Sample records for black carbon mass

  1. 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 ...

  2. 6, 34193463, 2006 Black carbon or

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

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

  3. Black Holes of Negative Mass

    E-Print Network [OSTI]

    R. B. Mann

    1997-05-06T23:59:59.000Z

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

  4. Black Hole Interior Mass Formula

    E-Print Network [OSTI]

    Parthapratim Pradhan

    2014-05-06T23:59:59.000Z

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

  5. Stability of Biomass-derived Black Carbon in Soils . | EMSL

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

    Stability of Biomass-derived Black Carbon in Soils . Stability of Biomass-derived Black Carbon in Soils . Abstract: Black carbon (BC) may play an important role in the global C...

  6. Will black carbon mitigation dampen aerosol indirect forcing?1 W.-T. Chen1

    E-Print Network [OSTI]

    Nenes, Athanasios

    of solar radiation reaching the Earth's surface. Ambient27 measurements indicate that freshly emitted BC, Pasadena, CA, USA11 *To whom correspondence should be addressed12 13 If mitigation of black carbon (BC17 of primary black carbon/organic carbon (BC/OC) mass and number emissions from fossil18 fuel

  7. Size fractionation of black and organic particulate carbon from fires. Final report

    SciTech Connect (OSTI)

    Dod, R.L.; Mowrer, F.; Gundel, L.A.; Williamson, R.B.; Novakov, T.

    1985-11-01T23:59:59.000Z

    Emission factors to total smoke particulates as well as organic and black carbon have been measured as a function of size for a set of building materials typical of those used in urban construction. Black carbon emissions (mass per fuel mass) were similar among the wood fuels studied, although the dominant form of combustion varied from flaming to smoldering. Black carbon was found predominantly in the finest size ranges (less than or equal to 0.20 ..mu..m). Polyurethane foam produced a greater emission of black carbon, and the particle size distribution of that carbon extended to much larger aerodynamic diameters than did those of the wood samples. For the fuels tested, total smoke particle emissions ranged from 0.3 to 2.3 percent of fuel mass; black carbon emissions were 0.03 to 0.3 percent of fuel mass.

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

    E-Print Network [OSTI]

    Beaucage, Gregory

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

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

    E-Print Network [OSTI]

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

    2013-01-01T23:59:59.000Z

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

  10. Black Carbon in the Soil Carbon Cycle: Is it an Oxidation Resistant End-Product?

    E-Print Network [OSTI]

    Fischlin, Andreas

    Black Carbon in the Soil Carbon Cycle: Is it an Oxidation Resistant End-Product? Simone Submitted on December 21, 2007 Reviewed April 1, 2008 Abstract Black carbon (BC) is a very oxidation, charcoal, and soot. Due to its high recalcitrance, black carbon might act as a long-term carbon sink

  11. Neutrino Majorana Mass from Black Hole

    E-Print Network [OSTI]

    Yosuke Uehara

    2002-05-25T23:59:59.000Z

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

  12. 4, 34853533, 2004 Black carbon from

    E-Print Network [OSTI]

    Boyer, Edmond

    . Important climatic effects due to direct impacts on radiation can be expected (e.g. Schult et al., 1997 and Seinfeld, 2002; Jacobson, 2002). Additionally, indirect climatic effects due to impacts on cloud droplet Discussions Simulating the global atmospheric black carbon cycle: a revisit to the contribution of aircraft

  13. Coal water suspensions involving carbon black

    SciTech Connect (OSTI)

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

    1988-10-25T23:59:59.000Z

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

  14. atmospheric black carbon: Topics by E-print Network

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

    Next Page Last Page Topic Index 1 II. Black Carbon, Atmospheric Brown Clouds and Greenhouse Effect: Background CiteSeer Summary: satellite. The optical depth is a good index for...

  15. Application of pyrolized carbon black from scrap tires in asphalt pavement design and construction

    SciTech Connect (OSTI)

    Park, T.; Coree, B.J. [Indiana Department of Transportation, West Lafayette, IN (United States). Division of Research; Lovell, C.W. [Purdue Univ., West Lafayette, IN (United States). School of Civil Engineering

    1995-12-31T23:59:59.000Z

    According to EPA reports (1991) of the over 242 million waste generated each year in the United State, 5% are exported, 6% recycled, 11% incinerated, and 78% are landfilled, stockpiled, or illegally dumped. A variety of uses for these tires are being studied. Among these is pyrolysis which produces 5 5% of oil, 25% of carbon black, 9% of steel, 5% of fiber and 6% of gas. Pyrolized carbon black contains 9 % of ash, 4% of sulfur, 12% of butadine copolymer and 75% of carbon black. The objective of this research is to investigate the viability of using PCB as an additive in hot mix asphalt. The use of PCB in asphalt pavement is expected not only to improve the performance of conventional asphalt, but also to provide a means for the mass disposal of waste fires.

  16. The mass function of high redshift seed black holes

    E-Print Network [OSTI]

    Giuseppe Lodato; Priyamvada Natarajan

    2007-02-13T23:59:59.000Z

    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.

  17. Masses of Stellar Black Holes and Testing Theories of Gravitation

    E-Print Network [OSTI]

    K. A. Postnov; A. M. Cherepashchuk

    2004-01-22T23:59:59.000Z

    We analyze the mass distribution of stellar black holes derived from the light and radial velocity curves of optical stars in close binary systems using dynamical methods. The systematic errors inherent in this approach are discussed. These are associated primarily with uncertainties in models for the contribution from gaseous structures to the optical brightness of the systems under consideration. The mass distribution is nearly flat in the range 4-15M_sun. This is compared with the mass distribution for black holes in massive close binaries, which can be manifest as ultraluminous X-ray sources (L_x > 10^39 erg/s) observed in other galaxies. If the X-ray luminosities of these objects correspond to the Eddington limit, the black-hole mass distribution should be described by a power law, which is incompatible with the flat shape derived dynamically from observations of close binaries in our Galaxy. One possible explanation of this discrepancy is the rapid evaporation of stellar-mass black holes predicted in recent multi-dimensional models of gravity. This hypothesis can be verifed by measuring the stellar black-hole mass spectrum or finding isolated or binary black holes with masses below 3M_sun.

  18. Black carbon in Arctic snow and its effect on surface albedo

    E-Print Network [OSTI]

    1 Black carbon in Arctic snow and its effect on surface albedo Stephen Warren, University wavelengths: ice is nearly transparent. Absorptive impurities: Black carbon (soot) Brown carbon (organics broadband albedo: 83% 71% (2) by addition of black carbon (BC) (20 ppb): 0.5% for r = 100 µm 1.6% for r

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

    E-Print Network [OSTI]

    Toohey, Darin W.

    Black Carbon Emissions by Rocket Engines Types of rocket engines Emissions Liquid Hydrogen) and tetroxide (24) Large amounts of nitrogen oxides. Kerosene Rockets 2 and black carbon (soot). Focus: New carbon in the stratosphere. The large amount of black carbon emitted by these engines is caused

  20. Does black carbon and humic materials in snow and ice Supervisor: Martin D. King

    E-Print Network [OSTI]

    Royal Holloway, University of London

    ) burner technology changes the and optics properties of black carbon change. As little as 10 ng of Black carbon in snowpack is a factor of two more effective than carbon dioxide in changing global air with different black carbon and humic loadings, modeling the optical properties of the snow/ice and measuring

  1. Proposed Studentship Does black carbon and humic materials in snow and ice

    E-Print Network [OSTI]

    Royal Holloway, University of London

    ) black carbon is increasing or (b) burner technology changes the and optics properties of black carbon carbon dioxide in changing global air temperatures.2 The successful candidate will set-up and conductProposed Studentship Does black carbon and humic materials in snow and ice decay? Supervisors: Dr

  2. Structure and Mass Absorption of Hypothetical Terrestrial Black Holes

    E-Print Network [OSTI]

    A. P. VanDevender; J. Pace VanDevender

    2011-05-02T23:59:59.000Z

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

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

    E-Print Network [OSTI]

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

    2007-06-05T23:59:59.000Z

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

  4. Adjoint Inverse Modeling of Black Carbon During ACE-A. Hakami 1

    E-Print Network [OSTI]

    Sandu, Adrian

    in northeast China and Japan are increased. 1 #12;Introduction Black (or elemental) carbon (BC) is the mainAdjoint Inverse Modeling of Black Carbon During ACE- Asia A. Hakami 1 , D. K. Henze 1 , J. H model is used for inverse modeling of black carbon during ACE- Asia. We use the 4D-Var approach

  5. Direct climate effect of black carbon in China and its impact on dust storms

    E-Print Network [OSTI]

    Liou, K. N.

    Click Here for Full Article Direct climate effect of black carbon in China and its impact on dust aerosols in China, particularly black carbon (BC), is the primary reason for precipitation and temperature, W. Chen, and H. Liao (2010), Direct climate effect of black carbon in China and its impact on dust

  6. amorphous carbon blacks: Topics by E-print Network

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

    carbon blacks First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 RESEARCH PAPER Amorphous dysprosium...

  7. A photometric method to determine supermassive black hole masses

    E-Print Network [OSTI]

    A. W. Graham; P. Erwin; N. Caon; I. Trujillo

    2002-06-14T23:59:59.000Z

    We report the discovery of a strong correlation between the shape of a bulge's light-profile and the mass of its central supermassive black hole (M_{bh}). We find that log(M_{bh}/M_{sun}) = 2.91(+/-0.38)log(n) + 6.37(+/-0.21), where `n' is the Sersic r^{1/n} shape index of the bulge. This correlation is marginally stronger than the relationship between the logarithm of the stellar velocity dispersion and log(M_{bh}) and has comparable scatter. It therefore offers a cheap (in terms of telescope time) alternative to estimating the masses of supermassive black holes.

  8. Partial replacement of carbon fiber by carbon black in multifunctional cementmatrix composites

    E-Print Network [OSTI]

    Chung, Deborah D.L.

    strain at failure, while the compressive strength is maintained. The increased workability due of carbon fiber to cement with carbon black decreases the compressive strength, strain at failure detection and structural vibration control [11­26]. In dam- age sensing, the composite is used as a damage

  9. On Black Hole Masses and Radio Loudness in AGN

    E-Print Network [OSTI]

    Ari Laor

    2000-09-13T23:59:59.000Z

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

  10. Mass and Free Energy of Lovelock Black Holes

    E-Print Network [OSTI]

    David Kastor; Sourya Ray; Jennie Traschen

    2011-06-20T23:59:59.000Z

    An explicit formula for the ADM mass of an asymptotically AdS black hole in a generic Lovelock gravity theory is presented, identical in form to that in Einstein gravity, but multiplied by a function of the Lovelock coupling constants and the AdS curvature radius. A Gauss' law type formula relates the mass, which is an integral at infinity, to an expression depending instead on the horizon radius. This and other thermodynamic quantities, such as the free energy, are then analyzed in the limits of small and large horizon radius, yielding results that are independent of the detailed choice of Lovelock couplings. In even dimensions, the temperature diverges in both limits, implying the existence of a minimum temperature for black holes. The negative free energy of sufficiently large black holes implies the existence of a Hawking-Page transition. In odd dimensions the temperature still diverges for large black holes, which again have negative free energy. However, the temperature vanishes as the horizon radius tends to zero and sufficiently small black holes have positive specific heat.

  11. Search for Gravitational Waves from Intermediate Mass Binary Black Holes

    E-Print Network [OSTI]

    the LIGO Scientific Collaboration; the Virgo Collaboration; J. Abadie; B. P. Abbott; R. Abbott; T. D. Abbott; M. Abernathy; T. Accadia; F. Acernese; C. Adams; R. Adhikari; C. Affeldt; M. Agathos; K. Agatsuma; P. Ajith; B. Allen; E. Amador Ceron; D. Amariutei; S. B. Anderson; W. G. Anderson; K. Arai; M. A. Arain; M. C. Araya; S. M. Aston; P. Astone; D. Atkinson; P. Aufmuth; C. Aulbert; B. E. Aylott; S. Babak; P. Baker; G. Ballardin; S. Ballmer; J. C. B. Barayoga; D. Barker; F. Barone; B. Barr; L. Barsotti; M. Barsuglia; M. A. Barton; I. Bartos; R. Bassiri; M. Bastarrika; A. Basti; J. Batch; J. Bauchrowitz; Th. S. Bauer; M. Bebronne; D. Beck; B. Behnke; M. Bejger; M. G. Beker; A. S. Bell; A. Belletoile; I. Belopolski; M. Benacquista; J. M. Berliner; A. Bertolini; J. Betzwieser; N. Beveridge; P. T. Beyersdorf; I. A. Bilenko; G. Billingsley; J. Birch; R. Biswas; M. Bitossi; M. A. Bizouard; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; B. Bland; M. Blom; O. Bock; T. P. Bodiya; C. Bogan; R. Bondarescu; F. Bondu; L. Bonelli; R. Bonnand; R. Bork; M. Born; V. Boschi; S. Bose; L. Bosi; B. Bouhou; S. Braccini; C. Bradaschia; P. R. Brady; V. B. Braginsky; M. Branchesi; J. E. Brau; J. Breyer; T. Briant; D. O. Bridges; A. Brillet; M. Brinkmann; V. Brisson; M. Britzger; A. F. Brooks; D. A. Brown; T. Bulik; H. J. Bulten; A. Buonanno; J. Burguet-Castell; D. Buskulic; C. Buy; R. L. Byer; L. Cadonati; G. Cagnoli; E. Calloni; J. B. Camp; P. Campsie; J. Cannizzo; K. Cannon; B. Canuel; J. Cao; C. D. Capano; F. Carbognani; L. Carbone; S. Caride; S. Caudill; M. Cavaglia; F. Cavalier; R. Cavalieri; G. Cella; C. Cepeda; E. Cesarini; O. Chaibi; T. Chalermsongsak; P. Charlton; E. Chassande-Mottin; S. Chelkowski; W. Chen; X. Chen; Y. Chen; A. Chincarini; A. Chiummo; H. Cho; J. Chow; N. Christensen; S. S. Y. Chua; C. T. Y. Chung; S. Chung; G. Ciani; F. Clara; D. E. Clark; J. Clark; J. H. Clayton; F. Cleva; E. Coccia; P. -F. Cohadon; C. N. Colacino; J. Colas; A. Colla; M. Colombini; A. Conte; R. Conte; D. Cook; T. R. Corbitt; M. Cordier; N. Cornish; A. Corsi; C. A. Costa; M. Coughlin; J. -P. Coulon; P. Couvares; D. M. Coward; M. Cowart; D. C. Coyne; J. D. E. Creighton; T. D. Creighton; A. M. Cruise; A. Cumming; L. Cunningham; E. Cuoco; R. M. Cutler; K. Dahl; S. L. Danilishin; R. Dannenberg; S. D'Antonio; K. Danzmann; V. Dattilo; B. Daudert; H. Daveloza; M. Davier; E. J. Daw; R. Day; T. Dayanga; R. De Rosa; D. DeBra; G. Debreczeni; W. Del Pozzo; M. del Prete; T. Dent; V. Dergachev; R. DeRosa; R. DeSalvo; S. Dhurandhar; L. Di Fiore; A. Di Lieto; I. Di Palma; M. Di Paolo Emilio; A. Di Virgilio; M. Diaz; A. Dietz; F. Donovan; K. L. Dooley; M. Drago; R. W. P. Drever; J. C. Driggers; Z. Du; J. -C. Dumas; S. Dwyer; T. Eberle; M. Edgar; M. Edwards; A. Effler; P. Ehrens; G. Endroczi; R. Engel; T. Etzel; K. Evans; M. Evans; T. Evans; M. Factourovich; V. Fafone; S. Fairhurst; Y. Fan; B. F. Farr; D. Fazi; H. Fehrmann; D. Feldbaum; F. Feroz; I. Ferrante; F. Fidecaro; L. S. Finn; I. Fiori; R. P. Fisher; R. Flaminio; M. Flanigan; S. Foley; E. Forsi; L. A. Forte; N. Fotopoulos; J. -D. Fournier; J. Franc; S. Frasca; F. Frasconi; M. Frede; M. Frei; Z. Frei; A. Freise; R. Frey; T. T. Fricke; D. Friedrich; P. Fritschel; V. V. Frolov; M. -K. Fujimoto; P. J. Fulda; M. Fyffe; J. Gair; M. Galimberti; L. Gammaitoni; J. Garcia; F. Garufi; M. E. Gaspar; G. Gemme; R. Geng; E. Genin; A. Gennai; L. A. Gergely; S. Ghosh; J. A. Giaime; S. Giampanis; K. D. Giardina; A. Giazotto; S. Gil; C. Gill; J. Gleason; E. Goetz; L. M. Goggin; G. Gonzalez; M. L. Gorodetsky; S. Gossler; R. Gouaty; C. Graef; P. B. Graff; M. Granata; A. Grant; S. Gras; C. Gray; N. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; C. Greverie; R. Grosso; H. Grote; S. Grunewald; G. M. Guidi; C. Guido; R. Gupta; E. K. Gustafson; R. Gustafson; T. Ha; J. M. Hallam; D. Hammer; G. Hammond; J. Hanks; C. Hanna; J. Hanson; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; M. T. Hartman; K. Haughian; K. Hayama; J. -F. Hayau; J. Heefner; A. Heidmann; M. C. Heintze; H. Heitmann; P. Hello; M. A. Hendry; I. S. Heng; A. W. Heptonstall; V. Herrera; M. Hewitson; S. Hild; D. Hoak; K. A. Hodge; K. Holt; M. Holtrop; T. Hong; S. Hooper; D. J. Hosken; J. Hough; E. J. Howell; B. Hughey; S. Husa; S. H. Huttner; T. Huynh-Dinh; D. R. Ingram; R. Inta; T. Isogai; A. Ivanov; K. Izumi; M. Jacobson; E. James; Y. J. Jang; P. Jaranowski; E. Jesse; W. W. Johnson; D. I. Jones; G. Jones; R. Jones; L. Ju; P. Kalmus; V. Kalogera; S. Kandhasamy; G. Kang; J. B. Kanner; R. Kasturi; E. Katsavounidis; W. Katzman; H. Kaufer; K. Kawabe; S. Kawamura; F. Kawazoe; D. Kelley; W. Kells; D. G. Keppel; Z. Keresztes; A. Khalaidovski; F. Y. Khalili; E. A. Khazanov; B. Kim; C. Kim; H. Kim; K. Kim; N. Kim; Y. -M. Kim; P. J. King; D. L. Kinzel; J. S. Kissel; S. Klimenko; K. Kokeyama; V. Kondrashov; S. Koranda; W. Z. Korth; I. Kowalska

    2012-04-25T23:59:59.000Z

    We present the results of a weakly modeled burst search for gravitational waves from mergers of non-spinning intermediate mass black holes (IMBH) in the total mass range 100--450 solar masses and with the component mass ratios between 1:1 and 4:1. The search was conducted on data collected by the LIGO and Virgo detectors between November of 2005 and October of 2007. No plausible signals were observed by the search which constrains the astrophysical rates of the IMBH mergers as a function of the component masses. In the most efficiently detected bin centered on 88+88 solar masses, for non-spinning sources, the rate density upper limit is 0.13 per Mpc^3 per Myr at the 90% confidence level.

  12. A Hamiltonian Approach to the Mass of Isolated Black Holes

    E-Print Network [OSTI]

    Christopher Beetle; Stephen Fairhurst

    1999-08-01T23:59:59.000Z

    Boundary conditions defining a non-rotating isolated horizon are given in Einstein-Maxwell theory. A spacetime representing a black hole which itself is in equilibrium but whose exterior contains radiation admits such a horizon. Inspired by Hamiltonian mechanics, a (quasi-)local definition of isolated horizon mass is formulated. Although its definition does not refer to infinity, this mass takes the standard value in a Reissner-Nordstrom solution. Furthermore, under certain technical assumptions, the mass of an isolated horizon is shown to equal the future limit of the Bondi energy.

  13. Simulating the growth of Intermediate Mass Black Holes

    E-Print Network [OSTI]

    Pacucci, Fabio

    2015-01-01T23:59:59.000Z

    Theoretical models predict that a population of Intermediate Mass Black Holes (IMBHs) of mass $M_\\bullet \\approx 10^{4-5} \\, \\mathrm{M_{\\odot}}$ might form at high ($z > 10$) redshift by different processes. Such objects would represent the seeds out of which $z > 6$ Super-Massive Black Holes (SMBHs) grow. We numerically investigate the radiation-hydrodynamic evolution governing the growth of such seeds via accretion of primordial gas within their parent dark matter halo of virial temperature $T_{vir} \\sim 10^4 \\, \\mathrm{K}$. We find that the accretion onto a Direct Collapse Black Hole (DCBH) of initial mass $M_0=10^5 \\, \\mathrm{M_{\\odot}}$ occurs at an average rate $\\dot{M}_{\\bullet} \\simeq 1.35 \\, \\dot{M}_{Edd} \\simeq 0.1 \\, \\mathrm{M_{\\odot} \\, yr^{-1}}$, is intermittent (duty-cycle $ emits on average at super-Eddington luminosities, progressively becoming more luminous as the density of the inner mass shells, directly feeding the central obj...

  14. Recoils from unequal-mass, precessing black-hole binaries: The Intermediate Mass Ratio Regime

    E-Print Network [OSTI]

    Zlochower, Yosef

    2015-01-01T23:59:59.000Z

    We revisit the modeling of the properties of the black-hole remnant resulting the merger of a black-hole binary as a function of the parameters of the binary. We provide a set of empirical formulas for the final mass, spin and recoil velocity of the final black hole as a function of the mass ratio and individual spins of the progenitor. In order to determine the fitting coefficients for these formulas, we perform a set of 126 new numerical evolutions of precessing, unequal-mass black-hole binaries, and fit to the resulting remnant mass, spin, and recoil. In order to reduce the complexity of the analysis, we chose configurations that have one of the black holes spinning, with dimensionless spin alpha=0.8, at different angles with respect to the orbital angular momentum, and the other non-spinning. In addition to evolving families of binaries with different spin-inclination angles, we also evolved binaries with mass ratios as small as q=1/6. We use the resulting empirical formulas to predict the probabilities o...

  15. The structure of the carbon black flame

    E-Print Network [OSTI]

    Anderson, W. Kermi

    1945-01-01T23:59:59.000Z

    BLACK FLAME A Dissertation By William Kermit Anderson THEHSR UCOF 120925 TNLKMDiserstsKa aony WHR1mo WdpvmlcyfEyS lnR1 R1WvpS 1nS nvfyARyfh vySS Rm R1y SyuyoWc nvfnunfHWcS Wvf fybWoRgyvRS l1m dmmbyoWRyf Rm gWpy R1nS lmop bmSSnAcy. xbydnWc R1Wvp...S Woy fHy Rm R1y PmccmlnvE gygAyoS mP R1y. SRWPP mP R1y TEondHcRHoWc Wvf tyd1WvndWc NmccyEy mP ayqWS. am eo. joyf D. :yvSyv Pmo Ryd1vndWc 1ycb Wvf Pmo vHgyomHS SHEEySRnmvS mP uWcHy. am eo. N. N. 9yfEyS Pmo PnvWvdnWc Wnf Wvf yqdych cyvR dmmbyo...

  16. Centennial black carbon turnover observed in a Russia steppe soil

    SciTech Connect (OSTI)

    Hammes, K.; Torn, M.S.; Lapenas, A.G.; Schmidt, M.W.I.

    2008-09-15T23:59:59.000Z

    Black carbon (BC), from incomplete combustion of fuels and biomass, has been considered highly recalcitrant and a substantial sink for carbon dioxide. Recent studies have shown that BC can be degraded in soils. We use two soils with very low spatial variability sampled 100 years apart in a Russian steppe preserve to generate the first whole-profile estimate of BC stocks and turnover in the field. Quantities of fire residues in soil changed significantly over a century. Black carbon stock was 2.5 kg m{sup -2}, or about 7-10% of total organic C in 1900. With cessation of biomass burning, BC stocks decreased 25% over a century, which translates into a centennial soil BC turnover (293 years best estimate; range 182-541 years), much faster than so-called inert or passive carbon in ecosystem models. The turnover time presented here is for loss by all processes, namely decomposition, leaching, and erosion, although the latter two were probably insignificant in this case. Notably, at both time points, the peak BC stock was below 30 cm, a depth interval, which is not typically accounted for. Also, the quality of the fire residues changed with time, as indicated by the use benzene poly carboxylic acids (BPCA) as molecular markers. The proportions of less-condensed (and thus more easily degradable) BC structures decreased, whereas the highly condensed (and more recalcitrant) BC structures survived unchanged over the 100-year period. Our results show that BC cannot be assumed chemically recalcitrant in all soils, and other explanations for very old soil carbon are needed.

  17. Multi-Proxy Approach on Black Carbon Characterization and Combustion Products Source Discrimination in Environmental Media 

    E-Print Network [OSTI]

    Kuo, Li-Jung

    2011-02-22T23:59:59.000Z

    Environmental applications of pyrogenic carbon, aka black carbon (BC), have been hampered due to the poor characterization and quantification of environmental BC. This dissertation was dedicated to the better characterization ...

  18. Climate Impacts of Atmospheric Sulfate and Black Carbon Aerosols

    SciTech Connect (OSTI)

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

    2008-09-19T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    B. Aschenbach

    2007-10-18T23:59:59.000Z

    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.

  20. CONSTRAINING INTERMEDIATE-MASS BLACK HOLES IN GLOBULAR CLUSTERS

    SciTech Connect (OSTI)

    Umbreit, Stefan; Rasio, Frederic A., E-mail: s-umbreit@northwestern.edu, E-mail: rasio@northwestern.edu [Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA) and Department of Physics and Astronomy, Northwestern University, 2145 Sheridan Rd, Evanston, IL 60208 (United States)

    2013-05-01T23:59:59.000Z

    Decades after the first predictions of intermediate-mass black holes (IMBHs) in globular clusters (GCs) there is still no unambiguous observational evidence for their existence. The most promising signatures for IMBHs are found in the cores of GCs, where the evidence now comes from the stellar velocity distribution, the surface density profile, and, for very deep observations, the mass-segregation profile near the cluster center. However, interpretation of the data, and, in particular, constraints on central IMBH masses, require the use of detailed cluster dynamical models. Here we present results from Monte Carlo cluster simulations of GCs that harbor IMBHs. As an example of application, we compare velocity dispersion, surface brightness and mass-segregation profiles with observations of the GC M10, and constrain the mass of a possible central IMBH in this cluster. We find that, although M10 does not seem to possess a cuspy surface density profile, the presence of an IMBH with a mass up to 0.75% of the total cluster mass, corresponding to about 600 M{sub Sun }, cannot be excluded. This is also in agreement with the surface brightness profile, although we find it to be less constraining, as it is dominated by the light of giants, causing it to fluctuate significantly. We also find that the mass-segregation profile cannot be used to discriminate between models with and without IMBH. The reason is that M10 is not yet dynamically evolved enough for the quenching of mass segregation to take effect. Finally, detecting a velocity dispersion cusp in clusters with central densities as low as in M10 is extremely challenging, and has to rely on only 20-40 bright stars. It is only when stars with masses down to 0.3 M{sub Sun} are included that the velocity cusp is sampled close enough to the IMBH for a significant increase above the core velocity dispersion to become detectable.

  1. Black carbon radiative heating effects on cloud microphysics and implications for the aerosol indirect

    E-Print Network [OSTI]

    Nenes, Athanasios

    thought. 1. Introduction Black Carbon (BC) has important effects on climate, owing to its ability of Technology, Pasadena, California, 91125, USA Abstract. This work examines the effect of black carbon (BC) radiative heating on cloud droplet formation. Changes in cloud droplet concentration and cloud albedo due

  2. Effect of composite microstructure on electrical and mechanical properties of poly(vinyl acetate) composites with carbon black and clay. 

    E-Print Network [OSTI]

    Miriyala, Sethu M.

    2009-05-15T23:59:59.000Z

    -based case, fully solvated polymer results in a random dispersion of carbon black. The segregated network composite also shows significant improvement in both electrical conductivity and storage modulus with low carbon black loading, while the solution...

  3. Running-mass inflation model and primordial black holes

    SciTech Connect (OSTI)

    Drees, Manuel; Erfani, Encieh, E-mail: drees@th.physik.uni-bonn.de, E-mail: erfani@th.physik.uni-bonn.de [Physikalisches Institut and Bethe Center for Theoretical Physics, Universität Bonn, Nussallee 12, 53115 Bonn (Germany)

    2011-04-01T23:59:59.000Z

    We revisit the question whether the running-mass inflation model allows the formation of Primordial Black Holes (PBHs) that are sufficiently long-lived to serve as candidates for Dark Matter. We incorporate recent cosmological data, including the WMAP 7-year results. Moreover, we include ''the running of the running'' of the spectral index of the power spectrum, as well as the renormalization group ''running of the running'' of the inflaton mass term. Our analysis indicates that formation of sufficiently heavy, and hence long-lived, PBHs still remains possible in this scenario. As a by-product, we show that the additional term in the inflaton potential still does not allow significant negative running of the spectral index.

  4. THE RELATION BETWEEN BLACK HOLE MASS AND HOST SPHEROID STELLAR MASS OUT TO z {approx} 2

    SciTech Connect (OSTI)

    Bennert, Vardha N.; Auger, Matthew W.; Treu, Tommaso [Department of Physics, University of California, Santa Barbara, CA 93106 (United States); Woo, Jong-Hak [Astronomy Program, Department of Physics and Astronomy, Seoul National University (Korea, Republic of); Malkan, Matthew A., E-mail: vbennert@calpoly.edu, E-mail: tt@physics.ucsb.edu, E-mail: mauger@ast.cam.ac.uk, E-mail: woo@astro.snu.ac.kr, E-mail: malkan@astro.ucla.edu [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095 (United States)

    2011-12-01T23:59:59.000Z

    We combine Hubble Space Telescope images from the Great Observatories Origins Deep Survey with archival Very Large Telescope and Keck spectra of a sample of 11 X-ray-selected broad-line active galactic nuclei in the redshift range 1 < z < 2 to study the black-hole-mass-stellar-mass relation out to a look-back time of 10 Gyr. Stellar masses of the spheroidal component (M{sub sph,*}) are derived from multi-filter surface photometry. Black hole masses (M{sub BH}) are estimated from the width of the broad Mg II emission line and the 3000 A nuclear luminosity. Comparing with a uniformly measured local sample and taking into account selection effects, we find evolution in the form M{sub BH}/M{sub sph,*}{proportional_to}(1 + z){sup 1.96{+-}}0{sup .55}, in agreement with our earlier studies based on spheroid luminosity. However, this result is more accurate because it does not require a correction for luminosity evolution and therefore avoids the related and dominant systematic uncertainty. We also measure total stellar masses (M{sub host,*}). Combining our sample with data from the literature, we find M{sub BH}/M{sub host,*}{proportional_to}(1 + z){sup 1.15{+-}0.15}, consistent with the hypothesis that black holes (in the range M{sub BH} {approx} 10{sup 8-9} M{sub Sun }) pre-date the formation of their host galaxies. Roughly, one-third of our objects reside in spiral galaxies; none of the host galaxies reveal signs of interaction or major merger activity. Combined with the slower evolution in host stellar masses compared to spheroid stellar masses, our results indicate that secular evolution or minor mergers play a non-negligible role in growing both BHs and spheroids.

  5. Black carbon in the Gulf of Maine : new insights into inputs and cycling of combustion-derived organic carbon

    E-Print Network [OSTI]

    Flores Cervantes, Déborah Xanat, 1978-

    2008-01-01T23:59:59.000Z

    Emissions of black carbon (BC), the soot and char formed during incomplete combustion of fossil and biomass fuels, have increased over the last century and are estimated to be between 8 and 270 Tg BC/yr. BC may affect ...

  6. Stellar and Intermediate-Mass Black Holes in the Milky Way and Nearby Galaxies

    SciTech Connect (OSTI)

    Irwin, Jimmy [Department of Physics and Astronomy, University of Alabama, Box 870324, Tuscaloosa, AL 35487-0324 (United States)

    2010-08-09T23:59:59.000Z

    With the advent of high resolution X-ray telescopes, the ability to identify extragalactic black holes has greatly enhanced our understanding of massive compact objects, as we are no longer limited to the rather meager Milky Way black hole population. The greatly increased numbers have opened up opportunities to find new modes of compact object accretion and potentially long-sought evidence for intermediate-mass black holes. In this lecture series, the current state of knowledge of stellar- and intermediate-mass black holes is reviewed, particularly in regards to black hole populations in external galaxies.

  7. Observable signatures of extreme mass-ratio inspiral black hole binaries embedded in thin accretion disks

    E-Print Network [OSTI]

    Kocsis, Bence

    We examine the electromagnetic and gravitational wave (GW) signatures of stellar-mass compact objects (COs) spiraling into a supermassive black hole (extreme mass-ratio inspirals), embedded in a thin, radiation-pressure ...

  8. Multifunctional Superhydrophobic Polymer/Carbon Nanocomposites: Graphene, Carbon Nanotubes, or Carbon Black?

    E-Print Network [OSTI]

    Daraio, Chiara

    Multifunctional Superhydrophobic Polymer/Carbon Nanocomposites: Graphene, Carbon Nanotubes, Switzerland *S Supporting Information ABSTRACT: Superhydrophobic surfaces resisting water penetration fabrication of highly electrically conductive, polymer-based superhydrophobic coatings, with impressive

  9. Measured Black Carbon Deposition on the Sierra Nevada Snow Pack and Implication for Snow Pack Retreat

    SciTech Connect (OSTI)

    Hadley, O.L.; Corrigan, C.E.; Kirchstetter, T.W.; Cliff, S.S.; Ramanathan, V.

    2010-01-12T23:59:59.000Z

    Modeling studies show that the darkening of snow and ice by black carbon deposition is a major factor for the rapid disappearance of arctic sea ice, mountain glaciers and snow packs. This study provides one of the first direct measurements for the efficient removal of black carbon from the atmosphere by snow and its subsequent deposition to the snow packs of California. The early melting of the snow packs in the Sierras is one of the contributing factors to the severe water problems in California. BC concentrations in falling snow were measured at two mountain locations and in rain at a coastal site. All three stations reveal large BC concentrations in precipitation, ranging from 1.7 ng/g to 12.9 ng/g. The BC concentrations in the air after the snow fall were negligible suggesting an extremely efficient removal of BC by snow. The data suggest that below cloud scavenging, rather than ice nuclei, was the dominant source of BC in the snow. A five-year comparison of BC, dust, and total fine aerosol mass concentrations at multiple sites reveals that the measurements made at the sampling sites were representative of large scale deposition in the Sierra Nevada. The relative concentration of iron and calcium in the mountain aerosol indicates that one-quarter to one-third of the BC may have been transported from Asia.

