can be found on astro-ph (arXiv:0810.0444). This detailed section discusses extragalactic science topics including active galactic nuclei, cosmic ray acceleration in galaxies, galaxy clusters and large scale structure formation shocks, and the study of the extragalactic infrared and optical background radiation. The scientific potential of ground based gamma-ray observations of Gamma-Ray Bursts and dark matter annihilation radiation is covered in other sections of the white paper.

  16. Boson shells harboring charged black holes

    SciTech Connect (OSTI)

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

    2010-11-15

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

  17. The return of the membrane paradigm? Black holes and strings in the water tap

    E-Print Network [OSTI]

    Vitor Cardoso; Oscar J. C. Dias; Leonardo Gualtieri

    2008-05-16

    Several general arguments indicate that the event horizon behaves as a stretched membrane. We propose using this relation to understand gravity and dynamics of black objects in higher dimensions. We provide evidence that (i) the gravitational Gregory-Laflamme instability has a classical counterpart in the Rayleigh-Plateau instability of fluids. Each known feature of the gravitational instability can be accounted for in the fluid model. These features include threshold mode, dispersion relation, time evolution and critical dimension of certain phase transitions. Thus, we argue that black strings break in much the same way as water from a faucet breaks up into small droplets. (ii) General rotating black holes can also be understood with this analogy. In particular, instability and bifurcation diagrams for black objects can easily be inferred. This correspondence can and should be used as a guiding tool to understand and explore physics of gravity in higher dimensions.

  18. On Thermodynamics of AdS Black Holes in M-Theory

    E-Print Network [OSTI]

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

    2015-09-07

    Motivated by a recent work on asymptotically AdS_4 black holes in M-theory, we investigate the thermodynamics and thermodynamical geometry of AdS black holes from M2 and M5-branes. Concretely, we consider AdS black holes in AdS_{p+2}\\times S^{11-p-2}, where p=2,5 by interpreting the number of M2 (and M5-branes) as a thermodynamical variable. We study the corresponding phase transition to examine their stabilities by calculating and discussing various thermodynamical quantities including the chemical potential. Then, we compute the thermodynamical curvatures from the Quevedo metric for M2 and M5-branes geometries to reconsider the stability of such black objects. The Quevedo metric singularities recover similar stability results provided by the phase transition program.

  19. Thermodynamic fluctuation in black string flow

    E-Print Network [OSTI]

    Meng Sun; Yong-Chang Huna

    2015-06-14

    It has long been noticed that Laudau-Lifshitz theory can be used to study the fluctuation of a system that contains a black hole. Since the black string can be constructed by extending n-dimensional black hole into one extra dimension. We study the fluctuation of black string flow with a Schwarzschlid-like metric in D=n+1 dimensional spacetime and a charged solution in D=5 dimensional spacetime and get the second moments of the fluctuation of the mass flux and charge flux.

  20. Thermodynamic fluctuation in black string flow

    E-Print Network [OSTI]

    Meng Sun; Yong-Chang Huang

    2015-05-11

    It has long been noticed that Laudau-Lifshitz theory can be used to study the fluctuation of a system that contains a black hole. Since the black string can be constructed by extending n-dimensional black hole into one extra dimension. We study the fluctuation of black string flow with a Schwarzschlid-like metric in D=n+1 dimensional spacetime and a charged solution in D=5 dimensional spacetime and get the second moments of the fluctuation of the mass flux and charge flux.

  1. Black carbon contribution to global warming

    SciTech Connect (OSTI)

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

    1996-12-31

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

  2. Lower Dimensional Black Holes: Inside and Out

    E-Print Network [OSTI]

    R. B. Mann

    1995-01-27

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

  3. Black Holes: from Speculations to Observations

    E-Print Network [OSTI]

    Thomas W. Baumgarte

    2006-04-13

    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.

  4. Rotating Black Holes and Coriolis Effect

    E-Print Network [OSTI]

    Wu, Xiaoning; Yuan, Pei-Hung; Cho, Chia-Jui

    2015-01-01

    In this work, we consider the fluid/gravity correspondence for general rotating black holes. By using the Petrov-like boundary condition in near horizon limit, we study the correspondence between gravitational perturbation and fluid equation. We find that the dual fluid equation for rotating black holes contains a Coriolis force term, which is closely related to the angular velocity of the black hole horizon. This can be seen as a dual effect for the frame-dragging effect of rotating black hole under the holographic picture.

  5. Rotating Black Holes and Coriolis Effect

    E-Print Network [OSTI]

    Xiaoning Wu; Yi Yang; Pei-Hung Yuan; Chia-Jui Cho

    2015-11-27

    In this work, we consider the fluid/gravity correspondence for general rotating black holes. By using the Petrov-like boundary condition in near horizon limit, we study the correspondence between gravitational perturbation and fluid equation. We find that the dual fluid equation for rotating black holes contains a Coriolis force term, which is closely related to the angular velocity of the black hole horizon. This can be seen as a dual effect for the frame-dragging effect of rotating black hole under the holographic picture.

  6. The Binary White Dwarf LHS 3236

    E-Print Network [OSTI]

    Harris, Hugh; Dupuy, Trent; Canzian, Blaise; Guetter, Harry; Hartkopf, William; Ireland, Michael; Leggett, Sandy; Levine, Stephen; Liu, Michael; Luginbuhl, Christian; Monet, Alice; Stone, Ronald; Subasavage, John; Tilleman, Trudy; Walker, Richard

    2013-01-01

    The white dwarf LHS 3236 (WD1639+153) is shown to be a double-degenerate binary, with each component having a high mass. Astrometry at the U.S. Naval Observatory gives a parallax and distance of 30.86 +/- 0.25 pc and a tangential velocity of 98 km/s, and reveals binary orbital motion. The orbital parameters are determined from astrometry of the photocenter over more than three orbits of the 4.0-year period. High-resolution imaging at the Keck Observatory resolves the pair with a separation of 31 and 124 mas at two epochs. Optical and near-IR photometry give a set of possible binary components. Consistency of all data indicates that the binary is a pair of DA stars with temperatures near 8000 and 7400 K and with masses of 0.93 and 0.91 M_solar; also possible, is a DA primary and a helium DC secondary with temperatures near 8800 and 6000 K and with masses of 0.98 and 0.69 M_solar. In either case, the cooling ages of the stars are ~3 Gyr and the total ages are <4 Gyr. The combined mass of the binary (1.66--1....

  7. The binary white dwarf LHS 3236

    SciTech Connect (OSTI)

    Harris, Hugh C.; Dahn, Conard C.; Canzian, Blaise; Guetter, Harry H.; Levine, Stephen E.; Luginbuhl, Christian B.; Monet, Alice K. B.; Stone, Ronald C.; Subasavage, John P.; Tilleman, Trudy; Walker, Richard L. [US Naval Observatory, 10391 West Naval Observatory Road, Flagstaff, AZ 86001-8521 (United States); Dupuy, Trent J.; Liu, Michael C. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Hartkopf, William I. [US Naval Observatory, 3450 Massachusetts Avenue, N.W., Washington, DC 20392-5420 (United States); Ireland, Michael J. [Department of Physics and Astronomy, Macquarie University, New South Wales, NSW 2109 (Australia); Leggett, S. K., E-mail: hch@nofs.navy.mil [Gemini Observatory, 670 N. Aohoku Place, Hilo, HI 96720 (United States)

    2013-12-10

    The white dwarf LHS 3236 (WD1639+153) is shown to be a double-degenerate binary, with each component having a high mass. Astrometry at the U.S. Naval Observatory gives a parallax and distance of 30.86 ± 0.25 pc and a tangential velocity of 98 km s{sup –1}, and reveals binary orbital motion. The orbital parameters are determined from astrometry of the photocenter over more than three orbits of the 4.0 yr period. High-resolution imaging at the Keck Observatory resolves the pair with a separation of 31 and 124 mas at two epochs. Optical and near-IR photometry give a set of possible binary components. Consistency of all data indicates that the binary is a pair of DA stars with temperatures near 8000 and 7400 K and with masses of 0.93 and 0.91 M {sub ?}; also possible is a DA primary and a helium DC secondary with temperatures near 8800 and 6000 K and with masses of 0.98 and 0.69 M {sub ?}. In either case, the cooling ages of the stars are ?3 Gyr and the total ages are <4 Gyr. The combined mass of the binary (1.66-1.84 M {sub ?}) is well above the Chandrasekhar limit; however, the timescale for coalescence is long.

  8. Thermonuclear detonations ensuing white dwarf mergers

    E-Print Network [OSTI]

    Dan, Marius; Brüggen, Marcus; Ramirez-Ruiz, Enrico; Rosswog, Stephan

    2015-01-01

    The merger of two white dwarfs (WDs) has for many years not been considered as the favoured model for the progenitor system of type Ia supernovae (SNe Ia). But recent years have seen a change of opinion as a number of studies, both observational and theoretical, have concluded that they should contribute significantly to the observed type Ia supernova rate. In this paper, we study the ignition and propagation of detonation through post-merger remnants and we follow the resulting nucleosynthesis up to the point where a homologous expansion is reached. In our study we cover the entire range of WD masses and compositions. For the emergence of a detonation we study several setups, guided by both merger remnants from our own simulations and by results taken from the literature. We carefully compare the nucleosynthetic yields of successful explosions with SN Ia observations. Only three of our models are consistent with all the imposed constraints and potentially lead to a standard type Ia event. The first one, a $0...

  9. L.A. Rebellion: Creating a New Black Cinema

    E-Print Network [OSTI]

    Sheppard, Samantha Noelle

    2011-01-01

    Creating a New Black Cinema Symposium Review by SamanthaCreating a New Black Cinema By the turn of the next century,in the development of Black cinema took place at UCLA in the

  10. Queering Black Gay Historiography: Performance, (Mis) Identifications, and Possibilities

    E-Print Network [OSTI]

    Fitzgerald, Thomas Howard

    2013-01-01

    In 1976 the black comedy Car Wash featured a black gay manthe a openly black sissy in the Car Wash as a character thatsaw the distribution of Car Wash with Antoino Fargas playing

  11. Likely detection of water-rich asteroid debris in a metal-polluted white dwarf

    E-Print Network [OSTI]

    Raddi, R; Koester, D; Farihi, J; Hermes, J J; Scaringi, S; Breedt, E; Girven, J

    2015-01-01

    The cool white dwarf SDSS J124231.07+522626.6 exhibits photospheric absorption lines of 8 distinct heavy elements in medium resolution optical spectra, notably including oxygen. The Teff = 13000 K atmosphere is helium-dominated, but the convection zone contains significant amounts of hydrogen and oxygen. The four most common rock-forming elements (O, Mg, Si, and Fe) account for almost all the accreted mass, totalling at least 1.2e+24 g, similar to the mass of Ceres. The time-averaged accretion rate is 2e+10 g/s, one of the highest rates inferred among all known metal-polluted white dwarfs. We note a large oxygen excess, with respect to the most common metal oxides, suggesting that the white dwarf accreted planetary debris with a water content of ~38 per cent by mass. This star, together with GD 61, GD 16, and GD 362, form a small group of outliers from the known population of evolved planetary systems accreting predominantly dry, rocky debris. This result strengthens the hypothesis that, integrated over the c...

  12. Ian R.White1 Russell Pickford2

    E-Print Network [OSTI]

    Ian R.White1 Russell Pickford2 John Wood3 J. Mark Skehel1 Bevan Gangadharan4 Paul Cutler1 1 Genomic protocols on the downstream processing of a test radiolabeled protein were stud- ied. The data confirms

  13. Celebrating Women's History Month with the White House Council...

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

    has said, no one working full time in this country should have to raise children in poverty. This Spring, the President will also host the first ever White House Summit on...

  14. A Young White Dwarf with an Infrared Excess

    E-Print Network [OSTI]

    Xu, S; Pantoja, B; Klein, B; Zuckerman, B; Su, K Y L; Meng, H Y A

    2015-01-01

    Using observations of Spitzer/IRAC, we report the serendipitous discovery of excess infrared emission from a single white dwarf PG 0010+280. At a temperature of 27,220 K and a cooling age of 16 Myr, it is the hottest and youngest white dwarf to display an excess at 3-8 $\\mu$m. The infrared excess can be fit by either an opaque dust disk within the tidal radius of the white dwarf or a 1300 K blackbody, possibly from an irradiated substellar object or a re-heated giant planet. PG 0010+280 has two unique properties that are different from white dwarfs with a dust disk: (i) relatively low emission at 8 $\\mu$m and (ii) non-detection of heavy elements in its atmosphere from high-resolution spectroscopic observations with Keck/HIRES. The origin of the infrared excess remains unclear.

  15. White County REMC- Residential Geothermal Heat Pump Rebate Program

    Office of Energy Efficiency and Renewable Energy (EERE)

    Additional rebates are available for White county REMC customers through the Power Moves program adminstered by the Wabash Valley Power Association.  Visit the Power Moves website for more inform...

  16. NextSTEPS White Paper: Three Routes Forward for Biofuels

    E-Print Network [OSTI]

    California at Davis, University of

    NextSTEPS White Paper: Three Routes Forward for Biofuels: Incremental, Transitional, and Leapfrog NOT CITE #12;Three Routes Forward for Biofuels: Incremental, Transitional, and Leapfrog 2 Contents ......................................................................................................................................12 1.a. The Need for Low Carbon Biofuels

  17. Advances in Chip Technology, Packaging Enable White LED Breakthroughs

    Broader source: Energy.gov [DOE]

    Significant advances in chip technology have enabled Cree, Inc.'s Santa Barbara Technology Center to demonstrate white LEDs with record efficacies as high as 74 lumens per watt - on par with...

  18. Public Interest Energy Research (PIER) Program White Paper

    E-Print Network [OSTI]

    Bromirski, Peter D.