  10. RETENTION OF STELLAR-MASS BLACK HOLES IN GLOBULAR CLUSTERS

    SciTech Connect (OSTI)

    Morscher, Meagan; Umbreit, Stefan; Farr, Will M.; Rasio, Frederic A., E-mail: m.morscher@u.northwestern.edu, E-mail: s-umbreit@northwestern.edu, E-mail: w-farr@northwestern.edu, E-mail: rasio@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)

    2013-01-20T23:59:59.000Z

    Globular clusters should be born with significant numbers of stellar-mass black holes (BHs). It has been thought for two decades that very few of these BHs could be retained through the cluster lifetime. With masses {approx}10 M{sub Sun }, BHs are {approx}20 times more massive than an average cluster star. They segregate into the cluster core, where they may eventually decouple from the remainder of the cluster. The small-N core then evaporates on a short timescale. This is the so-called Spitzer instability. Here we present the results of a full dynamical simulation of a globular cluster containing many stellar-mass BHs with a realistic mass spectrum. Our Monte Carlo simulation code includes detailed treatments of all relevant stellar evolution and dynamical processes. Our main finding is that old globular clusters could still contain many BHs at present. In our simulation, we find no evidence for the Spitzer instability. Instead, most of the BHs remain well mixed with the rest of the cluster, with only the innermost few tens of BHs segregating significantly. Over the 12 Gyr evolution, fewer than half of the BHs are dynamically ejected through strong binary interactions in the cluster core. The presence of BHs leads to long-term heating of the cluster, ultimately producing a core radius on the high end of the distribution for Milky Way globular clusters (and those of other galaxies). A crude extrapolation from our model suggests that the BH-BH merger rate from globular clusters could be comparable to the rate in the field.

  11. A modeling study on the climate impacts of black carbon aerosols

    E-Print Network [OSTI]

    Wang, Chien.

    The role of black carbon (BC) aerosols in climate change is important because of its strong capability in causing extinction of solar radiation. A three-dimensional interactive aerosol-climate model has been used to study ...

  12. Size and shape of crystallites and internal stresses in carbon blacks T. Ungara,*, J. Gubiczab

    E-Print Network [OSTI]

    Gubicza, Jenő

    is generally used as a filler in rubber production to modify the mechanical properties of the tire. Although sites present on the surface determine reinfor- cing properties of carbon black in rubber [7]. Energy

  13. Design of a bench-scale apparatus for processing carbon black derived from scrap tires

    E-Print Network [OSTI]

    Woodrow, Philip Travis

    1996-01-01T23:59:59.000Z

    The focus of this work is to design a bench-scale apparatus, for laboratory applications, that will perform solid processing operations for carbon black obtained through the thermal catalytic depolymerization of scrap tires. These operations...

  14. Selection and Characterization of Carbon Black and Surfactants for Development of Small Scale Uranium Oxicarbide Kernels

    SciTech Connect (OSTI)

    Contescu, Cristian I [ORNL

    2006-01-01T23:59:59.000Z

    This report supports the effort for development of small scale fabrication of UCO (a mixture of UO{sub 2} and UC{sub 2}) fuel kernels for the generation IV high temperature gas reactor program. In particular, it is focused on optimization of dispersion conditions of carbon black in the broths from which carbon-containing (UO{sub 2} {center_dot} H{sub 2}O + C) gel spheres are prepared by internal gelation. The broth results from mixing a hexamethylenetetramine (HMTA) and urea solution with an acid-deficient uranyl nitrate (ADUN) solution. Carbon black, which is previously added to one or other of the components, must stay dispersed during gelation. The report provides a detailed description of characterization efforts and results, aimed at identification and testing carbon black and surfactant combinations that would produce stable dispersions, with carbon particle sizes below 1 {micro}m, in aqueous HMTA/urea and ADUN solutions. A battery of characterization methods was used to identify the properties affecting the water dispersability of carbon blacks, such as surface area, aggregate morphology, volatile content, and, most importantly, surface chemistry. The report introduces the basic principles for each physical or chemical method of carbon black characterization, lists the results obtained, and underlines cross-correlations between methods. Particular attention is given to a newly developed method for characterization of surface chemical groups on carbons in terms of their acid-base properties (pK{sub a} spectra) based on potentiometric titration. Fourier-transform infrared (FTIR) spectroscopy was used to confirm the identity of surfactants, both ionic and non-ionic. In addition, background information on carbon black properties and the mechanism by which surfactants disperse carbon black in water is also provided. A list of main physical and chemical properties characterized, samples analyzed, and results obtained, as well as information on the desired trend or range of values generally associated with better dispersability, is provided in the Appendix. Special attention was given to characterization of several surface-modified carbon blacks produced by Cabot Corporation through proprietary diazonium salts chemistry. As demonstrated in the report, these advanced carbons offer many advantages over traditional dispersions. They disperse very easily, do not require intensive mechanical shearing or sonication, and the particle size of the dispersed carbon black aggregates is in the target range of 0.15-0.20 {micro}m. The dispersions in water and HMTA/urea solutions are stable for at least 30 days; in conditions of simulated broth, the dispersions are stable for at least 6 hours. It is proposed that the optimization of the carbon black dispersing process is possible by replacing traditional carbon blacks and surfactants with surface-modified carbon blacks having suitable chemical groups attached on their surface. It is recognized that the method advanced in this report for optimizing the carbon black dispersion process is based on a limited number of tests made in aqueous and simulated broth conditions. The findings were corroborated by a limited number of tests carried out with ADUN solutions by the Nuclear Science and Technology Division at Oak Ridge National Laboratory (ORNL). More work is necessary, however, to confirm the overall recommendation based on the findings discussed in this report: namely, that the use of surface-modified carbon blacks in the uranium-containing broth will not adversely impact the chemistry of the gelation process, and that high quality uranium oxicarbide (UCO) kernels will be produced after calcination.

  15. Black carbon aerosols and the third polar ice cap

    SciTech Connect (OSTI)

    Menon, Surabi; Koch, Dorothy; Beig, Gufran; Sahu, Saroj; Fasullo, John; Orlikowski, Daniel

    2010-04-15T23:59:59.000Z

    Recent thinning of glaciers over the Himalayas (sometimes referred to as the third polar region) have raised concern on future water supplies since these glaciers supply water to large river systems that support millions of people inhabiting the surrounding areas. Black carbon (BC) aerosols, released from incomplete combustion, have been increasingly implicated as causing large changes in the hydrology and radiative forcing over Asia and its deposition on snow is thought to increase snow melt. In India BC emissions from biofuel combustion is highly prevalent and compared to other regions, BC aerosol amounts are high. Here, we quantify the impact of BC aerosols on snow cover and precipitation from 1990 to 2010 over the Indian subcontinental region using two different BC emission inventories. New estimates indicate that Indian BC emissions from coal and biofuel are large and transport is expected to expand rapidly in coming years. We show that over the Himalayas, from 1990 to 2000, simulated snow/ice cover decreases by {approx}0.9% due to aerosols. The contribution of the enhanced Indian BC to this decline is {approx}36%, similar to that simulated for 2000 to 2010. Spatial patterns of modeled changes in snow cover and precipitation are similar to observations (from 1990 to 2000), and are mainly obtained with the newer BC estimates.

  16. Stability of black carbon in soils across a climatic gradient Chih-Hsin Cheng,1,2

    E-Print Network [OSTI]

    Lehmann, Johannes

    5 March 2008; published 4 June 2008. [1] The recalcitrant properties of black carbon (BC) grant carbon dioxide in soils [Lehmann et al., 2006; Lehmann, 2007a, 2007b]. [3] However, the notionStability of black carbon in soils across a climatic gradient Chih-Hsin Cheng,1,2 Johannes Lehmann

  17. Black Carbon’s Properties and Role in the Environment: A Comprehensive Review

    E-Print Network [OSTI]

    Shrestha, Gyami

    2010-01-01T23:59:59.000Z

    carbon has a high carbon sequestration potential due to itsin soil can lead to sustainable carbon sequestration.process takes carbon sequestration from afforestation a step

  18. Long-term Black Carbon Dynamics in Cultivated Soil

    SciTech Connect (OSTI)

    Nguyen, Binh T.; Lehmann, Johannes C.; Kinyangi, James; Smernik, Ron; Riha, Susan J.; Engelhard, Mark H.

    2008-07-01T23:59:59.000Z

    Black carbon (BC) is a quantitatively important C pool in the global carbon cycle due to its relative recalcitrance against decay compared with other C pools. However, how rapidly BC is oxidized and in what way the molecular structure changes during decomposition over decadal time scales, is largely unknown. In the present study, the long-term dynamics in quality and quantity of BC were investigated in cultivated soil using X-ray Photoelectron Spectroscopy (XPS), Fourier-Transform Infrared (FTIR) and Nuclear Magnetic Resonance (NMR) techniques. BC particles, obtained from soil samples at 8 conversion ages stretching over 100 years and from a forest soil sample from Kenya, were manually picked under a light microscope for characterization and quantification. BC contents rapidly decreased from 12.7 to 3.8 mg C g?ą soil during the first 30 years since conversion, after which they slowly decreased to a steady state at 3.51 mg C g ?ąsoil. BC-derived C losses over 100 years were estimated at 6000 kg C ha?ą to a depth of 0.1 m. The initial rapid changes in BC stocks resulted in a mean residence time of only around 8.3 years, which was likely a function of both decomposition as well as transport processes. The molecular properties of BC changed more rapidly on surfaces than in the interior of BC particles and more rapidly during the first 30 years than during the following 70 years. The Oc/C ratios (Oc is O bound to C) and carbonyl groups (C=O) increased over time by 133 and 192 %, respectively, indicating oxidation was an important degradation process controlling BC quality. Al, Si, polysaccharides, and to a lesser extent Fe were rapidly adsorbed on BC particle surfaces within the first few years after BC deposition to soil. The protection by physical and chemical stabilization was apparently sufficient to not only minimize decomposition below detection between 30 and 100 years after deposition, but also physical export by erosion and vertical transport below 0.1 m.

  19. Linearity of Climate Response to Increases in Black Carbon Aerosols

    SciTech Connect (OSTI)

    Mahajan, Salil [ORNL; Evans, Katherine J [ORNL; Hack, James J [ORNL; Truesdale, John [National Center for Atmospheric Research (NCAR)

    2013-01-01T23:59:59.000Z

    The impact of absorbing aerosols on global climate are not completely understood. Here, we present results of idealized experiments conducted with the Community Atmosphere Model (CAM4) coupled to a slab ocean model (CAM4-SOM) to simulate the climate response to increases in tropospheric black carbon aerosols (BC) by direct and semi-direct effects. CAM4-SOM was forced with 0, 1x, 2x, 5x and 10x an estimate of the present day concentration of BC while maintaining their estimated present day global spatial and vertical distribution. The top of the atmosphere (TOA) radiative forcing of BC in these experiments is positive (warming) and increases linearly as the BC burden increases. The total semi-direct effect for the 1x experiment is positive but becomes increasingly negative for higher BC concentrations. The global average surface temperature response is found to be a linear function of the TOA radiative forcing. The climate sensitivity to BC from these experiments is estimated to be 0.42 K $\\textnormal W^{-1} m^{2}$ when the semi-direct effects are accounted for and 0.22 K $\\textnormal W^{-1} m^{2}$ with only the direct effects considered. Global average precipitation decreases linearly as BC increases, with a precipitation sensitivity to atmospheric absorption of 0.4 $\\%$ $\\textnormal W^{-1} \\textnormal m^{2}$ . The hemispheric asymmetry of BC also causes an increase in southward cross-equatorial heat transport and a resulting northward shift of the inter-tropical convergence zone in the simulations at a rate of 4$^{\\circ}$N $\\textnormal PW^{-1}$. Global average mid- and high-level clouds decrease, whereas the low-level clouds increase linearly with BC. The increase in marine stratocumulus cloud fraction over the south tropical Atlantic is caused by increased BC-induced diabatic heating of the free troposphere.

  20. Near-Critical Gravitational Collapse and the Initial Mass Function of Primordial Black Holes

    E-Print Network [OSTI]

    J. C. Niemeyer; K. Jedamzik

    1998-05-13T23:59:59.000Z

    The recent discovery of critical phenomena arising in gravitational collapse near the threshold of black hole formation is used to estimate the initial mass function of primordial black holes (PBHs). It is argued that the universal scaling relation between black hole mass and initial perturbation found for a variety of collapsing space-times also applies to PBH formation, indicating the possibility of the formation of PBHs with masses much smaller than one horizon mass. Owing to the natural fine-tuning of initial conditions by the exponential decline of the probability distribution for primordial density fluctuations, sub-horizon mass PBHs are expected to form at all epochs. This result suggests that the constraints on the primordial fluctuation spectrum based on the abundance of PBHs at different mass scales may have to be revisited.

  1. Natural Oxidation of Black Carbon in Soils: Changes in Molecular...

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

    factors affect BC oxidation. Black C was collected from 11 historical charcoal blast furnace sites with a geographic distribution from Quebec, Canada, to Georgia, USA, and...

  2. Department of Earth Sciences www.rhul.ac.uk/earthsciences Page 1 of 1 Does black carbon and humic materials in snow and ice decay?

    E-Print Network [OSTI]

    Sheldon, Nathan D.

    the and optics properties of black carbon change. As little as 10 ng of Black carbon in 1 g of snow can cause 1 of two more effective than carbon dioxide in changing global air temperatures.2 The successful candidateDepartment of Earth Sciences www.rhul.ac.uk/earthsciences Page 1 of 1 Does black carbon and humic

  3. The Effects of Black Carbon and Sulfate Aerosols in ChinaRegions on East Asia Monsoons

    SciTech Connect (OSTI)

    Yang, Bai [ORNL; Liu, Yu [Chinese Academy of Meteorological Sciences, Beijing, China; Sun, Jiaren [South China Institute of Environmental Sciences, Guangzhou, China

    2009-01-01T23:59:59.000Z

    In this paper we examine the direct effects of sulfate and black carbon aerosols in China on East Asia monsoons and its precipitation processes by using the CAM3.0 model. It is demonstrated that sulfate and black carbon aerosols in China both have the effects to weaken East Asia monsoons in both summer and winter seasons. However, they certainly differ from each other in affecting vertical structures of temperature and atmospheric circulations. Their differences are expected because of their distinct optical properties, i.e., scattering vs. absorbing. Even for a single type of aerosol, its effects on temperature structures and atmospheric circulations are largely season-dependent. Applications of T-test on our results indicate that forcing from black carbon aerosols over China is relatively weak and limited. It is also evident from our results that the effects of synthetic aerosols (sulfate and black carbon together) on monsoons are not simply a linear summation between these two types of aerosols. Instead, they are determined by their integrated optical properties. Synthetic aerosols to a large degree resemble effects of sulfate aerosols. This implies a likely scattering property for the integration of black carbon and sulfate aerosols in China.

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

    E-Print Network [OSTI]

    Scott Fraser; Douglas M. Eardley

    2014-09-04T23:59:59.000Z

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

  5. An Index-Based Approach to Assessing Recalcitrance and Soil Carbon Sequestration Potential of Engineered Black Carbons (Biochars)

    SciTech Connect (OSTI)

    Harvey, Omar R.; Kuo, Li-Jung; Zimmerman, Andrew R.; Louchouarn, Patrick; Amonette, James E.; Herbert, Bruce

    2012-01-10T23:59:59.000Z

    The ability of engineered black carbons (or biochars) to resist abiotic and, or biotic degradation (herein referred to as recalcitrance) is crucial to their successful deployment as a soil carbon sequestration strategy. A new recalcitrance index, the R{sub 50}, for assessing biochar quality for carbon sequestration is proposed. The R{sub 50} is based on the relative thermal stability of a given biochar to that of graphite and was developed and evaluated with a variety of biochars (n = 59), and soot-like black carbons. Comparison of R{sub 50}, with biochar physicochemical properties and biochar-C mineralization revealed the existence of a quantifiable relationship between R{sub 50} and biochar recalcitrance. As presented here, the R{sub 50} is immediately applicable to pre-land application screening of biochars into Class A (R{sub 50} {>=} 0.70), Class B (0.50 {<=} R{sub 50} < 0.70) or Class C (R{sub 50} < 0.50) recalcitrance/carbon sequestration classes. Class A and Class C biochars would have carbon sequestration potential comparable to soot/graphite and uncharred plant biomass, respectively, while Class B biochars would have intermediate carbon sequestration potential. We believe that the coupling of the R{sub 50}, to an index-based degradation, and an economic model could provide a suitable framework in which to comprehensively assess soil carbon sequestration in biochars.

  6. Carbon black: A low cost colloidal additive for controlling gas-migration in cement slurries

    SciTech Connect (OSTI)

    Calloni, G.; Moroni, N.; Miano, F.

    1995-11-01T23:59:59.000Z

    The effect of different additives on the permeability of cement slurries to formation gas has been studied with the aid of a gas flow apparatus. The performance of two commercial additives (polymer latex and silica fume) has been compared to that of a novel additive (carbon black) that has been developed in the authors laboratories with the aim of simplifying the cement slurry composition and reducing field operational costs. Data on the thickening time, fluid loss, rheology and compressive strength are also presented to provide a clear picture of the potential of carbon black as a substitute for silica fume and polymer latex in some field applications. Finally, the paper describes the results of a field application using carbon black as a gas-block additive in the cement slurry.

  7. Bounding the Role of Black Carbon in the Climate System: A Scientific Assessment

    SciTech Connect (OSTI)

    Bond, Tami C.; Doherty, Sarah J.; Fahey, D. W.; Forster, Piers; Berntsen, T.; DeAngelo, B. J.; Flanner, M. G.; Ghan, Steven J.; Karcher, B.; Koch, Dorothy; Kinne, Stefan; Kondo, Yutaka; Quinn, P. K.; Sarofim, Marcus; Schultz, Martin; Schulz, M.; Venkataraman, C.; Zhang, Hua; Zhang, Shiqiu; Bellouin, N.; Guttikunda, S. K.; Hopke, P. K.; Jacobson, M. Z.; Kaiser, J. W.; Klimont, Z.; Lohmann, U.; Schwarz, Joshua P.; Shindell, Drew; Storelvmo, Trude; Warren, Stephen G.; Zender, C. S.

    2013-06-06T23:59:59.000Z

    Black carbon aerosol plays a unique and important role in Earth’s climate system. Black carbon is a type of carbonaceous material with a unique combination of physical properties. Predominant sources are combustion related; namely, fossil fuels for transportation, solid fuels for industrial and residential uses, and open burning of biomass. Total global emissions of black carbon using bottom-up inventory methods are 7500 Gg yr-1 in the year 2000 with an uncertainty range of 2000 to 29000. This assessment provides an evaluation of black-carbon climate forcing that is comprehensive in its inclusion of all known and relevant processes and that is quantitative in providing best estimates and uncertainties of the main forcing terms: direct solar absorption, influence on liquid, mixed-phase, and ice clouds, and deposition on snow and ice. These effects are calculated with models, but when possible, they are evaluated with both microphysical measurements and field observations. Global atmospheric absorption attributable to black carbon is too low in many models, and should be increased by about about 60%. After this scaling, the best estimate for the industrial-era (1750 to 2005) direct radiative forcing of black carbon is +0.43 W m-2 with 90% uncertainty bounds of (+0.17, +0.68) W m-2. Total direct forcing by all black carbon sources in the present day is estimated as +0.49 (+0.20, +0.76) W m-2. Direct radiative forcing alone does not capture important rapid adjustment mechanisms. A framework is described and used for quantifying climate forcings and their rapid responses and feedbacks. The best estimate of industrial-era (1750 to 2005) climate forcing of black carbon through all forcing mechanisms is +0.77 W m-2 with 90% uncertainty bounds of +-0.06 to +1.53 W m-2. Thus, there is a 96% probability that black carbon emissions, independent of co-emitted species, have a positive forcing and warm the climate. With a value of +0.77 W m-2, black carbon is likely the second most important individual climate-forcing agent in the industrial era, following carbon dioxide. Sources that emit black carbon also emit other short- lived species that may either cool or warm climate. Climate forcings from co-emitted species are estimated and used in the framework described herein. When the principal effects of co- emissions, including cooling agents such as sulfur dioxide, are included in net forcing, energy-related sources (fossil-fuel and biofuel) have a net climate forcing of +0.004 (-0.62 to +0.57) W m-2 during the first year after emission. For a few of these sources, such as diesel engines and possibly residential biofuels, warming is strong enough that eliminating all emissions from these sources would reduce net climate forcing (i.e., produce cooling). When open burning emissions, which emit high levels of organic matter, are included in the total, the best estimate of net industrial-era climate forcing by all black- carbon-rich sources becomes slightly negative (-0.08 W m-2 with 90% uncertainty bounds of -1.23 to +0.81 W m-2). The uncertainties in net climate forcing from black-carbon-rich sources are substantial, largely due to lack of knowledge about cloud interactions with both black carbon and co-emitted organic carbon. In prioritizing potential black-carbon mitigation actions, non-science factors, such as technical feasibility, costs, policy design, and implementation feasibility play important roles. The major sources of black carbon are presently in different stages with regard to the feasibility for near-term mitigation. This assessment, by evaluating the large number and complexity of the associated physical and radiative processes in black-carbon climate forcing, sets a baseline from which to improve future climate forcing estimates.

  8. The balance of power: accretion and feedback in stellar mass black holes

    E-Print Network [OSTI]

    Fender, Rob

    2015-01-01T23:59:59.000Z

    In this review we discuss the population of stellar-mass black holes in our galaxy and beyond, which are the extreme endpoints of massive star evolution. In particular we focus on how we can attempt to balance the available accretion energy with feedback to the environment via radiation, jets and winds, considering also possible contributions to the energy balance from black hole spin and advection. We review quantitatively the methods which are used to estimate these quantities, regardless of the details of the astrophysics close to the black hole. Once these methods have been outlined, we work through an outburst of a black hole X-ray binary system, estimating the flow of mass and energy through the different accretion rates and states. While we focus on feedback from stellar mass black holes in X-ray binary systems, we also consider the applicability of what we have learned to supermassive black holes in active galactic nuclei. As an important control sample we also review the coupling between accretion an...

  9. Effect of Temperature on Carbon-Black Agglomeration in Hydrocarbon Liquid with Adsorbed Dispersant

    E-Print Network [OSTI]

    can agglomerate, increasing the viscosity of the oil and significantly diminishing its lubrication performance. The soot can also form a high-viscosity sludge which can also degrade lubricant effectivenessEffect of Temperature on Carbon-Black Agglomeration in Hydrocarbon Liquid with Adsorbed Dispersant

  10. End of the Little Ice Age in the Alps forced by industrial black carbon

    E-Print Network [OSTI]

    Marzeion, Ben

    , Oceanic, and Space Sciences, University of Michigan, Ann Arbor, MI 48109; c Institute of MeteorologyEnd of the Little Ice Age in the Alps forced by industrial black carbon Thomas H. Paintera,1 , Mark and Geophysics, University of Innsbruck, 6020 Innsbruck, Austria; d Air Quality Research Center, University

  11. Mass and Free energy in Thermodynamics of Squashed Kaluza-Klein Black Holes

    E-Print Network [OSTI]

    Yasunari Kurita; Hideki Ishihara

    2007-08-01T23:59:59.000Z

    The Abbott-Deser mass, the Hamiltonian and the Komar mass of the 5-dimensional Kaluza-Klein black hole with squashed horizons take different values. Introducing a new couple of thermodynamic variables for the Komar mass, we show that each mass can be interpreted as a thermodynamic potential with its own natural variables, i.e. all masses are related to each other by the Legendre transformations. It is found that the new variables and the gravitational tension represent the squashing of the outer horizon.

  12. Direct Gravitational Imaging of Intermediate Mass Black Holes in Extragalactic Halos

    E-Print Network [OSTI]

    Kaiki Taro Inoue; Valery Rashkov; Joseph Silk; Piero Madau

    2013-01-22T23:59:59.000Z

    A galaxy halo may contain a large number of intermediate mass black holes (IMBHs) with masses in the range of 10^{2-6} solar mass. We propose to directly detect these IMBHs by observing multiply imaged QSO-galaxy or galaxy-galaxy strong lens systems in the submillimeter bands with high angular resolution. The silhouette of an IMBH in the lensing galaxy halo would appear as either a monopole-like or a dipole-like variation at the scale of the Einstein radius against the Einstein ring of the dust-emitting region surrounding the QSO. We use a particle tagging technique to dynamically populate a Milky Way-sized dark matter halo with black holes, and show that the surface mass density and number density of IMBHs have power-law dependences on the distance from the center of the host halo if smoothed on a scale of ~ 1 kpc. Most of the black holes orbiting close to the center are freely roaming as they have lost their dark matter hosts during infall due to tidal stripping. Next generation submillimeter telescopes with high angular resolution (solar mass in a lensing galaxy that harbours a O(10^9) solar mass supermassive black hole in its nucleus.

  13. The Carbon balance of sorghum from anthesis to black layer

    E-Print Network [OSTI]

    Stahl, Randal Scott

    1986-01-01T23:59:59.000Z

    of low light level. Y was calculated as g the slope of the line between the daily carbon balance parameters dS and dW measured on days 2 and 4, plotted as dW vs dS. iv Each plant was then harvested by organ and oven dried at 80 C for 36 h. The total... Ass imi lati on Chamber Chamber Constr ucti on Air Injection System CO Injection System Ch(mber C02 Concentration Chamber Lighting System Data Acquisition System Calculation of Hourly Carbon Exchange Rates Calculation of Integrated Carbon...

  14. A Reverberation-Based Mass for the Central Black Hole in NGC 4151

    E-Print Network [OSTI]

    Bentz, M C; Cackett, E M; Dietrich, M; Fogel, J K J; Ghosh, H; Horne, K; Kuehn, C; Minezaki, T; Onken, C A; Peterson, B M; Pogge, R W; Pronik, V I; Richstone, D O; Sergeev, S G; Vestergaard, M; Walker, M G; Yoshii, Y; Bentz, Misty C.; Denney, Kelly D.; Cackett, Edward M.; Dietrich, Matthias; Fogel, Jeffrey K. J.; Ghosh, Himel; Horne, Keith; Kuehn, Charles; Minezaki, Takeo; Onken, Christopher A.; Peterson, Bradley M.; Pogge, Richard W.; Pronik, Vladimir I.; Richstone, Douglas O.; Sergeev, Sergey G.; Vestergaard, Marianne; Walker, Matthew G.; Yoshii, Yuzuru

    2006-01-01T23:59:59.000Z

    We have undertaken a new ground-based monitoring campaign to improve the estimates of the mass of the central black hole in NGC 4151. We measure the lag time of the broad H beta line response compared to the optical continuum at 5100 A and find a lag of 6.6 (+1.1/-0.8) days. We combine our data with the recent reanalysis of UV emission lines by Metzroth et al. to calculate a weighted mean of the black hole mass, M_BH = 4.57 (+0.57/-0.47) x 10^7 M_sun. The absolute calibration of the black hole mass is based on normalization of the AGN black hole mass - stellar velocity dispersion (M_BH - sigma_*) relationship to that of quiescent galaxies by Onken et al. The scatter in the M_BH - sigma_* relationship suggests that reverberation-mapping based mass measurements are typically uncertain by a factor of 3-4.

  15. A Reverberation-Based Mass for the Central Black Hole in NGC 4151

    E-Print Network [OSTI]

    Misty C. Bentz; Kelly D. Denney; Edward M. Cackett; Matthias Dietrich; Jeffrey K. J. Fogel; Himel Ghosh; Keith Horne; Charles Kuehn; Takeo Minezaki; Christopher A. Onken; Bradley M. Peterson; Richard W. Pogge; Vladimir I. Pronik; Douglas O. Richstone; Sergey G. Sergeev; Marianne Vestergaard; Matthew G. Walker; Yuzuru Yoshii

    2006-07-05T23:59:59.000Z

    We have undertaken a new ground-based monitoring campaign to improve the estimates of the mass of the central black hole in NGC 4151. We measure the lag time of the broad H beta line response compared to the optical continuum at 5100 A and find a lag of 6.6 (+1.1/-0.8) days. We combine our data with the recent reanalysis of UV emission lines by Metzroth et al. to calculate a weighted mean of the black hole mass, M_BH = 4.57 (+0.57/-0.47) x 10^7 M_sun. The absolute calibration of the black hole mass is based on normalization of the AGN black hole mass - stellar velocity dispersion (M_BH - sigma_*) relationship to that of quiescent galaxies by Onken et al. The scatter in the M_BH - sigma_* relationship suggests that reverberation-mapping based mass measurements are typically uncertain by a factor of 3-4.

  16. Accretion disks around binary black holes of unequal mass: GRMHD simulations of postdecoupling and merger

    E-Print Network [OSTI]

    Roman Gold; Vasileios Paschalidis; Milton Ruiz; Stuart L. Shapiro; Zachariah B. Etienne; Harald P. Pfeiffer

    2014-12-03T23:59:59.000Z

    We report results from simulations in general relativity of magnetized disks accreting onto merging black hole binaries, starting from relaxed disk initial data. The simulations feature an effective, rapid radiative cooling scheme as a limiting case of future treatments with radiative transfer. Here we evolve the systems after binary-disk decoupling through inspiral and merger, and analyze the dependence on the binary mass ratio with $q\\equiv m_{\\rm bh}/M_{\\rm BH}=1,1/2,$ and $1/4$. We find that the luminosity associated with local cooling is larger than the luminosity associated with matter kinetic outflows, while the electromagnetic (Poynting) luminosity associated with bulk transport of magnetic field energy is the smallest. The cooling luminosity around merger is only marginally smaller than that of a single, non-spinning black hole. Incipient jets are launched independently of the mass ratio, while the same initial disk accreting on a single non-spinning black hole does not lead to a jet, as expected. For all mass ratios we see a transient behavior in the collimated, magnetized outflows lasting $2-5 ( M/10^8M_\\odot ) \\rm days$ after merger: the outflows become increasingly magnetically dominated and accelerated to higher velocities, boosting the Poynting luminosity. These sudden changes can alter the electromagnetic emission across the jet and potentially help distinguish mergers of black holes in AGNs from single accreting black holes based on jet morphology alone.

  17. The characteristic black hole mass resulting from direct collapse in the early universe

    E-Print Network [OSTI]

    Latif, M A; Schmidt, W; Niemeyer, J C

    2013-01-01T23:59:59.000Z

    Black holes of a billion solar masses are observed in the infant universe a few hundred million years after the Big Bang. The direct collapse of protogalactic gas clouds in primordial halos with $\\rm T_{vir} \\geq 10^{4} K$ provides the most promising way to assemble massive black holes. In this study, we aim to determine the characteristic mass scale of seed black holes and the time evolution of the accretion rates resulting from the direct collapse model. We explore the formation of supermassive black holes via cosmological large eddy simulations (LES) by employing sink particles and following their evolution for twenty thousand years after the formation of the first sink. As the resulting protostars were shown to have cool atmospheres in the presence of strong accretion, we assume here that UV feedback is negligible during this calculation. We confirm this result in a comparison run without sinks. Our findings show that black hole seeds with characteristic mass of $\\rm 10^{5} M_{\\odot}$ are formed in the pr...

  18. Effect of pyrolyzed carbon black on asphalt cement. Part 2. Asphalt binder. Final report, September 1993-May 1995

    SciTech Connect (OSTI)

    Zeng, Y.; Lovell, C.W.

    1996-02-20T23:59:59.000Z

    Scrap tires derived from automobiles have become a large environmental problem in the United States. In the study, research is carried out to investigate the potential use of tire-derived pyrolyzed carbon black from scrap tires as an asphalt cement modifier. The asphlat cements used in the research were AC10 and AC20. Penetration and softening point tests were performed to obtain the consistency of the asphalt cements. The pyrolyzed carbon black, as provided by Wolf Industries, was combined with the asphalt cement in the following percentages: 5%, 10%, 15% and 20%. Penetration, softening point and ductility tests were performed to determine the temperature susceptibility of the modified binder as altered by the pyrolyzed carbon black. In order that the results are comparable to previous testing, commercial carbon black purchased from CABOT Industry was also used as a modifier in the tests. The same test procedures were applied to the asphalt cements modified by commercial carbon black. The test results contained in the report illustrate the viability of the pyrolyzed carbon black as an asphalt modifier. Recommendations are provided to facilitate further research on this particular project. A preliminary assessment of a test road using the pyrolyzed carbon is appended.

  19. The sensitivity of tropical convective precipitation to the direct radiative forcings of black carbon aerosols emitted from major regions

    E-Print Network [OSTI]

    Wang, Chien

    Previous works have suggested that the direct radiative forcing (DRF) of black carbon (BC) aerosols are able to force a significant change in tropical convective precipitation ranging from the Pacific and Indian Ocean to ...

  20. Effect of composite microstructure on electrical and mechanical properties of poly(vinyl acetate) composites with carbon black and clay.

    E-Print Network [OSTI]

    Miriyala, Sethu M.

    2009-05-15T23:59:59.000Z

    The electrical and mechanical behavior of carbon black filled poly(vinyl acetate) latex-based and solution-based polymer composites was examined. A set of experiments were performed to distinguish composites with a segregated network (emulsion...

  1. From Supermassive Black Holes to Dwarf Elliptical Nuclei: a Mass Continuum

    E-Print Network [OSTI]

    Elizabeth Wehner; William Harris

    2006-04-03T23:59:59.000Z

    Considerable evidence suggests that supermassive black holes reside at the centers of massive galactic bulges. At a lower galactic mass range, many dwarf galaxies contain extremely compact nuclei that structurally resemble massive globular clusters. We show that both these types of central massive objects (CMO's) define a single unbroken relation between CMO mass and the luminosity of their host galaxy spheroid. Equivalently, M_CMO is directly proportional to the host spheroid mass over 4 orders of magnitude. We note that this result has been simultaneously and independently identified by Cote et al. (2006), see also Ferrarese et al. (2006). We therefore suggest that the dE,N nuclei may be the low-mass analogs of supermassive black holes, and that these two types of CMO's may have both developed starting from similar initial formation processes. The overlap mass interval between the two types of CMO's is small, and suggests that for M_CMO > 10^7 M_sun, the formation of a black hole was strongly favored, perhaps because the initial gas infall to the center was too rapid and violent for star formation to occur efficiently.

  2. Center-of-mass energy for the Plebanski-Demianski black hole

    SciTech Connect (OSTI)

    Sharif, M., E-mail: msharif.math@pu.edu.pk; Haider, Nida, E-mail: nida.haider12@gmail.com [University of the Punjab, Department of Mathematics (Pakistan)] [University of the Punjab, Department of Mathematics (Pakistan)

    2013-07-15T23:59:59.000Z

    We study the center-of-mass energy of the particles colliding in the vicinity of acceleration and event horizons of the Plebanski and Demianski class of black holes. We calculate the collision energy of uncharged particles in the center-of-mass frame that are freely falling along the equatorial plane of a charged accelerating and rotating black hole with an NUT parameter. This energy turns out to be infinite in the non-extremal case, while in the extremal case, it becomes infinitely large near the event horizon only if the particle has the critical angular momentum. We conclude that the center-of-mass energy depends on the rotation and the NUT parameter.

  3. Modeling soil respiration based on carbon, nitrogen, and root mass across diverse Great Lake forests

    E-Print Network [OSTI]

    Chen, Jiquan

    . Introduction Linkages between atmospheric carbon dioxide and global thermal properties have forcedModeling soil respiration based on carbon, nitrogen, and root mass across diverse Great Lake the examination of biospheric carbon flows and pools. Variability in carbon storage or the net ecosystem exchange

  4. Renormalized spin coefficients in the accumulated orbital phase for unequal mass black hole binaries

    E-Print Network [OSTI]

    László Á. Gergely; Peter L. Biermann; Balázs Mikóczi; Zoltán Keresztes

    2009-09-03T23:59:59.000Z

    We analyze galactic black hole mergers and their emitted gravitational waves. Such mergers have typically unequal masses with mass ratio of the order 1/10. The emitted gravitational waves carry the inprint of spins and mass quadrupoles of the binary components. Among these contributions, we consider here the quasi-precessional evolution of the spins. A method of taking into account these third post-Newtonian (3PN) effects by renormalizing (redefining) the 1.5 PN and 2PN accurate spin contributions to the accumulated orbital phase is developed.

  5. A Correlation between Galaxy Light Concentration and Supermassive Black Hole Mass

    E-Print Network [OSTI]

    Alister W. Graham; Peter Erwin; Nicola Caon; Ignacio Trujillo

    2001-11-09T23:59:59.000Z

    We present evidence for a strong correlation between the concentration of bulges and the mass of their central supermassive black hole (M_bh) -- more concentrated bulges have more massive black holes. Using C_{r_e}(1/3) from Trujillo, Graham & Caon (2001b) as a measure of bulge concentration, we find that log (M_bh/M_sun) = 6.81(+/-0.95)C_{r_e}(1/3) + 5.03(+/-0.41). This correlation is shown to be marginally stronger (Spearman's r_s=0.91) than the relationship between the logarithm of the stellar velocity dispersion and log M_bh (Spearman's r_s=0.86), and has comparable, or less, scatter (0.31 dex in log M_bh), which decreases to 0.19 dex when we use only those galaxies whose supermassive black hole's radius of influence is resolved and remove one well understood outlying data point).

  6. Gasification behavior of carbon residue in bed solids of black liquor gasifier

    SciTech Connect (OSTI)

    Preto, Fernando; Zhang, Xiaojie (Frank); Wang, Jinsheng [CANMET Energy Technology Centre, Natural Resources (Canada)

    2008-07-15T23:59:59.000Z

    Steam gasification of carbon residue in bed solids of a low-temperature black liquor gasifier was studied using a thermogravimetric system at 3 bar. Complete gasification of the carbon residue, which remained unreactive at 600 C, was achieved in about 10 min as the temperature increased to 800 C. The rate of gasification and its temperature dependence were evaluated from the non-isothermal experiment results. Effects of particle size and adding H{sub 2} and CO to the gasification agent were also studied. The rate of steam gasification could be taken as zero order in carbon until 80% of carbon was gasified, and for the rest of the gasification process the rate appeared to be first order in carbon. The maximum rate of carbon conversion was around 0.003/s and the activation energy was estimated to be in the range of 230-300 kJ/mol. The particle size did not show significant effect on the rate of gasification. Hydrogen and carbon monoxide appeared to retard the onset of the gasification process. (author)

  7. Small mass plunging into a Kerr black hole: Anatomy of the inspiral-merger-ringdown waveforms

    E-Print Network [OSTI]

    Andrea Taracchini; Alessandra Buonanno; Gaurav Khanna; Scott A. Hughes

    2014-04-07T23:59:59.000Z

    We numerically solve the Teukolsky equation in the time domain to obtain the gravitational-wave emission of a small mass inspiraling and plunging into the equatorial plane of a Kerr black hole. We account for the dissipation of orbital energy using the Teukolsky frequency-domain gravitational-wave fluxes for circular, equatorial orbits, down to the light-ring. We consider Kerr spins $-0.99 \\leq q \\leq 0.99$, and compute the inspiral-merger-ringdown (2,2), (2,1), (3,3), (3,2), (4,4), and (5,5) modes. We study the large-spin regime, and find a great simplicity in the merger waveforms, thanks to the extremely circular character of the plunging orbits. We also quantitatively examine the mixing of quasinormal modes during the ringdown, which induces complicated amplitude and frequency modulations in the waveforms. Finally, we explain how the study of small mass-ratio black-hole binaries helps extending effective-one-body models for comparable-mass, spinning black-hole binaries to any mass ratio and spin magnitude.

  8. The Mass of the Black Hole in the Seyfert 1 Galaxy NGC 4593 from Reverberation Mapping

    E-Print Network [OSTI]

    Kelly D. Denney; Misty C. Bentz; Bradley M. Peterson; Richard W. Pogge; Edward M. Cackett; Matthias Dietrich; Jeffrey K. J. Fogel; Himel Ghosh; Keith Horne; Charles Kuehn; Takeo Minezaki; Christopher A. Onken; Vladimir I. Pronik; Douglas O. Richstone; Sergey G. Sergeev; Marianne Vestergaard; Matthew G. Walker; Yuzuru Yoshii

    2006-08-18T23:59:59.000Z

    We present new observations leading to an improved black hole mass estimate for the Seyfert 1 galaxy NGC 4593 as part of a reverberation-mapping campaign conducted at the MDM Observatory. Cross-correlation analysis of the H_beta emission-line light curve with the optical continuum light curve reveals an emission-line time delay of 3.73 (+-0.75) days. By combining this time delay with the H_beta line width, we derive a central black hole mass of M_BH = 9.8(+-2.1)x10^6 M_sun, an improvement in precision of a factor of several over past results.

  9. The Mass of the Black Hole in the Seyfert 1 Galaxy NGC 4593 from Reverberation Mapping

    E-Print Network [OSTI]

    Denney, K D; Peterson, B M; Pogge, R W; Cackett, E M; Dietrich, M; Fogel, J K J; Ghosh, H; Horne, K; Kuehn, C; Minezaki, T; Onken, C A; Pronik, V I; Richstone, D O; Sergeev, S G; Vestergaard, M; Walker, M G; Yoshii, Y; Denney, Kelly D.; Bentz, Misty C.; Peterson, Bradley M.; Pogge, Richard W.; Cackett, Edward M.; Dietrich, Matthias; Fogel, Jeffrey K. J.; Ghosh, Himel; Horne, Keith; Kuehn, Charles; Minezaki, Takeo; Onken, Christopher A.; Pronik, Vladimir I.; Richstone, Douglas O.; Sergeev, Sergey G.; Vestergaard, Marianne; Walker, Matthew G.; Yoshii, Yuzuru

    2006-01-01T23:59:59.000Z

    We present new observations leading to an improved black hole mass estimate for the Seyfert 1 galaxy NGC 4593 as part of a reverberation-mapping campaign conducted at the MDM Observatory. Cross-correlation analysis of the H_beta emission-line light curve with the optical continuum light curve reveals an emission-line time delay of 3.73 (+-0.75) days. By combining this time delay with the H_beta line width, we derive a central black hole mass of M_BH = 9.8(+-2.1)x10^6 M_sun, an improvement in precision of a factor of several over past results.

  10. Constraining the Lifetime of QSOs with Present-day Mass Function of Supermassive Black Holes

    E-Print Network [OSTI]

    T. Hosokawa

    2002-05-13T23:59:59.000Z

    Using the theoretical models of the QSO formation, we can reproduce optical QSO luminosity functions (LFs) at high redshifts (z > 2.2). Two different models can reproduce LFs successfully, though the lifetime of QSOs, t_Q, and the relation between the black hole mass and the host halo mass are different each other; t_Q = 10^6yr, in one model, t_Q > 10^7yr, in other models. Here, we propose a method to break this degeneracy. We calculate the mass function of supermassive black holes (SMBHs) at z=2.5, and compare the result with the current mass function obtained by Salucci et al.(1999). In the shorter lifetime model, the mass function at z=2.5 exceeds that of z=0.0 by one order of magnitude, then it should be ruled out. We conclude that the lifetime is at least t_Q > 10^7yr. Next, we examine the difference of the formation epoch of SMBHs existing at z=3.0 for each model under the model assumptions. We simply discuss the difference of formation epoch as another possible model-discriminator.

  11. Search for gravitational wave ringdowns from perturbed intermediate mass black holes in LIGO-Virgo data from 2005–2010

    E-Print Network [OSTI]

    Aggarwal, Nancy

    We report results from a search for gravitational waves produced by perturbed intermediate mass black holes (IMBH) in data collected by LIGO and Virgo between 2005 and 2010. The search was sensitive to astrophysical sources ...

  12. Myers-Perry black holes with scalar hair and a mass gap

    E-Print Network [OSTI]

    Yves Brihaye; Carlos Herdeiro; Eugen Radu

    2014-08-24T23:59:59.000Z

    We construct a family of asymptotically flat, rotating black holes with scalar hair and a regular horizon, within five dimensional Einstein's gravity minimally coupled to a complex, massive scalar field doublet. These solutions are supported by rotation and have no static limit. They are described by their mass $M$, two equal angular momenta $J_1=J_2\\equiv J$ and a conserved Noether charge $Q$, measuring the scalar hair. For vanishing horizon size the solutions reduce to five dimensional boson stars. In the limit of vanishing Noether charge density, the scalar field becomes point-wise arbitrarily small and the geometry becomes, locally, arbitrarily close to that of a specific set of Myers-Perry black holes (MPBHs); but there remains a global difference with respect to the latter, manifest in a finite mass gap. Thus, the scalar hair never becomes a linear perturbation of MPBHs. This is a qualitative difference when compared to Kerr black holes with scalar hair~\\cite{Herdeiro:2014goa}. Whereas the existence of the latter can be anticipated in linear theory, from the existence of scalar bound states on the Kerr geometry (i.e. scalar clouds), the hair of these MPBHs is intrinsically non-linear.

  13. Eight powers of ten: similarities in black hole accretion on all mass scales

    E-Print Network [OSTI]

    Rob Fender; Elmar Koerding; Tomaso Belloni; Phil Uttley; Ian McHardy; Tasso Tzioumis

    2007-06-26T23:59:59.000Z

    In this paper we discuss the recent advances in the quantitative comparison of accretion, and the accretion:jet coupling, in accreting black holes in both X-ray binaries (where M ~ 10Msun) and Active Galactic Nuclei (10^5Msun < M < 10^9Msun). These similarities include the radiative efficiency and jet power as a function of accretion rate, which are themselves probably the origin of the `fundamental plane of black hole activity'. A second `fundamental plane' which connects mass, accretion rate and timing properties provides us with a further physical diagnostic. Patterns of radio loudness (i.e. jet production) as a function of luminosity and accretion state are shown to be similar for X-ray binaries and AGN. Finally we discuss how neutron stars are a useful control sample, and what the future may hold for this field.

  14. The ecology of star clusters and intermediate mass black holes in the Galactic bulge

    E-Print Network [OSTI]

    Simon Portegies Zwart; Holger Baumgardt; Stephen L. W. McMillan; Junichiro Makino; Piet Hut; Toshi Ebisuzaki

    2005-12-05T23:59:59.000Z

    We simulate the inner 100pc of the Milky-Way Galaxy to study the formation and evolution of the population of star clusters and intermediate mass black holes. For this study we perform extensive direct N-body simulations of the star clusters which reside in the bulge, and of the inner few tenth of parsecs of the super massive black hole in the Galactic center. In our N-body simulations the dynamical friction of the star cluster in the tidal field of the bulge are taken into account via (semi)analytic soluations. The N-body calculations are used to calibrate a (semi)analytic model of the formation and evolution of the bulge. We find that about 10% of the clusters born within 100pc of the Galactic center undergo core collapse during their inward migration and form intermediate-mass black holes (IMBHs) via runaway stellar merging. After the clusters dissolve, these IMBHs continue their inward drift, carrying a few of the most massive stars with them. We predict that region within about 10 parsec of the SMBH is populated by about 50IMBHs of some 1000Msun. Several of these are expected to be accompanied still by some of the most massive stars from the star cluster. We also find that within a few milliparsec of the SMBH there is a steady population of several IMBHs. This population drives the merger rate between IMBHs and the SMBH at a rate of about one per 10Myr, sufficient to build the accumulate majority of mass of the SMBH. Mergers of IMBHs with SMBHs throughout the universe are detectable by LISA, at a rate of about two per week.

  15. 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

    2006-03-08T23:59:59.000Z

    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.

  16. Historical and future black carbon deposition on the three ice caps: Ice core measurements and model simulations from 1850 to 2100

    E-Print Network [OSTI]

    Historical and future black carbon deposition on the three ice caps: Ice core measurements black carbon deposition on the three ice caps: Ice core measurements and model simulations from 1850 tends to enhance snow and ice melting due to the absorption caused by the increased BC deposition

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

    E-Print Network [OSTI]

    Clovis Hopman; Tal Alexander

    2006-03-13T23:59:59.000Z

    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.

  18. Dynamic molecular structure of plant biomass-derived black carbon (biochar)

    SciTech Connect (OSTI)

    Keiluweit, M.; Nico, P.S.; Johnson, M.G.; Kleber, M.

    2009-11-15T23:59:59.000Z

    Char black carbon (BC), the solid residue of incomplete combustion, is continuously being added to soils and sediments due to natural vegetation fires, anthropogenic pollution, and new strategies for carbon sequestration ('biochar'). Here we present a molecular-level assessment of the physical organization and chemical complexity of biomass-derived chars and, specifically, that of aromatic carbon in char structures. BET-N{sub 2} surface area, X-ray diffraction (XRD), synchrotron-based Near-edge X-ray Absorption Fine Structure (NEXAFS), and Fourier transform infrared (FT-IR) spectroscopy are used to show how two plant materials (wood and grass) undergo analogous, but quantitatively different physical-chemical transitions as charring temperature increases from 100 to 700 C. These changes suggest the existence of four distinct categories of char consisting of a unique mixture of chemical phases and physical states: (i) in transition chars the crystalline character of the precursor materials is preserved, (ii) in amorphous chars the heat-altered molecules and incipient aromatic polycondensates are randomly mixed, (iii) composite chars consist of poorly ordered graphene stacks embedded in amorphous phases, and (iv) turbostratic chars are dominated by disordered graphitic crystallites. The molecular variations among the different char categories translate into differences in their ability to persist in the environment and function as environmental sorbents.

  19. A ~50,000 solar mass black hole in the nucleus of RGG 118

    E-Print Network [OSTI]

    Baldassare, Vivienne; Gallo, Elena; Greene, Jenny

    2015-01-01T23:59:59.000Z

    Scaling relations between black hole (BH) masses and their host galaxy properties have been studied extensively over the last two decades, and point towards co-evolution of central massive BHs and their hosts. However, these relations remain poorly constrained for BH masses below $\\sim10^{6}$ M_sun. Here we present optical and X-ray observations of the dwarf galaxy RGG 118 taken with the Magellan Echellette Spectrograph on the 6.5m Clay Telescope and Chandra X-ray Observatory. Based on Sloan Digital Sky Survey spectroscopy, RGG 118 was identified as possessing narrow emission line ratios indicative of photoionization partly due to an active galactic nucleus. Our higher resolution spectroscopy clearly reveals broad H$\\alpha$ emission in the spectrum of RGG 118. Using virial BH mass estimate techniques, we calculate a BH mass of $\\sim50,000$ \\msun. We detect a nuclear X-ray point source in RGG 118, suggesting a total accretion powered luminosity of $L=4\\times10^{40}~{\\rm erg~s^{-1}}$, and an Eddington fraction ...

  20. Spectroscopy of the near-nuclear regions of Cygnus A: estimating the mass of the supermassive black hole

    E-Print Network [OSTI]

    C. Tadhunter; A. Marconi; D. Axon; K. Wills; T. G. Robinson; N. Jackson

    2003-02-25T23:59:59.000Z

    We use a combination of high spatial resolution optical and near-IR spectroscopic data to make a detailed study of the kinematics of the NLR gas in the near-nuclear regions of the powerful, FRII radio galaxy Cygnus A (z=0.0560), with the overall goal of placing limits on the mass of any supermassive black hole in the core. Our K-band infrared observations (0.75 arcsec seeing) -- taken with NIRSPEC on the Keck II telescope -- show a smooth rotation pattern across the nucleus in the Paschen alpha and H_2 emission lines along a slit position (PA180) close to perpendicular to the radio axis, however, there is no evidence for such rotation along the radio axis (PA105). Higher spatial resolution observations of the [OIII]5007 emission line -- taken with STIS on the Hubble Space Telescope (HST) -- confirm the general rotation pattern of the gas in the direction perpendicular to the radio axis, and provide evidence for steep velocity gradients within a radius of 0.1 arcsec of the core. The circular velocities measured from both the Keck and HST data lead to an estimate of the mass of the supermassive black hole of 2.5+/-0.7x10^9 solar masses. For the host galaxy properties of Cygnus A, this mass is consistent with the global correlations between black hole mass and host galaxy properties deduced for non-active galaxies. Therefore, despite the extreme power of its radio source and the quasar-like luminosity of its AGN, the black hole in Cygnus A is not unusually massive considering theluminosity of its host galaxy. Indeed, the estimated mass of the black hole in Cygnus A is similar to that inferred for the supermassive black hole in the FRI radio galaxy M87, despite the fact that the AGN and radio jets of Cygnus A are 2 -- 3 orders of magnitude more powerful.

  1. New concepts in energy and mass transport within carbon nanotubes

    E-Print Network [OSTI]

    Choi, Wonjoon, Ph. D. Massachusetts Institute of Technology

    2012-01-01T23:59:59.000Z

    The unique structure of carbon nanotubes (CNTs) contributes to their distinguished properties, making them useful in nanotechnology. CNTs have been explored for energy transport in next-generation, such as light-emitting ...

  2. Systematic Uncertainties in Black Hole Masses Determined from Single Epoch Spectra

    E-Print Network [OSTI]

    Denney, Kelly D; Dietrich, Matthias; Vestergaard, Marianne; Bentz, Misty C

    2008-01-01T23:59:59.000Z

    We explore the nature of systematic errors that can arise in measurement of black hole masses from single-epoch spectra of active galactic nuclei (AGNs) by utilizing the many epochs available for NGC 5548 and PG1229+204 from reverberation mapping databases. In particular, we examine systematics due to AGN variability, contamination due to constant spectral components (i.e., narrow lines and host galaxy flux), data quality (i.e., signal-to-noise ratio, S/N), and blending of spectral features by comparing the precision and accuracy of single-epoch mass measurements to those of recent reverberation mapping studies. We calculate masses by characterizing the broad Hbeta emission line by both the full width at half maximum and the line dispersion and demonstrate the importance of removing narrow emission-line components and host starlight. We find that the reliability of line width measurements rapidly decreases for S/N lower than ~10 to 20 (per pixel) and that fitting the line profiles instead of direct measuremen...

  3. Prospects for detecting Dark Matter with neutrino telescopes in Intermediate Mass Black Holes scenarios

    E-Print Network [OSTI]

    Bertone, Gianfranco

    2006-01-01T23:59:59.000Z

    Current strategies of indirect Dark Matter detection with neutrino telescopes are based on the search for high-energy neutrinos from the Solar core or from the center of the Earth. Here, we propose a new strategy based on the detection of neutrinos from Dark Matter annihilations in 'mini-spikes' around Intermediate Mass Black Holes. Neutrino fluxes, in this case, depend on the annihilation cross-section of Dark Matter particles, whereas solar and terrestrial fluxes are sensitive to the scattering cross-section off nucleons, a circumstance that makes the proposed search complementary to the existing ones. We discuss the prospects for detection with upcoming under-water and under-ice experiments such as ANTARES and IceCube, and show that several, up to many, sources could be detected with both experiments. A kilometer scale telescope in the Mediterranean appears to be ideally suited for the proposed search.

  4. Prospects for detecting Dark Matter with neutrino telescopes in Intermediate Mass Black Holes scenarios

    E-Print Network [OSTI]

    Gianfranco Bertone

    2006-05-26T23:59:59.000Z

    Current strategies of indirect Dark Matter detection with neutrino telescopes are based on the search for high-energy neutrinos from the Solar core or from the center of the Earth. Here, we propose a new strategy based on the detection of neutrinos from Dark Matter annihilations in 'mini-spikes' around Intermediate Mass Black Holes. Neutrino fluxes, in this case, depend on the annihilation cross-section of Dark Matter particles, whereas solar and terrestrial fluxes are sensitive to the scattering cross-section off nucleons, a circumstance that makes the proposed search complementary to the existing ones. We discuss the prospects for detection with upcoming under-water and under-ice experiments such as ANTARES and IceCube, and show that several, up to many, sources could be detected with both experiments. A kilometer scale telescope in the Mediterranean appears to be ideally suited for the proposed search.

  5. AMUSE-Virgo I. Super-massive black holes in low-mass spheroids

    E-Print Network [OSTI]

    Elena Gallo; Tommaso Treu; Jeremy Jacob; Jong-Hak Woo; Phil Marshall; Robert Antonucci

    2008-03-04T23:59:59.000Z

    We present the first results from the AGN Multiwavelength Survey of Early-type galaxies in the Virgo cluster (AMUSE-Virgo). This large program targets 100 early-type galaxies with the Advanced CCD Imaging Spectrometer on board the Chandra X-ray Observatory and the Multi-band Imaging Photometer on board the Spitzer Space Telescope, with the aim of providing an unbiased census of low-level super-massive black hole (SMBH) activity in the local universe. Here we report on the Chandra observations of the first 16 targets, and combine them with results from archival data of another, typically more massive, 16 targets. Point-like X-ray emission from a position coincident with the optical nucleus is detected in 50% of the galaxies (down to our completeness limit of ~4E+38 erg/sec). Two of the X-ray nuclei are hosted by galaxies (VCC1178=N4464 and VCC1297=N4486B) with absolute B magnitudes fainter than -18, where nuclear star clusters are known to become increasingly common. After carefully accounting for possible contamination from low mass X-ray binaries, we argue that the detected nuclear X-ray sources are most likely powered by low-level accretion on to a SMBH, with a <11% chance contamination in VCC1178, where a star cluster is barely resolvable in archival Hubble Space Telescope images. Based on black hole mass estimates from the global properties of the host galaxies, all the detected nuclei are highly sub-Eddington, with luminosities in the range -8.4mass M_star of the host galaxy: only between 3-44% of the galaxies with M_star<1E+10 M_Sun harbor an X-ray active SMBH. The fraction rises to between 49-87% in galaxies with stellar mass above 1E+10 M_Sun (at the 95% confidence level).

  6. Systematic Uncertainties in Black Hole Masses Determined from Single Epoch Spectra

    E-Print Network [OSTI]

    Kelly D. Denney; Bradley M. Peterson; Matthias Dietrich; Marianne Vestergaard; Misty C. Bentz

    2008-10-20T23:59:59.000Z

    We explore the nature of systematic errors that can arise in measurement of black hole masses from single-epoch spectra of active galactic nuclei (AGNs) by utilizing the many epochs available for NGC 5548 and PG1229+204 from reverberation mapping databases. In particular, we examine systematics due to AGN variability, contamination due to constant spectral components (i.e., narrow lines and host galaxy flux), data quality (i.e., signal-to-noise ratio, S/N), and blending of spectral features by comparing the precision and accuracy of single-epoch mass measurements to those of recent reverberation mapping studies. We calculate masses by characterizing the broad Hbeta emission line by both the full width at half maximum and the line dispersion and demonstrate the importance of removing narrow emission-line components and host starlight. We find that the reliability of line width measurements rapidly decreases for S/N lower than ~10 to 20 (per pixel) and that fitting the line profiles instead of direct measurement of the data does not mitigate this problem but can, in fact, introduce systematic errors. We also conclude that a full spectral decomposition to deblend the AGN and galaxy spectral features is unnecessary except to judge the contribution of the host galaxy to the luminosity and to deblend any emission lines that may inhibit accurate line width measurements. Finally, we present an error budget which summarizes the minimum observable uncertainties as well as the amount of additional scatter and/or systematic offset that can be expected from the individual sources of error investigated. In particular, we find that the minimum observable uncertainty in single-epoch mass estimates due to variability is ~ 20 per pixel) spectra.

  7. On The Linearity of The Black Hole - Bulge Mass Relation in Active and in Nearby Galaxies

    E-Print Network [OSTI]

    Ari Laor

    2001-01-23T23:59:59.000Z

    Analysis of PG quasar observations suggests a nonlinear relation between the black hole mass, M_BH, and the bulge mass, M_bulge, although a linear relation, as proposed for nearby galaxies, cannot be ruled out. New M_BH values for nearby galaxies from Gebhardt et al., and L_bulge measurements for Seyfert 1 galaxies from Virani et al., are used here to obtain a more accurate value for the slope of the M_BH-M_bulge relation. The combined sample of 40 active and non-active galaxies suggests a significantly nonlinear relation, M_BH\\propto M_bulge^{1.53\\pm 0.14}. Further support for a nonlinear relation is provided by the slope of the M_BH-stellar velocity dispersion relation found recently, and by the low M_BH found in late type spiral galaxies. The mean M_BH/M_bulge ratio is therefore not a universal constant, but rather drops from ~0.5% in bright (M_V ~ -22) ellipticals, to ~0.05% in low luminosity (M_V ~ -18) bulges. Hubble Space Telescope determinations of M_BH in late type spirals, and of the bulge magnitude in narrow line Seyfert 1 galaxies (both predicted to have low M_BH), can further test the validity of the nonlinear M_BH-M_bulge relation.

  8. Nano-Structural Elucidation in Carbon Black Loaded NR Vulcanizate by 3D-TEM and In Situ WAXD Measurements

    SciTech Connect (OSTI)

    Ikeda,Y.; Kato, A.; Shimanuki, J.; Kohjiya, S.; Tosaka, M.; Poompradub, S.; Toki, S.; Hsiao, B.

    2007-01-01T23:59:59.000Z

    Three dimensional (3D) visualization of nanometer structure of carbon black dispersion in rubbery matrix has successfully been studied and reported in this paper. Use of 3D-TEM, which is computerized tomography combined with transmission electron microscopy (TEM), enabled us to reconstruct 3D images of carbon black aggregates in natural rubber (NR) matrix. The TEM measurements were conducted by a bright-field method on thin samples without any electron staining. The sample was subject to uni-axial tilting (+65 degree to -65 degree with 2 degree increment) in the sample chamber, and 66 TEM images were taken on each sample. These TEM images were used for computerized tomography to reconstruct the 3D image. This technique is designated as 3D-TEM. The nano-structural features observed by 3D-TEM were in conformity with the electron-conductivity results, and the percolation behavior was recognized. These results were further supplemented by in situ wide-angle X-ray diffraction (WAXD), i.e., simultaneous WAXD and tensile measurements on the sample to observe the strain-induced crystallization in NR vulcanizate. Upon tensile elongation, the crystallization was clearly observed in WAXD in the presence of carbon black, and it contributed to the tensile properties. In order to understand the performances of filled NR vulcanizates, it surely is necessary to know the structural states of the mixed nano-filler and the crystallites produced upon elongation.

  9. The lowest-mass stellar black holes: catastrophic death of neutron stars in gamma-ray bursts

    E-Print Network [OSTI]

    K. Belczynski; R. O'Shaughnessy; V. Kalogera; F. Rasio; R. Taam; T. Bulik

    2008-04-16T23:59:59.000Z

    Mergers of double neutron stars are considered the most likely progenitors for short gamma-ray bursts. Indeed such a merger can produce a black hole with a transient accreting torus of nuclear matter (Lee & Ramirez-Ruiz 2007, Oechslin & Janka 2006), and the conversion of a fraction of the torus mass-energy to radiation can power a gamma-ray burst (Nakar 2006). Using available binary pulsar observations supported by our extensive evolutionary calculations of double neutron star formation, we demonstrate that the fraction of mergers that can form a black hole -- torus system depends very sensitively on the (largely unknown) maximum neutron star mass. We show that the available observations and models put a very stringent constraint on this maximum mass under the assumption that a black hole formation is required to produce a short gamma-ray burst in a double neutron star merger. Specifically, we find that the maximum neutron star mass must be within 2 - 2.5 Msun. Moreover, a single unambiguous measurement of a neutron star mass above 2.5 Msun would exclude a black hole -- torus central engine model of short gamma-ray bursts in double neutron star mergers. Such an observation would also indicate that if in fact short gamma-ray bursts are connected to neutron star mergers, the gamma-ray burst engine is best explained by the lesser known model invoking a highly magnetized massive neutron star (e.g., Usov 1992; Kluzniak & Ruderman 1998; Dai et al. 2006; Metzger, Quataert & Thompson 2007).

  10. AMUSE-Virgo I. Super-massive black holes in low-mass spheroids

    E-Print Network [OSTI]

    Gallo, Elena; Jacob, Jeremy; Woo, Jong-Hak; Marshall, Phil; Antonucci, Robert

    2007-01-01T23:59:59.000Z

    (Abridged) We present the first results from the AGN Multiwavelength Survey of Early-type galaxies in the Virgo cluster (AMUSE-Virgo). This large program targets 100 early-type galaxies with the Chandra X-ray Observatory and the Spitzer Space Telescope, with the aim of providing an unbiased census of low-level super-massive black hole (SMBH) activity in the local universe. Here we report on the Chandra observations of the first 16 targets, and combine them with results from archival data of another, typically more massive, 16 targets. Point-like X-ray emission from a position coincident with the optical nucleus is detected in 50% of the galaxies. Two of the X-ray nuclei are hosted by galaxies (VCC1178=N4464 and VCC1297=N4486B) with absolute B magnitudes fainter than -18, where nuclear star clusters are known to become increasingly common. After carefully accounting for possible contamination from low mass X-ray binaries, we argue that the detected nuclear X-ray sources are most likely powered by low-level acc...

  11. EVIDENCE FOR A STELLAR DISRUPTION BY AN INTERMEDIATE-MASS BLACK HOLE IN AN EXTRAGALACTIC GLOBULAR CLUSTER

    SciTech Connect (OSTI)

    Irwin, Jimmy A. [Department of Physics and Astronomy, University of Alabama, Box 870324, Tuscaloosa, AL 35487 (United States); Brink, Thomas G.; Bregman, Joel N. [Department of Astronomy, University of Michigan, 500 Church Street, Ann Arbor, MI 48109-1042 (United States); Roberts, Timothy P. [Department of Physics, Durham University, South Road, Durham DH1 3LE (United Kingdom)], E-mail: jairwin@ua.edu

    2010-03-20T23:59:59.000Z

    We report [O III] {lambda}5007 and [N II] {lambda}6583 emission from a globular cluster harboring the ultraluminous X-ray source CXOJ033831.8 - 352604 in the Fornax elliptical galaxy NGC 1399. No accompanying Balmer emission lines are present in the spectrum. One possibility is that the forbidden lines emanate from X-ray-illuminated debris of a star that has been tidally disrupted by an intermediate-mass black hole, with this debris also feeding the black hole leading to the observed X-ray emission. The line strengths indicate that the minimum size of the emitting region is {approx}10{sup 15} cm, and if the 70 km s{sup -1} half-widths of the emission lines represent rotation around the black hole, a minimum black hole mass of 1000 M {sub sun} is implied. The non-detection of H{alpha} and H{beta} emission lines suggests a white dwarf star was disrupted, although the presence of strong nitrogen emission is somewhat of a mystery.

  12. Mass production of multi-wall carbon nanotubes by metal dusting process with high yield

    SciTech Connect (OSTI)

    Ghorbani, H. [School of Metallurgy and Materials Engineering, Iran University of Science and Technology, Narmak, Tehran (Iran, Islamic Republic of)] [School of Metallurgy and Materials Engineering, Iran University of Science and Technology, Narmak, Tehran (Iran, Islamic Republic of); Rashidi, A.M., E-mail: Rashidiam@ripi.ir [Nanotechnology Research Center, Research Institute of Petroleum Industry (RIPI), West Blvd. Azadi Sport Complex, P.O. Box 14665-1998, Tehran (Iran, Islamic Republic of); Rastegari, S.; Mirdamadi, S. [School of Metallurgy and Materials Engineering, Iran University of Science and Technology, Narmak, Tehran (Iran, Islamic Republic of)] [School of Metallurgy and Materials Engineering, Iran University of Science and Technology, Narmak, Tehran (Iran, Islamic Republic of); Alaei, M. [Nanotechnology Research Center, Research Institute of Petroleum Industry (RIPI), West Blvd. Azadi Sport Complex, P.O. Box 14665-1998, Tehran (Iran, Islamic Republic of)] [Nanotechnology Research Center, Research Institute of Petroleum Industry (RIPI), West Blvd. Azadi Sport Complex, P.O. Box 14665-1998, Tehran (Iran, Islamic Republic of)

    2011-05-15T23:59:59.000Z

    Research highlights: {yields} Synthesis of carbon nanotubes over Fe-Ni nanoparticles supported alloy 304L. {yields} Production of carbon nanotubes with high yield (700-1000%) and low cost catalyst. {yields} Optimum growth condition is CO/H{sub 2} = 1/1, 100 cm{sup 3}/min, at 620 {sup o}C under long term repetitive thermal cycling. {yields} Possibility of the mass production by metal dusting process with low cost. -- Abstract: Carbon nanotube materials were synthesized over Fe-Ni nanoparticles generated during disintegration of the surface of alloy 304L under metal dusting environment. The metal dusting condition was simulated and optimized through exposing stainless steel samples during long term repetitive thermal cycling in CO/H{sub 2} = 1/1, total gas flow rate 100 cm{sup 3}/min, at 620 {sup o}C for 300 h. After reaction, surface morphology of the samples and also carbonaceous deposition which had grown on sample surfaces were examined by stereoscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Results revealed that multi-wall carbon nanotubes could be formed over nanocatalyst generated on the alloy surface by exploiting metal dusting process. By optimization of reaction parameters the yields of carbon nanotube materials obtained were 700-1000%. Also it has been shown herein that the amount of carbon nanotube materials remarkably increases when the reaction time is extended up to 300 h, indicating a possibility of the mass production by this easy method.