    · Renewable Energy Technologies · Transportation In 2003, the California Energy Commission's PIER Program PROJECTIONS: 2000­2100 A White Paper from the California Energy Commission's California Climate Change Center Prepared for: California Energy Commission Prepared by: Scripps Institution

  19. White organic light-emitting diodes: Status and perspective

    E-Print Network [OSTI]

    Reineke, Sebastian

    White organic light-emitting diodes (OLEDs) are ultrathin, large-area light sources made from organic semiconductor materials. Over the past decades, much research has been spent on finding suitable materials to realize ...

  20. Texas white-tailed deer Internet harvest model 

    E-Print Network [OSTI]

    Garrett, Jennifer Nicole

    2009-05-15

    White-tailed deer (Odocoileus virginianus) is an intensively managed game species throughout Texas and the United States. Modeling is a tool that has been used to evaluate various management practices and their potential ...

  1. Optical panel system including stackable waveguides

    DOE Patents [OSTI]

    DeSanto, Leonard (Dunkirk, MD); Veligdan, James T. (Manorville, NY)

    2007-11-20

    An optical panel system including stackable waveguides is provided. The optical panel system displays a projected light image and comprises a plurality of planar optical waveguides in a stacked state. The optical panel system further comprises a support system that aligns and supports the waveguides in the stacked state. In one embodiment, the support system comprises at least one rod, wherein each waveguide contains at least one hole, and wherein each rod is positioned through a corresponding hole in each waveguide. In another embodiment, the support system comprises at least two opposing edge structures having the waveguides positioned therebetween, wherein each opposing edge structure contains a mating surface, wherein opposite edges of each waveguide contain mating surfaces which are complementary to the mating surfaces of the opposing edge structures, and wherein each mating surface of the opposing edge structures engages a corresponding complementary mating surface of the opposite edges of each waveguide.

  2. Simple Model of Membrane Proteins Including Solvent

    E-Print Network [OSTI]

    D. L. Pagan; A. Shiryayev; T. P. Connor; J. D. Gunton

    2006-03-04

    We report a numerical simulation for the phase diagram of a simple two dimensional model, similar to one proposed by Noro and Frenkel [J. Chem. Phys. \\textbf{114}, 2477 (2001)] for membrane proteins, but one that includes the role of the solvent. We first use Gibbs ensemble Monte Caro simulations to determine the phase behavior of particles interacting via a square-well potential in two dimensions for various values of the interaction range. A phenomenological model for the solute-solvent interactions is then studied to understand how the fluid-fluid coexistence curve is modified by solute-solvent interactions. It is shown that such a model can yield systems with liquid-liquid phase separation curves that have both upper and lower critical points, as well as closed loop phase diagrams, as is the case with the corresponding three dimensional model.

  3. Extraordinary vacuum black string solutions

    SciTech Connect (OSTI)

    Kim, Hyeong-Chan; Lee, Jungjai

    2008-01-15

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

  4. The Reduction of the Electron Abundance during the Pre-explosion Simmering in White Dwarf Supernovae

    E-Print Network [OSTI]

    David A. Chamulak; Edward F. Brown; F. X. Timmes; Kimberly Dupczak

    2008-02-28

    Prior to the explosion of a carbon-oxygen white dwarf in a Type Ia supernova there is a long "simmering," during which the 12C + 12C reaction gradually heats the white dwarf on a long (~ 1000 yr) timescale. Piro & Bildsten showed that weak reactions during this simmering set a maximum electron abundance Ye at the time of the explosion. We investigate the nuclear reactions during this simmering with a series of self-heating, at constant pressure, reaction network calculations. Unlike in AGB stars, proton captures onto 22Ne and heavier trace nuclei do not play a significant role. The 12C abundance is sufficiently high that the neutrons preferentially capture onto 12C, rather than iron group nuclei. As an aid to hydrodynamical simulations of the simmering phase, we present fits to the rates of heating, electron capture, change in mean atomic mass, and consumption of 12C in terms of the screened thermally averaged cross section for 12C + 12C. Our evaluation of the net heating rate includes contributions from electron captures into the 3.68 MeV excited state of 13C. This results in a slightly larger energy release, per 12C consumed, than that found by Piro & Bildsten, but less than that released for a burn to only 20Ne and 23Na. We compare our one-zone results to more accurate integrations over the white dwarf structure to estimate the amount of 12C that must be consumed to raise the white dwarf temperature, and hence to determine the net reduction of Ye during simmering.

  5. On the White Dwarf distances to Galactic Globular Clusters

    E-Print Network [OSTI]

    M. Salaris; S. Cassisi; E. Garcia-Berro; J. Isern; S. Torres

    2001-03-20

    We analyze in detail various possible sources of systematic errors on the distances of globular clusters derived by fitting a local template DA white dwarf sequence to the cluster counterpart (the so-called WD-fitting technique). We find that the unknown thickness of the hydrogen layer of white dwarfs in clusters plays a non negligible role. For reasonable assumptions - supported by the few sparse available observational constraints - about the unknown mass and thickness of the hydrogen layer for the cluster white dwarfs, a realistic estimate of the systematic error on the distance is within +-0.10 mag. However, particular combinations of white dwarf masses and envelope thicknesses - which at present cannot be excluded a priori - could produce larger errors. Contamination of the cluster DA sequence by non-DA white dwarfs introduces a very small systematic error of about -0.03 mag in the Mv/(V-I) plane, but in the Mv/(B-V) plane the systematic error amounts to ~ +0.20 mag. Contamination by white dwarfs with helium cores should not influence appreciably the WD-fitting distances. Finally, we obtain a derivative D((m-M)v)/D(E(B-V))~ -5.5 for the WD-fitting distances, which is very similar to the dependence found when using the Main Sequence fitting technique.

  6. Ages of White Dwarf-Red Subdwarf Systems

    E-Print Network [OSTI]

    Hektor Monteiro; Wei-Chun Jao; Todd Henry; John Subasavage; Thom Beaulieu

    2005-10-12

    We provide the first age estimates for two recently discovered white dwarf-red subdwarf systems, LHS 193AB and LHS 300AB. These unusual systems provide a new opportunity for linking the reliable age estimates for the white dwarfs to the (measurable) metallicities of the red subdwarfs. We have obtained precise photometry in the $V_{J}R_{KC}I_{KC}JH$ bands and spectroscopy covering from 6000\\AA to 9000\\AA for the two new systems, as well as for a comparison white dwarf-main sequence red dwarf system, GJ 283 AB. Using model grids available in the literature, we estimate the cooling age as well as temperature, surface gravity, mass, progenitor mass and {\\it total} lifetimes of the white dwarfs. The results indicate that the two new systems are probably ancient thick disk objects with ages of at least 6-9 Gyr. We also conduct searches of red dwarf and white dwarf compendia from SDSS data and the L{\\'e}pine Shara Proper Motion (LSPM) catalog for additional common proper motion white dwarf-red subdwarf systems. Only seven new candidate systems are found, which indicates the rarity of these systems.

  7. Final Independent External Peer Review Report for the White Oak Bayou Federal Flood Damage

    E-Print Network [OSTI]

    US Army Corps of Engineers

    Final Independent External Peer Review Report for the White Oak Bayou Federal Flood Damage Independent External Peer Review Report for the White Oak Bayou Federal Flood Damage Reduction Plan PEER REVIEW REPORT for the White Oak Bayou Federal Flood Damage Reduction Plan EXECUTIVE SUMMARY White

  8. Race, Class, and Whiteness in Gifted and Talented Identification: A Case Study

    E-Print Network [OSTI]

    Barlow, Kathleen; Dunbar, Elaine

    2010-01-01

    G. , & Eaton, S. (1996). Dismantling desegregation: Theresistant to change. Dismantling underlying white property

  9. Classification of Sunspot Groups Using SOHO/MDI Magnetogram and White-Light

    E-Print Network [OSTI]

    Wolfe, Patrick J.

    Classification of Sunspot Groups Using SOHO/MDI Magnetogram and White-Light Images Tuesday Data (or, what I currently have available) · 1038 white-light images from May 19, 1996 through December procedure will be developed using SOHO/MDI magnetogram and white- light images. SOHO/MDI white-light image

  10. The habitability and detection of Earth-like planets orbiting cool white L. Fossati1

    E-Print Network [OSTI]

    The habitability and detection of Earth-like planets orbiting cool white dwarfs. L. Fossati1 orbiting white dwarfs. As a white dwarf cools from 6000 K to 4000 K, a planet orbiting at 0.01 AU would with the persistence of complex life. Po- larisation due to a terrestrial planet in the CHZ of a cool white dwarf

  11. Effective theories and black hole production in warped compactificatio...

    Office of Scientific and Technical Information (OSTI)

    Effective theories and black hole production in warped compactifications Citation Details In-Document Search Title: Effective theories and black hole production in warped...

  12. Contribution of White Dwarfs to Cluster Masses

    E-Print Network [OSTI]

    Ted von Hippel

    1998-02-14

    I present a literature search through 31 July 1997 of white dwarfs (WDs) in open and globular clusters. There are 36 single WDs and 5 WDs in binaries known among 13 open clusters, and 340 single WDs and 11 WDs in binaries known among 11 globular clusters. From these data I have calculated WD mass fractions for four open clusters (the Pleiades, NGC 2168, NGC 3532, and the Hyades) and one globular cluster (NGC 6121). I develop a simple model of cluster evolution that incorporates stellar evolution but not dynamical evolution to interpret the WD mass fractions. I augment the results of my simple model with N-body simulations incorporating stellar evolution (Terlevich 1987; de la Feunte Marcos 1996; Vesperini & Heggie 1997). I find that even though these clusters undergo moderate to strong kinematical evolution the WD mass fraction is relatively insensitive to kinematical evolution. By comparing the cluster mass functions to that of the Galactic disk, and incorporating plausibility arguments for the mass function of the Galactic halo, I estimate the WD mass fraction in these two populations. I assume the Galactic disk is ~10 Gyrs old (Winget et al. 1987; Liebert, Dahn, & Monet 1988; Oswalt et al. 1996) and that the Galactic halo is ~12 Gyrs old (Reid 1997b; Gratton et al. 1997; Chaboyer et al. 1998), although the WD mass fraction is insensitive to age in this range. I find that the Galactic halo should contain 8 to 9% (alpha = -2.35) or perhaps as much as 15 to 17% (alpha = -2.0) of its stellar mass in the form of WDs. The Galactic disk WD mass fraction should be 6 to 7% (alpha = -2.35), consistent with the empirical estimates of 3 to 7% (Liebert, Dahn, & Monet 1988; Oswalt et al. 1996). (abridged)

  13. An electromagnetic black hole made of metamaterials

    E-Print Network [OSTI]

    Qiang Cheng; Tie Jun Cui; Wei Xiang Jiang; Ben Geng Cai

    2010-04-30

    Traditionally, a black hole is a region of space with huge gravitational field, which absorbs everything hitting it. In history, the black hole was first discussed by Laplace under the Newton mechanics, whose event horizon radius is the same as the Schwarzschild's solution of the Einstein's vacuum field equations. If all those objects having such an event horizon radius but different gravitational fields are called as black holes, then one can simulate certain properties of the black holes using electromagnetic fields and metamaterials due to the similar propagation behaviours of electromagnetic waves in curved space and in inhomogeneous metamaterials. In a recent theoretical work by Narimanov and Kildishev, an optical black hole has been proposed based on metamaterials, in which the theoretical analysis and numerical simulations showed that all electromagnetic waves hitting it are trapped and absorbed. Here we report the first experimental demonstration of such an electromagnetic black hole in the microwave frequencies. The proposed black hole is composed of non-resonant and resonant metamaterial structures, which can trap and absorb electromagnetic waves coming from all directions spirally inwards without any reflections due to the local control of electromagnetic fields and the event horizon corresponding to the device boundary. It is shown that the absorption rate can reach 99% in the microwave frequencies. We expect that the electromagnetic black hole could be used as the thermal emitting source and to harvest the solar light.

  14. Black holes cannot support conformal scalar hair

    E-Print Network [OSTI]

    T. Zannias

    1994-09-14

    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.

  15. Quantum Entropy of Charged Rotating Black Holes

    E-Print Network [OSTI]

    R. B. Mann

    1996-07-10

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

  16. Topological Black Holes in Quantum Gravity

    E-Print Network [OSTI]

    J. Kowalski-Glikman; D. Nowak-Szczepaniak

    2000-07-31

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

  17. Primordial black holes and asteroid danger

    E-Print Network [OSTI]

    Alexander Shatskiy

    2008-02-21

    Probability for a primordial black hole to invade the Kuiper belt was calculated. We showed that primordial black holes of certain masses can significantly change asteroids' orbits. These events may result in disasters, local for our solar system and global for the Earth (like the Tunguska meteorite). We also estimated how often such events occur.

  18. Stability of AdS black strings

    E-Print Network [OSTI]

    T. Delsate

    2008-08-14

    We review the recent developements in the stability problem and phase diagram for asymptotically locally $AdS$ black strings. First, we quickly review the case of locally flat black string before turning to the case of locally $AdS$ spacetimes.

  19. Canonical structure of 2D black holes

    E-Print Network [OSTI]

    Navarro-Salas, J; Talavera, C F

    1994-01-01

    We determine the canonical structure of two-dimensional black-hole solutions arising in $2D$ dilaton gravity. By choosing the Cauchy surface appropriately we find that the canonically conjugate variable to the black hole mass is given by the difference of local (Schwarzschild) time translations at right and left spatial infinities. This can be regarded as a generalization of Birkhoff's theorem.

  20. Fractal Statistics and Quantum Black Hole Entropy

    E-Print Network [OSTI]

    Wellington da Cruz

    2000-11-18

    Simple considerations about the fractal characteristic of the quantum-mechanical path give us the opportunity to derive the quantum black hole entropy in connection with the concept of fractal statistics. We show the geometrical origin of the numerical factor of four of the quantum black hole entropy expression and the statistics weight appears as a counting of the quanta of geometry.