  13. Center of Mass Energy of the Collision for two Neutral Particles in the Background of a Kerr-Newman-Taub-NUT Black Hole

    E-Print Network [OSTI]

    Ayesha Zakria; Mubasher Jamil

    2015-01-26T23:59:59.000Z

    In this paper, we investigate the center of mass energy of the collision for two neutral particles with different rest masses falling freely from rest at infinity in the background of a Kerr-Newman-Taub-NUT black hole. Further, we discuss the center of mass energy near the horizon(s) of an extremal and non-extremal Kerr-Newman-Taub-NUT black hole and show that an arbitrarily high center of mass energy is achievable under some restrictions. We will study the special case of the center of mass energy when the specific energy, specific angular momentum and Carter constant of both the particles are same.

  14. ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

    SciTech Connect (OSTI)

    Brandon C. Nuttall

    2004-01-01T23:59:59.000Z

    CO{sub 2} emissions from the combustion of fossil fuels have been linked to global climate change. Proposed carbon management technologies include geologic sequestration of CO{sub 2}. A possible, but untested, sequestration strategy is to inject CO{sub 2} into organic-rich shales. Devonian black shales underlie approximately two-thirds of Kentucky and are thicker and deeper in the Illinois and Appalachian Basin portions of Kentucky than in central Kentucky. The Devonian black shales serve as both the source and trap for large quantities of natural gas; total gas in place for the shales in Kentucky is estimated to be between 63 and 112 trillion cubic feet. Most of this natural gas is adsorbed on clay and kerogen surfaces, analogous to methane storage in coal beds. In coals, it has been demonstrated that CO{sub 2} is preferentially adsorbed, displacing methane. Black shales may similarly desorb methane in the presence of CO{sub 2}. The concept that black, organic-rich Devonian shales could serve as a significant geologic sink for CO{sub 2} is the subject of current research. To accomplish this investigation, drill cuttings and cores were selected from the Kentucky Geological Survey Well Sample and Core Library. Methane and carbon dioxide adsorption analyses are being performed to determine the gas-storage potential of the shale and to identify shale facies with the most sequestration potential. In addition, sidewall core samples are being acquired to investigate specific black-shale facies, their potential CO{sub 2} uptake, and the resulting displacement of methane. Advanced logging techniques (elemental capture spectroscopy) are being investigated for possible correlations between adsorption capacity and geophysical log measurements. For the Devonian shale, average total organic carbon is 3.71 (as received) and mean random vitrinite reflectance is 1.16. Measured adsorption isotherm data range from 37.5 to 2,077.6 standard cubic feet of CO{sub 2} per ton (scf/ton) of shale. At 500 psia, adsorption capacity of the Lower Huron Member of the shale is 72 scf/ton. Initial estimates indicate a sequestration capacity of 5.3 billion tons CO{sub 2} in the Lower Huron Member of the Ohio shale in parts of eastern Kentucky and as much as 28 billion tons total in the deeper and thicker portions of the Devonian shales in Kentucky. The black shales of Kentucky could be a viable geologic sink for CO{sub 2}, and their extensive occurrence in Paleozoic basins across North America would make them an attractive regional target for economic CO{sub 2} storage and enhanced natural gas production.

  15. ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

    SciTech Connect (OSTI)

    Brandon C. Nuttall

    2004-04-01T23:59:59.000Z

    CO{sub 2} emissions from the combustion of fossil fuels have been linked to global climate change. Proposed carbon management technologies include geologic sequestration of CO{sub 2}. A possible, but untested, sequestration strategy is to inject CO{sub 2} into organic-rich shales. Devonian black shales underlie approximately two-thirds of Kentucky and are thicker and deeper in the Illinois and Appalachian Basin portions of Kentucky than in central Kentucky. The Devonian black shales serve as both the source and trap for large quantities of natural gas; total gas in place for the shales in Kentucky is estimated to be between 63 and 112 trillion cubic feet. Most of this natural gas is adsorbed on clay and kerogen surfaces, analogous to methane storage in coal beds. In coals, it has been demonstrated that CO{sub 2} is preferentially adsorbed, displacing methane. Black shales may similarly desorb methane in the presence of CO{sub 2}. The concept that black, organic-rich Devonian shales could serve as a significant geologic sink for CO{sub 2} is the subject of current research. To accomplish this investigation, drill cuttings and cores were selected from the Kentucky Geological Survey Well Sample and Core Library. Methane and carbon dioxide adsorption analyses are being performed to determine the gas-storage potential of the shale and to identify shale facies with the most sequestration potential. In addition, sidewall core samples are being acquired to investigate specific black-shale facies, their potential CO{sub 2} uptake, and the resulting displacement of methane. Advanced logging techniques (elemental capture spectroscopy) are being investigated for possible correlations between adsorption capacity and geophysical log measurements. For the Devonian shale, average total organic carbon is 3.71 percent (as received) and mean random vitrinite reflectance is 1.16. Measured adsorption isotherm data range from 37.5 to 2,077.6 standard cubic feet of CO{sub 2} per ton (scf/ton) of shale. At 500 psia, adsorption capacity of the Lower Huron Member of the shale is 72 scf/ton. Initial estimates indicate a sequestration capacity of 5.3 billion tons CO{sub 2} in the Lower Huron Member of the Ohio shale in parts of eastern Kentucky and as much as 28 billion tons total in the deeper and thicker portions of the Devonian shales in Kentucky. The black shales of Kentucky could be a viable geologic sink for CO{sub 2}, and their extensive occurrence in Paleozoic basins across North America would make them an attractive regional target for economic CO{sub 2} storage and enhanced natural gas production.

  16. ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

    SciTech Connect (OSTI)

    Brandon C. Nuttall

    2003-10-29T23:59:59.000Z

    CO{sub 2} emissions from the combustion of fossil fuels have been linked to global climate change. Proposed carbon management technologies include geologic sequestration of CO{sub 2}. A possible, but untested, sequestration strategy is to inject CO{sub 2} into organic-rich shales. Devonian black shales underlie approximately two-thirds of Kentucky and are thicker and deeper in the Illinois and Appalachian Basin portions of Kentucky than in central Kentucky. The Devonian black shales serve as both the source and trap for large quantities of natural gas; total gas in place for the shales in Kentucky is estimated to be between 63 and 112 trillion cubic feet. Most of this natural gas is adsorbed on clay and kerogen surfaces, analogous to methane storage in coal beds. In coals, it has been demonstrated that CO{sub 2} is preferentially adsorbed, displacing methane. Black shales may similarly desorb methane in the presence of CO{sub 2}. The concept that black, organic-rich Devonian shales could serve as a significant geologic sink for CO{sub 2} is the subject of current research. To accomplish this investigation, drill cuttings and cores were selected from the Kentucky Geological Survey Well Sample and Core Library. Methane and carbon dioxide adsorption analyses are being performed to determine the gas-storage potential of the shale and to identify shale facies with the most sequestration potential. In addition, sidewall core samples are being acquired to investigate specific black-shale facies, their potential CO{sub 2} uptake, and the resulting displacement of methane. Advanced logging techniques (elemental capture spectroscopy) are being investigated for possible correlations between adsorption capacity and geophysical log measurements. For the Devonian shale, average total organic carbon is 3.71 (as received) and mean random vitrinite reflectance is 1.16. Measured adsorption isotherm data range from 37.5 to 2,077.6 standard cubic feet of CO{sub 2} per ton (scf/ton) of shale. At 500 psia, adsorption capacity of the Lower Huron Member of the shale is 72 scf/ton. Initial estimates indicate a sequestration capacity of 5.3 billion tons CO{sub 2} in the Lower Huron Member of the Ohio shale in parts of eastern Kentucky and as much as 28 billion tons total in the deeper and thicker portions of the Devonian shales in Kentucky. The black shales of Kentucky could be a viable geologic sink for CO{sub 2}, and their extensive occurrence in Paleozoic basins across North America would make them an attractive regional target for economic CO{sub 2} storage and enhanced natural gas production.

  17. ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

    SciTech Connect (OSTI)

    Brandon C. Nuttall

    2003-04-28T23:59:59.000Z

    Proposed carbon management technologies include geologic sequestration of CO{sub 2}. A possible, but untested, strategy is to inject CO{sub 2} into organic-rich shales of Devonian age. Devonian black shales underlie approximately two-thirds of Kentucky and are generally thicker and deeper in the Illinois and Appalachian Basin portions of Kentucky. The Devonian black shales serve as both the source and trap for large quantities of natural gas; total gas in place for the shales in Kentucky is estimated to be between 63 and 112 trillion cubic feet. Most of this natural gas is adsorbed on clay and kerogen surfaces, analogous to the way methane is stored in coal beds. In coals, it has been demonstrated that CO{sub 2} is preferentially adsorbed, displacing methane at a ratio of two to one. Black shales may similarly desorb methane in the presence of CO{sub 2}. If black shales similarly desorb methane in the presence of CO{sub 2}, the shales may be an excellent sink for CO{sub 2} with the added benefit of serving to enhance natural gas production. The concept that black, organic-rich Devonian shales could serve as a significant geologic sink for CO{sub 2} is the subject this research. To accomplish this investigation, drill cuttings and cores will be selected from the Kentucky Geological Survey Well Sample and Core Library. CO{sub 2} adsorption analyses will be performed in order to determine the gas-storage potential of the shale and to identify shale facies with the most sequestration potential. In addition, new drill cuttings and sidewall core samples will be acquired to investigate specific black-shale facies, their uptake of CO{sub 2}, and the resultant displacement of methane. Advanced logging techniques (elemental capture spectroscopy) will be used to investigate possible correlations between adsorption capacity and geophysical log measurements.

  18. ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

    SciTech Connect (OSTI)

    Brandon C. Nuttall

    2003-02-11T23:59:59.000Z

    Proposed carbon management technologies include geologic sequestration of CO{sub 2}. A possible, but untested, strategy is to inject CO{sub 2} into organic-rich shales of Devonian age. Devonian black shales underlie approximately two-thirds of Kentucky and are generally thicker and deeper in the Illinois and Appalachian Basin portions of Kentucky. The Devonian black shales serve as both the source and trap for large quantities of natural gas; total gas in place for the shales in Kentucky is estimated to be between 63 and 112 trillion cubic feet. Most of this natural gas is adsorbed on clay and kerogen surfaces, analogous to the way methane is stored in coal beds. In coals, it has been demonstrated that CO{sub 2} is preferentially adsorbed, displacing methane at a ratio of two to one. Black shales may similarly desorb methane in the presence of CO{sub 2}. If black shales similarly desorb methane in the presence of CO{sub 2}, the shales may be an excellent sink for CO{sub 2} with the added benefit of serving to enhance natural gas production. The concept that black, organic-rich Devonian shales could serve as a significant geologic sink for CO{sub 2} is the subject this research. To accomplish this investigation, drill cuttings and cores will be selected from the Kentucky Geological Survey Well Sample and Core Library. CO{sub 2} adsorption analyses will be performed in order to determine the gas-storage potential of the shale and to identify shale facies with the most sequestration potential. In addition, new drill cuttings and sidewall core samples will be acquired to investigate specific black-shale facies, their uptake of CO{sub 2}, and the resultant displacement of methane. Advanced logging techniques (elemental capture spectroscopy) will be used to investigate possible correlations between adsorption capacity and geophysical log measurements.

  19. ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

    SciTech Connect (OSTI)

    Brandon C. Nuttall

    2003-02-10T23:59:59.000Z

    Proposed carbon management technologies include geologic sequestration of CO{sub 2}. A possible, but untested, strategy is to inject CO{sub 2} into organic-rich shales of Devonian age. Devonian black shales underlie approximately two-thirds of Kentucky and are generally thicker and deeper in the Illinois and Appalachian Basin portions of Kentucky. The Devonian black shales serve as both the source and trap for large quantities of natural gas; total gas in place for the shales in Kentucky is estimated to be between 63 and 112 trillion cubic feet. Most of this natural gas is adsorbed on clay and kerogen surfaces, analogous to the way methane is stored in coal beds. In coals, it has been demonstrated that CO{sub 2} is preferentially adsorbed, displacing methane at a ratio of two to one. Black shales may similarly desorb methane in the presence of CO{sub 2}. If black shales similarly desorb methane in the presence of CO{sub 2}, the shales may be an excellent sink for CO{sub 2} with the added benefit of serving to enhance natural gas production. The concept that black, organic-rich Devonian shales could serve as a significant geologic sink for CO{sub 2} is the subject this research. To accomplish this investigation, drill cuttings and cores will be selected from the Kentucky Geological Survey Well Sample and Core Library. CO{sub 2} adsorption analyses will be performed in order to determine the gas-storage potential of the shale and to identify shale facies with the most sequestration potential. In addition, new drill cuttings and sidewall core samples will be acquired to investigate specific black-shale facies, their uptake of CO{sub 2}, and the resultant displacement of methane. Advanced logging techniques (elemental capture spectroscopy) will be used to investigate possible correlations between adsorption capacity and geophysical log measurements.

  20. Biomass burning contribution to black carbon in the Western United States Mountain Ranges

    E-Print Network [OSTI]

    2011-01-01T23:59:59.000Z

    and the atmosphere from biomass burning, Climatic Change, 2,Chemistry and Physics Biomass burning contribution to black2011 Y. H. Mao et al. : Biomass burning contribution to

  1. Black hole soft X-ray transients: evolution of the cool disk and mass supply for the ADAF

    E-Print Network [OSTI]

    E. Meyer-Hofmeister; F. Meyer

    1999-06-18T23:59:59.000Z

    Using the black hole transient X-ray source A0620-00 as an example we study the physical interplay of three theoretical constituents for modelling these transient sources: (1) the advection-dominated accretion flow (ADAF) onto the central black hole, (2) the evaporation of matter from the cool outer disk forming a coronal flow and (3) standard disk evolution leading to outburst cycles by accretion disk instability (dwarf nova mechanism). We investigate the evolution of accretion disks during quiescence including the evaporation of gas in the inner part of the disk. About 20% of the matter is lost in a wind from the corona. The mass flow rate obtained from our model for the coronal flow towards the black hole, is about half of the matter flowing over from the companion star. It agrees with the rate independently derived from the ADAF spectral fits by Narayan et al. (1997). About one third of the matter accumulates in the outer cool disk. The computed disk evolution is consistent with the observational data from the outburst in 1975. The evolution of the accretion disk until the instability is reached shows that the critical surface density can not be reached for rates only slightly less than the rate derived here for A0620-00. Systems with such accretion rates would be globally stable, suggesting that many such faint permanently quiescent black hole X-ray binaries exist.

  2. ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

    SciTech Connect (OSTI)

    Brandon C. Nuttall

    2003-07-28T23:59:59.000Z

    CO{sub 2} emissions from the combustion of fossil fuels have been linked to global climate change. Proposed carbon management technologies include geologic sequestration of CO{sub 2}. A possible, but untested, sequestration strategy is to inject CO{sub 2} into organic-rich shales. Devonian black shales underlie approximately two-thirds of Kentucky and are thicker and deeper in the Illinois and Appalachian Basin portions of Kentucky than in central Kentucky. The Devonian black shales serve as both the source and trap for large quantities of natural gas; total gas in place for the shales in Kentucky is estimated to be between 63 and 112 trillion cubic feet. Most of this natural gas is adsorbed on clay and kerogen surfaces, analogous to methane storage in coal beds. In coals, it has been demonstrated that CO{sub 2} is preferentially adsorbed, displacing methane. Black shales may similarly desorb methane in the presence of CO{sub 2}. The concept that black, organic-rich Devonian shales could serve as a significant geologic sink for CO{sub 2} is the subject of current research. To accomplish this investigation, drill cuttings and cores were selected from the Kentucky Geological Survey Well Sample and Core Library. Methane and carbon dioxide adsorption analyses are being performed to determine the gas-storage potential of the shale and to identify shale facies with the most sequestration potential. In addition, sidewall core samples are being acquired to investigate specific black-shale facies, their potential CO{sub 2} uptake, and the resulting displacement of methane. Advanced logging techniques (elemental capture spectroscopy) are being investigated for possible correlations between adsorption capacity and geophysical log measurements. Initial estimates indicate a sequestration capacity of 5.3 billion tons CO{sub 2} in the Lower Huron Member of the Ohio shale in parts of eastern Kentucky and as much as 28 billion tons total in the deeper and thicker portions of the Devonian shales in Kentucky. Should the black shales of Kentucky prove to be a viable geologic sink for CO{sub 2}, their extensive occurrence in Paleozoic basins across North America would make them an attractive regional target for economic CO{sub 2} storage and enhanced natural gas production.

  3. The powerful jet of an off-nuclear intermediate-mass black hole in the spiral galaxy NGC 2276

    E-Print Network [OSTI]

    Mezcua, M; Lobanov, A P; Sutton, A D

    2015-01-01T23:59:59.000Z

    Jet ejection by accreting black holes is a mass invariant mechanism unifying stellar and supermassive black holes (SMBHs) that should also apply for intermediate-mass black holes (IMBHs), which are thought to be the seeds from which SMBHs form. We present the detection of an off-nuclear IMBH of $\\sim$5 $\\times$ 10$^{4}$ M$_\\odot$ located in an unusual spiral arm of the galaxy NGC 2276 based on quasi-simultaneous \\textit{Chandra} X-ray observations and European VLBI Network (EVN) radio observations. The IMBH, NGC2276-3c, possesses a 1.8 pc radio jet that is oriented in the same direction as large-scale ($\\sim$650 pc) radio lobes and whose emission is consistent with flat to optically thin synchrotron emission between 1.6 GHz and 5 GHz. Its jet kinetic power ($4 \\times 10^{40}$ erg s$^{-1}$) is comparable to its radiative output and its jet efficiency ($\\geq$ 46\\%) is as large as that of SMBHs. A region of $\\sim$300 pc along the jet devoid of young stars could provide observational evidence of jet feedback from...

  4. Synchrotron X-ray Scattering; Sensile Strength and Strain-Induced Crystallization in Carbon Black Filled Natural Rubber

    SciTech Connect (OSTI)

    Toki,S.; Minouchi, N.; Sics, I.; Hsiao, B.; Kohjiya, S.

    2008-01-01T23:59:59.000Z

    The tensile strength of rubber depends on a combination of contributions, in particular on the finite extensibility of chain segments between network points and on strain-induced crystallization. In order to achieve high tensile strength at high strain at break, we optimized the composition and processing parameters to gain high molecular flexibility by the cure conditions, to acquire high flexibility of sulfur bridges by the accelerator, and to increase the modulus level without losing rubber molecule flexibility by carbon black. As a result, our formula performed a tensile strength of 42.5 MPa at 25 C under ISO-37, as officially measured by the Society of Rubber Industry, Japan, in 2004.

  5. Use of pyrolyzed carbon black as an additive (part 3. Air-cooled furnace slag). Final report

    SciTech Connect (OSTI)

    Lee, K.H.; Lovell, C.W.; Salgado, R.

    1996-11-20T23:59:59.000Z

    Scrap tires, generated at the rate of over 242 million each year in the United States, are recognized as one of the most significant environmental problems. Most of these scrap tires have been disposed of in landfills, stockpiles, and illegal dumps (EPA 1991). There is a need to find more useful, environmentally friendly applications for these tires. Extensive researches have been conducted in the past years on the utilization of the scrap tires. The use of scrap tires for asphalt pavement, which is complicated by the complex behavior of asphalt, has received major attention. This research aims to describe the performance of mixtures of asphalt using pyrolyzed carbon black as an additive.

  6. Black Carbon and Kerosene Lighting: An Opportunity for Rapid Action on Climate Change and Clean Energy for Development

    SciTech Connect (OSTI)

    Jacobson, Arne [Humboldt State Univ., MN (United States). Schatz Energy Research Center; Bond, Tami C. [Univ. of Illinois at Urbana-Champaign, IL (United States). Dept. of Civil and Environmental Engineering; Lam, Nicholoas L. [Univ. of California, Berkeley, CA (United States). Dept. of Environmental Health Sciences; Hultman, Nathan [The Brookings Institution, Washington, DC (United States)

    2013-04-15T23:59:59.000Z

    Replacing inefficient kerosene lighting with electric lighting or other clean alternatives can rapidly achieve development and energy access goals, save money and reduce climate warming. Many of the 250 million households that lack reliable access to electricity rely on inefficient and dangerous simple wick lamps and other kerosene-fueled light sources, using 4 to 25 billion liters of kerosene annually to meet basic lighting needs. Kerosene costs can be a significant household expense and subsidies are expensive. New information on kerosene lamp emissions reveals that their climate impacts are substantial. Eliminating current annual black carbon emissions would provide a climate benefit equivalent to 5 gigatons of carbon dioxide reductions over the next 20 years. Robust and low-cost technologies for supplanting simple wick and other kerosene-fueled lamps exist and are easily distributed and scalable. Improving household lighting offers a low-cost opportunity to improve development, cool the climate and reduce costs.

  7. GRB060218 AS A TIDAL DISRUPTION OF A WHITE DWARF BY AN INTERMEDIATE-MASS BLACK HOLE

    SciTech Connect (OSTI)

    Shcherbakov, Roman V.; Reynolds, Christopher S. [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); Pe'er, Asaf [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Haas, Roland [Theoretical AstroPhysics Including Relativity, California Institute of Technology, Pasadena, CA 91125 (United States); Bode, Tanja; Laguna, Pablo [Center for Relativistic Astrophysics, School of Physics, Georgia Institute of Technology, Atlanta, GA 30332 (United States)

    2013-06-01T23:59:59.000Z

    The highly unusual pair of a gamma-ray burst (GRB) GRB060218 and an associated supernova, SN2006aj, has puzzled theorists for years. A supernova shock breakout and a jet from a newborn stellar mass compact object have been proposed to explain this pair's multiwavelength signature. Alternatively, we propose that the source is naturally explained by another channel: the tidal disruption of a white dwarf (WD) by an intermediate-mass black hole (IMBH). This tidal disruption is accompanied by a tidal pinching, which leads to the ignition of a WD and a supernova. Some debris falls back onto the IMBH, forms a disk, which quickly amplifies the magnetic field, and launches a jet. We successfully fit soft X-ray spectra with the Comptonized blackbody emission from a jet photosphere. The optical/UV emission is consistent with self-absorbed synchrotron emission from the expanding jet front. The temporal dependence of the accretion rate M-dot (t) in a tidal disruption provides a good fit to the soft X-ray light curve. The IMBH mass is found to be about 10{sup 4} M{sub Sun} in three independent estimates: (1) fitting the tidal disruption M-dot (t) to the soft X-ray light curve, (2) computing the jet base radius in a jet photospheric emission model, and (3) inferring the mass of the central black hole based on the host dwarf galaxy's stellar mass. The position of the supernova is consistent with the center of the host galaxy, while the low supernova ejecta mass is consistent with that of a WD. The high expected rate of tidal disruptions in dwarf galaxies is consistent with one source observed by the Swift satellite over several years at a distance of 150 Mpc measured for GRB060218. Encounters with WDs provide much fuel for the growth of IMBHs.

  8. Cosmic Evolution of Black Holes and Spheroids. V. The Relation Between Black Hole Mass and Host Galaxy Luminosity for a Sample of 79 Active Galaxies

    E-Print Network [OSTI]

    Park, Daeseong; Bennert, Vardha N; Treu, Tommaso; Auger, Matthew W; Malkan, Matthew A

    2014-01-01T23:59:59.000Z

    We investigate the cosmic evolution of the black hole (BH) mass -- bulge luminosity relation using a sample of 52 active galaxies at $z \\sim 0.36$ and $z \\sim 0.57$ in the BH mass range of $10^{7.4-9.1} M_{\\odot}$. By consistently applying multi-component spectral and structural decomposition to high-quality Keck spectra and high-resolution HST images, BH masses ($M_{\\rm BH}$) are estimated using the H$\\beta$ broad emission line combined with the 5100 \\AA\\ nuclear luminosity, and bulge luminosities ($L_{\\rm bul}$) are derived from surface photometry. Comparing the resulting $M_{\\rm BH}-L_{\\rm bul}$ relation to local active galaxies and taking into account selection effects, we find evolution of the form $M_{\\rm BH} / L_{\\rm bul} \\propto (1+z)^{\\gamma}$ with $\\gamma=1.8\\pm0.7$, consistent with BH growth preceding that of the host galaxies. Including an additional sample of 27 active galaxies with $0.5

  9. A 400 solar mass black hole in the Ultraluminous X-ray source M82 X-1 accreting close to its Eddington limit

    E-Print Network [OSTI]

    Pasham, Dheeraj R; Mushotzky, Richard F

    2015-01-01T23:59:59.000Z

    M82 X-1, the brightest X-ray source in the galaxy M82, has been thought to be an intermediate-mass black hole (100 to 10,000 solar masses) because of its extremely high luminosity and variability characteristics, although some models suggest that its mass may be only about 20 solar masses. The previous mass estimates were based on scaling relations that use low-frequency characteristic timescales which have large intrinsic uncertainties. For stellar-mass black holes, we know that the high-frequency quasi-periodic oscillations (100-450 hertz) in the X-ray emission that occur in a 3:2 frequency ratio are stable and scale in frequency inversely with black hole mass with a reasonably small dispersion. The discovery of such stable oscillations thus potentially offers an alternative and less ambiguous means of mass determination for intermediate-mass black holes, but has hitherto not been realized. Here we report stable, twin-peak (3:2 frequency ratio) X-ray quasi-periodic oscillations from M82 X-1 at frequencies o...

  10. Pulmonary function and symptoms of Nigerian workers exposed to carbon black in dry cell battery and tire factories

    SciTech Connect (OSTI)

    Oleru, U.G.; Elegbeleye, O.O.; Enu, C.C.; Olumide, Y.M.

    1983-02-01T23:59:59.000Z

    The pulmonary function and symptoms of 125 workers exposed to carbon black in dry cell battery and tire manufacturing plants were investigated. There was no significant difference in the pulmonary function of the subjects in the two plants. There was good agreement in the symptoms reported in the two different factories: cough with phlegm production, tiredness, chest pain, catarrh, headache, and skin irritation. The symptoms also corroborate those reported in the few studies on the pulmonary effects of carbon black. The suspended particulate levels in the dry cell battery plant ranged from 25 to 34 mg/m/sup 3/ and the subjects with the highest probable exposure level had the most impaired pulmonary function. The pulmonary function of the exposed subjects was significantly lower than that of a control, nonindustrially exposed population. The drop in the lung function from the expected value per year of age was relatively constant for all the study subgroups but the drop per year of duration of employment was more severe in the earlier years of employment. This study has underscored the need for occupational health regulations in the industries of developing countries.

  11. Search for gravitational wave ringdowns from perturbed intermediate mass black holes in LIGO-Virgo data from 2005-2010

    E-Print Network [OSTI]

    The LIGO Scientific Collaboration; the Virgo Collaboration; J. Aasi; B. P. Abbott; R. Abbott; T. Abbott; M. R. Abernathy; F. Acernese; K. Ackley; C. Adams; T. Adams; P. Addesso; R. X. Adhikari; C. Affeldt; M. Agathos; N. Aggarwal; O. D. Aguiar; A. Ain; P. Ajith; A. Alemic; B. Allen; A. Allocca; D. Amariutei; M. Andersen; R. Anderson; S. B. Anderson; W. G. Anderson; K. Arai; M. C. Araya; C. Arceneaux; J. Areeda; S. M. Aston; P. Astone; P. Aufmuth; C. Aulbert; L. Austin; B. E. Aylott; S. Babak; P. T. Baker; G. Ballardin; S. W. Ballmer; J. C. Barayoga; M. Barbet; B. C. Barish; D. Barker; F. Barone; B. Barr; L. Barsotti; M. Barsuglia; M. A. Barton; I. Bartos; R. Bassiri; A. Basti; J. C. Batch; J. Bauchrowitz; Th. S. Bauer; V. Bavigadda; B. Behnke; M. Bejger; M . G. Beker; C. Belczynski; A. S. Bell; C. Bell; M. Benacquista; G. Bergmann; D. Bersanetti; A. Bertolini; J. Betzwieser; P. T. Beyersdorf; I. A. Bilenko; G. Billingsley; J. Birch; S. Biscans; M. Bitossi; M. A. Bizouard; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; S. Bloemen; O. Bock; T. P. Bodiya; M. Boer; G. Bogaert; C. Bogan; C. Bond; F. Bondu; L. Bonelli; R. Bonnand; R. Bork; M. Born; V. Boschi; Sukanta Bose; L. Bosi; C. Bradaschia; P. R. Brady; V. B. Braginsky; M. Branchesi; J. E. Brau; T. Briant; D. O. Bridges; A. Brillet; M. Brinkmann; V. Brisson; A. F. Brooks; D. A. Brown; D. D. Brown; F. Brückner; S. Buchman; T. Bulik; H. J. Bulten; A. Buonanno; R. Burman; D. Buskulic; C. Buy; L. Cadonati; G. Cagnoli; J. Calderón Bustillo; E. Calloni; J. B. Camp; P. Campsie; K. C. Cannon; B. Canuel; J. Cao; C. D. Capano; F. Carbognani; L. Carbone; S. Caride; A. Castiglia; S. Caudill; M. Cavagliŕ; F. Cavalier; R. Cavalieri; C. Celerier; G. Cella; C. Cepeda; E. Cesarini; R. Chakraborty; T. Chalermsongsak; S. J. Chamberlin; S. Chao; P. Charlton; E. Chassande-Mottin; X. Chen; Y. Chen; A. Chincarini; A. Chiummo; H. S. Cho; J. Chow; N. Christensen; Q. Chu; S. S. Y. Chua; S. Chung; G. Ciani; F. Clara; J. A. Clark; F. Cleva; E. Coccia; P. -F. Cohadon; A. Colla; C. Collette; M. Colombini; L. Cominsky; M. Constancio Jr.; A. Conte; D. Cook; T. R. Corbitt; M. Cordier; N. Cornish; A. Corpuz; A. Corsi; C. A. Costa; M. W. Coughlin; S. Coughlin; J. -P. Coulon; S. Countryman; P. Couvares; D. M. Coward; M. Cowart; D. C. Coyne; R. Coyne; K. Craig; J. D. E. Creighton; S. G. Crowder; A. Cumming; L. Cunningham; E. Cuoco; K. Dahl; T. Dal Canton; M. Damjanic; S. L. Danilishin; S. D'Antonio; K. Danzmann; V. Dattilo; H. Daveloza; M. Davier; G. S. Davies; E. J. Daw; R. Day; T. Dayanga; G. Debreczeni; J. Degallaix; S. Deléglise; W. Del Pozzo; T. Denker; T. Dent; H. Dereli; V. Dergachev; R. De Rosa; R. T. DeRosa; R. DeSalvo; S. Dhurandhar; M. Díaz; L. Di Fiore; A. Di Lieto; I. Di Palma; A. Di Virgilio; V. Dolique; A. Donath; F. Donovan; K. L. Dooley; S. Doravari; S. Dossa; R. Douglas; T. P. Downes; M. Drago; R. W. P. Drever; J. C. Driggers; Z. Du; M. Ducrot; S. Dwyer; T. Eberle; T. Edo; M. Edwards; A. Effler; H. Eggenstein; P. Ehrens; J. Eichholz; S. S. Eikenberry; G. Endr\\Hoczi; R. Essick; T. Etzel; M. Evans; T. Evans; M. Factourovich; V. Fafone; S. Fairhurst; Q. Fang; S. Farinon; B. Farr; W. M. Farr; M. Favata; H. Fehrmann; M. M. Fejer; D. Feldbaum; F. Feroz; I. Ferrante; F. Ferrini; F. Fidecaro; L. S. Finn; I. Fiori; R. P. Fisher; R. Flaminio; J. -D. Fournier; S. Franco; S. Frasca; F. Frasconi; M. Frede; Z. Frei; A. Freise; R. Frey; T. T. Fricke; P. Fritschel; V. V. Frolov; P. Fulda; M. Fyffe; J. Gair; L. Gammaitoni; S. Gaonkar; F. Garufi; N. Gehrels; G. Gemme; B. Gendre; E. Genin; A. Gennai; S. Ghosh; J. A. Giaime; K. D. Giardina; A. Giazotto; C. Gill; J. Gleason; E. Goetz; R. Goetz; L. M. Goggin; L. Gondan; G. González; N. Gordon; M. L. Gorodetsky; S. Gossan; S. Goßler; R. Gouaty; C. Gräf; P. B. Graff; M. Granata; A. Grant; S. Gras; C. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; P. Groot; H. Grote; K. Grover; S. Grunewald; G. M. Guidi; C. Guido; K. Gushwa; E. K. Gustafson; R. Gustafson; D. Hammer; G. Hammond; M. Hanke; J. Hanks; C. Hanna; J. Hanson; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; M. Hart; M. T. Hartman; C. -J. Haster; K. Haughian; A. Heidmann; M. Heintze; H. Heitmann; P. Hello; G. Hemming; M. Hendry; I. S. Heng; A. W. Heptonstall; M. Heurs; M. Hewitson; S. Hild; D. Hoak; K. A. Hodge; K. Holt; S. Hooper; P. Hopkins; D. J. Hosken; J. Hough; E. J. Howell; Y. Hu; B. Hughey; S. Husa; S. H. Huttner; M. Huynh; T. Huynh-Dinh; D. R. Ingram; R. Inta; T. Isogai; A. Ivanov; B. R. Iyer; K. Izumi; M. Jacobson; E. James; H. Jang; P. Jaranowski; Y. Ji; F. Jiménez-Forteza; W. W. Johnson; D. I. Jones; R. Jones; R. J. G. Jonker; L. Ju; K. Haris; P. Kalmus; V. Kalogera; S. Kandhasamy; G. Kang; J. B. Kanner; J. Karlen; M. Kasprzack; E. Katsavounidis; W. Katzman; H. Kaufer; K. Kawabe; F. Kawazoe; F. Kéfélian; G. M. Keiser; D. Keitel; D. B. Kelley

    2014-05-22T23:59:59.000Z

    We report results from a search for gravitational waves produced by perturbed intermediate mass black holes (IMBH) in data collected by LIGO and Virgo between 2005 and 2010. The search was sensitive to astrophysical sources that produced damped sinusoid gravitational wave signals, also known as ringdowns, with frequency $50\\le f_{0}/\\mathrm{Hz} \\le 2000$ and decay timescale $0.0001\\lesssim \\tau/\\mathrm{s} \\lesssim 0.1$ characteristic of those produced in mergers of IMBH pairs. No significant gravitational wave candidate was detected. We report upper limits on the astrophysical coalescence rates of IMBHs with total binary mass $50 \\le M/\\mathrm{M}_\\odot \\le 450$ and component mass ratios of either 1:1 or 4:1. For systems with total mass $100 \\le M/\\mathrm{M}_\\odot \\le 150$, we report a 90%-confidence upper limit on the rate of binary IMBH mergers with non-spinning and equal mass components of $6.9\\times10^{-8}\\,$Mpc$^{-3}$yr$^{-1}$. We also report a rate upper limit for ringdown waveforms from perturbed IMBHs, radiating 1% of their mass as gravitational waves in the fundamental, $\\ell=m=2$, oscillation mode, that is nearly three orders of magnitude more stringent than previous results.

  12. A systematic study of carbon-oxygen white dwarf mergers: mass combinations for Type Ia supernovae

    E-Print Network [OSTI]

    Sato, Yushi; Tanikawa, Ataru; Nomoto, Ken'ichi; Maeda, Keiichi; Hachisu, Izumi

    2015-01-01T23:59:59.000Z

    Mergers of two carbon-oxygen (CO) white dwarfs (WDs) have been considered as progenitors of Type Ia supernovae (SNe Ia). Based on smoothed particle hydrodynamics (SPH) simulations, previous studies claimed that mergers of CO WDs lead to an SN Ia explosion either in the dynamical merger phase or stationary rotating merger remnant phase. However, the mass range of CO WDs that lead to an SN Ia has not been clearly identified yet. In the present work, we perform systematic SPH merger simulations for the WD masses ranging from $0.5~M_{\\odot}$ to $1.1~M_{\\odot}$ with higher resolutions than the previous systematic surveys and examine whether or not carbon burning occurs dynamically or quiescently in each phase. We further study the possibility of SN Ia explosion and estimate the mass range of CO WDs that lead to an SN Ia. We found that when the both WDs are massive, i.e., in the mass range of $0.9~M_{\\odot} {\\le} M_{1,2} {\\le} 1.1~M_{\\odot}$, they can explode as an SN Ia in the merger phase. On the other hand, when...

  13. Low temperature growth of ultra-high mass density carbon nanotube forests on conductive supports

    SciTech Connect (OSTI)

    Sugime, Hisashi; Esconjauregui, Santiago; Yang, Junwei; D'Arsié, Lorenzo; Robertson, John [Department of Engineering, University of Cambridge, Cambridge CB3 0FA (United Kingdom)] [Department of Engineering, University of Cambridge, Cambridge CB3 0FA (United Kingdom); Oliver, Rachel A. [Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CB2 0FS (United Kingdom)] [Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CB2 0FS (United Kingdom); Bhardwaj, Sunil [Istituto Officina dei Materiali-CNR, Laboratorio TASC, Trieste I-34149 (Italy) [Istituto Officina dei Materiali-CNR, Laboratorio TASC, Trieste I-34149 (Italy); Sincrotrone Trieste S.C.p.A., Strada Statale 14, Km 163.5, Trieste I-34149 (Italy); Cepek, Cinzia [Istituto Officina dei Materiali-CNR, Laboratorio TASC, Trieste I-34149 (Italy)] [Istituto Officina dei Materiali-CNR, Laboratorio TASC, Trieste I-34149 (Italy)

    2013-08-12T23:59:59.000Z

    We grow ultra-high mass density carbon nanotube forests at 450 °C on Ti-coated Cu supports using Co-Mo co-catalyst. X-ray photoelectron spectroscopy shows Mo strongly interacts with Ti and Co, suppressing both aggregation and lifting off of Co particles and, thus, promoting the root growth mechanism. The forests average a height of 0.38 ?m and a mass density of 1.6 g cm{sup ?3}. This mass density is the highest reported so far, even at higher temperatures or on insulators. The forests and Cu supports show ohmic conductivity (lowest resistance ?22 k?), suggesting Co-Mo is useful for applications requiring forest growth on conductors.

  14. Search for gravitational wave ringdowns from perturbed intermediate mass black holes in LIGO-Virgo data from 2005-2010

    E-Print Network [OSTI]

    Aasi, J; Abbott, R; Abbott, T; Abernathy, M R; Acernese, F; Ackley, K; Adams, C; Adams, T; Addesso, P; Adhikari, R X; Affeldt, C; Agathos, M; Aggarwal, N; Aguiar, O D; Ain, A; Ajith, P; Alemic, A; Allen, B; Allocca, A; Amariutei, D; Andersen, M; Anderson, R; Anderson, S B; Anderson, W G; Arai, K; Araya, M C; Arceneaux, C; Areeda, J; Aston, S M; Astone, P; Aufmuth, P; Aulbert, C; Austin, L; Aylott, B E; Babak, S; Baker, P T; Ballardin, G; Ballmer, S W; Barayoga, J C; Barbet, M; Barish, B C; Barker, D; Barone, F; Barr, B; Barsotti, L; Barsuglia, M; Barton, M A; Bartos, I; Bassiri, R; Basti, A; Batch, J C; Bauchrowitz, J; Bauer, Th S; Bavigadda, V; Behnke, B; Bejger, M; Beker, M G; Belczynski, C; Bell, A S; Bell, C; Benacquista, M; Bergmann, G; Bersanetti, D; Bertolini, A; Betzwieser, J; Beyersdorf, P T; Bilenko, I A; Billingsley, G; Birch, J; Biscans, S; Bitossi, M; Bizouard, M A; Black, E; Blackburn, J K; Blackburn, L; Blair, D; Bloemen, S; Bock, O; Bodiya, T P; Boer, M; Bogaert, G; Bogan, C; Bond, C; Bondu, F; Bonelli, L; Bonnand, R; Bork, R; Born, M; Boschi, V; Bose, Sukanta; Bosi, L; Bradaschia, C; Brady, P R; Braginsky, V B; Branchesi, M; Brau, J E; Briant, T; Bridges, D O; Brillet, A; Brinkmann, M; Brisson, V; Brooks, A F; Brown, D A; Brown, D D; Brückner, F; Buchman, S; Bulik, T; Bulten, H J; Buonanno, A; Burman, R; Buskulic, D; Buy, C; Cadonati, L; Cagnoli, G; Bustillo, J Calderón; Calloni, E; Camp, J B; Campsie, P; Cannon, K C; Canuel, B; Cao, J; Capano, C D; Carbognani, F; Carbone, L; Caride, S; Castiglia, A; Caudill, S; Cavagliŕ, M; Cavalier, F; Cavalieri, R; Celerier, C; Cella, G; Cepeda, C; Cesarini, E; Chakraborty, R; Chalermsongsak, T; Chamberlin, S J; Chao, S; Charlton, P; Chassande-Mottin, E; Chen, X; Chen, Y; Chincarini, A; Chiummo, A; Cho, H S; Chow, J; Christensen, N; Chu, Q; Chua, S S Y; Chung, S; Ciani, G; Clara, F; Clark, J A; Cleva, F; Coccia, E; Cohadon, P -F; Colla, A; Collette, C; Colombini, M; Cominsky, L; Constancio, M; Conte, A; Cook, D; Corbitt, T R; Cordier, M; Cornish, N; Corpuz, A; Corsi, A; Costa, C A; Coughlin, M W; Coughlin, S; Coulon, J -P; Countryman, S; Couvares, P; Coward, D M; Cowart, M; Coyne, D C; Coyne, R; Craig, K; Creighton, J D E; Crowder, S G; Cumming, A; Cunningham, L; Cuoco, E; Dahl, K; Canton, T Dal; Damjanic, M; Danilishin, S L; D'Antonio, S; Danzmann, K; Dattilo, V; Daveloza, H; Davier, M; Davies, G S; Daw, E J; Day, R; Dayanga, T; Debreczeni, G; Degallaix, J; Deléglise, S; Del Pozzo, W; Denker, T; Dent, T; Dereli, H; Dergachev, V; De Rosa, R; DeRosa, R T; DeSalvo, R; Dhurandhar, S; Díaz, M; Di Fiore, L; Di Lieto, A; Di Palma, I; Di Virgilio, A; Dolique, V; Donath, A; Donovan, F; Dooley, K L; Doravari, S; Dossa, S; Douglas, R; Downes, T P; Drago, M; Drever, R W P; Driggers, J C; Du, Z; Ducrot, M; Dwyer, S; Eberle, T; Edo, T; Edwards, M; Effler, A; Eggenstein, H; Ehrens, P; Eichholz, J; Eikenberry, S S; Endr?czi, G; Essick, R; Etzel, T; Evans, M; Evans, T; Factourovich, M; Fafone, V; Fairhurst, S; Fang, Q; Farinon, S; Farr, B; Farr, W M; Favata, M; Fehrmann, H; Fejer, M M; Feldbaum, D; Feroz, F; Ferrante, I; Ferrini, F; Fidecaro, F; Finn, L S; Fiori, I; Fisher, R P; Flaminio, R; Fournier, J -D; Franco, S; Frasca, S; Frasconi, F; Frede, M; Frei, Z; Freise, A; Frey, R; Fricke, T T; Fritschel, P; Frolov, V V; Fulda, P; Fyffe, M; Gair, J; Gammaitoni, L; Gaonkar, S; Garufi, F; Gehrels, N; Gemme, G; Gendre, B; Genin, E; Gennai, A; Ghosh, S; Giaime, J A; Giardina, K D; Giazotto, A; Gill, C; Gleason, J; Goetz, E; Goetz, R; Goggin, L M; Gondan, L; González, G; Gordon, N; Gorodetsky, M L; Gossan, S; Goßler, S; Gouaty, R; Gräf, C; Graff, P B; Granata, M; Grant, A; Gras, S; Gray, C; Greenhalgh, R J S; Gretarsson, A M; Groot, P; Grote, H; Grover, K; Grunewald, S; Guidi, G M; Guido, C; Gushwa, K; Gustafson, E K; Gustafson, R; Hammer, D; Hammond, G; Hanke, M; Hanks, J; Hanna, C; Hanson, J; Harms, J; Harry, G M; Harry, I W; Harstad, E D; Hart, M; Hartman, M T; Haster, C -J; Haughian, K; Heidmann, A; Heintze, M; Heitmann, H; Hello, P; Hemming, G; Hendry, M; Heng, I S; Heptonstall, A W; Heurs, M; Hewitson, M; Hild, S; Hoak, D; Hodge, K A; Holt, K; Hooper, S; Hopkins, P; Hosken, D J; Hough, J; Howell, E J; Hu, Y; Hughey, B; Husa, S; Huttner, S H; Huynh, M; Huynh-Dinh, T; Ingram, D R; Inta, R; Isogai, T; Ivanov, A; Iyer, B R; Izumi, K; Jacobson, M; James, E; Jang, H; Jaranowski, P; Ji, Y; Jiménez-Forteza, F; Johnson, W W; Jones, D I; Jones, R; Jonker, R J G; Ju, L; Haris, K; Kalmus, P; Kalogera, V; Kandhasamy, S; Kang, G; Kanner, J B; Karlen, J; Kasprzack, M; Katsavounidis, E; Katzman, W; Kaufer, H; Kawabe, K; Kawazoe, F; Kéfélian, F; Keiser, G M; Keitel, D; Kelley, D B; Kells, W; Khalaidovski, A; Khalili, F Y; Khazanov, E A; Kim, C; Kim, K; Kim, N; Kim, N G; Kim, Y -M; King, E J; King, P J; Kinzel, D L; Kissel, J S; Klimenko, S; Kline, J; Koehlenbeck, S; Kokeyama, K

    2014-01-01T23:59:59.000Z

    We report results from a search for gravitational waves produced by perturbed intermediate mass black holes (IMBH) in data collected by LIGO and Virgo between 2005 and 2010. The search was sensitive to astrophysical sources that produced damped sinusoid gravitational wave signals, also known as ringdowns, with frequency $50\\le f_{0}/\\mathrm{Hz} \\le 2000$ and decay timescale $0.0001\\lesssim \\tau/\\mathrm{s} \\lesssim 0.1$ characteristic of those produced in mergers of IMBH pairs. No significant gravitational wave candidate was detected. We report upper limits on the astrophysical coalescence rates of IMBHs with total binary mass $50 \\le M/\\mathrm{M}_\\odot \\le 450$ and component mass ratios of either 1:1 or 4:1. For systems with total mass $100 \\le M/\\mathrm{M}_\\odot \\le 150$, we report a 90%-confidence upper limit on the rate of binary IMBH mergers with non-spinning and equal mass components of $6.9\\times10^{-8}\\,$Mpc$^{-3}$yr$^{-1}$. We also report a rate upper limit for ringdown waveforms from perturbed IMBHs,...

  15. An AeroCom Assessment of Black Carbon in Arctic Snow and Sea Ice

    SciTech Connect (OSTI)

    Jiao, C.; Flanner, M. G.; Balkanski, Y.; Bauer, S.; Bellouin, N.; Berntsen, T.; Bian, Huisheng; Carslaw, K. S.; Chin, Mian; De Luca, N.; Diehl, Thomas; Ghan, Steven J.; Iversen, T.; Kirkevag, A.; Koch, Dorothy; Liu, Xiaohong; Mann, G. W.; Penner, Joyce E.; Pitari, G.; Schulz, M.; Seland, O.; Skeie, R. B.; Steenrod, Stephen D.; Stier, P.; Takemura, T.; Tsigaridis, Kostas; van Noije, T.; Yun, Yuxing; Zhang, Kai

    2014-03-07T23:59:59.000Z

    Though many global aerosols models prognose surface deposition, only a few models have been used to directly simulate the radiative effect from black carbon (BC) deposition to snow and sea-ice. Here, we apply aerosol deposition fields from 25 models contributing to two phases of the Aerosol Comparisons between Observations and Models (AeroCom) project to simulate and evaluate within snow BC concentrations and radiative effect in the Arctic. We accomplish this by driving the offline land and sea-ice components of the Community Earth System Model with different deposition fields and meteorological conditions from 2004-2009, during which an extensive field campaign of BC measurements in Arctic snow occurred. We find that models generally underestimate BC concentrations in snow in northern Russia and Norway, while overestimating BC amounts elsewhere in the Arctic. Although simulated BC distributions in snow are poorly correlated with measurements, mean values are reasonable. The multi-model mean (range) bias in BC concentrations, sampled over the same grid cells, snow depths, and months of measurements, are -4.4 (-13.2 to +10.7) ng g?1 for an earlier Phase of AeroCom models (Phase I), and +4.1 (-13.0 to +21.4) ng g?1 for a more recent Phase of AeroCom models (Phase II), compared to the observational mean of 19.2 ng g?1. Factors determining model BC concentrations in Arctic snow include Arctic BC emissions, transport of extra-Arctic aerosols, precipitation, deposition efficiency of aerosols within the Arctic, and meltwater removal of particles in snow. Sensitivity studies show that the model–measurement evaluation is only weakly affected by meltwater scavenging efficiency because most measurements were conducted in non-melting snow. The Arctic (60-90?N) atmospheric residence time for BC in Phase II models ranges from 3.7 to 23.2 days, implying large inter-model variation in local BC deposition efficiency. Combined with the fact that most Arctic BC deposition originates from extra-Arctic emissions, these results suggest that aerosol removal processes are a leading source of variation in model performance. The multi-model mean (full range) of Arctic radiative effect from BC in snow is 0.15 (0.07-0.25) W m?2 and 0.18 (0.06-0.28) W m?2 in Phase I and Phase II models, respectively. After correcting for model biases relative to observed BC concentrations in different regions of the Arctic, we obtain a multi-model mean Arctic radiative effect of 0.17 W m?2 for the combined AeroCom ensembles. Finally, there is a high correlation between modeled BC concentrations sampled over the observational sites and the Arctic as a whole, indicating that the field campaign provided a reasonable sample of the Arctic.

  16. Radiation drag driven mass accretion in clumpy interstellar medium: implications for the supermassive black hole-to-bulge relation

    E-Print Network [OSTI]

    Nozomu Kawakatu; Masayuki Umemura

    2001-11-22T23:59:59.000Z

    We quantitatively scrutinize the effects of the radiation drag arising from the radiation fields in a galactic bulge in order to examine the possibility that the radiation drag could be an effective mechanism to extract angular momentum in a spheroidal system like a bulge and allow plenty of gas to accrete onto the galactic center. For this purpose, we numerically solve the relativistic radiation hydrodynamical equation coupled with the accurate radiative transfer and quantitatively assess the radiation drag efficiency. As a result, we find that in an optically thick regime the radiation drag efficiency is sensitively dependent on the density distributions of interstellar medium (ISM). The efficiency drops according to $\\tau_{\\rm T}^{-2}$ in an optically thick {\\it uniform} ISM, where $\\tau_{\\rm T}$ is the total optical depth of the dusty ISM, whereas the efficiency remains almost constant at a high level if the ISM is {\\it clumpy}. Hence, if the bulge formation begins with a star formation event in a clumpy ISM, the radiation drag will effectively work to remove the angular momentum and the accreted gas may form a supermassive black hole. As a natural consequence, this mechanism reproduces a putative linear relation between the mass of a supermassive black hole and the mass of a galactic bulge, although further detailed modeling for stellar evolution is required for the more precise prediction.

  17. MONTE CARLO SIMULATIONS OF GLOBULAR CLUSTER EVOLUTION. VI. THE INFLUENCE OF AN INTERMEDIATE-MASS BLACK HOLE

    SciTech Connect (OSTI)

    Umbreit, Stefan; Rasio, Frederic A. [Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA) and Department of Physics and Astronomy, Northwestern University, 2145 Sheridan Rd., Evanston, IL 60208 (United States); Fregeau, John M. [Kavli Institute of Theoretical Physics, University of California, Santa Barbara, CA 93106 (United States); Chatterjee, Sourav, E-mail: s-umbreit@northwestern.edu [Department of Astronomy, University of Florida, 211 Bryant Space Science Center, Gainesville, FL (United States)

    2012-05-01T23:59:59.000Z

    We present results from a series of Monte Carlo (MC) simulations investigating the imprint of a central intermediate-mass black hole (IMBH) on the structure of a globular cluster. We investigate the three-dimensional and projected density profiles, and stellar disruption rates for idealized as well as realistic cluster models, taking into account a stellar mass spectrum and stellar evolution, and allowing for a larger, more realistic number of stars than was previously possible with direct N-body methods. We compare our results to other N-body and Fokker-Planck simulations published previously. We find, in general, very good agreement for the overall cluster structure and dynamical evolution between direct N-body simulations and our MC simulations. Significant differences exist in the number of stars that are tidally disrupted by the IMBH, and this is most likely caused by the wandering motion of the IMBH, not included in the MC scheme. These differences, however, are negligible for the final IMBH masses in realistic cluster models, as the disruption rates are generally much lower than for single-mass clusters. As a direct comparison to observations we construct a detailed model for the cluster NGC 5694, which is known to possess a central surface brightness cusp consistent with the presence of an IMBH. We find that not only the inner slope but also the outer part of the surface brightness profile agree well with observations. However, there is only a slight preference for models harboring an IMBH compared to models without.

  18. Black carbon in marine sediments : quantification and implications for the sorption of polycyclic aromatic hydrocarbons

    E-Print Network [OSTI]

    Accardi-Dey, AmyMarie, 1976-

    2003-01-01T23:59:59.000Z

    Sorption is a key factor in determining the fate of polycyclic aromatic hydrocarbons (PAHs) in the environment. Here, PAH sorption is proposed as the sum of two mechanisms: absorption into a biogenic, organic carbon (OC) ...

  19. ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

    SciTech Connect (OSTI)

    Brandon C. Nuttall

    2005-04-26T23:59:59.000Z

    Devonian gas shales underlie approximately two-thirds of Kentucky. In the shale, natural gas is adsorbed on clay and kerogen surfaces. This is analogous to methane storage in coal beds, where CO{sub 2} is preferentially adsorbed, displacing methane. Black shales may similarly desorb methane in the presence of CO{sub 2}. Drill cuttings from the Kentucky Geological Survey Well Sample and Core Library were sampled to determine CO{sub 2} and CH{sub 4} adsorption isotherms. Sidewall core samples were acquired to investigate CO{sub 2} displacement of methane. An elemental capture spectroscopy log was acquired to investigate possible correlations between adsorption capacity and mineralogy. Average random vitrinite reflectance data range from 0.78 to 1.59 (upper oil to wet gas and condensate hydrocarbon maturity range). Total organic content determined from acid-washed samples ranges from 0.69 to 14 percent. CO{sub 2} adsorption capacities at 400 psi range from a low of 14 scf/ton in less organic-rich zones to more than 136 scf/ton. There is a direct correlation between measured total organic carbon content and the adsorptive capacity of the shale; CO{sub 2} adsorption capacity increases with increasing organic carbon content. Initial estimates based on these data indicate a sequestration capacity of 5.3 billion tons of CO{sub 2} in the Lower Huron Member of the Ohio Shale of eastern Kentucky and as much as 28 billion tons total in the deeper and thicker parts of the Devonian shales in Kentucky. Should the black shales of Kentucky prove to be a viable geologic sink for CO{sub 2}, their extensive occurrence in Paleozoic basins across North America would make them an attractive regional target for economic CO{sub 2} storage and enhanced natural gas production.

  20. ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

    SciTech Connect (OSTI)

    Brandon C. Nuttall

    2005-07-29T23:59:59.000Z

    Devonian gas shales underlie approximately two-thirds of Kentucky. In the shale, natural gas is adsorbed on clay and kerogen surfaces. This is analogous to methane storage in coal beds, where CO{sub 2} is preferentially adsorbed, displacing methane. Black shales may similarly desorb methane in the presence of CO{sub 2}. Drill cuttings from the Kentucky Geological Survey Well Sample and Core Library were sampled to determine CO{sub 2} and CH{sub 4} adsorption isotherms. Sidewall core samples were acquired to investigate CO{sub 2} displacement of methane. An elemental capture spectroscopy log was acquired to investigate possible correlations between adsorption capacity and mineralogy. Average random vitrinite reflectance data range from 0.78 to 1.59 (upper oil to wet gas and condensate hydrocarbon maturity range). Total organic content determined from acid-washed samples ranges from 0.69 to 14 percent. CO{sub 2} adsorption capacities at 400 psi range from a low of 14 scf/ton in less organic-rich zones to more than 136 scf/ton. There is a direct correlation between measured total organic carbon content and the adsorptive capacity of the shale; CO{sub 2} adsorption capacity increases with increasing organic carbon content. Initial estimates based on these data indicate a sequestration capacity of 5.3 billion tons of CO{sub 2} in the Lower Huron Member of the Ohio Shale of eastern Kentucky and as much as 28 billion tons total in the deeper and thicker parts of the Devonian shales in Kentucky. Should the black shales of Kentucky prove to be a viable geologic sink for CO{sub 2}, their extensive occurrence in Paleozoic basins across North America would make them an attractive regional target for economic CO{sub 2} storage and enhanced natural gas production.

  1. ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

    SciTech Connect (OSTI)

    Brandon C. Nuttall

    2005-01-28T23:59:59.000Z

    Devonian gas shales underlie approximately two-thirds of Kentucky. In the shale, natural gas is adsorbed on clay and kerogen surfaces. This is analogous to methane storage in coal beds, where CO{sub 2} is preferentially adsorbed, displacing methane. Black shales may similarly desorb methane in the presence of CO{sub 2}. Drill cuttings from the Kentucky Geological Survey Well Sample and Core Library were sampled to determine CO{sub 2} and CH{sub 4} adsorption isotherms. Sidewall core samples were acquired to investigate CO{sub 2} displacement of methane. An elemental capture spectroscopy log was acquired to investigate possible correlations between adsorption capacity and mineralogy. Average random vitrinite reflectance data range from 0.78 to 1.59 (upper oil to wet gas and condensate hydrocarbon maturity range). Total organic content determined from acid-washed samples ranges from 0.69 to 14 percent. CO{sub 2} adsorption capacities at 400 psi range from a low of 14 scf/ton in less organic-rich zones to more than 136 scf/ton. There is a direct correlation between measured total organic carbon content and the adsorptive capacity of the shale; CO{sub 2} adsorption capacity increases with increasing organic carbon content. Initial estimates based on these data indicate a sequestration capacity of 5.3 billion tons of CO{sub 2} in the Lower Huron Member of the Ohio Shale of eastern Kentucky and as much as 28 billion tons total in the deeper and thicker parts of the Devonian shales in Kentucky. Should the black shales of Kentucky prove to be a viable geologic sink for CO{sub 2}, their extensive occurrence in Paleozoic basins across North America would make them an attractive regional target for economic CO{sub 2} storage and enhanced natural gas production.

  2. Chemical Bonding and Structural Information of Black CarbonReference Materials and Individual Carbonaceous AtmosphericAerosols

    SciTech Connect (OSTI)

    Hopkins, Rebecca J.; Tivanski, Alexei V.; Marten, Bryan D.; Gilles, Mary K.

    2007-04-25T23:59:59.000Z

    The carbon-to-oxygen ratios and graphitic nature of a rangeof black carbon standard reference materials (BC SRMs), high molecularmass humic-like substances (HULIS) and atmospheric particles are examinedusing scanning transmission X-ray microscopy (STXM) coupled with nearedge X-ray absorption fine structure (NEXAFS) spectroscopy. UsingSTXM/NEXAFS, individual particles with diameter>100 nm are studied,thus the diversity of atmospheric particles collected during a variety offield missions is assessed. Applying a semi-quantitative peak fittingmethod to the NEXAFS spectra enables a comparison of BC SRMs and HULIS toparticles originating from anthropogenic combustion and biomass burns,thus allowing determination of the suitability of these materials forrepresenting atmospheric particles. Anthropogenic combustion and biomassburn particles can be distinguished from one another using both chemicalbonding and structural ordering information. While anthropogeniccombustion particles are characterized by a high proportion ofaromatic-C, the presence of benzoquinone and are highly structurallyordered, biomass burn particles exhibit lower structural ordering, asmaller proportion of aromatic-C and contain a much higher proportion ofoxygenated functional groups.

  3. The radio luminosity, black hole mass and Eddington ratio for quasars from the Sloan Digital Sky Survey

    E-Print Network [OSTI]

    Wei-Hao. Bian; Yan-Mei. Chen; Chen. Hu; Kai. Huang; Yan. Xu

    2008-03-24T23:59:59.000Z

    We investigate the $\\mbh- \\sigma_*$ relation for radio-loud quasars with redshift $zradio luminosity, including 306 radio-loud quasars, 3466 radio-quiet quasars with measured radio luminosity or upper-limit of radio luminosity (181 radio-quiet quasars with measured radio luminosity). The virial supermassive black hole mass (\\mbh) is calculated from the broad \\hb line, the host stellar velocity dispersion ($\\sigma_*$) is traced by the core \\oiii gaseous velocity dispersion, and the radio luminosity and the radio loudness are derived from the FIRST catalog. Our results are follows: (1) For radio-quiet quasars, we confirm that there is no obvious deviation from the $\\mbh- \\sigma_*$ relation defined in inactive galaxies when \\mbh uncertainties and luminosity bias are concerned. (2) We find that radio-loud quasars deviate much from the $\\mbh- \\sigma_*$ relation respect to that for radio-quiet quasars. This deviation is only partly due to the possible cosmology evolution of the $\\mbh- \\sigma_*$ relation and the luminosity bias. (3) The radio luminosity is proportional to $\\mbh^{1.28^{+0.23}_{-0.16}}(\\lb/\\ledd)^{1.29^{+0.31}_{-0.24}}$ for radio-quiet quasars and $\\mbh^{3.10^{+0.60}_{-0.70}}(\\lb/\\ledd)^{4.18^{+1.40}_{-1.10}}$ for radio-loud quasars. The weaker correlation of the radio luminosity dependence upon the mass and the Eddington ratio for radio-loud quasars shows that other physical effects would account for their radio luminosities, such as the black hole spin.

  4. Recoil velocities from equal-mass binary black-hole mergers: A systematic investigation of spin-orbit aligned configurations

    SciTech Connect (OSTI)

    Pollney, Denis; Reisswig, Christian; Szilagyi, Bela; Ansorg, Marcus; Dorband, Ernst Nils; Koppitz, Michael [Max-Planck-Institut fuer Gravitationsphysik, Albert-Einstein-Institut, Potsdam-Golm (Germany); Rezzolla, Luciano [Max-Planck-Institut fuer Gravitationsphysik, Albert-Einstein-Institut, Potsdam-Golm (Germany); Department of Physics and Astronomy, Louisiana State University, Baton Rouge, Louisiana (United States); Deris, Barrett [Center for Computation and Technology, Louisiana State University, Baton Rouge, Louisiana (United States); Department of Physics, University of California at San Diego, La Jolla, California (United States); Diener, Peter; Schnetter, Erik [Department of Physics and Astronomy, Louisiana State University, Baton Rouge, Louisiana (United States); Center for Computation and Technology, Louisiana State University, Baton Rouge, Louisiana (United States); Nagar, Alessandro [Dipartimento di Fisica, Politecnico di Torino and INFN, sez. di Torino (Italy)

    2007-12-15T23:59:59.000Z

    Binary black-hole systems with spins aligned with the orbital angular momentum are of special interest, as studies indicate that this configuration is preferred in nature due to non-vacuum environmental interactions, as well as post-Newtonian (PN) spin-orbit couplings. If the spins of the two bodies differ, there can be a prominent beaming of the gravitational radiation during the late plunge, causing a recoil of the final merged black hole. In this paper we perform an accurate and systematic study of recoil velocities from a sequence of equal-mass black holes whose spins are aligned with the orbital angular momentum, and whose individual spins range from a=+0.584 to -0.584. In this way we extend and refine the results of a previous study which concentrated on the antialigned portion of this sequence, to arrive at a consistent maximum recoil of 448{+-}5 km/s for antialigned models as well as to a phenomenological expression for the recoil velocity as a function of spin ratio. Quite surprisingly, this relation highlights a nonlinear behavior, not predicted by the PN estimates, and can be readily employed in astrophysical studies on the evolution of binary black holes in massive galaxies. An essential result of our analysis, without which no systematic behavior can be found, is the identification of different stages in the waveform, including a transient due to lack of an initial linear momentum in the initial data. Furthermore, by decomposing the recoil computation into coupled modes, we are able to identify a pair of terms which are largely responsible for the kick, indicating that an accurate computation can be obtained from modes up to l=3. Finally, we provide accurate measures of the radiated energy and angular momentum, finding these to increase linearly with the spin ratio, and derive simple expressions for the final spin and the radiated angular momentum which can be easily implemented in N-body simulations of compact stellar systems. Our code is calibrated with strict convergence tests and we verify the correctness of our measurements by using multiple independent methods whenever possible.

  5. Analytical Validation of Accelerator Mass Spectrometry for Pharmaceutical Development: the Measurement of Carbon-14 Isotope Ratio.

    SciTech Connect (OSTI)

    Keck, B D; Ognibene, T; Vogel, J S

    2010-02-05T23:59:59.000Z

    Accelerator mass spectrometry (AMS) is an isotope based measurement technology that utilizes carbon-14 labeled compounds in the pharmaceutical development process to measure compounds at very low concentrations, empowers microdosing as an investigational tool, and extends the utility of {sup 14}C labeled compounds to dramatically lower levels. It is a form of isotope ratio mass spectrometry that can provide either measurements of total compound equivalents or, when coupled to separation technology such as chromatography, quantitation of specific compounds. The properties of AMS as a measurement technique are investigated here, and the parameters of method validation are shown. AMS, independent of any separation technique to which it may be coupled, is shown to be accurate, linear, precise, and robust. As the sensitivity and universality of AMS is constantly being explored and expanded, this work underpins many areas of pharmaceutical development including drug metabolism as well as absorption, distribution and excretion of pharmaceutical compounds as a fundamental step in drug development. The validation parameters for pharmaceutical analyses were examined for the accelerator mass spectrometry measurement of {sup 14}C/C ratio, independent of chemical separation procedures. The isotope ratio measurement was specific (owing to the {sup 14}C label), stable across samples storage conditions for at least one year, linear over 4 orders of magnitude with an analytical range from one tenth Modern to at least 2000 Modern (instrument specific). Further, accuracy was excellent between 1 and 3 percent while precision expressed as coefficient of variation is between 1 and 6% determined primarily by radiocarbon content and the time spent analyzing a sample. Sensitivity, expressed as LOD and LLOQ was 1 and 10 attomoles of carbon-14 (which can be expressed as compound equivalents) and for a typical small molecule labeled at 10% incorporated with {sup 14}C corresponds to 30 fg equivalents. AMS provides an sensitive, accurate and precise method of measuring drug compounds in biological matrices.

  6. Optical Properties of Mixed Black Carbon, Inorganic and Secondary Organic Aerosols

    SciTech Connect (OSTI)

    Paulson, S E

    2012-05-30T23:59:59.000Z

    Summarizes the achievements of the project, which are divided into four areas: 1) Optical properties of secondary organic aerosols; 2) Development and of a polar nephelometer to measure aerosol optical properties and theoretical approaches to several optical analysis problems, 3) Studies on the accuracy of measurements of absorbing carbon by several methods, and 4) Environmental impacts of biodiesel.

  7. Do radio-loud AGN really follow the same relation between black hole mass and stellar velocity dispersion as normal galaxies?

    E-Print Network [OSTI]

    Liu Yi; D. R. Jiang

    2006-12-11T23:59:59.000Z

    In an examination of the relationship between the black hole mass and stellar velocity dispersion in radio-loud active galactic nuclei (AGNs), we studied two effects which may cause uncertainties in the black hole mass estimates of radio-loud AGNs: the relativistic beaming effect on the observed optical continuum radiation and the orientation effect on the broad emission line width. After correcting these two effects, we re-examined the relation between black hole mass and stellar velocity dispersion which derived from [OIII] line width for a sample of radio-loud and radio-quiet AGNs, and found the relation for radio-loud AGNs still deviated from that for nearby normal galaxies and radio-quiet AGNs. We also found there is no significant correlation between radio jet power and narrow [OIII] line width, indicating absence of strong interaction between radio jet and narrow line region. It may be that the deviation of the relation between black hole mass and stellar velocity dispersion of radio-loud AGNs is intrinsic, or that the [OIII] line width is not a good indicator of stellar velocity dispersion for radio-loud AGNs.

  8. Mass spectrum of primordial black holes from inflationary perturbation in the Randall-Sundrum braneworld: a limit on blue spectra

    E-Print Network [OSTI]

    Yuuiti Sendouda; Shigehiro Nagataki; Katsuhiko Sato

    2006-06-07T23:59:59.000Z

    The mass spectrum of the primordial black holes formed by density perturbation in the radiation-dominated era of the Randall-Sundrum type-2 cosmology is given. The spectrum coincides with standard four-dimensional one on large scales but the deviation is apparent on smaller scales. The mass spectrum is initially softer than standard four-dimensional one, while after accretion during the earliest era it becomes harder than that. We also show expected extragalactic diffuse photon background spectra varying the initial perturbation power-law power spectrum and give constraints on the blue spectra and/or the reheating temperature. The most recent observations on the small scale density perturbation from WMAP, SDSS and Lyman-\\alpha Forest are used. What we get are interpreted as constraints on the smaller scale inflation on the brane connected to the larger one at the scale of Lyman-\\alpha Forest. If we set the bulk curvature radius to be 0.1 mm and assume the reheating temperature is higher than 10^6 GeV, the scalar spectral index from the smaller scale inflation is constrained to be n \\lesssim 1.3. Typically, the constraints are tighter than standard four-dimensional one, which is also revised by us using the most recent observations.