  1. Can Superconducting Cosmic Strings Piercing Seed Black Holes Generate Supermassive Black Holes in the Early Universe?

    E-Print Network [OSTI]

    Lake, Matthew J

    2015-01-01

    The discovery of a large number of supermassive black holes at redshifts $z> 6$, when the Universe was only nine hundred million years old, has raised the fundamental question of how such massive compact objects could form in a (cosmologically) short time interval. Each of the proposed standard scenarios for black hole formation, involving rapid accretion of seed black holes, or black hole mergers, faces severe theoretical difficulties in explaining the short time formation of supermassive objects. In the present Letter, we propose an alternative scenario for the formation of supermassive black holes in the early Universe in which energy transfer from superconducting cosmic strings, piercing small seed black holes, is the main physical process leading to rapid mass increase. The increase in mass of a primordial seed black hole pierced by two antipodal strings is estimated and it is shown that this increases linearly in time. Due to the high energy transfer rate from the cosmic strings, we find that supermassi...

  2. Engine lubrication circuit including two pumps

    DOE Patents [OSTI]

    Lane, William H.

    2006-10-03

    A lubrication pump coupled to the engine is sized such that the it can supply the engine with a predetermined flow volume as soon as the engine reaches a peak torque engine speed. In engines that operate predominately at speeds above the peak torque engine speed, the lubrication pump is often producing lubrication fluid in excess of the predetermined flow volume that is bypassed back to a lubrication fluid source. This arguably results in wasted power. In order to more efficiently lubricate an engine, a lubrication circuit includes a lubrication pump and a variable delivery pump. The lubrication pump is operably coupled to the engine, and the variable delivery pump is in communication with a pump output controller that is operable to vary a lubrication fluid output from the variable delivery pump as a function of at least one of engine speed and lubrication flow volume or system pressure. Thus, the lubrication pump can be sized to produce the predetermined flow volume at a speed range at which the engine predominately operates while the variable delivery pump can supplement lubrication fluid delivery from the lubrication pump at engine speeds below the predominant engine speed range.

  3. Class Transitions in Black Holes

    E-Print Network [OSTI]

    Sandip K. Chakrabarti

    2005-01-14

    A black hole spectrum is known to change from the hard state to the soft state when the energy spectral index $\\alpha$ ($F_E \\propto E^{-\\alpha}$) in, say, 2-20 keV range changes from $\\alpha \\sim 0.5$ to $\\sim 1.5$. However, this `classical' definition which characterizes black holes like Cyg X-1, becomes less useful for many objects such as GRS 1915+105 in which the spectral slope is seen to vary from one to the other in a matter of seconds and depending on whether or not winds form, the spectral slope also changes. The light curves and the colour-colour diagrams may look completely different on different days depending on the frequency and mode of switching from one spectral state to the other. Though RXTE observations have yielded wealth of information on such `variability classes' in GRS 1915+105, very rarely one has been able to observe how the object goes from one class to the other. In the present review, we discuss possible origins of the class transition and present several examples of such transitions. In this context, we use mostly the results of the Indian X-ray Astronomy Experiment (IXAE) which observed GRS 1915+105 more regularly.

  4. Nonthermal correction to black hole spectroscopy

    E-Print Network [OSTI]

    Wen-Yu Wen

    2014-11-14

    Area spectrum of black holes have been obtained via various methods such as quasinormal modes, adiabatic invariance and angular momentum. Among those methods, calculations were done by assuming black holes in thermal equilibrium. Nevertheless, black holes in the asymptotically flat space usually have negative specific heat and therefore tend to stay away from thermal equilibrium. Even for those black holes with positive specific heat, temperature may still not be well defined in the process of radiation, due to the back reaction of decreasing mass. Respect to these facts, it is very likely that Hawking radiation is nonthermal and the area spectrum is no longer equidistant. In this note, we would like to illustrate how the area spectrum of black holes is corrected by this nonthermal effect.

  5. Evidence for the Black Hole Event Horizon

    E-Print Network [OSTI]

    Ramesh Narayan

    2003-10-23

    Astronomers have discovered many candidate black holes in X-ray binaries and in the nuclei of galaxies. The candidate objects are too massive to be neutron stars, and for this reason they are considered to be black holes. While the evidence based on mass is certainly strong, there is no proof yet that any of the objects possesses the defining characteristic of a black hole, namely an event horizon. Type I X-ray bursts, which are the result of thermonuclear explosions when gas accretes onto the surface of a compact star, may provide important evidence in this regard. Type I bursts are commonly observed in accreting neutron stars, which have surfaces, but have never been seen in accreting black hole candidates. It is argued that the lack of bursts in black hole candidates is compelling evidence that these objects do not have surfaces. The objects must therefore possess event horizons.

  6. Advancement of High Temperature Black Liquor Gasification Technology

    SciTech Connect (OSTI)

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

    2008-03-31

    Weyerhaeuser operates the world's only commercial high-temperature black liquor gasifier at its pulp mill in New Bern, NC. The unit was started-up in December 1996 and currently processes about 15% of the mill's black liquor. Weyerhaeuser, Chemrec AB (the gasifier technology developer), and the U.S. Department of Energy recognized that the long-term, continuous operation of the New Bern gasifier offered a unique opportunity to advance the state of high temperature black liquor gasification toward the commercial-scale pressurized O2-blown gasification technology needed as a foundation for the Forest Products Bio-Refinery of the future. Weyerhaeuser along with its subcontracting partners submitted a proposal in response to the 2004 joint USDOE and USDA solicitation - 'Biomass Research and Development Initiative'. The Weyerhaeuser project 'Advancement of High Temperature Black Liquor Gasification' was awarded USDOE Cooperative Agreement DE-FC26-04NT42259 in November 2004. The overall goal of the DOE sponsored project was to utilize the Chemrec{trademark} black liquor gasification facility at New Bern as a test bed for advancing the development status of molten phase black liquor gasification. In particular, project tasks were directed at improvements to process performance and reliability. The effort featured the development and validation of advanced CFD modeling tools and the application of these tools to direct burner technology modifications. The project also focused on gaining a fundamental understanding and developing practical solutions to address condensate and green liquor scaling issues, and process integration issues related to gasifier dregs and product gas scrubbing. The Project was conducted in two phases with a review point between the phases. Weyerhaeuser pulled together a team of collaborators to undertake these tasks. Chemrec AB, the technology supplier, was intimately involved in most tasks, and focused primarily on the design, specification and procurement of facility upgrades. Chemrec AB is also operating a pressurized, O2-blown gasifier pilot facility in Piteaa, Sweden. There was an exchange of knowledge with the pressurized projects including utilization of the experimental results from facilities in Piteaa, Sweden. Resources at the Georgia Tech Research Corporation (GTRC, a.k.a., the Institute of Paper Science and Technology) were employed primarily to conduct the fundamental investigations on scaling and plugging mechanisms and characterization of green liquor dregs. The project also tapped GTRC expertise in the development of the critical underlying black liquor gasification rate subroutines employed in the CFD code. The actual CFD code development and application was undertaken by Process Simulation, Ltd (PSL) and Simulent, Ltd. PSL focused on the overall integrated gasifier CFD code, while Simulent focused on modeling the black liquor nozzle and description of the black liquor spray. For nozzle development and testing Chemrec collaborated with ETC (Energy Technology Centre) in Piteae utilizing their test facility for nozzle spray investigation. GTI (Gas Technology Institute), Des Plains, IL supported the team with advanced gas analysis equipment during the gasifier test period in June 2005.

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

    SciTech Connect (OSTI)

    Barrett, Tate

    2014-07-01

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

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

    SciTech Connect (OSTI)

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

    2010-01-15

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

  9. A COMPREHENSIVE SPECTROSCOPIC ANALYSIS OF DB WHITE DWARFS

    SciTech Connect (OSTI)

    Bergeron, P.; Wesemael, F.; Dufour, Pierre; Beauchamp, A.; Hunter, C.; Gianninas, A.; Limoges, M.-M.; Dufour, Patrick; Fontaine, G. [Departement de Physique, Universite de Montreal, C.P. 6128, Succ. Centre-Ville, Montreal, QC H3C 3J7 (Canada); Saffer, Rex A. [Strayer University, 234 Mall Boulevard, Suite G-50, King of Prussia, PA 19406 (United States); Ruiz, M. T. [Departamento de Astronomia, Universidad de Chile, Casilla 36-D, Santiago (Chile); Liebert, James, E-mail: bergeron@astro.umontreal.ca, E-mail: wesemael@astro.umontreal.ca, E-mail: gianninas@astro.umontreal.ca, E-mail: limoges@astro.umontreal.ca, E-mail: dufourpa@astro.umontreal.ca, E-mail: fontaine@astro.umontreal.ca, E-mail: alain.beauchamp@fti-ibis.com, E-mail: chris.hunter@yale.edu, E-mail: rex.saffer@strayer.edu, E-mail: mtruiz@das.uchile.cl [Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States)

    2011-08-10

    We present a detailed analysis of 108 helium-line (DB) white dwarfs based on model atmosphere fits to high signal-to-noise optical spectroscopy. We derive a mean mass of 0.67 M{sub sun} for our sample, with a dispersion of only 0.09 M{sub sun}. White dwarfs also showing hydrogen lines, the DBA stars, comprise 44% of our sample, and their mass distribution appears similar to that of DB stars. As in our previous investigation, we find no evidence for the existence of low-mass (M < 0.5 M{sub sun}) DB white dwarfs. We derive a luminosity function based on a subset of DB white dwarfs identified in the Palomar-Green Survey. We show that 20% of all white dwarfs in the temperature range of interest are DB stars, although the fraction drops to half this value above T{sub eff} {approx} 20,000 K. We also show that the persistence of DB stars with no hydrogen features at low temperatures is difficult to reconcile with a scenario involving accretion from the interstellar medium, often invoked to account for the observed hydrogen abundances in DBA stars. We present evidence for the existence of two different evolutionary channels that produce DB white dwarfs: the standard model where DA stars are transformed into DB stars through the convective dilution of a thin hydrogen layer and a second channel where DB stars retain a helium atmosphere throughout their evolution. We finally demonstrate that the instability strip of pulsating V777 Her white dwarfs contains no non-variables, if the hydrogen content of these stars is properly accounted for.

  10. Mass and Angular Momentum of Black Holes: An Overlooked Effect of General Relativity Applied to the Galactic Center Black Hole Sgr A*

    E-Print Network [OSTI]

    B. Aschenbach

    2006-03-08

    I report the discovery of a new effect of General Relativity which is important to understand very rapidly rotating (Kerr) black holes. The orbital velocity of a test particle is no longer a monotonic function of the orbit radius when the spin of the black hole is >0.9953, but displays a local minimum-maximum structure for radii smaller than 1.8 gravitational radii. There the rate of change of the orbital velocity per radius unit equals the radial epicyclic frequency and is exactly one third of the polar epicyclic frequency, suggesting a 3:1 resonant oscillatory motion of the particle. If associated with the observed quasi-periods - including the most recent 2005/2006 data - the mass of the supermassive black hole Sgr A* in the centre of the our Galaxy is determined to 3.3 million solar masses and the spin is 0.99616.

  11. July 2014, IDC #250102 WHITE PAPER

    E-Print Network [OSTI]

    Greenberg, Albert

    (capex) as well as operational expenses (opex). Many organizations are turning to third parties of using a third-party services firm for hosted application management include shifting costs from capex

  12. Ionic liquids, electrolyte solutions including the ionic liquids, and energy storage devices including the ionic liquids

    DOE Patents [OSTI]

    Gering, Kevin L.; Harrup, Mason K.; Rollins, Harry W.

    2015-12-08

    An ionic liquid including a phosphazene compound that has a plurality of phosphorus-nitrogen units and at least one pendant group bonded to each phosphorus atom of the plurality of phosphorus-nitrogen units. One pendant group of the at least one pendant group comprises a positively charged pendant group. Additional embodiments of ionic liquids are disclosed, as are electrolyte solutions and energy storage devices including the embodiments of the ionic liquid.

  13. Black Hole Spectral States and Physical Connections

    E-Print Network [OSTI]

    John A. Tomsick

    2005-09-06

    The dramatic changes seen in the X-ray spectral and timing properties of accreting black hole candidates (BHCs) provide important clues about the accretion and jet formation processes that occur in these systems. Dividing the different source behaviors into spectral states provides a framework for studying BHCs. To date, there have been three main classification schemes with Luminosity-based, Component-based, or Transition-based criteria. The canonical, Luminosity-based criteria and physical models that are based on this concept do not provide clear explanations for several phenomena, including hysteresis of spectral states and the presence of jets. I discuss the re-definitions of states, focusing on an application of the Component-based states to more than 400 RXTE observations of the recurrent BHC 4U 1630-47. We compare the X-ray properties for the recent 2002-2004 outburst to those of an earlier (1998) outburst, during which radio jets were observed. The results suggest a connection between hysteresis of states and major jet ejections, and it is possible that both of these are related to the evolution of the inner radius of the optically thick accretion disk.

  14. White phosphorus pits focused feasibility study final July 2007.

    SciTech Connect (OSTI)

    Davis, B.; Martino, L.

    2007-08-21

    The White Phosphorus Burning Pits (WPP) Area of Concern (AOC) is a site of about 5.5 acres (2.2 ha) located in the J-Field Study Area, in the Edgewood Area of Aberdeen Proving Ground (APG), Maryland (Figure 1.1). Considerable information about the WPP exists as a result of efforts to characterize the hazards associated with J-Field. Contamination in the J-Field Study Area was first detected during an environmental survey of the APG Edgewood Area conducted in 1977 and 1978 (Nemeth et al. 1983) by the U.S. Army Toxic and Hazardous Materials Agency (USATHAMA; predecessor to the U.S. Army Environmental Center). As part of a subsequent USATHAMA environmental survey, 11 wells were installed and sampled at J-Field (three of them at the WPP) (Nemeth 1989). Contamination was also detected in 1983 during a munitions disposal survey conducted by Princeton Aqua Science (1984). The Princeton Aqua Science investigation involved installing and sampling nine wells (four at the WPP) and collecting and analyzing surficial and deep composite soil samples (including samples from the WPP area). In 1986, the U.S. Environmental Protection Agency (EPA) issued a Resource Conservation and Recovery Act (RCRA) Permit (MD3-21-002-1355) requiring a post-wide RCRA Facility Assessment (RFA) and a hydrogeologic assessment of J-Field. In 1987, the U.S. Geological Survey (USGS) began a two-phase hydrogeologic assessment in which data were collected to model groundwater flow at J-Field. Soil-gas investigations were conducted, several well clusters were installed (four at the WPP), a groundwater flow model was developed, and groundwater and surface water monitoring programs were established that continue today. The results of the USGS study were published by Hughes (1993).