  9. A NEW CLASS OF GAMMA-RAY BURSTS FROM STELLAR DISRUPTIONS BY INTERMEDIATE-MASS BLACK HOLES

    SciTech Connect (OSTI)

    Gao, H.; Lu, Y.; Zhang, S. N. [National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China)

    2010-07-01T23:59:59.000Z

    It has been argued that the long gamma-ray burst (GRB) of GRB 060614 without an associated supernova (SN) has challenged the current classification and fuel model for long GRBs, and thus a tidal disruption model has been proposed to account for such an event. Since it is difficult to detect SNe for long GRBs at high redshift, the absence of an SN association cannot be regarded as the solid criterion for a new classification of long GRBs similar to GRB 060614, called GRB 060614-type bursts. Fortunately, we now know that there is an obvious periodic substructure observed in the prompt light curve of GRB 060614. We thus use such periodic substructure as a potential criterion to categorize some long GRBs into a new class of bursts, which might have been fueled by an intermediate-mass black hole (IMBH) gulping a star, rather than a massive star collapsing to form a black hole. Therefore, the second criterion to recognize for this new class of bursts is whether they fit the tidal disruption model. From a total of 328 Swift GRBs with accurately measured durations and without SN association, we find 25 GRBs satisfying the criteria for GRB 060614-type bursts: seven of them are with known redshifts and 18 with unknown redshifts. These new bursts are {approx}6% of the total Swift GRBs, which are clustered into two subclasses: Type I and Type II with considerably different viscous parameters of accretion disks formed by tidally disrupting their different progenitor stars. We suggest that the two different kinds of progenitors are solar-type stars and white dwarfs: the progenitors for four Type I bursts with viscous parameter of around 0.1 are solar-type stars, and the progenitors for 21 Type II bursts with viscous parameter of around 0.3 are white dwarfs. The potential applications of this new class of GRBs as cosmic standard candles are discussed briefly.

  10. SDSS J013127.34-032100.1: a candidate blazar with a 11 billion solar mass black hole at $z$=5.18

    E-Print Network [OSTI]

    Ghisellini, G; Sbarrato, T; Gehrels, N

    2015-01-01T23:59:59.000Z

    The radio-loud quasar SDSS J013127.34-032100.1 at a redshift z=5.18 is one of the most distant radio-loud objects. The radio to optical flux ratio (i.e. the radio-loudness) of the source is large, making it a promising blazar candidate. Its overall spectral energy distribution, completed by the X-ray flux and slope derived through Target of Opportunity Swift/XRT observations, is interpreted by a jet non-thermal plus an accretion disc and molecular torus model. We estimate that its black hole mass is (1.1+-0.2)e10 Msun, the largest found at these redshifts. We derive a viewing angle between 3 and 5 degrees. This implies that there must be other (hundreds) sources with the same black hole mass of SDSS J013127.34-032100.1, but whose jets are pointing away from Earth. We discuss the problems posed by the existence of such large black hole masses at such redshifts, especially in jetted quasars. In fact, if they are associated to rapidly spinning black holes, the accretion efficiency is high, implying a slower pace...

  11. Estimating global black carbon emissions using a top-down Kalman Filter approach*

    E-Print Network [OSTI]

    on the Science and Policy of Global Change combines cutting-edge scientific research with independent policy based on categorized emitting sources and emission factors used to convert burning mass to emissions/yr, a factor of more than 2 higher than commonly used global BC emissions data sets. We further perform 22

  12. Simulating Black Carbon and Dust and their Radiative Forcing in Seasonal Snow: A Case Study over North China with Field Campaign Measurements

    SciTech Connect (OSTI)

    Zhao, Chun; Hu, Zhiyuan; Qian, Yun; Leung, Lai-Yung R.; Huang, J.; Huang, Maoyi; Jin, Jiming; Flanner, M. G.; Zhang, Rudong; Wang, Hailong; Yan, Huiping; Lu, Zifeng; Streets, D. G.

    2014-10-30T23:59:59.000Z

    A state-of-the-art regional model, WRF-Chem, is coupled with the SNICAR model that includes the sophisticated representation of snow metamorphism processes available for climate study. The coupled model is used to simulate the black carbon (BC) and dust concentrations and their radiative forcing in seasonal snow over North China in January-February of 2010, with extensive field measurements used to evaluate the model performance. In general, the model simulated spatial variability of BC and dust mass concentrations in the top snow layer (hereafter BCS and DSTS, respectively) are quantitatively or qualitatively consistent with observations. The model generally moderately underestimates BCS in the clean regions but significantly overestimates BCS in some polluted regions. Most model results fall into the uncertainty ranges of observations. The simulated BCS and DSTS are highest with >5000 ng g-1 and up to 5 mg g-1, respectively, over the source regions and reduce to <50 ng g-1 and <1 ?g g-1, respectively, in the remote regions. BCS and DSTS introduce similar magnitude of radiative warming (~10 W m-2) in snowpack, which is comparable to the magnitude of surface radiative cooling due to BC and dust in the atmosphere. This study represents the first effort in using a regional modeling framework to simulate BC and dust and their direct radiative forcing in snow. Although a variety of observational datasets have been used to attribute model biases, some uncertainties in the results remain, which highlights the need for more observations, particularly concurrent measurements of atmospheric and snow aerosols and the deposition fluxes of aerosols, in future campaigns.

  13. Modelled Black Carbon Radiative Forcing and Atmospheric Lifetime in AeroCom Phase II Constrained by Aircraft Observations

    SciTech Connect (OSTI)

    Samset, B. H.; Myhre, G.; Herber, Andreas; Kondo, Yutaka; Li, Shao-Meng; Moteki, N.; Koike, Makoto; Oshima, N.; Schwarz, Joshua P.; Balkanski, Y.; Bauer, S.; Bellouin, N.; Berntsen, T.; Bian, Huisheng; Chin, M.; Diehl, Thomas; Easter, Richard C.; Ghan, Steven J.; Iversen, T.; Kirkevag, A.; Lamarque, Jean-Francois; Lin, Guang; Liu, Xiaohong; Penner, Joyce E.; Schulz, M.; Seland, O.; Skeie, R. B.; Stier, P.; Takemura, T.; Tsigaridis, Kostas; Zhang, Kai

    2014-11-27T23:59:59.000Z

    Black carbon (BC) aerosols absorb solar radiation, and are generally held to exacerbate global warming through exerting a positive radiative forcing1. However, the total contribution of BC to the ongoing changes in global climate is presently under debate2-8. Both anthropogenic BC emissions and the resulting spatial and temporal distribution of BC concentration are highly uncertain2,9. In particular, long range transport and processes affecting BC atmospheric lifetime are poorly understood, leading to large estimated uncertainty in BC concentration at high altitudes and far from emission sources10. These uncertainties limit our ability to quantify both the historical, present and future anthropogenic climate impact of BC. Here we compare vertical profiles of BC concentration from four recent aircraft measurement campaigns with 13 state of the art aerosol models, and show that recent assessments may have overestimated present day BC radiative forcing. Further, an atmospheric lifetime of BC of less than 5 days is shown to be essential for reproducing observations in transport dominated remote regions. Adjusting model results to measurements in remote regions, and at high altitudes, leads to a 25% reduction in the multi-model median direct BC forcing from fossil fuel and biofuel burning over the industrial era.

  14. A Sensitivity Study on Modeling Black Carbon in Snow and its Radiative Forcing over the Arctic and Northern China

    SciTech Connect (OSTI)

    Qian, Yun; Wang, Hailong; Zhang, Rudong; Flanner, M. G.; Rasch, Philip J.

    2014-06-02T23:59:59.000Z

    Black carbon in snow (BCS) simulated in the Community Atmosphere Model (CAM5) is evaluated against measurements over Northern China and the Arctic, and its sensitivity to atmospheric deposition and two parameters that affect post-depositional enrichment is explored. The BCS concentration is overestimated (underestimated) by a factor of two in Northern China (Arctic) in the default model, but agreement with observations is good over both regions in the simulation with improvements in BC transport and deposition. Sensitivity studies indicate that uncertainty in the melt-water scavenging efficiency (MSE) parameter substantially affects BCS and its radiative forcing (by a factor of 2-7) in the Arctic through post-depositional enrichment. The MSE parameter has a relatively small effect on the magnitude of BCS seasonal cycle but can alter its phase in Northern China. The impact of the snow aging scaling factor (SAF) on BCS, partly through the post-depositional enrichment effect, shows more complex latitudinal and seasonal dependence. Similar to MSE, SAF affects more significantly the magnitude (phase) of BCS season cycle over the Arctic (Northern China). While uncertainty associated with the representation of BC transport and deposition processes in CAM5 is more important than that associated with the two snow model parameters in Northern China, the two uncertainties have comparable effect in the Arctic.

  15. Multiwavelength Monitoring of the Dwarf Seyfert 1 Galaxy NGC 4395. I. A Reverberation-Based Measurement of the Black Hole Mass

    E-Print Network [OSTI]

    Bradley M. Peterson; Misty C. Bentz; Louis-Benoit Desroches; Alexei V. Filippenko; Luis C. Ho; Shai Kaspi; Ari Laor; Dan Maoz; Edward C. Moran; Richard W. Pogge; Alice C. Quillen

    2005-12-15T23:59:59.000Z

    A reverberation-mapping program on NGC 4395, the least-luminous known Seyfert 1 galaxy, undertaken with the Space Telescope Imaging Spectrograph on the Hubble Space Telescope, yields a measurement of the mass of the central black hole of 360,000 solar masses. The observations consist of two visits of 5 orbits each, in 2004 April and July. During each of these visits, the UV continuum varied by at least 10% (rms) and only C IV 1549 showed corresponding variations large enough to reliably determine the emission-line lag, which was measured to be of order one hour for both visits. The size of the C IV-emitting region is about a factor of three smaller than expected if the slope of the broad-line region radius-luminosity relationship is identical to that for the H-beta emission line. NGC 4395 is underluminous even for its small black hole mass; the Eddington ratio of 0.0012 is lower than that of any other active galactic nucleus for which a black hole mass measurement has been made by emission-line reverberation.

  16. High-resolution magnetohydrodynamics simulation of black hole-neutron star merger: Mass ejection and short gamma-ray burst

    E-Print Network [OSTI]

    Kiuchi, Kenta; Kyutoku, Koutarou; Shibata, Masaru; Taniguchi, Keisuke; Wada, Tomohide

    2015-01-01T23:59:59.000Z

    We report results of a high-resolution numerical-relativity simulation for the merger of black hole-magnetized neutron star binaries on Japanese supercomputer "K". We focus on a binary that is subject to tidal disruption and subsequent formation of a massive accretion torus. We find the launch of thermally driven torus wind, subsequent formation of a funnel wall above the torus and a magnetosphere with collimated poloidal magnetic field, and high Blandford-Znajek luminosity. We show for the first time this picture in a self-consistent simulation. The turbulence-like motion induced by the non-axisymmetric magnetorotational instability as well as the Kelvin-Helmholtz instability inside the accretion torus works as an agent to drive the mass accretion and converts the accretion energy to thermal energy, which results in the generation of a strong wind. By an in-depth resolution study, we reveal that high resolution is essential to draw such a picture. We also discuss the implication for the r-process nucleosynth...

  17. Measuring the luminosity and virial black hole mass dependence of quasar-galaxy clustering at z ~ 0.8

    E-Print Network [OSTI]

    Krolewski, Alex G

    2015-01-01T23:59:59.000Z

    We study the dependence of quasar clustering on quasar luminosity and black hole mass by measuring the angular overdensity of photometrically selected galaxies imaged by WISE about z $\\sim$ 0.8 quasars from SDSS. By measuring the quasar-galaxy cross-correlation function and using photometrically selected galaxies, we achieve a higher density of tracer objects and a more sensitive detection of clustering than measurements of the quasar autocorrelation function. We test models of quasar formation and evolution by measuring the luminosity dependence of clustering amplitude. We find a significant overdensity of WISE galaxies about z $\\sim$ 0.8 quasars at 0.2--6.4 h$^{-1}$ Mpc in projected comoving separation. We find no appreciable increase in clustering amplitude with quasar luminosity across a decade in luminosity, and a power-law fit between luminosity and clustering amplitude gives an exponent of $-$0.01 $\\pm$ 0.06 (1 $\\sigma$ errorbar). We also fail to find a significant relationship between clustering ampli...

  18. The Formation of the First Low-Mass Stars From Gas With Low Carbon and Oxygen Abundances

    E-Print Network [OSTI]

    Bromm, V; Bromm, Volker; Loeb, Abraham

    2003-01-01T23:59:59.000Z

    The first stars in the Universe are predicted to have been much more massive than the Sun. Gravitational condensation accompanied by cooling of the primordial gas due to molecular hydrogen, yields a minimum fragmentation scale of a few hundred solar masses. Numerical simulations indicate that once a gas clump acquires this mass, it undergoes a slow, quasi-hydrostatic contraction without further fragmentation. Here we show that as soon as the primordial gas - left over from the Big Bang - is enriched by supernovae to a carbon or oxygen abundance as small as ~0.01-0.1% of that found in the Sun, cooling by singly-ionized carbon or neutral oxygen can lead to the formation of low-mass stars. This mechanism naturally accommodates the discovery of solar mass stars with unusually low (10^{-5.3} of the solar value) iron abundance but with a high (10^{-1.3} solar) carbon abundance. The minimum stellar mass at early epochs is partially regulated by the temperature of the cosmic microwave background. The derived critical...

  19. The Formation of the First Low-Mass Stars From Gas With Low Carbon and Oxygen Abundances

    E-Print Network [OSTI]

    Volker Bromm; Abraham Loeb

    2003-10-21T23:59:59.000Z

    The first stars in the Universe are predicted to have been much more massive than the Sun. Gravitational condensation accompanied by cooling of the primordial gas due to molecular hydrogen, yields a minimum fragmentation scale of a few hundred solar masses. Numerical simulations indicate that once a gas clump acquires this mass, it undergoes a slow, quasi-hydrostatic contraction without further fragmentation. Here we show that as soon as the primordial gas - left over from the Big Bang - is enriched by supernovae to a carbon or oxygen abundance as small as ~0.01-0.1% of that found in the Sun, cooling by singly-ionized carbon or neutral oxygen can lead to the formation of low-mass stars. This mechanism naturally accommodates the discovery of solar mass stars with unusually low (10^{-5.3} of the solar value) iron abundance but with a high (10^{-1.3} solar) carbon abundance. The minimum stellar mass at early epochs is partially regulated by the temperature of the cosmic microwave background. The derived critical abundances can be used to identify those metal-poor stars in our Milky Way galaxy with elemental patterns imprinted by the first supernovae.

  20. 4/25/11 12:25 PMRedOrbit NEWS | Scientists Tracking Black Carbon In The Arctic Page 1 of 3http://www.redorbit.com/modules/news/tools.php?tool=print&id=2033713

    E-Print Network [OSTI]

    Rigor, Ignatius G.

    carbon, has on the rapidly changing Arctic climate. Although the Arctic is typically viewed as a vast an impact on the world's climate for years to come. Black carbon is produced by vehicle engines, aircraft back into the atmosphere," explained Bates. Scientists from The United States, Norway, Russia, Germany

  1. Search for gravitational radiation from intermediate mass black hole binaries in data from the second LIGO-Virgo joint science run

    E-Print Network [OSTI]

    Aasi, J; Abbott, R; Abbott, T; Abernathy, M R; Accadia, T; Acernese, F; Ackley, K; Adams, C; Adams, T; Addesso, P; Adhikari, R X; Affeldt, C; Agathos, M; Aggarwal, N; Aguiar, O D; Ain, A; Ajith, P; Alemic, A; Allen, B; Allocca, A; Amariutei, D; Andersen, M; Anderson, R; Anderson, S B; Anderson, W G; Arai, K; Araya, M C; Arceneaux, C; Areeda, J; Aston, S M; Astone, P; Aufmuth, P; Aulbert, C; Austin, L; Aylott, B E; Babak, S; Baker, P T; Ballardin, G; Ballmer, S W; Barayoga, J C; Barbet, M; Barish, B C; Barker, D; Barone, F; Barr, B; Barsotti, L; Barsuglia, M; Barton, M A; Bartos, I; Bassiri, R; Basti, A; Batch, J C; Bauchrowitz, J; Bauer, Th S; Bavigadda, V; Behnke, B; Bejger, M; Beker, M G; Belczynski, C; Bell, A S; Bell, C; Bergmann, G; Bersanetti, D; Bertolini, A; Betzwieser, J; Beyersdorf, P T; Bilenko, I A; Billingsley, G; Birch, J; Biscans, S; Bitossi, M; Bizouard, M A; Black, E; Blackburn, J K; Blackburn, L; Blair, D; Bloemen, S; Blom, M; Bock, O; Bodiya, T P; Boer, M; Bogaert, G; Bogan, C; Bond, C; Bondu, F; Bonelli, L; Bonnand, R; Bork, R; Born, M; Boschi, V; Bose, Sukanta; Bosi, L; Bradaschia, C; Brady, P R; Braginsky, V B; Branchesi, M; Brau, J E; Briant, T; Bridges, D O; Brillet, A; Brinkmann, M; Brisson, V; Brooks, A F; Brown, D A; Brown, D D; Brückner, F; Buchman, S; Bulik, T; Bulten, H J; Buonanno, A; Burman, R; Buskulic, D; Buy, C; Cadonati, L; Cagnoli, G; Bustillo, J Calderón; Calloni, E; Camp, J B; Campsie, P; Cannon, K C; Canuel, B; Cao, J; Capano, C D; Carbognani, F; Carbone, L; Caride, S; Castiglia, A; Caudill, S; Cavagliŕ, M; Cavalier, F; Cavalieri, R; Celerier, C; Cella, G; Cepeda, C; Cesarini, E; Chakraborty, R; Chalermsongsak, T; Chamberlin, S J; Chao, S; Charlton, P; Chassande-Mottin, E; Chen, X; Chen, Y; Chincarini, A; Chiummo, A; Cho, H S; Chow, J; Christensen, N; Chu, Q; Chua, S S Y; Chung, S; Ciani, G; Clara, F; Clark, J A; Cleva, F; Coccia, E; Cohadon, P -F; Colla, A; Collette, C; Colombini, M; Cominsky, L; Constancio, M; Conte, A; Cook, D; Corbitt, T R; Cordier, M; Cornish, N; Corpuz, A; Corsi, A; Costa, C A; Coughlin, M W; Coughlin, S; Coulon, J -P; Countryman, S; Couvares, P; Coward, D M; Cowart, M; Coyne, D C; Coyne, R; Craig, K; Creighton, J D E; Crowder, S G; Cumming, A; Cunningham, L; Cuoco, E; Dahl, K; Canton, T Dal; Damjanic, M; Danilishin, S L; D'Antonio, S; Danzmann, K; Dattilo, V; Daveloza, H; Davier, M; Davies, G S; Daw, E J; Day, R; Dayanga, T; Debreczeni, G; Degallaix, J; Deléglise, S; Del Pozzo, W; Denker, T; Dent, T; Dereli, H; Dergachev, V; De Rosa, R; DeRosa, R T; DeSalvo, R; Dhurandhar, S; Díaz, M; Di Fiore, L; Di Lieto, A; Di Palma, I; Di Virgilio, A; Donath, A; Donovan, F; Dooley, K L; Doravari, S; Dossa, S; Douglas, R; Downes, T P; Drago, M; Drever, R W P; Driggers, J C; Du, Z; Ducrot, M; Dwyer, S; Eberle, T; Edo, T; Edwards, M; Effler, A; Eggenstein, H; Ehrens, P; Eichholz, J; Eikenberry, S S; Endr?czi, G; Essick, R; Etzel, T; Evans, M; Evans, T; Factourovich, M; Fafone, V; Fairhurst, S; Fang, Q; Farinon, S; Farr, B; Farr, W M; Favata, M; Fehrmann, H; Fejer, M M; Feldbaum, D; Feroz, F; Ferrante, I; Ferrini, F; Fidecaro, F; Finn, L S; Fiori, I; Fisher, R P; Flaminio, R; Fournier, J -D; Franco, S; Frasca, S; Frasconi, F; Frede, M; Frei, Z; Freise, A; Frey, R; Fricke, T T; Fritschel, P; Frolov, V V; Fulda, P; Fyffe, M; Gair, J; Gammaitoni, L; Gaonkar, S; Garufi, F; Gehrels, N; Gemme, G; Genin, E; Gennai, A; Ghosh, S; Giaime, J A; Giardina, K D; Giazotto, A; Gill, C; Gleason, J; Goetz, E; Goetz, R; Gondan, L; González, G; Gordon, N; Gorodetsky, M L; Gossan, S; Goßler, S; Gouaty, R; Gräf, C; Graff, P B; Granata, M; Grant, A; Gras, S; Gray, C; Greenhalgh, R J S; Gretarsson, A M; Groot, P; Grote, H; Grover, K; Grunewald, S; Guidi, G M; Guido, C; Gushwa, K; Gustafson, E K; Gustafson, R; Hammer, D; Hammond, G; Hanke, M; Hanks, J; Hanna, C; Hanson, J; Harms, J; Harry, G M; Harry, I W; Harstad, E D; Hart, M; Hartman, M T; Haster, C -J; Haughian, K; Heidmann, A; Heintze, M; Heitmann, H; Hello, P; Hemming, G; Hendry, M; Heng, I S; Heptonstall, A W; Heurs, M; Hewitson, M; Hild, S; Hoak, D; Hodge, K A; Holt, K; Hooper, S; Hopkins, P; Hosken, D J; Hough, J; Howell, E J; Hu, Y; Huerta, E; Hughey, B; Husa, S; Huttner, S H; Huynh, M; Huynh-Dinh, T; Ingram, D R; Inta, R; Isogai, T; Ivanov, A; Iyer, B R; Izumi, K; Jacobson, M; James, E; Jang, H; Jaranowski, P; Ji, Y; Jiménez-Forteza, F; Johnson, W W; Jones, D I; Jones, R; Jonker, R J G; Ju, L; Haris, K; Kalmus, P; Kalogera, V; Kandhasamy, S; Kang, G; Kanner, J B; Karlen, J; Kasprzack, M; Katsavounidis, E; Katzman, W; Kaufer, H; Kawabe, K; Kawazoe, F; Kéfélian, F; Keiser, G M; Keitel, D; Kelley, D B; Kells, W; Khalaidovski, A; Khalili, F Y; Khazanov, E A; Kim, C; Kim, K; Kim, N G; Kim, N; Kim, Y -M; King, E J; King, P J; Kinzel, D L; Kissel, J S; Klimenko, S; Kline, J; Koehlenbeck, S; Kokeyama, K; Kondrashov, V

    2014-01-01T23:59:59.000Z

    This paper reports on an unmodeled, all-sky search for gravitational waves from merging intermediate mass black hole binaries (IMBHB). The search was performed on data from the second joint science run of the LIGO and Virgo detectors (July 2009 - October 2010) and was sensitive to IMBHBs with a range up to $\\sim 200$ Mpc, averaged over the possible sky positions and inclinations of the binaries with respect to the line of sight. No significant candidate was found. Upper limits on the coalescence-rate density of non-spinning IMBHBs with total masses between 100 and $450 \\ \\mbox{M}_{\\odot}$ and mass ratios between $0.25$ and $1\\,$ were placed by combining this analysis with an analogous search performed on data from the first LIGO-Virgo joint science run (November 2005 - October 2007). The most stringent limit was set for systems consisting of two $88 \\ \\mbox{M}_{\\odot}$ black holes and is equal to $0.12 \\ \\mbox{Mpc}^{-3} \\ \\mbox{Myr}^{-1}$ at the $90\\%$ confidence level. This paper also presents the first esti...

  2. Search for gravitational radiation from intermediate mass black hole binaries in data from the second LIGO-Virgo joint science run

    E-Print Network [OSTI]

    The LIGO Scientific Collaboration; the Virgo Collaboration; J. Aasi; B. P. Abbott; R. Abbott; T. Abbott; M. R. Abernathy; T. Accadia; F. Acernese; K. Ackley; C. Adams; T. Adams; P. Addesso; R. X. Adhikari; C. Affeldt; M. Agathos; N. Aggarwal; O. D. Aguiar; A. Ain; P. Ajith; A. Alemic; B. Allen; A. Allocca; D. Amariutei; M. Andersen; R. Anderson; S. B. Anderson; W. G. Anderson; K. Arai; M. C. Araya; C. Arceneaux; J. Areeda; S. M. Aston; P. Astone; P. Aufmuth; C. Aulbert; L. Austin; B. E. Aylott; S. Babak; P. T. Baker; G. Ballardin; S. W. Ballmer; J. C. Barayoga; M. Barbet; B. C. Barish; D. Barker; F. Barone; B. Barr; L. Barsotti; M. Barsuglia; M. A. Barton; I. Bartos; R. Bassiri; A. Basti; J. C. Batch; J. Bauchrowitz; Th. S. Bauer; V. Bavigadda; B. Behnke; M. Bejger; M. G. Beker; C. Belczynski; A. S. Bell; C. Bell; G. Bergmann; D. Bersanetti; A. Bertolini; J. Betzwieser; P. T. Beyersdorf; I. A. Bilenko; G. Billingsley; J. Birch; S. Biscans; M. Bitossi; M. A. Bizouard; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; S. Bloemen; M. Blom; O. Bock; T. P. Bodiya; M. Boer; G. Bogaert; C. Bogan; C. Bond; F. Bondu; L. Bonelli; R. Bonnand; R. Bork; M. Born; V. Boschi; Sukanta Bose; L. Bosi; C. Bradaschia; P. R. Brady; V. B. Braginsky; M. Branchesi; J. E. Brau; T. Briant; D. O. Bridges; A. Brillet; M. Brinkmann; V. Brisson; A. F. Brooks; D. A. Brown; D. D. Brown; F. Brückner; S. Buchman; T. Bulik; H. J. Bulten; A. Buonanno; R. Burman; D. Buskulic; C. Buy; L. Cadonati; G. Cagnoli; J. Calderón Bustillo; E. Calloni; J. B. Camp; P. Campsie; K. C. Cannon; B. Canuel; J. Cao; C. D. Capano; F. Carbognani; L. Carbone; S. Caride; A. Castiglia; S. Caudill; M. Cavagliŕ; F. Cavalier; R. Cavalieri; C. Celerier; G. Cella; C. Cepeda; E. Cesarini; R. Chakraborty; T. Chalermsongsak; S. J. Chamberlin; S. Chao; P. Charlton; E. Chassande-Mottin; X. Chen; Y. Chen; A. Chincarini; A. Chiummo; H. S. Cho; J. Chow; N. Christensen; Q. Chu; S. S. Y. Chua; S. Chung; G. Ciani; F. Clara; J. A. Clark; F. Cleva; E. Coccia; P. -F. Cohadon; A. Colla; C. Collette; M. Colombini; L. Cominsky; M. Constancio Jr.; A. Conte; D. Cook; T. R. Corbitt; M. Cordier; N. Cornish; A. Corpuz; A. Corsi; C. A. Costa; M. W. Coughlin; S. Coughlin; J. -P. Coulon; S. Countryman; P. Couvares; D. M. Coward; M. Cowart; D. C. Coyne; R. Coyne; K. Craig; J. D. E. Creighton; S. G. Crowder; A. Cumming; L. Cunningham; E. Cuoco; K. Dahl; T. Dal Canton; M. Damjanic; S. L. Danilishin; S. D'Antonio; K. Danzmann; V. Dattilo; H. Daveloza; M. Davier; G. S. Davies; E. J. Daw; R. Day; T. Dayanga; G. Debreczeni; J. Degallaix; S. Deléglise; W. Del Pozzo; T. Denker; T. Dent; H. Dereli; V. Dergachev; R. De Rosa; R. T. DeRosa; R. DeSalvo; S. Dhurandhar; M. Díaz; L. Di Fiore; A. Di Lieto; I. Di Palma; A. Di Virgilio; A. Donath; F. Donovan; K. L. Dooley; S. Doravari; S. Dossa; R. Douglas; T. P. Downes; M. Drago; R. W. P. Drever; J. C. Driggers; Z. Du; M. Ducrot; S. Dwyer; T. Eberle; T. Edo; M. Edwards; A. Effler; H. Eggenstein; P. Ehrens; J. Eichholz; S. S. Eikenberry; G. Endr?czi; R. Essick; T. Etzel; M. Evans; T. Evans; M. Factourovich; V. Fafone; S. Fairhurst; Q. Fang; S. Farinon; B. Farr; W. M. Farr; M. Favata; H. Fehrmann; M. M. Fejer; D. Feldbaum; F. Feroz; I. Ferrante; F. Ferrini; F. Fidecaro; L. S. Finn; I. Fiori; R. P. Fisher; R. Flaminio; J. -D. Fournier; S. Franco; S. Frasca; F. Frasconi; M. Frede; Z. Frei; A. Freise; R. Frey; T. T. Fricke; P. Fritschel; V. V. Frolov; P. Fulda; M. Fyffe; J. Gair; L. Gammaitoni; S. Gaonkar; F. Garufi; N. Gehrels; G. Gemme; E. Genin; A. Gennai; S. Ghosh; J. A. Giaime; K. D. Giardina; A. Giazotto; C. Gill; J. Gleason; E. Goetz; R. Goetz; L. Gondan; G. González; N. Gordon; M. L. Gorodetsky; S. Gossan; S. Goßler; R. Gouaty; C. Gräf; P. B. Graff; M. Granata; A. Grant; S. Gras; C. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; P. Groot; H. Grote; K. Grover; S. Grunewald; G. M. Guidi; C. Guido; K. Gushwa; E. K. Gustafson; R. Gustafson; D. Hammer; G. Hammond; M. Hanke; J. Hanks; C. Hanna; J. Hanson; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; M. Hart; M. T. Hartman; C. -J. Haster; K. Haughian; A. Heidmann; M. Heintze; H. Heitmann; P. Hello; G. Hemming; M. Hendry; I. S. Heng; A. W. Heptonstall; M. Heurs; M. Hewitson; S. Hild; D. Hoak; K. A. Hodge; K. Holt; S. Hooper; P. Hopkins; D. J. Hosken; J. Hough; E. J. Howell; Y. Hu; E. Huerta; B. Hughey; S. Husa; S. H. Huttner; M. Huynh; T. Huynh-Dinh; D. R. Ingram; R. Inta; T. Isogai; A. Ivanov; B. R. Iyer; K. Izumi; M. Jacobson; E. James; H. Jang; P. Jaranowski; Y. Ji; F. Jiménez-Forteza; W. W. Johnson; D. I. Jones; R. Jones; R. J. G. Jonker; L. Ju; K Haris; P. Kalmus; V. Kalogera; S. Kandhasamy; G. Kang; J. B. Kanner; J. Karlen; M. Kasprzack; E. Katsavounidis; W. Katzman; H. Kaufer; K. Kawabe; F. Kawazoe; F. Kéfélian; G. M. Keiser; D. Keitel; D. B. Kelley; W. Kells; A. Khalaidovski

    2014-06-19T23:59:59.000Z

    This paper reports on an unmodeled, all-sky search for gravitational waves from merging intermediate mass black hole binaries (IMBHB). The search was performed on data from the second joint science run of the LIGO and Virgo detectors (July 2009 - October 2010) and was sensitive to IMBHBs with a range up to $\\sim 200$ Mpc, averaged over the possible sky positions and inclinations of the binaries with respect to the line of sight. No significant candidate was found. Upper limits on the coalescence-rate density of nonspinning IMBHBs with total masses between 100 and $450 \\ \\mbox{M}_{\\odot}$ and mass ratios between $0.25$ and $1\\,$ were placed by combining this analysis with an analogous search performed on data from the first LIGO-Virgo joint science run (November 2005 - October 2007). The most stringent limit was set for systems consisting of two $88 \\ \\mbox{M}_{\\odot}$ black holes and is equal to $0.12 \\ \\mbox{Mpc}^{-3} \\ \\mbox{Myr}^{-1}$ at the $90\\%$ confidence level. This paper also presents the first estimate, for the case of an unmodeled analysis, of the impact on the search range of IMBHB spin configurations: the visible volume for IMBHBs with nonspinning components is roughly doubled for a population of IMBHBs with spins aligned with the binary's orbital angular momentum and uniformly distributed in the dimensionless spin parameter up to 0.8, whereas an analogous population with antialigned spins decreases the visible volume by $\\sim 20\\%\\,$.

  3. Thermogravimetry-Mass Spectrometry for Carbon Nanotube Detection in Complex Mixtures

    E-Print Network [OSTI]

    Plata, Desiree Louise

    In spite of the growth of the carbon nanotube (CNT) industry, there are no established analytical methods with which to detect or quantify CNTs in environmental matrices. Given that CNTs have relatively high thermal ...

  4. Final spin and radiated energy in numerical simulations of binary black holes with equal masses and equal, aligned or anti-aligned spins

    E-Print Network [OSTI]

    Daniel A. Hemberger; Geoffrey Lovelace; Thomas J. Loredo; Lawrence E. Kidder; Mark A. Scheel; Béla Szilágyi; Nicholas W. Taylor; Saul A. Teukolsky

    2013-09-23T23:59:59.000Z

    The behavior of merging black holes (including the emitted gravitational waves and the properties of the remnant) can currently be computed only by numerical simulations. This paper introduces ten numerical relativity simulations of binary black holes with equal masses and equal spins aligned or anti-aligned with the orbital angular momentum. The initial spin magnitudes have $|\\chi_i| \\lesssim 0.95$ and are more concentrated in the aligned direction because of the greater astrophysical interest of this case. We combine this data with five previously reported simulations of the same configuration, but with different spin magnitudes, including the highest spin simulated to date, $\\chi_i \\approx 0.97$. This data set is sufficiently accurate to enable us to offer improved analytic fitting formulae for the final spin and for the energy radiated by gravitational waves as a function of initial spin. The improved fitting formulae can help to improve our understanding of the properties of binary black hole merger remnants and can be used to enhance future approximate waveforms for gravitational wave searches, such as Effective-One-Body waveforms.