  15. Out of the white hole: a holographic origin for the Big Bang

    SciTech Connect (OSTI)

    Pourhasan, Razieh; Afshordi, Niayesh; Mann, Robert B. E-mail: nafshordi@pitp.ca

    2014-04-01

    While most of the singularities of General Relativity are expected to be safely hidden behind event horizons by the cosmic censorship conjecture, we happen to live in the causal future of the classical Big Bang singularity, whose resolution constitutes the active field of early universe cosmology. Could the Big Bang be also hidden behind a causal horizon, making us immune to the decadent impacts of a naked singularity? We describe a braneworld description of cosmology with both 4d induced and 5D bulk gravity (otherwise known as Dvali-Gabadadze-Porati, or DGP model), which exhibits this feature: the universe emerges as a spherical 3-brane out of the formation of a 5D Schwarzschild black hole. In particular, we show that a pressure singularity of the holographic fluid, discovered earlier, happens inside the white hole horizon, and thus need not be real or imply any pathology. Furthermore, we outline a novel mechanism through which any thermal atmosphere for the brane, with comoving temperature of ?20% of the 5D Planck mass can induce scale-invariant primordial curvature perturbations on the brane, circumventing the need for a separate process (such as cosmic inflation) to explain current cosmological observations. Finally, we note that 5D space-time is asymptotically flat, and thus potentially allows an S-matrix or (after minor modifications) an AdS/CFT description of the cosmological Big Bang.

  16. The White Dwarf Cooling Sequence of NGC6397

    E-Print Network [OSTI]

    Brad M. S. Hansen; Jay Anderson; James Brewer; Aaron Dotter; Greg. G. Fahlman; Jarrod Hurley; Jason Kalirai; Ivan King; David Reitzel; Harvey B. Richer; R. Michael Rich; Michael M. Shara; Peter B. Stetson

    2007-02-20

    We present the results of a deep Hubble Space Telescope (HST) exposure of the nearby globular cluster NGC6397, focussing attention on the cluster's white dwarf cooling sequence. This sequence is shown to extend over 5 magnitudes in depth, with an apparent cutoff at magnitude F814W=27.6. We demonstrate, using both artificial star tests and the detectability of background galaxies at fainter magnitudes, that the cutoff is real and represents the truncation of the white dwarf luminosity function in this cluster. We perform a detailed comparison between cooling models and the observed distribution of white dwarfs in colour and magnitude, taking into account uncertainties in distance, extinction, white dwarf mass, progenitor lifetimes, binarity and cooling model uncertainties. After marginalising over these variables, we obtain values for the cluster distance modulus and age of \\mu_0 = 12.02 \\pm 0.06 and T_c = 11.47 \\pm 0.47Gyr (95% confidence limits). Our inferred distance and white dwarf initial-final mass relations are in good agreement with other independent determinations, and the cluster age is consistent with, but more precise than, prior determinations made using the main sequence turnoff method. In particular, within the context of the currently accepted \\Lambda CDM cosmological model, this age places the formation of NGC6397 at a redshift z=3, at a time when the cosmological star formation rate was approaching its peak.

  17. The White Dwarf Cooling Sequence of NGC6397

    E-Print Network [OSTI]

    Hansen, B M S; Brewer, J; Dotter, A; Fahlman, G G; Hurley, J; King, I; Reitzel, David B; Richer, H B; Rich, R M; Shara, M M; Stetson, P B; Hansen, Brad M. S.; Anderson, Jay; Brewer, James; Dotter, Aaron; Fahlman, Greg. G.; Hurley, Jarrod; King, Ivan; Reitzel, David; Richer, Harvey B.; Shara, Michael M.; Stetson, Peter B.

    2007-01-01

    We present the results of a deep Hubble Space Telescope (HST) exposure of the nearby globular cluster NGC6397, focussing attention on the cluster's white dwarf cooling sequence. This sequence is shown to extend over 5 magnitudes in depth, with an apparent cutoff at magnitude F814W=27.6. We demonstrate, using both artificial star tests and the detectability of background galaxies at fainter magnitudes, that the cutoff is real and represents the truncation of the white dwarf luminosity function in this cluster. We perform a detailed comparison between cooling models and the observed distribution of white dwarfs in colour and magnitude, taking into account uncertainties in distance, extinction, white dwarf mass, progenitor lifetimes, binarity and cooling model uncertainties. After marginalising over these variables, we obtain values for the cluster distance modulus and age of \\mu_0 = 12.02 \\pm 0.06 and T_c = 11.47 \\pm 0.47Gyr (95% confidence limits). Our inferred distance and white dwarf initial-final mass relat...

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

    E-Print Network [OSTI]

    Beaucage, Gregory

    -ray scattering (SAXS) study of a conductive grade of carbon black and carbon black­polymer composites and a power-law scaling of polydispersity. One use of conductive black­polyethylene composites is in circuit(methyl methacrylate); carbon black; filler; composite; conductivity; percolation INTRODUCTION The morphology

  19. Report on the WORKSHOP ON COMMERCIALIZATION OF BLACK LIQUOR

    E-Print Network [OSTI]

    .3. Gasifier Supplier Perspectives 11 Black Liquor Gasifier Suppliers 12 Biomass Gasifier Suppliers 13 5

  20. Testing black hole candidates with electromagnetic radiation

    E-Print Network [OSTI]

    Bambi, Cosimo

    2015-01-01

    Astrophysical black hole candidates are thought to be the Kerr black holes of general relativity, but there is currently no direct observational evidence that the spacetime geometry around these objects is described by the Kerr solution. The study of the properties of the electromagnetic radiation emitted by gas or stars orbiting these objects can potentially test the Kerr black hole hypothesis. In this paper, I review the state of the art of this research field, describing the possible approaches to test the Kerr metric with current and future observational facilities and discussing current constraints.

  1. Quasinormal Modes of Dirty Black Holes

    E-Print Network [OSTI]

    P. T. Leung; Y. T. Liu; W. -M. Suen; C. Y. Tam; K. Young

    1999-03-08

    Quasinormal mode (QNM) gravitational radiation from black holes is expected to be observed in a few years. A perturbative formula is derived for the shifts in both the real and the imaginary part of the QNM frequencies away from those of an idealized isolated black hole. The formulation provides a tool for understanding how the astrophysical environment surrounding a black hole, e.g., a massive accretion disk, affects the QNM spectrum of gravitational waves. We show, in a simple model, that the perturbed QNM spectrum can have interesting features.

  2. Black Hole Thermodynamics and Statistical Mechanics

    E-Print Network [OSTI]

    Steven Carlip

    2008-07-28

    We have known for more than thirty years that black holes behave as thermodynamic systems, radiating as black bodies with characteristic temperatures and entropies. This behavior is not only interesting in its own right; it could also, through a statistical mechanical description, cast light on some of the deep problems of quantizing gravity. In these lectures, I review what we currently know about black hole thermodynamics and statistical mechanics, suggest a rather speculative "universal" characterization of the underlying states, and describe some key open questions.

  3. Some remarks on black hole thermodynamics

    E-Print Network [OSTI]

    R. Y. Chiao

    2011-02-04

    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.

  4. Thermodynamics of Dyonic Lifshitz Black Holes

    E-Print Network [OSTI]

    Tobias Zingg

    2011-07-15

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

  5. Testing the Kerr black hole hypothesis

    E-Print Network [OSTI]

    Cosimo Bambi

    2011-10-13

    It is thought that the final product of the gravitational collapse is a Kerr black hole and astronomers have discovered several good astrophysical candidates. While there is some indirect evidence suggesting that the latter have an event horizon, and therefore that they are black holes, a proof that the space-time around these objects is described by the Kerr geometry is still lacking. Recently, there has been an increasing interest in the possibility of testing the Kerr black hole hypothesis with present and future experiments. In this paper, I briefly review the state of the art of the field, focussing on some recent results and work in progress.

  6. Scalar Perturbations of Charged Dilaton Black Holes

    E-Print Network [OSTI]

    Sharmanthie Fernando; Keith Arnold

    2015-08-01

    We have studied the scalar perturbation of static charged dilaton black holes in 3+1 dimensions. The black hole considered here is a solution to the low-energy string theory in 3+1 dimensions. The quasinormal modes for the scalar perturbations are calculated using the third order WKB method. The dilaton coupling constant has a considerable effect on the values of quasi normal modes. It is also observed that there is a linear relation between the quasi normal modes and the temperature for large black holes.

  7. Energy density bounds for black strings

    E-Print Network [OSTI]

    Shinya Tomizawa

    2005-06-07

    The conserved charge called Y-ADM mass density associated with asymptotically translational Killing-Yano tensor gives us an appropriate physical meaning about the energy density of $p$ brane spacetimes or black strings. We investigated the positivity of energy density in black string spacetimes, using the spinorial technique introduced by Witten. Recently, the positivity of Y-ADM mass density in p brane spacetimes was discussed. In this paper, we will extend this discussion to the transversely asymptotically flat black string spacetimes containing an apparent horizon. We will give the sufficient conditions for the Y-ADM mass density to become positive in such spacetimes.

  8. GRMHD formulation of highly super-Chandrasekhar rotating magnetised white dwarfs: Stable configurations of non-spherical white dwarfs

    E-Print Network [OSTI]

    Sathyawageeswar Subramanian; Banibrata Mukhopadhyay

    2015-10-01

    Here we extend the exploration of significantly super-Chandrasekhar magnetised white dwarfs by numerically computing axisymmetric stationary equilibria of differentially rotating magnetised polytropic compact stars in general relativity (GR), within the ideal magnetohydrodynamic regime. We use a general relativistic magnetohydrodynamic (GRMHD) framework that describes rotating and magnetised axisymmetric white dwarfs, choosing appropriate rotation laws and magnetic field profiles (toroidal and poloidal). The numerical procedure for finding solutions in this framework uses the 3+1 formalism of numerical relativity, implemented in the open source XNS code. We construct equilibrium sequences by varying different physical quantities in turn, and highlight the plausible existence of super-Chandrasekhar white dwarfs, with masses in the range of 2-3 solar mass, with central (deep interior) magnetic fields of the order of $10^{14}$ Gauss and differential rotation with surface time periods of about 1-10 seconds. We note that such white dwarfs are candidates for the progenitors of peculiar, overluminous type Ia supernovae, to which observational evidence ascribes mass in the range 2.1-2.8 solar mass. We also present some interesting results related to the structure of such white dwarfs, especially the existence of polar hollows in special cases.

  9. DOUGLAS R. WHITE Societal Research Archives System

    E-Print Network [OSTI]

    White, Douglas R.

    all of the steps in comparative research, from sample selection and data retrieval to correlation. NAROLL and R. COHEN (eds.), Handbook of method in cultural anthropology, New York, Natural History Press information 7(3), pp-79-94. #12;80 SCOPE OF MATERIALS INCLUDED IN SRAS ~ ~ As of fall, 1967, the comparative

  10. Constraining the neutrino magnetic dipole moment from white dwarf pulsations

    SciTech Connect (OSTI)

    Córsico, A.H.; Althaus, L.G.; García-Berro, E. E-mail: althaus@fcaglp.unlp.edu.ar E-mail: kepler@if.ufrgs.br

    2014-08-01

    Pulsating white dwarf stars can be used as astrophysical laboratories to constrain the properties of weakly interacting particles. Comparing the cooling rates of these stars with the expected values from theoretical models allows us to search for additional sources of cooling due to the emission of axions, neutralinos, or neutrinos with magnetic dipole moment. In this work, we derive an upper bound to the neutrino magnetic dipole moment (?{sub ?}) using an estimate of the rate of period change of the pulsating DB white dwarf star PG 1351+489. We employ state-of-the-art evolutionary and pulsational codes which allow us to perform a detailed asteroseismological period fit based on fully DB white dwarf evolutionary sequences. Plasmon neutrino emission is the dominant cooling mechanism for this class of hot pulsating white dwarfs, and so it is the main contributor to the rate of change of period with time (Pidot) for the DBV class. Thus, the inclusion of an anomalous neutrino emission through a non-vanishing magnetic dipole moment in these sequences notably influences the evolutionary timescales, and also the expected pulsational properties of the DBV stars. By comparing the theoretical Pidot value with the rate of change of period with time of PG 1351+489, we assess the possible existence of additional cooling by neutrinos with magnetic dipole moment. Our models suggest the existence of some additional cooling in this pulsating DB white dwarf, consistent with a non-zero magnetic dipole moment with an upper limit of ?{sub ?} ?< 10{sup -11} ?{sub B}. This bound is somewhat less restrictive than, but still compatible with, other limits inferred from the white dwarf luminosity function or from the color-magnitude diagram of the Globular cluster M5. Further improvements of the measurement of the rate of period change of the dominant pulsation mode of PG 1351+489 will be necessary to confirm our bound.

  11. Thermodynamics and evaporation of the noncommutative black hole

    E-Print Network [OSTI]

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

    2007-01-21

    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.

  12. Energy of 4-Dimensional Black Hole, etc

    E-Print Network [OSTI]

    Dmitriy Palatnik

    2011-07-18

    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.

  13. Horizon Operator Approach to Black Hole Quantization

    E-Print Network [OSTI]

    G. 't Hooft

    1994-02-21

    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\

  14. Evidence for the Black Hole Event Horizon

    E-Print Network [OSTI]

    Ramesh Narayan; Jeremy S. Heyl

    2002-04-26

    Roughly a dozen X-ray binaries are presently known in which the compact accreting primary stars are too massive to be neutron stars. These primaries are identified as black holes, though there is as yet no definite proof that any of the candidate black holes actually possesses an event horizon. We discuss how Type I X-ray bursts may be used to verify the presence of the event horizon in these objects. Type I bursts are caused by thermonuclear explosions when gas accretes onto a compact star. The bursts are commonly seen in many neutron star X-ray binaries, but they have never been seen in any black hole X-ray binary. Our model calculations indicate that black hole candidates ought to burst frequently if they have surfaces. Based on this, we argue that the lack of bursts constitutes strong evidence for the presence of event horizons in these objects.

  15. CHARYBDIS: A Black hole event generator.

    E-Print Network [OSTI]

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

    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...

  16. Spacetime constraints on accreting black holes

    SciTech Connect (OSTI)

    Garofalo, David [Jet Propulsion Laboratory, California Institute of Technology, Pasadena California 91109 (United States)

    2009-06-15

    We study the spin dependence of accretion onto rotating Kerr black holes using analytic techniques. In its linear regime, angular momentum transport in MHD turbulent accretion flow involves the generation of radial magnetic field connecting plasma in a differentially rotating flow. We take a first principles approach, highlighting the constraint that limits the generation and amplification of radial magnetic fields, stemming from the transfer of energy from mechanical to magnetic form. Because the energy transferred in magnetic form is ultimately constrained by gravitational potential energy or Killing energy, the spin dependence of the latter allows us to derive spin-dependent constraints on the success of the accreting plasma to expel its angular momentum. We find an inverse relationship between this ability and black hole spin. If this radial magnetic field generation forms the basis for angular momentum transfer in accretion flows, accretion rates involving Kerr black holes are expected to be lower as the black hole spin increases in the prograde sense.

  17. Black Hills Energy- Solar Power Program

    Broader source: Energy.gov [DOE]

    All incentive payments are subject to the availability of funds and a pre-installation site inspection. Black Hills Energy has established participation caps for each tier. The status of funding ...

  18. Radionuclide Inventory Distribution Project Data Evaluation and Verification White Paper

    SciTech Connect (OSTI)

    NSTec Environmental Restoration

    2010-05-17

    Testing of nuclear explosives caused widespread contamination of surface soils on the Nevada Test Site (NTS). Atmospheric tests produced the majority of this contamination. The Radionuclide Inventory and Distribution Program (RIDP) was developed to determine distribution and total inventory of radionuclides in surface soils at the NTS to evaluate areas that may present long-term health hazards. The RIDP achieved this objective with aerial radiological surveys, soil sample results, and in situ gamma spectroscopy. This white paper presents the justification to support the use of RIDP data as a guide for future evaluation and to support closure of Soils Sub-Project sites under the purview of the Federal Facility Agreement and Consent Order. Use of the RIDP data as part of the Data Quality Objective process is expected to provide considerable cost savings and accelerate site closures. The following steps were completed: - Summarize the RIDP data set and evaluate the quality of the data. - Determine the current uses of the RIDP data and cautions associated with its use. - Provide recommendations for enhancing data use through field verification or other methods. The data quality is sufficient to utilize RIDP data during the planning process for site investigation and closure. Project planning activities may include estimating 25-millirem per industrial access year dose rate boundaries, optimizing characterization efforts, projecting final end states, and planning remedial actions. In addition, RIDP data may be used to identify specific radionuclide distributions, and augment other non-radionuclide dose rate data. Finally, the RIDP data can be used to estimate internal and external dose rates. The data quality is sufficient to utilize RIDP data during the planning process for site investigation and closure. Project planning activities may include estimating 25-millirem per industrial access year dose rate boundaries, optimizing characterization efforts, projecting final end states, and planning remedial actions. In addition, RIDP data may be used to identify specific radionuclide distributions, and augment other non-radionuclide dose rate data. Finally, the RIDP data can be used to estimate internal and external dose rates.

  19. White dwarfs as physics laboratories: the case of axions

    E-Print Network [OSTI]

    J. Isern; L. Althaus; S. Catalan; A. Corsico; E. Garcia-Berro; M. Salaris; S. Torres

    2012-04-16

    White dwarfs are almost completely degenerate objects that cannot obtain energy from thermonuclear sources, so their evolution is just a gravothermal cooling process. Recent improvements in the accuracy and precision of the luminosity function and in pulsational data of variable white dwarfs suggest that they are cooling faster than expected from conventional theory. In this contribution we show that the inclusion of an additional cooling term due to axions able to interact with electrons with a coupling constant g_ae ~(2-7)x10^{-13} allows to fit better the observations.

  20. White paper updating conclusions of 1998 ILAW performance assessment

    SciTech Connect (OSTI)

    MANN, F.M.

    2000-05-11

    The purpose of this document is to provide a comparison of the estimated immobilized low-activity waste (LAW) disposal system performance against established performance objectives using the beat estimates for parameters and models to describe the system. The principal advances in knowledge since the last performance assessment (known as the 1998 ILAW PA [Mann 1998a]) have been in site specific information and data on the waste form performance for BNFL, Inc. relevant glass formulations. The white paper also estimates the maximum release rates for technetium and other key radionuclides and chemicals from the waste form. Finally, this white paper provides limited information on the impact of changes in waste form loading.

  1. Scientific Prospectus Figure 1. Proposed drill sites (white circles with black rims) and alternates (solid circles) for

    E-Print Network [OSTI]

    . (1985) Neogene equatorial Pacific seismic stratigraphy. Figure 4. A schematic of the equatorial sediment the model shown here and in Figure 5. TWTT = two-way traveltime. Figure 5. Tentative seismic stratigraphy was estimated from physical properties of sediments and the distance between seismic reflectors in profiles

  2. Black Moms and “White Motherhood Society”: African-American Middle-Class Mothers’ Perspectives on Work, Family and Identity

    E-Print Network [OSTI]

    Dow, Dawn

    2011-01-01

    Forthcoming. “Crossing Class Boundaries: Race, Siblings andKaufman, Peter. 2005. “Middle-Class Social Reproduction. ”Ethnicity, Gender, and Class. ” Journal of Marriage and

  3. Black and white BG1 copiers are available in the following locations: Jerome Library Serials Area Browne Popular Culture Library

    E-Print Network [OSTI]

    Moore, Paul A.

    and the Rec Center. Guest patrons may purchase a BG1Copy Card at the BG1 Account Management Center located, power the machine off, wait five seconds then power back on. The power button is located towards the back on the left side of the copier. Do not use the power button on the front of the machine. Please

  4. Family, friendship and the transition to secondary school: the experiences of black, minority ethnic and white children 

    E-Print Network [OSTI]

    Graham, Catherine; Hill, Malcolm

    Around the age of 11, nearly all Scottish children transfer from primary to secondary school. This will involve changes to the size, location, class structure, curriculum, ethos of school as well as markedly altering ...

  5. Classical and thermodynamic stability of black holes

    E-Print Network [OSTI]

    Monteiro, Ricardo

    2010-07-06

    Perturbations of the asymptotic charges . . . . . . . . . . . . . . . . 169 IV Conclusion 171 9 Conclusion and outlook 173 A Spectral numerical method 177 2 CONTENTS Part I Introduction 3 Chapter 1 Black holes Black holes are arguably the most interesting... to Newto- nian dynamics in the Solar system, and the indirect detection of gravitational waves from binary pulsars [1]. A crucial distinction from Newtonian gravity is that the “action-at-a-distance” is substituted by a built-in causality structure...

  6. Black Holes and Biophysical (Mem)-branes

    E-Print Network [OSTI]

    Jay Armas; Troels Harmark

    2014-11-26

    We argue that the effective theory describing the long-wavelength dynamics of black branes is the same effective theory that describes the dynamics of biophysical membranes. We improve the phase structure of higher-dimensional black rings by considering finite thickness corrections in this effective theory, showing a striking agreement between our analytical results and recent numerical constructions while simultaneously drawing a parallel between gravity and the effective theory of biophysical membranes.

  7. Fractionated Branes and Black Hole Interiors

    E-Print Network [OSTI]

    Emil J. Martinec

    2015-05-20

    Combining a variety of results in string theory and general relativity, a picture of the black hole interior is developed wherein spacetime caps off at an inner horizon, and the inter-horizon region is occupied by a Hagedorn gas of a very low tension state of fractionated branes. This picture leads to natural resolutions of a variety of puzzles concerning quantum black holes. Gravity Research Foundation 2015 Fourth Prize Award for Essays on Gravitation.

  8. GRMHD formulation of highly super-Chandrasekhar rotating magnetised white dwarfs: Stable configurations of non-spherical white dwarfs

    E-Print Network [OSTI]

    Subramanian, Sathyawageeswar

    2015-01-01

    Here we extend the exploration of significantly super-Chandrasekhar magnetised white dwarfs by numerically computing axisymmetric stationary equilibria of differentially rotating magnetised polytropic compact stars in general relativity (GR), within the ideal magnetohydrodynamic regime. We use a general relativistic magnetohydrodynamic (GRMHD) framework that describes rotating and magnetised axisymmetric white dwarfs, choosing appropriate rotation laws and magnetic field profiles (toroidal and poloidal). The numerical procedure for finding solutions in this framework uses the 3+1 formalism of numerical relativity, implemented in the open source XNS code. We construct equilibrium sequences by varying different physical quantities in turn, and highlight the plausible existence of super-Chandrasekhar white dwarfs, with masses in the range of 2-3 solar mass, with central (deep interior) magnetic fields of the order of $10^{14}$ Gauss and differential rotation with surface time periods of about 1-10 seconds. We no...

  9. Angular momentum exchange in white dwarf binaries accreting through direct impact

    SciTech Connect (OSTI)

    Sepinsky, J. F. [Department of Physics and Electrical Engineering, The University of Scranton, Scranton, PA 18510 (United States); Kalogera, V., E-mail: jeremy.sepinsky@scranton.edu, E-mail: vicky@northwestern.edu [Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA) and Department of Physics and Astronomy, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208 (United States)

    2014-04-20

    We examine the exchange of angular momentum between the component spins and the orbit in semi-detached double white dwarf binaries undergoing mass transfer through direct impact of the transfer stream. We approximate the stream as a series of discrete massive particles ejected in the ballistic limit at the inner Lagrangian point of the donor toward the accretor. This work improves upon similar earlier studies in a number of ways. First, we self-consistently calculate the total angular momentum of the orbit at all times. This includes changes in the orbital angular momentum during the ballistic trajectory of the ejected mass, as well as changes during the ejection/accretion due to the radial component of the particle's velocity. Second, we calculate the particle's ballistic trajectory for each system, which allows us to determine the precise position and velocity of the particle upon accretion. We can then include specific information about the radius of the accretor as well as the angle of impact. Finally, we ensure that the total angular momentum is conserved, which requires the donor star spin to vary self-consistently. With these improvements, we calculate the angular momentum change of the orbit and each binary component across the entire parameter space of direct impact double white dwarf binary systems. We find a significant decrease in the amount of angular momentum removed from the orbit during mass transfer, as well as cases where this process increases the angular momentum of the orbit at the expense of the spin angular momentum of the donor. We conclude that, unlike earlier claims in the literature, mass transfer through direct impact need not destabilize the binary and that the quantity and sign of the orbital angular momentum transfer depends on the binary properties, particularly the masses of the double white dwarf binary component stars. This stabilization may significantly impact the population synthesis calculations of the expected numbers of events/systems for which double white dwarfs may be a progenitor, e.g., Type Ia supernovae, Type.Ia supernovae, and AM CVn.

  10. Exploiting simultaneous observational constraints on mass and absorption to estimate the global direct radiative forcing of black carbon and brown carbon

    E-Print Network [OSTI]

    Schwarz, J. P.

    Atmospheric black carbon (BC) is a leading climate warming agent, yet uncertainties on the global direct radiative forcing (DRF) remain large. Here we expand a global model simulation (GEOS-Chem) of BC to include the ...

  11. A comprehensive program to develop correlations for physical properties of kraft black liquor. Final report

    SciTech Connect (OSTI)

    Fricke, A.L.; Zaman, A.A.

    1998-05-01

    The overall objective of the program was to develop correlations to predict physical properties within requirements of engineering precision from a knowledge of pulping conditions and of kraft black liquor composition, if possible. These correlations were to include those relating thermodynamic properties to pulping conditions and liquor composition. The basic premise upon which the research was based is the premise that black liquor behaves as a polymer solution. This premise has proven to be true, and has been used successfully in developing data reduction methods and in interpreting results. A three phase effort involving pulping, analysis of liquor composition, and measurement of liquor properties was conducted.

  12. Nanoscopy Reveals Metallic Black Phosphorus

    E-Print Network [OSTI]

    Abate, Yohannes; Zhen, Li; Cronin, Stephen B; Wang, Han; Babicheva, Viktoriia; Javani, Mohammad H; Stockman, Mark I

    2015-01-01

    Layered and two-dimensional (2D) materials such as graphene, boron nitride, transition metal dichalcogenides(TMDCs), and black phosphorus (BP) have intriguing fundamental physical properties and bear promise of numerous important applications in electronics and optics. Of them, BP is a novel 2D material that has been theoretically predicted to acquire plasmonic behavior for frequencies below ~0.4 eV when highly doped. The electronic properties of BP are unique due to an anisotropic structure, which could strongly influence collective electronic excitations. Advantages of BP as a material for nanoelectronics and nanooptics are due to the fact that, in contrast to metals, the free carrier density in it can be dynamically controlled by electrostatic gating, which has been demonstrated by its use in field-effect transistors. Despite all the interest that BP attracts, near-field and plasmonic properties of BP have not yet been investigated experimentally. Here we report the first observation of nanoscopic near-fie...