  5. BLACK HOLE-NEUTRON STAR MERGERS WITH A HOT NUCLEAR EQUATION OF STATE: OUTFLOW AND NEUTRINO-COOLED DISK FOR A LOW-MASS, HIGH-SPIN CASE

    SciTech Connect (OSTI)

    Deaton, M. Brett; Duez, Matthew D. [Department of Physics and Astronomy, Washington State University, Pullman, WA 99164 (United States); Foucart, Francois; O'Connor, Evan [Canadian Institute for Theoretical Astrophysics, University of Toronto, Toronto, Ontario M5S 3H8 (Canada); Ott, Christian D.; Scheel, Mark A.; Szilagyi, Bela [TAPIR, MC 350-17, California Institute of Technology, Pasadena, CA 91125 (United States); Kidder, Lawrence E.; Muhlberger, Curran D., E-mail: mbdeaton@wsu.edu, E-mail: m.duez@wsu.edu [Center for Radiophysics and Space Research, Cornell University, Ithaca, NY 14853 (United States)

    2013-10-10T23:59:59.000Z

    Neutrino emission significantly affects the evolution of the accretion tori formed in black hole-neutron star mergers. It removes energy from the disk, alters its composition, and provides a potential power source for a gamma-ray burst. To study these effects, simulations in general relativity with a hot microphysical equation of state (EOS) and neutrino feedback are needed. We present the first such simulation, using a neutrino leakage scheme for cooling to capture the most essential effects and considering a moderate mass (1.4 M{sub ?} neutron star, 5.6 M{sub ?} black hole), high-spin (black hole J/M {sup 2} = 0.9) system with the K{sub 0} = 220 MeV Lattimer-Swesty EOS. We find that about 0.08 M{sub ?} of nuclear matter is ejected from the system, while another 0.3 M{sub ?} forms a hot, compact accretion disk. The primary effects of the escaping neutrinos are (1) to make the disk much denser and more compact, (2) to cause the average electron fraction Y{sub e} of the disk to rise to about 0.2 and then gradually decrease again, and (3) to gradually cool the disk. The disk is initially hot (T ? 6 MeV) and luminous in neutrinos (L{sub ?} ? 10{sup 54} erg s{sup –1}), but the neutrino luminosity decreases by an order of magnitude over 50 ms of post-merger evolution.

  6. Stability and Regeneration of Catalysts for the Destruction of Tars from Bio-mass Black Liquor Gasification

    SciTech Connect (OSTI)

    Pradeep Agrawal

    2004-09-07T23:59:59.000Z

    The goal of this project was to develop catalytic materials and processes that would be effective in the destruction of tars formed during the gasification of black liquor and biomass. We report here the significant results obtained at the conclusion of this two year project.

  7. New methodology for estimating biofuel consumption for cooking: Atmospheric emissions of black carbon and sulfur dioxide from India

    E-Print Network [OSTI]

    Dickerson, Russell R.

    New methodology for estimating biofuel consumption for cooking: Atmospheric emissions of black; accepted 8 June 2004; published 30 July 2004. [1] The dominance of biofuel combustion emissions in the Indian region, and the inherently large uncertainty in biofuel use estimates based on cooking energy

  8. Thermokinetic/mass-transfer analysis of carbon capture for reuse/sequestration.

    SciTech Connect (OSTI)

    Stechel, Ellen Beth; Brady, Patrick Vane; Staiger, Chad Lynn; Luketa, Anay Josephine

    2010-09-01T23:59:59.000Z

    Effective capture of atmospheric carbon is a key bottleneck preventing non bio-based, carbon-neutral production of synthetic liquid hydrocarbon fuels using CO{sub 2} as the carbon feedstock. Here we outline the boundary conditions of atmospheric carbon capture for recycle to liquid hydrocarbon fuels production and re-use options and we also identify the technical advances that must be made for such a process to become technically and commercially viable at scale. While conversion of atmospheric CO{sub 2} into a pure feedstock for hydrocarbon fuels synthesis is presently feasible at the bench-scale - albeit at high cost energetically and economically - the methods and materials needed to concentrate large amounts of CO{sub 2} at low cost and high efficiency remain technically immature. Industrial-scale capture must entail: (1) Processing of large volumes of air through an effective CO{sub 2} capture media and (2) Efficient separation of CO{sub 2} from the processed air flow into a pure stream of CO{sub 2}.

  9. Extending Virial Black Hole Mass Estimates to Low-Luminosity or Obscured AGN: the cases of NGC 4395 and MCG -01-24-012

    E-Print Network [OSTI]

    La Franca, F; Ricci, F; Sani, E; Brusa, M; Maiolino, R; Fiore, F; Marconi, A; Vignali, C

    2015-01-01T23:59:59.000Z

    In the last decade, using single epoch (SE) virial based spectroscopic optical observations, it has been possible to measure the black hole (BH) mass on large type 1 Active Galactic Nuclei (AGN) samples. However this kind of measurements can not be applied on those obscured type 2 and/or low luminosity AGN where the nuclear component does not dominate in the optical. We have derived new SE relationships, based on the FWHM and luminosity of the broad line region component of the Pabeta emission line and/or the hard X-ray luminosity in the 14-195 keV band, which have the prospect of better working with low luminosity or obscured AGN. The SE relationships have been calibrated in the 10^5-10^9 M_sol mass range, using a sample of AGN whose BH masses have been previously measured using reverberation mapping techniques. Our tightest relationship between the reverberation-based BH mass and the SE virial product has an intrinsic spread of 0.20 dex. Thanks to these SE relations, in agreement with previous estimates, we...

  10. Beryllium-7 labeled carbon particles and method of making

    DOE Patents [OSTI]

    Richards, Powell (New Bern, NC); Mausner, Leonard F. (Stony Brook, NY); Prach, Thomas F. (Port Jefferson, NY)

    1987-01-01T23:59:59.000Z

    Beryllium-7 labeled carbon particles made from the proton irradiation of carbon materials, preferably from dry carbon black are disclosed. Such particles are useful as gamma emitting radiotracers.

  11. Beryllium-7 labeled carbon particles and method of making

    DOE Patents [OSTI]

    Richards, P.; Mausner, L.F.; Prach, T.F.

    1985-04-29T23:59:59.000Z

    Beryllium-7 labeled carbon particles made from the proton irradiation of carbon materials, preferably from dry carbon black are disclosed. Such particles are useful as gamma emitting radiotracers.

  12. Beryllium-7 labeled carbon particles and method of making

    DOE Patents [OSTI]

    Richards, P.; Mausner, L.F.; Prach, T.F.

    1987-11-17T23:59:59.000Z

    Beryllium-7 labeled carbon particles made from the proton irradiation of carbon materials, preferably from dry carbon black are disclosed. Such particles are useful as gamma emitting radiotracers.

  13. ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

    SciTech Connect (OSTI)

    Brandon C. Nuttall

    2004-08-01T23:59:59.000Z

    Devonian gas shales underlie approximately two-thirds of Kentucky. In the shale, natural gas is adsorbed on clay and kerogen surfaces. This is analogous to methane storage in coal beds, where CO{sub 2} is preferentially adsorbed, displacing methane. Black shales may similarly desorb methane in the presence of CO{sub 2}. Drill cuttings from the Kentucky Geological Survey Well Sample and Core Library are being sampled to collect CO{sub 2} adsorption isotherms. Sidewall core samples have been acquired to investigate CO{sub 2} displacement of methane. An elemental capture spectroscopy log has been acquired to investigate possible correlations between adsorption capacity and mineralogy. Average random vitrinite reflectance data range from 0.78 to 1.59 (upper oil to wet gas and condensate hydrocarbon maturity range). Total organic content determined from acid-washed samples ranges from 0.69 to 4.62 percent. CO{sub 2} adsorption capacities at 400 psi range from a low of 19 scf/ton in less organic-rich zones to more than 86 scf/ton in the Lower Huron Member of the shale. Initial estimates based on these data indicate a sequestration capacity of 5.3 billion tons of CO{sub 2} in the Lower Huron Member of the Ohio Shale of eastern Kentucky and as much as 28 billion tons total in the deeper and thicker parts of the Devonian shales in Kentucky. Should the black shales of Kentucky prove to be a viable geologic sink for CO{sub 2}, their extensive occurrence in Paleozoic basins across North America would make them an attractive regional target for economic CO{sub 2} storage and enhanced natural gas production.

  14. ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

    SciTech Connect (OSTI)

    Brandon C. Nuttall

    2005-01-01T23:59:59.000Z

    Devonian gas shales underlie approximately two-thirds of Kentucky. In the shale, natural gas is adsorbed on clay and kerogen surfaces. This is analogous to methane storage in coal beds, where CO{sub 2} is preferentially adsorbed, displacing methane. Black shales may similarly desorb methane in the presence of CO{sub 2}. Drill cuttings from the Kentucky Geological Survey Well Sample and Core Library were sampled to determine CO{sub 2} and CH{sub 4} adsorption isotherms. Sidewall core samples were acquired to investigate CO{sub 2} displacement of methane. An elemental capture spectroscopy log was acquired to investigate possible correlations between adsorption capacity and mineralogy. Average random vitrinite reflectance data range from 0.78 to 1.59 (upper oil to wet gas and condensate hydrocarbon maturity range). Total organic content determined from acid-washed samples ranges from 0.69 to 14 percent. CO{sub 2} adsorption capacities at 400 psi range from a low of 14 scf/ton in less organic-rich zones to more than 136 scf/ton. Initial estimates based on these data indicate a sequestration capacity of 5.3 billion tons of CO{sub 2} in the Lower Huron Member of the Ohio Shale of eastern Kentucky and as much as 28 billion tons total in the deeper and thicker parts of the Devonian shales in Kentucky. Should the black shales of Kentucky prove to be a viable geologic sink for CO{sub 2}, their extensive occurrence in Paleozoic basins across North America would make them an attractive regional target for economic CO{sub 2} storage and enhanced natural gas production.

  15. Thermodynamical instability of black holes

    E-Print Network [OSTI]

    V. V. Kiselev

    2012-08-07T23:59:59.000Z

    In contrast to Hawking radiation of black hole with a given spacetime structure, we consider a competitive transition due to a heat transfer from a hotter inner horizon to a colder outer horizon of Kerr black hole, that results in a stable thermodynamical state of extremal black hole. In this process, by supposing an emission of gravitational quanta, we calculate the mass of extremal black hole in the final state of transition.

  16. Observational Evidence for Black Holes

    E-Print Network [OSTI]

    Ramesh Narayan; Jeffrey E. McClintock

    2014-07-20T23:59:59.000Z

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

  17. Black Shales Adina Paytan, Stanford University, USA

    E-Print Network [OSTI]

    Paytan, Adina

    Tales of Black Shales Adina Paytan, Stanford University, USA Several times during the middle of the Cretaceous period, between 125 and 80 million years ago, organic-carbon-rich black shales were deposited over large areas of the ocean floor. These black shales provide valuable information about past climates

  18. Spacetime noncommutative effect on black hole as particle accelerators

    E-Print Network [OSTI]

    Chikun Ding; Changqing Liu; Qian Guo

    2013-01-08T23:59:59.000Z

    We study the spacetime noncommutative effect on black hole as particle accelerators and, find that particle falling from infinity with zero velocity cannot collide with unbound energy when the noncommutative Kerr black hole is exactly extremal. Our results also show that the bigger of the spinning black hole's mass is, the higher of center of mass energy that the particles obtain. For small and medium noncommutative Schwarzschild black hole, the collision energy depends on the black holes' mass.

  19. Effects of volatile coatings on the morphology and optical detection of combustion-generated black carbon particles.

    SciTech Connect (OSTI)

    Bambha, Ray P.; Dansson, Mark Alex; Schrader, Paul E.; Michelsen, Hope A.

    2013-09-01T23:59:59.000Z

    We have measured time-resolved laser-induced incandescence (LII) from combustion-generated mature soot extracted from a burner and (1) coated with oleic acid or (2) coated with oleic acid and then thermally denuded using a thermodenuder. The soot samples were size selected using a differential mobility analyser and characterized with a scanning mobility particle sizer, centrifugal particle mass analyser, and transmission electron microscope. The results demonstrate a strong influence of coatings particle morphology and on the magnitude and temporal evolution of the LII signal. For coated particles higher laser fluences are required to reach LII signal levels comparable to those of uncoated particles. This effect is predominantly attributable to the additional energy needed to vaporize the coating while heating the particle. LII signals are higher and signal decay rates are significantly slower for thermally denuded particles relative to coated or uncoated particles, particularly at low and intermediate laser fluences.

  20. The Role of Circulation Features on Black Carbon Transport into the Arctic in the Community Atmosphere Model Version 5 (CAM5)

    SciTech Connect (OSTI)

    Ma, Po-Lun; Rasch, Philip J.; Wang, Hailong; Zhang, Kai; Easter, Richard C.; Tilmes, S.; Fast, Jerome D.; Liu, Xiaohong; Yoon, Jin-Ho; Lamarque, Jean-Francois

    2013-05-28T23:59:59.000Z

    Current climate models generally under-predict the surface concentration of black carbon (BC) in the Arctic due to the uncertainties associated with emissions, transport, and removal. This bias is also present in the Community Atmosphere Model Version 5.1 (CAM5). In this study, we investigate the uncertainty of Arctic BC due to transport processes simulated by CAM5 by configuring the model to run in an “offline mode” in which the large-scale circulations are prescribed. We compare the simulated BC transport when the offline model is driven by the meteorology predicted by the standard free-running CAM5 with simulations where the meteorology is constrained to agree with reanalysis products. Some circulation biases are apparent: the free-running CAM5 produces about 50% less transient eddy transport of BC than the reanalysis-driven simulations, which may be attributed to the coarse model resolution insufficient to represent eddies. Our analysis shows that the free-running CAM5 reasonably captures the essence of the Arctic Oscillation (AO), but some discernable differences in the spatial pattern of the AO between the free-running CAM5 and the reanalysis-driven simulations result in significantly different AO modulation of BC transport over Northeast Asia and Eastern Europe. Nevertheless, we find that the overall climatological circulation patterns simulated by the free-running CAM5 generally resembles those from the reanalysis products, and BC transport is very similar in both simulation sets. Therefore, the simulated circulation features regulating the long-range BC transport is unlikely the most important cause of the large under-prediction of surface BC concentration in the Arctic.

  1. Do Black Holes Exist?

    E-Print Network [OSTI]

    J. W. Moffat

    1993-02-22T23:59:59.000Z

    The problem of information loss in black hole formation and the associated violations of basic laws of physics, such as conservation of energy, causality and unitarity, are avoided in the nonsymmetric gravitational theory, if the NGT charge of a black hole and its mass satisfy an inequality that does not violate any known experimental data and allows the existence of white dwarfs and neutron stars.

  2. Search for Quantum Black Hole Production in High-Invariant-Mass Lepton + Jet Final States Using pp Collisions at ?s = 8 TeV and the ATLAS Detector

    E-Print Network [OSTI]

    Taylor, Frank E.

    This Letter presents a search for quantum black-hole production using 20.3??fb[superscript ?1] of data collected with the ATLAS detector in pp collisions at the LHC at ?s = 8??TeV. The quantum black holes are assumed to ...

  3. activated carbon application: Topics by E-print Network

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

    black and flexible graphite. C 2004 Kluwer Academic Publishers 1. Introduction Carbon materials (including composite Chung, Deborah D.L. 36 Active Carbon and Oxygen Shell Burning...

  4. Total organic carbon as an indicator of wood delignification

    SciTech Connect (OSTI)

    Genco, J.M.; Hassler, J.C.; Busayasakul, N.

    1984-07-01T23:59:59.000Z

    Kraft pulping experiments were performed in a 12-liter electrically heated laboratory digester to determine pulp yields and residual lignin content (kappa number) as a function of time. Samples of the pulp and the black liquor were analyzed for total organic carbon (TOC) content by oxidizing the samples in a combustion furnace and measuring the released CO/sub 2/ gravimetrically. The experimental data on TOC were correlated with kappa number and yield. Results can be explained satisfactorily using a mathematical model based upon the principle of conservation of mass. The TOC content of black liquor appears to be a useful parameter for batch digester control. 17 references.

  5. A Link To The Future: A Pilot Study Look at How Historically Black Colleges and Universities With Journalism and Mass Communications Units Use The Internet in Recruiting

    E-Print Network [OSTI]

    Crawford II, Jerry L.

    2012-04-01T23:59:59.000Z

    Historically Black Colleges and Universities (HBCUs) have had the ability to recruit African-American students since the 1860s by stressing a sense of inclusion and family through their mission statements and community ...

  6. Charging Black Saturn?

    E-Print Network [OSTI]

    Brenda Chng; Robert Mann; Eugen Radu; Cristian Stelea

    2008-10-28T23:59:59.000Z

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

  7. ARM - Measurement - Black carbon concentration

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadap Documentation TDMADAP : XDC documentationBarrow, AlaskaWhenimage

  8. Black Holes

    E-Print Network [OSTI]

    P. K. Townsend

    1997-07-04T23:59:59.000Z

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

  9. Energy of 4-Dimensional Black Hole, etc

    E-Print Network [OSTI]

    Dmitriy Palatnik

    2011-07-18T23:59:59.000Z

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

  10. Black Hole's 1/N Hair

    E-Print Network [OSTI]

    Gia Dvali; Cesar Gomez

    2012-03-29T23:59:59.000Z

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

  11. Charged spinning black holes as particle accelerators

    SciTech Connect (OSTI)

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

    2010-11-15T23:59:59.000Z

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

  12. 3-D Nano-Structured Carbon/Tin Composite Anodes

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

    uniform dispersion of Sn in the carbon matrix 20 10 * Carbon matrix displays 10-15 nm graphene 0 1 2 3 4 >4 domains and regions typical of carbon blacks P article S ize (nm )...

  13. Black hole accretion discs

    E-Print Network [OSTI]

    Lasota, Jean-Pierre

    2015-01-01T23:59:59.000Z

    This is an introduction to models of accretion discs around black holes. After a presentation of the non-relativistic equations describing the structure and evolution of geometrically thin accretion discs we discuss their steady-state solutions and compare them to observation. Next we describe in detail the thermal-viscous disc instability model and its application to dwarf novae for which it was designed and its X-ray irradiated-disc version which explains the soft X--ray transients, i.e. outbursting black-hole low-mass X-ray binaries. We then turn to the role of advection in accretion flow onto black holes illustrating its action and importance with a toy model describing both ADAFs and slim discs. We conclude with a presentation of the general-relativistic formalism describing accretion discs in the Kerr space-time.

  14. Multipole moments for black objects in five dimensions

    E-Print Network [OSTI]

    Kentaro Tanabe; Seiju Ohashi; Tetsuya Shiromizu

    2010-11-19T23:59:59.000Z

    In higher dimensions than four, conventional uniqueness theorem in asymptotically flat space-times does not hold, i.e., black objects can not be classified only by the mass, angular momentum and charge. In this paper, we define multipole moments for black objects and show that Myers-Perry black hole and black ring can be distinguished by quadrupole moments. This consideration gives us a new insight for the uniqueness theorem for black objects in higher dimensions.

  15. Search for Lepton Flavour Violating Decays of Heavy Resonances and Quantum Black Holes to electron/muon Pairs in pp Collisions at a centre of mass energy of 8 TeV

    E-Print Network [OSTI]

    CMS Collaboration

    2015-01-01T23:59:59.000Z

    A search for heavy states decaying into the e$\\mu$ final state has been performed using an integrated luminosity of $19.7~\\text{fb}^{-1}$ of $8\\,\\text{TeV}$ proton-proton collision data recorded with the CMS detector at the LHC. No evidence for physics beyond the Standard Model is observed in the invariant mass spectrum of selected e$\\mu$ pairs. 95$\\%$ CL upper limits are set on the cross section times branching ratio of different signals arising in theories of new physics with lepton flavour violation in interactions involving charged leptons. In the framework of TeV-scale quantum gravity from a renormalization of Newton's constant, exclusion limits are set on the production threshold of quantum black holes for threshold masses below $1.99\\,\\text{TeV}$, and in extra-dimensional models the bounds range from $2.36\\,\\text{TeV}$ for one extra dimension to $3.63\\,\\text{TeV}$ for six extra dimensions. Scenarios of resonant tau sneutrino LSP production in R-parity violating supersymmetry are excluded for LSP masses...

  16. Applications of High-Resolution Electrospray Ionization Mass Spectrometry to Measurements of Average Oxygen to Carbon Ratios in Secondary Organic Aerosols

    SciTech Connect (OSTI)

    Bateman, Adam P.; Laskin, Julia; Laskin, Alexander; Nizkorodov, Sergey

    2012-07-02T23:59:59.000Z

    The applicability of high resolution electrospray ionization mass spectrometry (HR ESI-MS) to measurements of the average oxygen to carbon ratio (O/C) in organic aerosols was investigated. Solutions with known average O/C containing up to 10 standard compounds representative of secondary organic aerosol (SOA) were analyzed and corresponding electrospray ionization efficiencies were quantified. The assumption of equal ionization efficiency commonly used in estimating O/C ratios of organic aerosols was found to be reasonably accurate. We found that the accuracy of the measured O/C ratios increases by averaging the values obtained from both (+) and (-) modes. A correlation was found between the ratio of the ionization efficiencies in the positive and negative ESI modes with the octanol-water partition constant, and more importantly, with the compound's O/C. To demonstrate the utility of this correlation for estimating average O/C values of unknown mixtures, we analyzed the ESI (+) and ESI (-) data for SOA produced by oxidation of limonene and isoprene and compared to online O/C measurements using an aerosol mass spectrometer (AMS). This work demonstrates that the accuracy of the HR ESI-MS methods is comparable to that of the AMS, with the added benefit of molecular identification of the aerosol constituents.

  17. Dynamics of Primordial Black Hole Formation

    E-Print Network [OSTI]

    J. C. Niemeyer; K. Jedamzik

    1999-01-21T23:59:59.000Z

    We present a numerical investigation of the gravitational collapse of horizon-size density fluctuations to primordial black holes (PBHs) during the radiation-dominated phase of the Early Universe. The collapse dynamics of three different families of initial perturbation shapes, imposed at the time of horizon crossing, is computed. The perturbation threshold for black hole formation, needed for estimations of the cosmological PBH mass function, is found to be $\\delta_{\\rm c} \\approx 0.7$ rather than the generally employed $\\delta_{\\rm c} \\approx 1/3$, if $\\delta$ is defined as $\\Delta M/\\mh$, the relative excess mass within the initial horizon volume. In order to study the accretion onto the newly formed black holes, we use a numerical scheme that allows us to follow the evolution for long times after formation of the event horizon. In general, small black holes (compared to the horizon mass at the onset of the collapse) give rise to a fluid bounce that effectively shuts off accretion onto the black hole, while large ones do not. In both cases, the growth of the black hole mass owing to accretion is insignificant. Furthermore, the scaling of black hole mass with distance from the formation threshold, known to occur in near-critical gravitational collapse, is demonstrated to apply to primordial black hole formation.

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

    E-Print Network [OSTI]

    Lake, Matthew J

    2015-01-01T23:59:59.000Z

    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...

  19. Combustion properties of Kraft Black Liquors

    SciTech Connect (OSTI)

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

    1993-04-01T23:59:59.000Z

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

  20. Primordial black holes and asteroid danger

    E-Print Network [OSTI]

    Alexander Shatskiy

    2008-02-21T23:59:59.000Z

    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.

  1. Multipole moments of bumpy black holes

    E-Print Network [OSTI]

    Vigeland, Sarah Jane

    General relativity predicts the existence of black holes, compact objects whose spacetimes depend only on their mass, spin, and charge in vacuum (the “no-hair” theorem). As various observations probe deeper into the strong ...

  2. Superconducting Hair on Charged Black String Background

    E-Print Network [OSTI]

    Lukasz Nakonieczny; Marek Rogatko

    2012-01-25T23:59:59.000Z

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

  3. Approximate initial data for binary black holes

    E-Print Network [OSTI]

    Kenneth A. Dennison; Thomas W. Baumgarte; Harald P. Pfeiffer

    2006-08-26T23:59:59.000Z

    We construct approximate analytical solutions to the constraint equations of general relativity for binary black holes of arbitrary mass ratio in quasicircular orbit. We adopt the puncture method to solve the constraint equations in the transverse-traceless decomposition and consider perturbations of Schwarzschild black holes caused by boosts and the presence of a binary companion. A superposition of these two perturbations then yields approximate, but fully analytic binary black hole initial data that are accurate to first order in the inverse of the binary separation and the square of the black holes' momenta.

  4. Surface Reductive Capacity of Carbon Nanomaterials after Various Heating and Aging Processes 

    E-Print Network [OSTI]

    Lee, Chunghoon

    2012-10-19T23:59:59.000Z

    , commercially available carbon black, carbon nanotubes, standard reference materials, fullerenes, graphenes and acetylene soot generated in the lab were used. The carbon nanomaterials were subjected to heating at various temperatures in various atmospheres up...

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

    SciTech Connect (OSTI)

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

    2011-05-15T23:59:59.000Z

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

  6. Quantum Black Hole Model and Hawking's Radiation

    E-Print Network [OSTI]

    V. A. Berezin

    1996-02-12T23:59:59.000Z

    The black hole model with a self-gravitating charged spherical symmetric dust thin shell as a source is considered. The Schroedinger-type equation for such a model is derived. This equation appeared to be a finite differences equation. A theory of such an equation is developed and general solution is found and investigated in details. The discrete spectrum of the bound state energy levels is obtained. All the eigenvalues appeared to be infinitely degenerate. The ground state wave functions are evaluated explicitly. The quantum black hole states are selected and investigated. It is shown that the obtained black hole mass spectrum is compatible with the existence of Hawking's radiation in the limit of low temperatures both for large and nearly extreme Reissner-Nordstrom black holes. The above mentioned infinite degeneracy of the mass (energy) eigenvalues may appeared helpful in resolving the well known information paradox in the black hole physics.

  7. Particle Acceleration in Rotating Modified Hayward and Bardeen Black Holes

    E-Print Network [OSTI]

    Behnam Pourhassan; Ujjal Debnath

    2015-06-10T23:59:59.000Z

    In this paper we consider rotating modified Hayward and Bardeen black holes as particle accelerators. We investigate the the center of mass energy of two colliding neutral particles with same rest masses falling from rest at infinity to near the horizons of the mentioned black holes. We also investigate the range of the particle's angular momentum and the orbit of the particle.

  8. Particle Acceleration in Rotating Modified Hayward and Bardeen Black Holes

    E-Print Network [OSTI]

    Pourhassan, Behnam

    2015-01-01T23:59:59.000Z

    In this paper we consider rotating modified Hayward and Bardeen black holes as particle accelerators. We investigate the the center of mass energy of two colliding neutral particles with same rest masses falling from rest at infinity to near the horizons of the mentioned black holes. We also investigate the range of the particle's angular momentum and the orbit of the particle.

  9. Pulsed combustion process for black liquor gasification

    SciTech Connect (OSTI)

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

    1991-02-01T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Cheng-Yi Sun

    2009-03-14T23:59:59.000Z

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

  11. Energy decomposition within Einstein-Born-Infeld black holes

    E-Print Network [OSTI]

    Jonas P. Pereira; Jorge A. Rueda

    2015-03-09T23:59:59.000Z

    We analyze the consequences of the recently found generalization of the Christodoulou-Ruffini black hole mass decomposition for Einstein-Born-Infeld black holes [characterized by the parameters $(Q,M,b)$, where $M = M(M_{irr},Q,b)$, $b$ scale field, $Q$ charge, $M_{irr}$ "irreducible mass", physically meaning the energy of a black hole when its charge is null] and their interactions. We show in this context that their description is largely simplified and can basically be split into two families depending upon the parameter $b|Q|$. If $b|Q|\\leq 1/2$, then black holes could have even zero irreducible masses and they always exhibit single, non degenerated, horizons. If $b|Q|>1/2$, then an associated black hole must have a minimum irreducible mass (related to its minimum energy) and has two horizons up to a transitional irreducible mass. For larger irreducible masses, single horizon structures raise again. By assuming that black holes emit thermal uncharged scalar particles, we further show in light of the black hole mass decomposition that one satisfying $b|Q|>1/2$ takes an infinite amount of time to reach the zero temperature, settling down exactly at its minimum energy. Finally, we argue that depending on the fundamental parameter $b$, the radiation (electromagnetic and gravitational) coming from Einstein-Born-Infeld black holes could differ significantly from Einstein-Maxwell ones. Hence, it could be used to assess such a parameter.

  12. Sequestration of terrigenous organic carbon on the northern California shelf : role of hyperpycnal flows

    E-Print Network [OSTI]

    Moeremans, Raphaële E.

    2011-01-01T23:59:59.000Z

    analyzed for total mass, calcium carbonate, biogenic silica,matter and fluxes of calcium carbonate varied similarly toand biological production. Calcium carbonate and combustible

  13. CARBON-CARBON COMPOSITE ALLCOMP Carbon-Carbon Composite

    E-Print Network [OSTI]

    Rollins, Andrew M.

    materials. MATERIALS AND DESIRED DATA Carbon-Carbon Composites(T300 & SWB): Crush Resistance, Bend StrengthCARBON-CARBON COMPOSITE ALLCOMP Carbon-Carbon Composite · C-C supplied in two forms · T300: C strength 4340 steel, carbon-carbon composite, and Carbon-Silicon Carbide composite were tested to examine

  14. Formation of Carbon Dwarfs

    E-Print Network [OSTI]

    Charles L. Steinhardt; Dimitar D. Sasselov

    2012-01-27T23:59:59.000Z

    We consider the formation of dwarf carbon stars via accretion from a carbon AGB companion in light of the new 107 object sample of Downes et al. (2004). This sample is now large enough to allow good mass determination via comparison of a composite spectrum to theoretical atmospheric models. Carbon dwarfs of spectral type M are indeed main sequence M dwarfs with enhanced metallicity and carbon abundance. We also calculate the predicted abundance of both M and of F/G carbon dwarfs, and show that the latter should be falsifiable in the near future.

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

    E-Print Network [OSTI]

    Gilli, Adrian

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

  16. Compton Scattering on Black Body Photons

    E-Print Network [OSTI]

    Lowell S. Brown; Ronald S. Steinke

    1996-09-27T23:59:59.000Z

    We examine Compton scattering of electrons on black body photons in the case where the electrons are highly relativistic, but the center of mass energy is small in comparison with the electron mass. We derive the partial lifetime of electrons in the LEP accelerator due to this form of scattering in the vacuum beam pipe and compare it with previous results.

  17. The Role of Primordial Kicks on Black Hole Merger Rates

    E-Print Network [OSTI]

    Miroslav Micic; Tom Abel; Steinn Sigurdsson

    2006-09-06T23:59:59.000Z

    Primordial stars are likely to be very massive $\\geq30\\Msun$, form in isolation, and will likely leave black holes as remnants in the centers of their host dark matter halos in the mass range $10^{6}-10^{10}\\Ms$. Such early black holes, at redshifts z$\\gtsim10$, could be the seed black holes for the many supermassive black holes found in galaxies in the local universe. If they exist, their mergers with nearby supermassive black holes may be a prime signal for long wavelength gravitational wave detectors. We simulate formation of black holes in the center of high redshift dark matter halos and explore implications of initial natal kick velocities conjectured by some formation models. The central concentration of early black holes in present day galaxies is reduced if they are born even with moderate kicks of tens of km/s. The modest kicks allow the black holes to leave their parent halo, which consequently leads to dynamical friction being less effective on the lower mass black holes as compared to those still embedded in their parent halos. Therefore, merger rates may be reduced by more than an order of magnitude. Using analytical and illustrative cosmological N--body simulations we quantify the role of natal kicks of black holes formed from massive metal free stars on their merger rates with supermassive black holes in present day galaxies. Our results also apply to black holes ejected by the gravitational slingshot mechanism.

  18. RHIC | Black Holes?

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

    Black Holes at RHIC? Further discussion by Physicist Dmitri Kharzeev on why RHIC cannot produce a real gravitational black hole Black holes are among the most mysterious objects in...

  19. Topological black holes in Horava-Lifshitz gravity

    SciTech Connect (OSTI)

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

    2009-07-15T23:59:59.000Z

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

  20. Optimization of Acetylene Black Conductive Additive and Polyvinylidene Difluoride Composition for High Power Rechargeable Lithium-Ion Cells

    E-Print Network [OSTI]

    Liu, G.; Zheng, H.; Battaglia, V.S.; Simens, A.S.; Minor, A.M.; Song, X.

    2007-01-01T23:59:59.000Z

    of Acetylene Black Conductive Additive and Polyvinylidenematerials, conductive additives and a polymer binder tohighly conductive carbon additives to improve the particle

  1. black-bean-salad

    E-Print Network [OSTI]

    Date: Mon, 22 Nov 93 13:06:59 PST From: Jane Colman BLACK BEAN SALAD 3 cups dried black beans, soaked and cooked 3-4 ears ...

  2. Rotating charged hairy black hole in (2+1) dimensions and particle acceleration

    E-Print Network [OSTI]

    J. Sadeghi; B. Pourhassan; H. Farahani

    2013-10-26T23:59:59.000Z

    In this paper we construct rotating charged hairy black hole in (2+1) dimensions for infinitesimal black hole charge and rotation parameters. Then we consider this black hole as particle accelerator and calculate the center-of-mass energy of two colliding test particles near the rotating charged hairy black hole in (2+1) dimensions. As we expected, the center-of-mass energy has infinite value.

  3. Particle Acceleration Around 5-dimensional Kerr Black Hole

    E-Print Network [OSTI]

    Ahmadjon Abdujabbarov; Naresh Dadhich; Bobomurat Ahmedov; Husan Eshkuvatov

    2013-12-11T23:59:59.000Z

    On the lines of the 4-dimensional Kerr black hole we consider the particle acceleration near a 5-dimensional Kerr black hole which has the two rotation parameters. It turns out that the center of mass energy of the two equal mass colliding particles as expected diverges for the extremal black hole and there is a symmetry in the results for $\\theta = 0, \\pi/2$. Because of the two rotation parameters, $r=0$ can be a horizon without being a curvature singularity. It is shown that the acceleration of particles to high energies near the 5-D extreme rotating black hole avoids fine-tuning of the angular momentum of particles.

  4. Some remarks on black hole thermodynamics

    E-Print Network [OSTI]

    R. Y. Chiao

    2011-02-04T23:59:59.000Z

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

  5. The Role of Primordial Kicks on Black Hole Merger Rates

    E-Print Network [OSTI]

    Miroslav Micic; Tom Abel; Steinn Sigurdsson

    2006-09-15T23:59:59.000Z

    Primordial stars are likely to be very massive >30 Msun, form in isolation, and will likely leave black holes as remnants in the centers of their host dark matter halos. We expect primordial stars to form in halos in the mass range 10^6-10^10 Msun. Some of these early black holes, formed at redshifts z>10, could be the seed black hole for a significant fraction of the supermassive black holes found in galaxies in the local universe. If the black hole descendants of the primordial stars exist, their mergers with nearby supermassive black holes may be a prime candidate for long wavelength gravitational wave detectors. We simulate formation and evolution of dark matter halos in LambdaCDM universe. We seed high-redshift dark matter halos with early black holes, and explore the merger history of the host halos and the implications of black hole's kick velocities arising from their coalescence. The central concentration of low mass early black holes in present day galaxies is reduced if they experience even moderate kicks of tens of km/s. Even such modest kicks allow the black holes to leave their parent halo, which consequently leads to dynamical friction being less effective on the low mass black holes that were ejected, compared to those still embedded in their parent halos. Therefore, merger rates with central supermassive black holes in the largest halos may be reduced by more than an order of magnitude. Using analytical and illustrative cosmological N-body simulations, we quantify the role of kicks on the merger rates of black holes formed from massive metal free stars with supermassive black holes in present day galaxies.