  13. Stay-Clean and Durable White Elastomeric Roof Coatings (ERCs...

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

    Dow Chemical developed high-performing white ERCs City Savings (m 2 year) Athens 2.8 Lyon 1.1 Istanbul 1.9 Dubai 2.7 Riyadh 2.2 In durability studies, Dow's ERCs adhered well to...

  14. Solar Radio Bursts and Space Weather Stephen M. White

    E-Print Network [OSTI]

    White, Stephen

    advantage of exceptionally clean radio spectra of such bursts acquired with the Green Bank Solar Radio Burst­effective disturbances probably originate: the layers where energy is released in solar flares, where energetic particlesSolar Radio Bursts and Space Weather Stephen M. White Dept. of Astronomy, University of Maryland

  15. White Blood Cell and Platelet Aggregation in Stenoses: A

    E-Print Network [OSTI]

    Petta, Jason

    always forms · Force = 4e-11 N (Bell, 1978) · Mass = 4.08e-13 kg (Shalak and Chien, 1987) ­ 1070 kg/m3White Blood Cell and Platelet Aggregation in Stenoses: A Computational Model Stephen H. Dao, Zhanke affect flow · Predict aggregation patterns and rates ­ Computer simulations · Model thrombosis mechanism

  16. The frequency of planetary debris around young white dwarfs

    E-Print Network [OSTI]

    Koester, Detlev; Farihi, Jay

    2014-01-01

    (Abridged) We present the results of the first unbiased survey for metal pollution among H-atmosphere (DA) white dwarfs with cooling ages of 20-200 Myr and 17000K 0.8 Msun is found to be currently accreting, which suggests a large fraction are double-degenerate mergers, and the merger discs do not commonly reform large planetesimals or otherwise pollute the remnant. We reconfirm our previous finding that two white dwarf Hyads are currently accreting rocky debris. At least 27%, and possibly up to ~50%, of all white dwarfs with cooling ages 20-200 Myr are accreting planetary debris. At Teff > 23000K, the luminosity of white dwarfs is likely sufficient to vaporize circumstellar dust, and hence no stars with strong metal-pollution are found. However, planetesimal disruption events should occur in this cooling age and Teff range as well, and likely result in short phases of high mass transfer rates. It appears that the formation of rocky planetary material is common around 2-3 Msun late B- and A-type stars.

  17. A White Book on Faculty of Information Technology, Mathematics and

    E-Print Network [OSTI]

    aspects have been the injection of new and green energy resources into the grid (such as wind, solar a definition inspired by IEC and SmartGrids ETP: "A Smart Grid is an electric power network that utilizes twoA White Book on Smart Grid Faculty of Information Technology, Mathematics and Electrical

  18. Future Grid: The Environment Future Grid Initiative White Paper

    E-Print Network [OSTI]

    Future Grid: The Environment Future Grid Initiative White Paper Power Systems Engineering Research Center Empowering Minds to Engineer the Future Electric Energy System #12;Future Grid: The Environment Prepared for the Project "The Future Grid to Enable Sustainable Energy Systems" Funded by the U

  19. White-Nose Syndrome (WNS) has caused catastrophic declines in

    E-Print Network [OSTI]

    White-Nose Syndrome (WNS) has caused catastrophic declines in hibernating bats in the United States Death Rate The impact of WNS is frightening! Up to 99% of bats in some WNS-infected populations die closures. Check with your state and federal agencies or a local chapter of the National Speleological

  20. White Papers Submitted to the Technology Innovation Program

    E-Print Network [OSTI]

    Magee, Joseph W.

    and complex systems, energy, ensuring future water supply, healthcare, manufacturing, nanomaterials competition planning process. This analysis provides some insight into the range of input TIP received through of the 590 authors and contributors of the first 275 white papers. Nonprofit, 54 Large Company, 36 Individual

  1. White Paper Conflicts of Interest and Academic Industry Relationships

    E-Print Network [OSTI]

    Mootha, Vamsi K.

    White Paper Conflicts of Interest and Academic Industry Relationships July 15, 2009 Jeffrey S are the HMS faculty and why might they want to interact with industry? The faculty of HMS are approximately 10 and expertise that can be deployed to enhance therapeutic discovery and development. Collaboration with industry

  2. Technology-Enabled Medicine Bryan White, Ph.D.

    E-Print Network [OSTI]

    Lee, Tonghun

    Technology-Enabled Medicine Bryan White, Ph.D. Director, Mayo-Illinois Alliance Clinic to develop new technologies that will transform the prac=ce of medicine:on-based medicine and point-of-care diagnos:cs Discovering new technologies and bringing them

  3. Carbon nanotube composites for photovoltaic devices White Paper

    E-Print Network [OSTI]

    Gruner, George

    in recent years. In particular interest are so called third generation devices, that involve polymersCarbon nanotube composites for photovoltaic devices White Paper Summary In a collaborative effort into charge separated sates. Preamble Novel photovoltaic and solar cell devices have gained prominence

  4. Organic Electronics and Photovoltaics CopyrightDaveWhite2008

    E-Print Network [OSTI]

    ENERGY Organic Electronics and Photovoltaics Objective CopyrightDaveWhite2008 Organic electronics and photovoltaic technology are reaching critical mass with the establishment of a U.S. consortium and the recent an inte- grated suite of measurement methods to tie the electrical and photovoltaic performance of organic

  5. Performance and Interoperability in Solar A. Abram White

    E-Print Network [OSTI]

    1 Performance and Interoperability in Solar A. Abram White abewhite@mac.com Senior Honors Thesis with applications that are able to adapt to our dynamics. Solar is a software infrastructure designed to deliver-aware devices envisioned by ubiquitous computing, Solar must exhibit both high performance and the ability

  6. Water Resources People and Issues GILBERT F. WHITE

    E-Print Network [OSTI]

    Ponce, V. Miguel

    natural resources and water and land. When I encountered a group in the geography departmentWater Resources People and Issues GILBERT F. WHITE by Martin Reuss #12;Interview with Gilbert F ever think about going anywhere else? 3 #12;Water Resources People and Issues A: No. We were all

  7. Electrophoretic Deposition of Highly Efficient Phosphors for White Solid State Lighting using near UV-Emitting LEDs /

    E-Print Network [OSTI]

    Choi, Jae Ik

    2014-01-01

    application in white light emitting diode,” J. Mater. Res. ,S.Y. Choi. “White light-emitting diodes of GaN-based Sr 2phosphor for white light-emitting diodes prepared by sol–gel

  8. Revisiting the axion bounds from the Galactic white dwarf luminosity function

    SciTech Connect (OSTI)

    Bertolami, M.M. Miller [Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, 85748, Garching (Germany); Melendez, B.E.; Althaus, L.G. [Instituto de Astrofísica de La Plata, UNLP-CONICET, Paseo del Bosque s/n, 1900 La Plata (Argentina); Isern, J., E-mail: marcelo@MPA-Garching.MPG.DE, E-mail: brenmele@gmail.com, E-mail: althaus@fcaglp.fcaglp.unlp.edu.ar, E-mail: isern@ieec.cat [Institut de Ciéncies de l'Espai (CSIC), Facultat de Ciéncies, Campus UAB, Torre C5-parell, 08193 Bellaterra (Spain)

    2014-10-01

    It has been shown that the shape of the luminosity function of white dwarfs (WDLF) is a powerful tool to check for the possible existence of DFSZ-axions, a proposed but not yet detected type of weakly interacting particles. With the aim of deriving new constraints on the axion mass, we compute in this paper new theoretical WDLFs on the basis of WD evolving models that incorporate the feedback of axions on the thermal structure of the white dwarf. We find that the impact of the axion emission into the neutrino emission can not be neglected at high luminosities M{sub  Bol}?< 8) and that the axion emission needs to be incorporated self-consistently into the evolution of the white dwarfs when dealing with axion masses larger than m{sub a} cos {sup 2}??> 5 meV (i.e. axion-electron coupling constant g{sub ae}?> 1.4× 10{sup -13}). We went beyond previous works by including 5 different derivations of the WDLF in our analysis. Then we have performed ?{sup 2}-tests to have a quantitative measure of the agreement between the theoretical WDLFs — computed under the assumptions of different axion masses and normalization methods --- and the observed WDLFs of the Galactic disk. While all the WDLF studied in this work disfavour axion masses in the range suggested by asteroseismology m{sub a} cos {sup 2}??> 10 meV; g{sub ae}?> 2.8× 10{sup -13}) lower axion masses can not be discarded from our current knowledge of the WDLF of the Galactic Disk. A larger set of completely independent derivations of the WDLF of the galactic disk as well as a detailed study of the uncertainties of the theoretical WDLFs is needed before quantitative constraints on the axion-electron coupling constant can be made.

  9. Rotating black hole thermodynamics with a particle probe

    SciTech Connect (OSTI)

    Gwak, Bogeun; Lee, Bum-Hoon

    2011-10-15

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

  10. Lumpy AdS$\\bf{_5\\times}$ S$\\bf{^5}$ Black Holes and Black Belts

    E-Print Network [OSTI]

    Oscar J. C. Dias; Jorge E. Santos; Benson Way

    2015-01-26

    Sufficiently small Schwarzschild black holes in global AdS$_5\\times$S$^5$ are Gregory-Laflamme unstable. We construct new families of black hole solutions that bifurcate from the onset of this instability and break the full SO$(6)$ symmetry group of the S$^5$ down to SO$(5)$. These new "lumpy" solutions are labelled by the harmonics $\\ell$. We find evidence that the $\\ell = 1$ branch never dominates the microcanonical/canonical ensembles and connects through a topology-changing merger to a localised black hole solution with S$^8$ topology. We argue that these S$^8$ black holes should become the dominant phase in the microcanonical ensemble for small enough energies, and that the transition to Schwarzschild black holes is first order. Furthermore, we find two branches of solutions with $\\ell = 2$. We expect one of these branches to connect to a solution containing two localised black holes, while the other branch connects to a black hole solution with horizon topology $\\mathrm S^4\\times\\mathrm S^4$ which we call a "black belt".

  11. The different phases of hairy black holes in AdS5 space

    E-Print Network [OSTI]

    Gaston Giribet; Andres Goya; Julio Oliva

    2014-12-31

    We investigate the thermodynamics of hairy black holes in asymptotically Anti-de Sitter (AdS) space, including backreaction. Resorting to the Euclidean path integral approach, we show that matter conformally coupled to Einstein gravity in five dimensions may exhibit a phase transition whose endpoint turns out to be a hairy black hole in AdS5 space. The scalar field configuration happens to be regular everywhere outside and on the horizon, and behaves asymptotically in such a way that respects the AdS boundary conditions that are relevant for AdS/CFT. The theory presents other peculiar features in the ultraviolet, like the existence of black holes with arbitrarily low temperature in AdS5. This provides a simple setup in which the fully backreacting problem of a hair forming in AdS at certain critical temperature can be solved analytically.

  12. The different phases of hairy black holes in AdS5 space

    E-Print Network [OSTI]

    Giribet, Gaston; Oliva, Julio

    2015-01-01

    We investigate the thermodynamics of hairy black holes in asymptotically Anti-de Sitter (AdS) space, including backreaction. Resorting to the Euclidean path integral approach, we show that matter conformally coupled to Einstein gravity in five dimensions may exhibit a phase transition whose endpoint turns out to be a hairy black hole in AdS5 space. The scalar field configuration happens to be regular everywhere outside and on the horizon, and behaves asymptotically in such a way that respects the AdS boundary conditions that are relevant for AdS/CFT. The theory presents other peculiar features in the ultraviolet, like the existence of black holes with arbitrarily low temperature in AdS5. This provides a simple setup in which the fully backreacting problem of a hair forming in AdS at certain critical temperature can be solved analytically.

  13. Quasinormal modes of magnetic and electric black branes versus far from equilibrium anisotropic fluids

    E-Print Network [OSTI]

    Janiszewski, Stefan

    2015-01-01

    Detailed knowledge about equilibration processes is of interest for various fields of physics, including heavy ion collision experiments and quantum quenched condensed matter systems. We study the approach to equilibrium at late times within two types of strongly coupled thermal systems in 3+1 dimensions: systems in the presence of (i) a non-zero charge density, or (ii) a magnetic field at vanishing charge density. Utilizing the gauge/gravity correspondence, we map the aforementioned problem to the computation of quasinormal frequencies around two particular classes of black branes within the Einstein-Maxwell theory. We compute (i) the tensor quasinormal modes of Reissner-Nordstr\\"om black branes and (ii) the scalar, as well as tensor quasinormal modes of magnetic black branes. Some of these quasinormal modes correspond to the late-time relaxation of the above systems after starting with initial pressure anisotropy. We provide benchmarks which need to be matched at late times by all holographic thermalization...

  14. Regge-Wheeler equation, stability, and greybody factors for dirty black holes

    E-Print Network [OSTI]

    Boonserm, Petarpa; Visser, Matt

    2013-01-01

    So-called "dirty" black holes are surrounded by non-zero stress-energy, rather than vacuum. The presence of the non-zero stress-energy modifies key features such as the surface gravity, the Regge-Wheeler equation, stability, and the greybody factors in a rather nontrivial way. We shall present general forms for the Regge-Wheeler equation for spin 0, spin 1, and for spin 2 axial perturbations in arbitrary static spherically symmetric spacetimes. Using very general features of these spacetimes, (in particular the classical energy conditions for the stress-energy surrounding the black hole), we extract several interesting and robust bounds on the behaviour of such systems, including rigorous bounds on the greybody factors for dirty black holes.

  15. Mining information from binary black hole mergers: a comparison of estimation methods for complex exponentials in noise

    E-Print Network [OSTI]

    Emanuele Berti; Vitor Cardoso; Jose A. Gonzalez; Ulrich Sperhake

    2007-06-17

    The ringdown phase following a binary black hole merger is usually assumed to be well described by a linear superposition of complex exponentials (quasinormal modes). In the strong-field conditions typical of a binary black hole merger, non-linear effects may produce mode coupling. Artificial mode coupling can also be induced by the black hole's rotation, if the radiation field is expanded in terms of spin-weighted spherical (rather than spheroidal) harmonics. Observing deviations from linear black hole perturbation theory requires optimal fitting techniques to extract ringdown parameters from numerical waveforms, which are inevitably affected by errors. So far, non-linear least-squares fitting methods have been used as the standard workhorse to extract frequencies from ringdown waveforms. These methods are known not to be optimal for estimating parameters of complex exponentials. Furthermore, different fitting methods have different performance in the presence of noise. The main purpose of this paper is to introduce the gravitational wave community to modern variations of a linear parameter estimation technique first devised in 1795 by Prony: the Kumaresan-Tufts and matrix pencil methods. Using "test" damped sinusoidal signals in Gaussian white noise we illustrate the advantages of these methods, showing that they have variance and bias at least comparable to standard non-linear least-squares techniques. Then we compare the performance of different methods on unequal-mass binary black hole merger waveforms. The methods we discuss should be useful both theoretically (to monitor errors and search for non-linearities in numerical relativity simulations) and experimentally (for parameter estimation from ringdown signals after a gravitational wave detection).

  16. Roadmap and Technical White Papers for 21st Century Truck Partnership...

    Energy Savers [EERE]

    Roadmap and Technical White Papers for 21st Century Truck Partnership Roadmap and Technical White Papers for 21st Century Truck Partnership Roadmap document for 21st Century Truck...

  17. Ecological Modelling 190 (2006) 171189 Local spatial modeling of white-tailed deer distribution

    E-Print Network [OSTI]

    2006-01-01

    spatial modeling techniques. We used one local modeling approach, geographically weighted regression (GWR rights reserved. Keywords: Geographically weighted regression; Ordinary linear-squares regression; White regression (White et al., 2004), logistic multiple regression (Pearce, 1987; Augustin et al., 1996

  18. Barriers to CHP with Renewable Portfolio Standards, Draft White Paper, September 2007

    Office of Energy Efficiency and Renewable Energy (EERE)

    A draft white paper discussing the barriers to combine heat and power (CHP) with renewable portfolio standards

  19. Head-on collisions of binary white dwarf-neutron stars: Simulations in full general relativity

    SciTech Connect (OSTI)

    Paschalidis, Vasileios; Etienne, Zachariah; Liu, Yuk Tung; Shapiro, Stuart L.

    2011-03-15

    We simulate head-on collisions from rest at large separation of binary white dwarf-neutron stars (WDNSs) in full general relativity. Our study serves as a prelude to our analysis of the circular binary WDNS problem. We focus on compact binaries whose total mass exceeds the maximum mass that a cold-degenerate star can support, and our goal is to determine the fate of such systems. A fully general relativistic hydrodynamic computation of a realistic WDNS head-on collision is prohibitive due to the large range of dynamical time scales and length scales involved. For this reason, we construct an equation of state (EOS) which captures the main physical features of neutron stars (NSs) while, at the same time, scales down the size of white dwarfs (WDs). We call these scaled-down WD models 'pseudo-WDs (pWDs)'. Using pWDs, we can study these systems via a sequence of simulations where the size of the pWD gradually increases toward the realistic case. We perform two sets of simulations; One set studies the effects of the NS mass on the final outcome, when the pWD is kept fixed. The other set studies the effect of the pWD compaction on the final outcome, when the pWD mass and the NS are kept fixed. All simulations show that after the collision, 14%-18% of the initial total rest mass escapes to infinity. All remnant masses still exceed the maximum rest mass that our cold EOS can support (1.92M{sub {center_dot}}), but no case leads to prompt collapse to a black hole. This outcome arises because the final configurations are hot. All cases settle into spherical, quasiequilibrium configurations consisting of a cold NS core surrounded by a hot mantle, resembling Thorne-Zytkow objects. Extrapolating our results to realistic WD compactions, we predict that the likely outcome of a head-on collision of a realistic, massive WDNS system will be the formation of a quasiequilibrium Thorne-Zytkow-like object.

  20. Holographic superconductor in the exact hairy black hole

    E-Print Network [OSTI]

    Yun Soo Myung; Chanyong Park

    2011-09-13

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

  1. THE HYPERCP DATA ACQUISITION D. M. Kaplan 2 , W. R. Luebke, A. Chakravorty, C. G. White, S. L. White

    E-Print Network [OSTI]

    Fermilab Experiment E871

    THE HYPERCP DATA ACQUISITION SYSTEM 1 D. M. Kaplan 2 , W. R. Luebke, A. Chakravorty, C. G. White, S 28--29, 1997. 2 E­mail: kaplan@fnal.gov 3 i.e., occurring via meson­antimeson mixing. 1 #12; Hyperon

  2. The Feynman integrand as a white noise distribution beyond perturbation theory

    SciTech Connect (OSTI)

    Grothaus, Martin; Vogel, Anna

    2008-06-18

    In this note the concepts of path integrals and techniques how to construct them are presented. Here we concentrate on a White Noise approach. Combining White Noise techniques with a generalized time-dependent Doss' formula Feynman integrands are constructed as white noise distributions beyond perturbation theory.

  3. THE WHITE MOUNTAIN POLARIMETER TELESCOPE AND AN UPPER LIMIT ON COSMIC MICROWAVE BACKGROUND POLARIZATION

    E-Print Network [OSTI]

    Timbie, Peter

    THE WHITE MOUNTAIN POLARIMETER TELESCOPE AND AN UPPER LIMIT ON COSMIC MICROWAVE BACKGROUND. Wuensche5 Received 2007 June 10; accepted 2008 March 16 ABSTRACT The White Mountain Polarimeter (WMPol microwave background. WMPol is located at an altitude of 3880 m on a plateau in the White Mountains

  4. Revisiting the BGE Attack on a White-Box AES Implementation

    E-Print Network [OSTI]

    International Association for Cryptologic Research (IACR)

    . White-box cryptography aims to protect the secret key of a cipher in an environment in which-box implementation of AES [5]. White-box cryptography aims to protect the confidentiality of the secret key device, or a set-top box. #12;In 2004, Billet et al. [3] presented an attack on the white-box AES

  5. A Grand Challenge for the Future Grid A PSERC White Paper

    E-Print Network [OSTI]

    the white paper, the lead authors consulted with industry and university PSERC members. Feedback on an earlyA Grand Challenge for the Future Grid A PSERC White Paper Power Systems Engineering Research Center A White Paper from the Power Systems Engineering Research Center Lead Authors Chris DeMarco, University

  6. High Efficiency White Organic Light Emission Device Based On New Orange Phosphorescence Material

    E-Print Network [OSTI]

    High Efficiency White Organic Light Emission Device Based On New Orange Phosphorescence Material University, Kowloon, Hong Kong ABSTRACT White light emitting device based on a new orange phosphorescent fabricated. The white OLED consists of it and a blue phosphorescent material FIrPic (iridum-bis(4

  7. Electrically charged black hole with scalar hair

    E-Print Network [OSTI]

    Cristian Martinez; Ricardo Troncoso

    2006-06-16

    An electrically charged black hole solution with scalar hair in four dimensions is presented. The self-interacting scalar field is real and it is minimally coupled to gravity and electromagnetism. The event horizon is a surface of negative constant curvature and the asymptotic region is locally an AdS spacetime. The asymptotic fall-off of the fields is slower than the standard one. The scalar field is regular everywhere except at the origin, and is supported by the presence of electric charge which is bounded from above by the AdS radius. In turn, the presence of the real scalar field smooths the electromagnetic potential everywhere. Regardless the value of the electric charge, the black hole is massless and has a fixed temperature. The entropy follows the usual area law. It is shown that there is a nonvanishing probability for the decay of the hairy black hole into a charged black hole without scalar field. Furthermore, it is found that an extremal black hole without scalar field is likely to undergo a spontaneous dressing up with a nontrivial scalar field, provided the electric charge is below a critical value.

  8. Perturbative String Thermodynamics near Black Hole Horizons

    E-Print Network [OSTI]

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

    2015-07-01

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

  9. Thermodynamics and Luminosities of Rainbow Black Holes

    E-Print Network [OSTI]

    Benrong Mu; Peng Wang; Haitang Yang

    2015-07-14

    Doubly special relativity (DSR) is an effective model for encoding quantum gravity in flat spacetime. As a result of the nonlinearity of the Lorentz transformation, the energy-momentum dispersion relation is modified. One simple way to import DSR to curved spacetime is \\textquotedblleft Gravity's rainbow", where the spacetime background felt by a test particle would depend on its energy. Focusing on the \\textquotedblleft Amelino-Camelia dispersion relation" which is $E^{2}=m^{2}+p^{2}\\left[ 1-\\eta\\left( E/m_{p}\\right) ^{n}\\right] $ with $n>0$, we investigate the thermodynamical properties of a Schwarzschild black hole and a static uncharged black string for all possible values of $\\eta$ and $n$ in the framework of rainbow gravity. It shows that there are non-vanishing minimum masses for these two black holes in the cases with $\\eta<0$ and $n\\geq2$. Considering effects of rainbow gravity on both the Hawking temperature and radius of the event horizon, we use the geometric optics approximation to compute luminosities of a 2D black hole, a Schwarzschild one and a static uncharged black string. It is found that the luminosities can be significantly suppressed or boosted depending on the values of $\\eta$ and $n$.

  10. Black Hole Spin in AGN and GBHCs

    E-Print Network [OSTI]

    Christopher S. Reynolds; Laura W. Brenneman; David Garofalo

    2004-10-05

    We discuss constraints on black hole spin and spin-related astrophysics as derived from X-ray spectroscopy. After a brief discussion about the robustness with which X-ray spectroscopy can be used to probe strong gravity, we summarize how these techniques can constrain black hole spin. In particular, we highlight XMM-Newton studies of the Seyfert galaxy MCG-6-30-15 and the stellar-mass black hole GX339-4. The broad X-ray iron line profile, together with reasonable and general astrophysical assumptions, allow a non-rotating black hole to be rejected in both of these sources. If we make the stronger assertion of no emission from within the innermost stable circular orbit, the MCG-6-30-15 data constrain the dimensionless spin parameter to be a>0.93. Furthermore, these XMM-Newton data are already providing evidence for exotic spin-related astrophysics in the central regions of this object. We conclude with a discussion of the impact that Constellation-X will have on the study of strong gravity and black hole spin.

  11. Investigating Dark Energy with Black Hole Binaries

    E-Print Network [OSTI]

    Laura Mersini-Houghton; Adam Kelleher

    2009-06-08

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

  12. Self-similar cosmological solutions with dark energy. II. Black holes, naked singularities, and wormholes

    SciTech Connect (OSTI)

    Maeda, Hideki; Harada, Tomohiro; Carr, B. J.

    2008-01-15

    We use a combination of numerical and analytical methods, exploiting the equations derived in a preceding paper, to classify all spherically symmetric self-similar solutions which are asymptotically Friedmann at large distances and contain a perfect fluid with equation of state p=({gamma}-1){mu} with 0<{gamma}<2/3. The expansion of the Friedmann universe is accelerated in this case. We find a one-parameter family of self-similar solutions representing a black hole embedded in a Friedmann background. This suggests that, in contrast to the positive pressure case, black holes in a universe with dark energy can grow as fast as the Hubble horizon if they are not too large. There are also self-similar solutions which contain a central naked singularity with negative mass and solutions which represent a Friedmann universe connected to either another Friedmann universe or some other cosmological model. The latter are interpreted as self-similar cosmological white hole or wormhole solutions. The throats of these wormholes are defined as two-dimensional spheres with minimal area on a spacelike hypersurface and they are all nontraversable because of the absence of a past null infinity.

  13. The effect of mass-segregation on gravitational wave sources near massive black holes

    E-Print Network [OSTI]

    Clovis Hopman; Tal Alexander

    2006-03-13

    Gravitational waves (GWs) from the inspiral of compact remnants (CRs) into massive black holes (MBHs) will be observable to cosmological distances. While a CR spirals in, 2-body scattering by field stars may cause it to fall into the MBH before reaching a short period orbit that would give an observable signal. As a result, only CRs very near (~0.01 pc) the MBH can spiral in successfully. In a multi-mass stellar population, the heaviest objects sink to the center, where they are more likely to slowly spiral into the MBH without being swallowed prematurely. We study how mass-segregation modifies the stellar distribution and the rate of GW events. We find that the inspiral rate per galaxy for white dwarfs is 30 per Gyr, for neutron stars 6 per Gyr, and for stellar black holes (SBHs) 250 per Gyr. The high rate for SBHs is due to their extremely steep density profile, n_{BH}(r)\\propto r^{-2}. The GW detection rate will be dominated by SBHs.

  14. Enhancement of Sensitivity-Bandwidth Product of Interferometric GW Detectors using White Light Cavities

    E-Print Network [OSTI]

    M. Salit; M. S. Shahriar

    2009-06-11

    The effect of gravitational waves (GWs) has been observed indirectly, by monitoring the change in the orbital frequency of neutron stars in a binary system as they lose energy via gravitational radiation. However, GWs have not yet been observed directly. The initial LIGO apparatus has not yet observed GWs. The Advanced LIGO (AdLIGO) will use a combination of improved techniques in order to increase the sensitivity. Along with power recycling and a higher power laser source, the AdLIGO will employ signal recycling (SR). While SR would increase sensitivity, it would also reduce the bandwidth significantly. Previously, we and others have investigated, theoretically and experimentally, the feasibility of using a White Light Cavity (WLC) to circumvent this constraint. However, in the previous work, it was not clear how one would incorporate the white light cavity effect. Here, we first develop a general model for Michelson-Interferometer based GW detectors that can be easily adapted to include the effects of incorporating a WLC into the design. We then describe a concrete design of a WLC constructed as a compound mirror, to replace the signal recycling mirror. This design is simple, robust, completely non-invasive, and can be added to the AdLIGO system without changing any other optical elements. We show a choice of parameters for which the signal sensitivity as well as the bandwidth are enhanced significantly over what is planned for the AdLIGO, covering the entire spectrum of interest for gravitational waves.

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

    SciTech Connect (OSTI)

    Barrett, Tate

    2014-07-01

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

  16. Rotating black lens solution in five dimensions

    SciTech Connect (OSTI)

    Chen Yu; Teo, Edward

    2008-09-15

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

  17. Neutrino Majorana Mass from Black Hole

    E-Print Network [OSTI]

    Yosuke Uehara

    2002-05-25

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

  18. Numerical Analysis of Black Hole Evaporation

    E-Print Network [OSTI]

    Tsvi Piran; Andrew Strominger

    1993-04-28

    Black hole formation/evaporation in two-dimensional dilaton gravity can be described, in the limit where the number $N$ of matter fields becomes large, by a set of second-order partial differential equations. In this paper we solve these equations numerically. It is shown that, contrary to some previous suggestions, black holes evaporate completely a finite time after formation. A boundary condition is required to evolve the system beyond the naked singularity at the evaporation endpoint. It is argued that this may be naturally chosen so as to restore the system to the vacuum. The analysis also applies to the low-energy scattering of $S$-wave fermions by four-dimensional extremal, magnetic, dilatonic black holes.

  19. No Supermassive Black Hole in M33?

    E-Print Network [OSTI]

    David Merritt; Laura Ferrarese; Charles L. Joseph

    2001-07-20

    We analyze optical long-slit spectroscopy of the nucleus of M33 obtained from the Space Telescope Imaging Spectrograph aboard the Hubble Space Telescope. Rather than the steep rise expected within the radius of influence of a supermassive black hole, the velocity dispersion drops significantly within the inner parsec. Dynamical modelling yields an estimated upper limit of 3000 solar masses for the mass of a central compact object. This upper limit is however consistent within the uncertainties with the mass predicted by the M-sigma relation, which is between 2000 and 20,000 solar masses. We therefore can not conclude that the presence of a massive black hole in the nucleus of M33 would require a different formation mechanism from that of the black holes detected in galaxies with more luminous bulges.

  20. Black hole Meissner effect and Blandford-Znajek jets

    E-Print Network [OSTI]

    Penna, Robert

    Spinning black holes tend to expel magnetic fields. In this way they are similar to superconductors. It has been a persistent concern that this black hole “Meissner effect” could quench jet power at high spins. This would ...

  1. Virtual Black Holes in Hyperbolic Metamaterials

    E-Print Network [OSTI]

    Igor I. Smolyaninov

    2011-01-24

    Optical space in electromagnetic metamaterials may be engineered to emulate various exotic space-time geometries. However, these metamaterial models are limited in many respects. It is believed that real physical space-time strongly fluctuates on the Planck scale. These fluctuations are usually described as virtual black holes. Static metamaterial models introduced so far do not exhibit similar behavior. Here we demonstrate that thermal fluctuations of optical space in hyperbolic metamaterials lead to creation of virtual electromagnetic black holes. This effect is very large if the dielectric component of the metamaterial exhibits critical opalescence.

  2. Vacuum polarization for lukewarm black holes

    E-Print Network [OSTI]

    Elizabeth Winstanley; Phil M. Young

    2007-12-20

    We compute the renormalized expectation value of the square of a quantum scalar field on a Reissner-Nordstrom-de Sitter black hole in which the temperatures of the event and cosmological horizons are equal (`lukewarm' black hole). Our numerical calculations for a thermal state at the same temperature as the two horizons indicate that this renormalized expectation value is regular on both the event and cosmological horizons. We are able to show analytically, using an approximation for the field modes near the horizons, that this is indeed the case.

  3. Thermal stability of radiant black holes

    E-Print Network [OSTI]

    Parthasarathi Majumdar

    2006-04-06

    Beginning with a brief sketch of the derivation of Hawking's theorem of horizon area increase, based on the Raychaudhuri equation, we go on to discuss the issue as to whether generic black holes, undergoing Hawking radiation, can ever remain in stable thermal equilibrium with that radiation. We derive a universal criterion for such a stability, which relates the black hole mass and microcanonical entropy, both of which are well-defined within the context of the Isolated Horizon, and in principle calculable within Loop Quantum Gravity. The criterion is argued to hold even when thermal fluctuations of electric charge are considered, within a {\\it grand} canonical ensemble.

  4. Magnetized black hole as a gravitational lens

    E-Print Network [OSTI]

    R. A. Konoplya

    2006-11-19

    We use the Ernst-Schwarzschild solution for a black hole immersed in a uniform magnetic field to estimate corrections to the bending angle and time delay due-to presence of weak magnetic fields in galaxies and between galaxies, and also due-to influence of strong magnetic field near supermassive black holes. The magnetic field creates a kind of confinement in space, that leads to increasing of the bending angle and time delay for a ray of light propagating in the equatorial plane.

  5. Multiple phase estimation for arbitrary pure states under white noise

    E-Print Network [OSTI]

    Yao Yao; Li Ge; Xing Xiao; Xiaoguang Wang; C. P. Sun

    2014-09-08

    In any realistic quantum metrology scenarios, the ultimate precision in the estimation of parameters is limited not only by the so-called Heisenberg scaling, but also the environmental noise encountered by the underlying system. In the context of quantum estimation theory, it is of great significance to carefully evaluate the impact of a specific type of noise on the corresponding quantum Fisher information (QFI) or quantum Fisher information matrix (QFIM). Here we investigate the multiple phase estimation problem for a natural parametrization of arbitrary pure states under white noise. We obtain the explicit expression of the symmetric logarithmic derivative (SLD) and hence the analytical formula of QFIM. Moreover, the attainability of the quantum Cram\\'{e}r-Rao bound (QCRB) is confirmed by the commutability of SLDs and the optimal estimators are elucidated for the experimental purpose. These findings generalize previously known partial results and highlight the role of white noise in quantum metrology.

  6. Spectral modeling of gaseous metal disks around DAZ white dwarfs

    E-Print Network [OSTI]

    K. Werner; T. Nagel; T. Rauch

    2008-09-30

    We report on our attempt for the first non-LTE modeling of gaseous metal disks around single DAZ white dwarfs recently discovered by Gaensicke et al. and thought to originate from a disrupted asteroid. We assume a Keplerian rotating viscous disk ring composed of calcium and hydrogen and compute the detailed vertical structure and emergent spectrum. We find that the observed infrared CaII emission triplet can be modeled with a hydrogen-deficient gas ring located at R=1.2 R_sun, inside of the tidal disruption radius, with Teff about 6000 K and a low surface mass density of about 0.3 g/cm**2. A disk having this density and reaching from the central white dwarf out to R=1.2 R_sun would have a total mass of 7 10**21 g, corresponding to an asteroid with about 160 km diameter.

  7. The Properties of Matter in White Dwarfs and Neutron Stars

    E-Print Network [OSTI]

    Shmuel Balberg; Stuart L. Shapiro

    2000-04-24

    White dwarfs and neutron stars are stellar objects with masses comparable to that of our sun. However, as the endpoint stages of stellar evolution, these objects do not sustain any thermonuclear burning and therefore can no longer support the gravitational load of their own mass by generating thermal pressure. Rather, matter in their interiors is compressed to much higher densities than commonly found in normal stars, and pressure is created by degenerate fermion kinetic energy and particle interactions. As a result, white dwarfs and neutron stars offer unique cosmic laboratories for studying matter at very high densities. In this review we discuss the basic properties of condensed matter at extreme densities and summarize the extent to which these properties can be examined by observations of compact objects.

  8. Radionuclide concentrations in white sturgeon from the Columbia River

    SciTech Connect (OSTI)

    Dauble, D.D.; Price, K.R.; Poston, T.M.

    1992-09-01

    Although radioactive releases from the US Department of Energy`s Hanford Site have been monitored in the environment since the reactors began operating in 1945, recent information regarding historical releases of radionuclides has led to renewed interest in estimating human exposure to radionuclides at Hanford. Knowledge of the fate of radionuclides in some fish species may be important because of the potential for food-chain transfer to humans. White sturgeon (Acipenser transmontanus) were selected for study because they are long-lived, reside year-round in the Hanford Reach, are benthic, and are an important commercial and sport species in the Columbia River. They also have a greater potential for accumulating persistent radionuclides than shorter-lived species with pelagic and/or anadromous life histories. The purpose of our study was to summarize data on historical concentrations of industrial radionuclides in white sturgeon and to collect additional data on current body burdens in the Columbia River.

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

    E-Print Network [OSTI]

    I. B. Khriplovich

    2002-03-31

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

  10. UofT Wireless Network BlackBerry 6 Setup

    E-Print Network [OSTI]

    UofT Wireless Network BlackBerry 6 Setup Note:theseinstructionsweretestedonaBlackBerryBold9700,OS6-4357,help.desk@utoronto.ca). UofT Wireless Network BlackBerry 10 Setup Note: these instructions were tested on a BlackBerry Q10. 1. Before you can use the UofT wireless network, you must verify your UTORid (you

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

    Office of Scientific and Technical Information (OSTI)

    ASTROPHYSICS; BLACK HOLES; COMPARATIVE EVALUATIONS; CORRELATIONS; COSMOLOGY; GALAXIES; GALAXY NUCLEI; NONLUMINOUS MATTER; OSCILLATIONS; QUASARS; VELOCITY Word Cloud More Like This...

  12. Nuclear Arms Control R&D Consortium includes Los Alamos

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

    Nuclear Arms Control R&D Consortium includes Los Alamos Nuclear Arms Control R&D Consortium includes Los Alamos A consortium led by the University of Michigan that includes LANL as...

  13. GRAVITATIONAL WAVE SIGNATURES IN BLACK HOLE FORMING CORE COLLAPSE

    SciTech Connect (OSTI)

    Cerdá-Durán, Pablo; DeBrye, Nicolas; Aloy, Miguel A.; Font, José A.; Obergaulinger, Martin

    2013-12-20

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

  14. Constraints on the density perturbation spectrum from primordial black holes

    E-Print Network [OSTI]

    Anne M Green; Andrew R Liddle

    1997-04-25

    We re-examine the constraints on the density perturbation spectrum, including its spectral index $n$, from the production of primordial black holes. The standard cosmology, where the Universe is radiation dominated from the end of inflation up until the recent past, was studied by Carr, Gilbert and Lidsey; we correct two errors in their derivation and find a significantly stronger constraint than they did, $n \\lesssim 1.25$ rather than their 1.5. We then consider an alternative cosmology in which a second period of inflation, known as thermal inflation and designed to solve additional relic over-density problems, occurs at a lower energy scale than the main inflationary period. In that case, the constraint weakens to $n \\lesssim 1.3$, and thermal inflation also leads to a `missing mass' range, $10^{18} g \\lesssim M \\lesssim 10^{26} g$, in which primordial black holes cannot form. Finally, we discuss the effect of allowing for the expected non-gaussianity in the density perturbations predicted by Bullock and Primack, which can weaken the constraints further by up to 0.05.

  15. GIS and Digital Geospatial Data at TAMU Libraries - White Paper 

    E-Print Network [OSTI]

    Weimer, Kathy

    2008-08-22

    Geospatial Data at TAMU Libraries White Paper May 2005 Kathy Weimer Coordinator of Maps/GIS Background of GIS in Libraries GIS, geographical information systems, is an integrated system of computer hardware, software, data and trained people.../software and data management issues related to GIS implementation. Foremost among these papers are ARL’s Spec Kit 219 (Transforming Libraries, Issues and Innovations in Geographic Information Systems, 1997) and Spec Kit 238 (The ARL Geographic Information...

  16. White LED Benchmark of 65 Lumens Per Watt Achieved

    Broader source: Energy.gov [DOE]

    Novel chip design and the balance of multiple interrelated design parameters have enabled Cree, Inc.'s Santa Barbara Technology Center to demonstrate white LEDs with efficacies greater than 65 lumens per watt at 350 mA. The results are particularly significant because they were achieved with a pre-production prototype chip using the same package used in Cree's commercially available XLamp® 7090 high power LED, rather than a laboratory device.

  17. Degree of Whiteness and Maturity Among World Cotton Cultivars 

    E-Print Network [OSTI]

    Gregory, Kendra

    2012-07-16

    of spectrophotometers; while they demonstrated that inter-instrument agreement is possible, the use of glass between the cotton fibers and the machines diminished that 7 7 agreement (Rodgers et al., 2006; Shofner et al., 2006). The AMS system is a 2-D color.... Wayne Smith Eric F. Hequet Committee Member, J. Tom Cothren Head of Department, David D. Baltensperger May 2012 Major Subject: Plant Breeding iii iii ABSTRACT Degree of Whiteness and Maturity among World Cotton Cultivars. (May 2012...

  18. Efficacy of 45 lm/W Achieved in White OLED

    Broader source: Energy.gov [DOE]

    Universal Display Corporation (UDC) successfully demonstrated an all phosphorescent white organic light emitting diode (WOLED™) with a power efficacy of 45 lm/W at 1,000 cd/m2. This high-efficacy device was enabled by lowering the device operating voltage, increasing the outcoupling efficiency to ~40% from ~20%, and by incorporating highly efficient phosphorescent emitters that are capable of converting nearly all current passing through a WOLED into light.

  19. Newport News in Review, ch. 47, segment includes TEDF groundbreaking...

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

    https:www.jlab.orgnewsarticlesnewport-news-review-ch-47-segment-includes-tedf-groundbreaking-event Newport News in Review, ch. 47, segment includes TEDF groundbreaking event...

  20. Solar Energy Education. Reader, Part II. Sun story. [Includes...

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

    Part II. Sun story. Includes glossary Citation Details In-Document Search Title: Solar Energy Education. Reader, Part II. Sun story. Includes glossary You are...