  6. Fabrication of activated carbon fibers/carbon aerogels composites by gelation and supercritical drying

    E-Print Network [OSTI]

    Liu, Jie

    Fabrication of activated carbon fibers/carbon aerogels composites by gelation and supercritical August 2003) Activated carbon fiber/carbon aerogel (ACF/CA) composites were fabricated by gelling. The ACFs can reinforce the related carbon aerogels when they originally have low mass density and are weak

  7. Croatian Black Hole School 2010 lecture notes on IMBHs in GCs

    E-Print Network [OSTI]

    Mario Pasquato

    2010-08-26T23:59:59.000Z

    Black holes are fascinating objects. As a class of solutions to the Einstein equations they have been studied a great deal, yielding a wealth of theoretical results. But do they really exist? What do astronomers really mean when they claim to have observational evidence of their existence? To answer these questions, I will focus on a particular range of black-hole masses, approximately from 100 to 10000 solar masses. Black holes of this size are named Intermediate Mass Black Holes (IMBHs) and their existence is still heavily disputed, so they will be perfect for illustrating the observational challenges faced by a black hole hunter

  8. Pt/CARBON XEROGEL CATALYSTS FOR PEM FUEL CELLS Nathalie JOBa

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Pt/CARBON XEROGEL CATALYSTS FOR PEM FUEL CELLS Nathalie JOBa , Frédéric MAILLARDb , Jean, France ABSTRACT Carbon xerogels have been used to replace carbon black as catalyst support at the cathode in this electrode. Carbon xerogels are very clean nanostructured carbons with well-defined pore texture, which

  9. Improving snow albedo processes in WRF/SSiB regional climate model to assess impact of dust and black carbon in snow on surface energy balance and hydrology over western U.S.

    E-Print Network [OSTI]

    2015-01-01T23:59:59.000Z

    Basin: 1. A 6 year record of energy balance, radiation, andorganic carbon aerosol from energy-related combustion, 1850–carbon in snow on surface energy balance and hydrology over

  10. Rotating charged cylindrical black holes as particle accelerators

    SciTech Connect (OSTI)

    Said, Jackson Levi [Physics Department, University of Malta, Msida MSD 2080 (Malta); Adami, Kristian Zarb [Physics Department, University of Malta, Msida MSD 2080 (Malta); Physics Department, University of Oxford, Oxford, OX1 3RH (United Kingdom)

    2011-05-15T23:59:59.000Z

    It has recently been pointed out that arbitrary center-of-mass energies may be obtained for particle collisions near the horizon of an extremal Kerr black hole. We investigate this mechanism in cylindrical topology. In particular we consider the center-of-mass energies of a cylindrical black hole with an extremal rotation and charge parameter. The geodesics are first derived with a rotating charged cylindrical black hole producing the background gravitational field. Finally the center-of-mass is determined for this background and its extremal limit is taken.

  11. A Quantum Material Model of Static Schwarzschild Black Holes

    E-Print Network [OSTI]

    S. -T. Sung

    1997-03-16T23:59:59.000Z

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

  12. Classical and Quantum Properties of Liouville Black Holes

    E-Print Network [OSTI]

    R. B. Mann

    1994-04-25T23:59:59.000Z

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

  13. Brownian Motion of Black Holes in Dense Nuclei

    E-Print Network [OSTI]

    David Merritt; Peter Berczik; Frederik Laun

    2006-10-18T23:59:59.000Z

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

  14. Characterization of Black Carbon Mixing State

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

    Sedlacek, Arthur; S, Satheesh; Springston, Stephen

    This measurement characterizes the types of BC emissions that result in near­surface BC­ containing particles in a region that is dominated by biomass and open pit/stove cooking. Specifically, examine three primary BC emission sources: (i) urban setting (e.g., fossil fuel emissions); and (ii) biomass burning. Source (i) are captured at the Indian Institute of Science (IISc) in Bangalore. Biomass emissions (ii) contains a series of 1­2 day measurement excursions to the rural area surrounding Bangalore.

  15. The structure of the carbon black flame 

    E-Print Network [OSTI]

    Anderson, W. Kermi

    1945-01-01T23:59:59.000Z

    Wbyo. a1y dWoAmv AcWdp PcWgy nS bomfHdyf AB AHovnvE W QyR mP EWS nSSHnvE Pomg W cWuW Rnb nv W oySRondRy6f SHbbcB mP Wno. a1y EWS AHovS lnR1 vm boy6gnqRHoy mP Wno Wvf R1y PcWgy AmHvfWonyS Woy fyRyognvyf AB R1y bmnvRS WR l1nd1 nvRyofnPPHSnmv mP EWS Wvf... RygbyoWRHoy gyWSHoygyvRS AHR. EnuyS vm nvPmogWRnmv WS Rm R1y SmHody mP R1y fWRW HSyf * mo R1y6 gyR1mf AB l1nd1 R1yB lyoy mARWnvyf. aygbyoWRHoyS oWvEnvE Pomg 0'wJN. Rm U'wwJN. lyoy oydmofyf. Iv EyvyoWc, nR gWB Ay SRWRyf R1WR R1mHE1 R1y inRh yo...

  16. Controls on black carbon storage in soils

    E-Print Network [OSTI]

    Czimczik, Claudia I; Masiello, Caroline A

    2007-01-01T23:59:59.000Z

    matter upon sorp- tion to goethite and kaolinite, Chem.organic matter fractions to goethite (alpha-FeOOH): Effectreactive with minerals like goethite [Kaiser, 2003; Kaiser

  17. Applications of High-Resolution Electrospray Ionization Mass...

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

    High-Resolution Electrospray Ionization Mass Spectrometry to Measurements of Average Oxygen to Carbon Ratios in Applications of High-Resolution Electrospray Ionization Mass...

  18. Small Hairy Black Holes in Global AdS Spacetime

    E-Print Network [OSTI]

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

    2010-05-16T23:59:59.000Z

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

  19. Improved methods for simulating nearly extremal binary black holes

    E-Print Network [OSTI]

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

    2014-12-04T23:59:59.000Z

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

  20. Ultimate Isotope Precision for Carbonates Thermo Scientific

    E-Print Network [OSTI]

    Lachniet, Matthew S.

    Ultimate Isotope Precision for Carbonates Thermo Scientific KIEL IV Carbonate Device Part of Thermo integration cycle Ultimate Isotope Precision for Carbonates The Thermo Scientific KIEL IV Carbonate DeviceV Thermo Scientific MAT 253 or the 3-kV DELTA V isotope ratio mass spectrometer meets the requirements

  1. Pair Production of Topological anti de Sitter Black Holes

    E-Print Network [OSTI]

    R. B. Mann

    1996-07-28T23:59:59.000Z

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

  2. Renyi entropies of a black hole from Hawking radiation

    E-Print Network [OSTI]

    A. Bialas; W. Czyz

    2008-01-30T23:59:59.000Z

    Renyi entropies of a black hole are evaluated by counting the states of the Hawking radiation which fills a thin shell surrounding the horizon. The width of the shell is determined from its energy content and the corresponding mass defect. The Bekenstein-Hawking formula for the entropy of the black hole is correctly reproduced.

  3. The mass spectrum of compact remnants from the PARSEC stellar evolution tracks

    E-Print Network [OSTI]

    Spera, Mario; Bressan, Alessandro

    2015-01-01T23:59:59.000Z

    The mass spectrum of stellar-mass black holes (BHs) is highly uncertain. Dynamical mass measurements are available only for few ($\\sim{}10$) BHs in X-ray binaries, while theoretical models strongly depend on the hydrodynamics of supernova (SN) explosions and on the evolution of massive stars. In this paper, we present and discuss the mass spectrum of compact remnants that we obtained with SEVN, a new public population-synthesis code, which couples the PARSEC stellar evolution tracks with up-to-date recipes for SN explosion (depending on the Carbon-Oxygen mass of the progenitor, on the compactness of the stellar core at pre-SN stage, and on a recent two-parameter criterion based on the dimensionless entropy per nucleon at pre-SN stage). SEVN can be used both as a stand-alone code and in combination with direct-summation N-body codes (Starlab, HiGPUs). The PARSEC stellar evolution tracks currently implemented in SEVN predict significantly larger values of the Carbon-Oxygen core mass with respect to previous mod...

  4. Combustion of biomass as a global carbon sink

    E-Print Network [OSTI]

    Ball, Rowena

    2008-01-01T23:59:59.000Z

    This note is intended to highlight the important role of black carbon produced from biomass burning in the global carbon cycle, and encourage further research in this area. Consideration of the fundamental physical chemistry of cellulose thermal decomposition suggests that suppression of biomass burning or biasing burning practices to produce soot-free flames must inevitably transfer more carbon to the atmosphere. A simple order-of-magnitude quantitative analysis indicates that black carbon may be a significant carbon reservoir that persists over geological time scales.

  5. Aged black carbon identified in marine dissolved organic carbon

    E-Print Network [OSTI]

    Ziolkowski, Lori A; Druffel, Ellen R.M.

    2010-01-01T23:59:59.000Z

    pool in the northeast Pacific Ocean, Deep Sea Res. , Part I,?445‰ in the deep NE Pacific Ocean (Table S1). The Suwanneein the northeast Pacific Ocean. If the BC in the Amazon

  6. The Environmental Impact of Supermassive Black Holes

    E-Print Network [OSTI]

    Abraham Loeb

    2004-08-10T23:59:59.000Z

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

  7. Investigating Dark Energy with Black Hole Binaries

    E-Print Network [OSTI]

    Laura Mersini-Houghton; Adam Kelleher

    2009-06-08T23:59:59.000Z

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

  8. Structure of the Inner Singularity of a Spherical Black Hole

    E-Print Network [OSTI]

    A. Bonanno; S. Droz; W. Israel; S. M. Morsink

    1994-03-10T23:59:59.000Z

    We review the evidence for and against the possibility that the inner singularity of a black hole contains a lightlike segment which is locally mild and characterized by mass inflation.

  9. Stimuli-Tailored Dispersion State of Aqueous Carbon Nanotube Suspensions and Solid Polymer Nanocomposites

    E-Print Network [OSTI]

    Etika, Krishna

    2012-02-14T23:59:59.000Z

    -controlled dispersion of carbon nanotubes could have a variety of applications in nanoelectronics, sensing, and drug and gene delivery systems. Furthermore, this dissertation also contains a published study focused on controlling the dispersion state of carbon black (CB...

  10. Structure of the Spherical Black Hole Interior

    E-Print Network [OSTI]

    A. Bonanno; S. Droz; W. Israel; S. M. Morsink

    1994-11-18T23:59:59.000Z

    The internal structure of a charged spherical black hole is still a topic of debate. In a nonrotating but aspherical gravitational collapse to form a spherical charged black hole, the backscattered gravitational wave tails enter the black hole and are blueshifted at the Cauchy horizon. This has a catastrophic effect if combined with an outflux crossing the Cauchy horizon: a singularity develops at the Cauchy horizon and the effective mass inflates. Recently a numerical study of a massless scalar field in the \\RN background suggested that a spacelike singularity may form before the Cauchy horizon forms. We will show that there exists an approximate analytic solution of the scalar field equations which allows the mass inflation singularity at the Cauchy horizon to exist. In particular, we see no evidence that the Cauchy horizon is preceded by a spacelike singularity.

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

    E-Print Network [OSTI]

    Ben L. Shepherd; Elizabeth Winstanley

    2012-06-25T23:59:59.000Z

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

  12. Black Pine Engineering

    Broader source: Energy.gov [DOE]

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

  13. Black Bean Burrito Ingredients

    E-Print Network [OSTI]

    Liskiewicz, Maciej

    under running water to remove sodium. 2. Heat beans, corn and salsa together. 3. Spread 1/8 salsaBlack Bean Burrito Ingredients: 15 ounces black beans, canned, drained and rinsed 10 ounces corn cheddar cheese, low-fat, shredded 8 whole wheat flour tortillas Directions 1. Drain and rinse black beans

  14. Extrasolar Carbon Planets

    E-Print Network [OSTI]

    Marc J. Kuchner; S. Seager

    2005-05-02T23:59:59.000Z

    We suggest that some extrasolar planets planets and low-mass white dwarf planets are especially good candidate members of this new class of planets, but these objects could also conceivably form around stars like the Sun. This planet-formation pathway requires only a factor of two local enhancement of the protoplanetary disk's C/O ratio above solar, a condition that pileups of carbonaceous grains may create in ordinary protoplanetary disks. Hot, Neptune-mass carbon planets should show a significant paucity of water vapor in their spectra compared to hot planets with solar abundances. Cooler, less massive carbon planets may show hydrocarbon-rich spectra and tar-covered surfaces. The high sublimation temperatures of diamond, SiC, and other carbon compounds could protect these planets from carbon depletion at high temperatures.

  15. Variability of building environmental assessment tools on evaluating carbon emissions

    SciTech Connect (OSTI)

    Ng, S. Thomas, E-mail: tstng@hkucc.hku.hk; Chen Yuan, E-mail: chenyuan4@gmail.com; Wong, James M.W., E-mail: jmwwong@hku.hk

    2013-01-15T23:59:59.000Z

    With an increasing importance of sustainability in construction, more and more clients and designers employ building environmental assessment (BEA) tools to evaluate the environmental friendliness of their building facilities, and one important aspect of evaluation in the BEA models is the assessment of carbon emissions. However, in the absence of any agreed framework for carbon auditing and benchmarking, the results generated by the BEA tools might vary significantly which could lead to confusion or misinterpretation on the carbon performance of a building. This study thus aims to unveil the properties of and the standard imposed by the current BEA models on evaluating the life cycle carbon emissions. The analyses cover the (i) weighting of energy efficiency and emission levels among various environmental performance indicators; (ii) building life cycle stages in which carbon is taken into consideration; (iii) objectiveness of assessment; (iv) baseline set for carbon assessment; (v) mechanism for benchmarking the emission level; and (v) limitations of the carbon assessment approaches. Results indicate that the current BEA schemes focus primarily on operational carbon instead of the emissions generated throughout the entire building life cycle. Besides, the baseline and benchmark for carbon evaluation vary significantly among the BEA tools based on the analytical results of a hypothetical building. The findings point to the needs for a more transparent framework for carbon auditing and benchmarking in BEA modeling. - Highlights: Black-Right-Pointing-Pointer Carbon emission evaluation in building environmental assessment schemes are studied. Black-Right-Pointing-Pointer Simulative carbon emission is modeled for building environmental assessment schemes. Black-Right-Pointing-Pointer Carbon assessments focus primarily on operational stage instead of entire lifecycle. Black-Right-Pointing-Pointer Baseline and benchmark of carbon assessment vary greatly among BEA schemes. Black-Right-Pointing-Pointer A more transparent and comprehensive framework for carbon assessment is required.

  16. Acceleration of particles in Einstein-Maxwell-Dilaton black hole

    E-Print Network [OSTI]

    Pu-Jian Mao; Ran Li; Lin-Yu Jia; Ji-Rong Ren

    2011-03-08T23:59:59.000Z

    It has been recently pointed out that, under certain conditions, the energy of particles accelerated by black holes in the center-of-mass frame can become arbitrarily high. In this Letter, we study the collision of two particles around the four-dimensional Kaluza-Klein black hole in Einstein-Maxwell-Dilaton theory. We find that the center-of-mass energy for a pair of colliding particles is unlimited at the horizon of charged nonrotating and extremal rotating Kaluza-Klein black hole.

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

    E-Print Network [OSTI]

    Sharmanthie Fernando

    2014-08-21T23:59:59.000Z

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

  18. Comments on absorption cross section for Chern-Simons black holes in five dimensions

    E-Print Network [OSTI]

    P. A. González; Joel Saavedra

    2011-05-12T23:59:59.000Z

    In this paper we study the effects of black hole mass on the absorption cross section for a massive scalar field propagating in a 5-dimensional topological Chern-Simons black hole at the low-frequency limit. We consider the two branches of black hole solutions $(\\alpha=\\pm 1)$ and we show that, if the mass of black hole increase the absorption cross section decreases at the zero-frequency limit for the branch $\\alpha=-1$ and for the other branch, $\\alpha=1$, the behavior is opposite, if the black hole mass increase the absorption cross section increases. Also we find that beyond a certain frequency value, the mass black hole does not affect the absorption cross section.

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

    E-Print Network [OSTI]

    A. K. Chaudhuri

    2003-01-08T23:59:59.000Z

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

  20. On Quasar Masses and Quasar Host Galaxies

    E-Print Network [OSTI]

    Ari Laor

    1998-07-27T23:59:59.000Z

    The mass of massive black holes in quasar cores can be deduced using the typical velocities of Hb-emitting clouds in the Broad Line Region (BLR) and the size of this region. However, this estimate depends on various assumptions and is susceptible to large systematic errors. The Hb-deduced black hole mass in a sample of 14 bright quasars is found here to correlate with the quasar host galaxy luminosity, as determined with the Hubble Space Telescope (HST). This correlation is similar to the black hole mass vs. bulge luminosity correlation found by Magorrian et al. in a sample of 32 nearby normal galaxies. The similarity of the two correlations is remarkable since the two samples involve apparently different types of objects and since the black hole mass estimates in quasars and in nearby galaxies are based on very different methods. This similarity provides a ``calibration'' of the Hb-deduced black hole mass estimate, suggesting it is accurate to +-0.5 on log scale. The similarity of the two correlations also suggests that quasars reside in otherwise normal galaxies, and that the luminosity of quasar hosts can be estimated to +-0.5 mag based on the quasar continuum luminosity and the Hb line width. Future imaging observations of additional broad-line active galaxies with the HST are required in order to explore the extent, slope, and scatter of the black hole mass vs. host bulge luminosity correlation in active galaxies.

  1. Imprint of Accretion Disk-Induced Migration on Gravitational Waves from Extreme Mass Ratio Inspirals

    E-Print Network [OSTI]

    Yunes, Nicolas

    We study the effects of a thin gaseous accretion disk on the inspiral of a stellar-mass black hole into a supermassive black hole. We construct a phenomenological angular momentum transport equation that reproduces known ...

  2. Dynamics of stellar black holes in young star clusters with different metallicities - II. Black hole-black hole binaries

    E-Print Network [OSTI]

    Brunetto Marco Ziosi; Michela Mapelli; Marica Branchesi; Giuseppe Tormen

    2014-05-20T23:59:59.000Z

    In this paper, we study the formation and dynamical evolution of black hole-black hole (BH-BH) binaries in young star clusters (YSCs), by means of N-body simulations. The simulations include metallicity-dependent recipes for stellar evolution and stellar winds, and have been run for three different metallicities (Z = 0.01, 0.1 and 1 Zsun). Following recent theoretical models of wind mass-loss and core-collapse supernovae, we assume that the mass of the stellar remnants depends on the metallicity of the progenitor stars. We find that BH-BH binaries form efficiently because of dynamical exchanges: in our simulations, we find about 10 times more BH-BH binaries than double neutron star binaries. The simulated BH-BH binaries form earlier in metal-poor YSCs, which host more massive black holes (BHs) than in metal-rich YSCs. The simulated BH-BH binaries have very large chirp masses (up to 80 Msun), because the BH mass is assumed to depend on metallicity, and because BHs can grow in mass due to the merger with stars. The simulated BH-BH binaries span a wide range of orbital periods (10^-3-10^7 yr), and only a small fraction of them (0.3 per cent) is expected to merge within a Hubble time. We discuss the estimated merger rate from our simulations and the implications for Advanced VIRGO and LIGO.

  3. Circumnuclear Media and Accretion Rates of Quiescent Supermassive Black Holes

    E-Print Network [OSTI]

    Generozov, Aleksey; Metzger, Brian D

    2015-01-01T23:59:59.000Z

    We calculate steady-state, one-dimensional hydrodynamic profiles of hot gas in slowly accreting ("quiescent") galactic nuclei for a range of central black hole masses, parameterized gas heating rates, and observationally-motivated stellar density profiles. Mass is supplied to the circumnuclear medium by stellar winds, while energy is injected primarily by stellar winds, supernovae, and black hole feedback. Analytic estimates are derived for the stagnation radius (where the radial velocity of the gas passes through zero) and the black hole accretion rate, as a function of the black hole mass and the gas heating efficiency, the latter being related to the star-formation history. We assess the conditions under which radiative instabilities develop in the hydrostatic region near the stagnation radius, both in the case of a single burst of star formation and for the average star formation history predicted by cosmological simulations. By combining a sample of measured nuclear X-ray luminosities from nearby quiesce...

  4. Spin orientation of supermassive black holes in active galaxies

    E-Print Network [OSTI]

    W. Kollatschny

    2003-11-12T23:59:59.000Z

    Accretion of gas onto a central supermassive black hole is generally accepted to be the source of the emitted energy in active galactic nuclei.The broad emission lines we observe in their optical spectra are probably formed in the wind of an accretion disk at distances of light days to light years from the central black hole. The variable fraction of the emission lines originates at typical distances of only 1 to 50 light days from the central supermassive black hole. We derived a central black hole mass of M_orbital = 1.8 +/-0.4 x 10^7 M_sun in the Seyfert galaxy Mrk110 assuming the broad emission lines are generated in gas clouds orbiting within an accretion disk. This figure depends on the inclination angle of the accretion disk. Here we report on the detection of gravitational redshifted emission in the variable fraction of the broad emission lines. We derive a central black hole mass of M_grav = 14.0 +/-3.0 x 10^7 M_sun. These measurements are independent on the orientation of the accretion disk. The comparison of both black hole mass estimates allows to determine the projection of the central accretion disk angle i to 21 +/-5 deg. in Mrk110 and therefore the orientation of the spin axis of the central black hole.

  5. Following Black Hole Scaling Relations Through Gas-Rich Mergers

    E-Print Network [OSTI]

    Medling, Anne M; Max, Claire E; Sanders, David B; Armus, Lee; Holden, Bradford; Mieda, Etsuko; Wright, Shelley A; Larkin, James E

    2015-01-01T23:59:59.000Z

    We present black hole mass measurements from kinematic modeling of high-spatial resolution integral field spectroscopy of the inner regions of 9 nearby (ultra-)luminous infrared galaxies in a variety of merger stages. These observations were taken with OSIRIS and laser guide star adaptive optics on the Keck I and Keck II telescopes, and reveal gas and stellar kinematics inside the spheres of influence of these supermassive black holes. We find that this sample of black holes are overmassive ($\\sim10^{7-9}$ M$_{Sun}$) compared to the expected values based on black hole scaling relations, and suggest that the major epoch of black hole growth occurs in early stages of a merger, as opposed to during a final episode of quasar-mode feedback. The black hole masses presented are the dynamical masses enclosed in $\\sim$25pc, and could include gas which is gravitationally bound to the black hole but has not yet lost sufficient angular momentum to be accreted. If present, this gas could in principle eventually fuel AGN f...

  6. 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.

  7. Ion mass spectrometry investigations of the discharge during reactive high power pulsed and direct current magnetron sputtering of carbon in Ar and Ar/N{sub 2}

    SciTech Connect (OSTI)

    Schmidt, S.; Greczynski, G.; Jensen, J.; Hultman, L. [Thin Film Physics Div., Department of Physics (IFM), Linkoeping University, SE-581 83 (Sweden); Czigany, Zs. [Institute of Technical Physics and Materials Science, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Konkoly Thege Miklos ut 29-33. H-1121 Budapest (Hungary)

    2012-07-01T23:59:59.000Z

    Ion mass spectrometry was used to investigate discharges formed during high power impulse magnetron sputtering (HiPIMS) and direct current magnetron sputtering (DCMS) of a graphite target in Ar and Ar/N{sub 2} ambient. Ion energy distribution functions (IEDFs) were recorded in time-averaged and time-resolved mode for Ar{sup +}, C{sup +}, N{sub 2}{sup +}, N{sup +}, and C{sub x}N{sub y}{sup +} ions. An increase of N{sub 2} in the sputter gas (keeping the deposition pressure, pulse width, pulse frequency, and pulse energy constant) results for the HiPIMS discharge in a significant increase in C{sup +}, N{sup +}, and CN{sup +} ion energies. Ar{sup +}, N{sub 2}{sup +}, and C{sub 2}N{sup +} ion energies, in turn, did not considerably vary with the changes in working gas composition. The HiPIMS process showed higher ion energies and fluxes, particularly for C{sup +} ions, compared to DCMS. The time evolution of the plasma species was analyzed for HiPIMS and revealed the sequential arrival of working gas ions, ions ejected from the target, and later during the pulse-on time molecular ions, in particular CN{sup +} and C{sub 2}N{sup +}. The formation of fullerene-like structured CN{sub x} thin films for both modes of magnetron sputtering is explained by ion mass-spectrometry results and demonstrated by transmission electron microscopy as well as diffraction.

  8. Dynamics of black holes

    E-Print Network [OSTI]

    Sean A. Hayward

    2009-02-28T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    G. Dillon

    2013-02-15T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Maryland at College Park, University of

    of a sudden drop of the hard X-rays..." ·"The particles (corona/inner disk) are blown away..." ·"Jets have Direct collapse depends on: ·Metal content ·Mass of the core ·Angular momentum Can this model be tested observationally ? #12;HOW ARE FORM BLACK HOLE BINARIES ? CORE COLLAPSE MODELS: (Fryer & Kalogera ; Woosley & Heger

  11. Fabricating solid carbon porous electrodes from powders

    DOE Patents [OSTI]

    Kaschmitter, James L. (Pleasanton, CA); Tran, Tri D. (Livermore, CA); Feikert, John H. (Livermore, CA); Mayer, Steven T. (San Leandro, CA)

    1997-01-01T23:59:59.000Z

    Fabrication of conductive solid porous carbon electrodes for use in batteries, double layer capacitors, fuel cells, capacitive dionization, and waste treatment. Electrodes fabricated from low surface area (<50 m.sup.2 /gm) graphite and cokes exhibit excellent reversible lithium intercalation characteristics, making them ideal for use as anodes in high voltage lithium insertion (lithium-ion) batteries. Electrodes having a higher surface area, fabricated from powdered carbon blacks, such as carbon aerogel powder, carbon aerogel microspheres, activated carbons, etc. yield high conductivity carbon compositives with excellent double layer capacity, and can be used in double layer capacitors, or for capacitive deionization and/or waste treatment of liquid streams. By adding metallic catalysts to be high surface area carbons, fuel cell electrodes can be produced.

  12. Fabricating solid carbon porous electrodes from powders

    DOE Patents [OSTI]

    Kaschmitter, J.L.; Tran, T.D.; Feikert, J.H.; Mayer, S.T.

    1997-06-10T23:59:59.000Z

    Fabrication is described for conductive solid porous carbon electrodes for use in batteries, double layer capacitors, fuel cells, capacitive deionization, and waste treatment. Electrodes fabricated from low surface area (<50 m{sup 2}/gm) graphite and cokes exhibit excellent reversible lithium intercalation characteristics, making them ideal for use as anodes in high voltage lithium insertion (lithium-ion) batteries. Electrodes having a higher surface area, fabricated from powdered carbon blacks, such as carbon aerogel powder, carbon aerogel microspheres, activated carbons, etc. yield high conductivity carbon composites with excellent double layer capacity, and can be used in double layer capacitors, or for capacitive deionization and/or waste treatment of liquid streams. By adding metallic catalysts to high surface area carbons, fuel cell electrodes can be produced. 1 fig.

  13. Causticizing for Black Liquor Gasifiers

    SciTech Connect (OSTI)

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

    2009-01-07T23:59:59.000Z

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

  14. Gravitational energy of rotating black holes

    E-Print Network [OSTI]

    J. W. Maluf; E. F. Martins; A. Kneip

    1996-08-21T23:59:59.000Z

    In the teleparallel equivalent of general relativity the energy density of asymptotically flat gravitational fields can be naturaly defined as a scalar density restricted to a three-dimensional spacelike hypersurface $\\Sigma$. Integration over the whole $\\Sigma$ yields the standard ADM energy. After establishing the reference space with zero gravitational energy we obtain the expression of the localized energy for a Kerr black hole. The expression of the energy inside a surface of constant radius can be explicitly calculated in the limit of small $a$, the specific angular momentum. Such expression turns out to be exactly the same as the one obtained by means of the method preposed recently by Brown and York. We also calculate the energy contained within the outer horizon of the black hole for {\\it any} value of $a$. The result is practically indistinguishable from $E=2M_{ir}$, where $M_{ir}$ is the irreducible mass of the black hole.

  15. Carbon sequestration, optimum forest rotation and their environmental impact

    SciTech Connect (OSTI)

    Kula, Erhun, E-mail: erhun.kula@bahcesehir.edu.tr [Department of Economics, Bahcesehir University, Besiktas, Istanbul (Turkey); Gunalay, Yavuz, E-mail: yavuz.gunalay@bahcesehir.edu.tr [Department of Business Studies, Bahcesehir University, Besiktas, Istanbul (Turkey)

    2012-11-15T23:59:59.000Z

    Due to their large biomass forests assume an important role in the global carbon cycle by moderating the greenhouse effect of atmospheric pollution. The Kyoto Protocol recognises this contribution by allocating carbon credits to countries which are able to create new forest areas. Sequestrated carbon provides an environmental benefit thus must be taken into account in cost-benefit analysis of afforestation projects. Furthermore, like timber output carbon credits are now tradable assets in the carbon exchange. By using British data, this paper looks at the issue of identifying optimum felling age by considering carbon sequestration benefits simultaneously with timber yields. The results of this analysis show that the inclusion of carbon benefits prolongs the optimum cutting age by requiring trees to stand longer in order to soak up more CO{sub 2}. Consequently this finding must be considered in any carbon accounting calculations. - Highlights: Black-Right-Pointing-Pointer Carbon sequestration in forestry is an environmental benefit. Black-Right-Pointing-Pointer It moderates the problem of global warming. Black-Right-Pointing-Pointer It prolongs the gestation period in harvesting. Black-Right-Pointing-Pointer This paper uses British data in less favoured districts for growing Sitka spruce species.

  16. [5] Suh JS, Jeong KS, Lee JS, Han IT. Study of the field-screening effect of highly ordered carbon nanotube arrays. Appl Phys Lett

    E-Print Network [OSTI]

    Chung, Deborah D.L.

    molecular weight polymer. The interfacial strength between carbon fillers and epoxy resin varies for improving and/or optimizing the manufacturing process of epoxy­matrix composites. Epoxy resin filled with various carbons (carbon fiber, carbon nanofiber and carbon black) was studied. The epoxy resin system

  17. Abundance ratios in red-sequence galaxies over a wide mass range: The "X-planes'' for magnesium, calcium, carbon and nitrogen

    E-Print Network [OSTI]

    Smith, Russell J; Hudson, Michael J; Bridges, Terry J

    2009-01-01T23:59:59.000Z

    We analyse the abundance ratios of the light elements Mg, Ca, C and N, relative to Fe, for 147 red-sequence galaxies in the Coma cluster and the Shapley Supercluster. The sample covers a six-magnitude range in luminosity, from giant ellipticals to dwarfs at M^*+4. We exploit the wide mass range to investigate systematic trends in the abundance ratios Mg/Fe, Ca/Fe, C/Fe and N/Fe. We find that each of these ratios can be well modelled using two-parameter relations of the form [X/Fe] = a0 + a1 log sigma + a2 [Fe/H], where sigma is the velocity dispersion. Analysing these ``X-planes'' reveals new structure in the abundance patterns, beyond the traditional one-parameter (e.g. Mg/Fe-sigma) correlations. The X-planes for the alpha elements, Mg and Ca, indicate a positive correlation with velocity dispersion, and simultaneously an anti-correlation with Fe/H (i.e. a1>0 and a20 and a2~0). The explicit dependence of X/Fe on two parameters is evidence that at least two physical processes are at work in setting the abunda...

  18. Carbon Smackdown: Carbon Capture

    ScienceCinema (OSTI)

    Jeffrey Long

    2010-09-01T23:59:59.000Z

    In this July 9, 2010 Berkeley Lab summer lecture, Lab scientists Jeff Long of the Materials Sciences and Nancy Brown of the Environmental Energy Technologies Division discuss their efforts to fight climate change by capturing carbon from the flue gas of power plants, as well as directly from the air

  19. A novel activated carbon for supercapacitors

    SciTech Connect (OSTI)

    Shen, Haijie [Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, College of Chemistry, Xiangtan University, Hunan 411105 (China)] [Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, College of Chemistry, Xiangtan University, Hunan 411105 (China); Liu, Enhui, E-mail: liuenhui99@sina.com.cn [Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, College of Chemistry, Xiangtan University, Hunan 411105 (China)] [Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, College of Chemistry, Xiangtan University, Hunan 411105 (China); Xiang, Xiaoxia; Huang, Zhengzheng; Tian, Yingying; Wu, Yuhu; Wu, Zhilian; Xie, Hui [Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, College of Chemistry, Xiangtan University, Hunan 411105 (China)] [Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, College of Chemistry, Xiangtan University, Hunan 411105 (China)

    2012-03-15T23:59:59.000Z

    Highlights: Black-Right-Pointing-Pointer A novel activated carbon was prepared from phenol-melamine-formaldehyde resin. Black-Right-Pointing-Pointer The carbon has large surface area with microporous, and high heteroatom content. Black-Right-Pointing-Pointer Heteroatom-containing functional groups can improve the pseudo-capacitance. Black-Right-Pointing-Pointer Physical and chemical properties lead to the good electrochemical properties. -- Abstract: A novel activated carbon has been prepared by simple carbonization and activation of phenol-melamine-formaldehyde resin which is synthesized by the condensation polymerization method. The morphology, thermal stability, surface area, elemental composition and surface chemical composition of samples have been investigated by scanning electron microscope, thermogravimetry and differential thermal analysis, Brunauer-Emmett-Teller measurement, elemental analysis and X-ray photoelectron spectroscopy, respectively. Electrochemical properties have been studied by cyclic voltammograms, galvanostatic charge/discharge, and electrochemical impedance spectroscopy measurements in 6 mol L{sup -1} potassium hydroxide. The activated carbon shows good capacitive behavior and the specific capacitance is up to 210 F g{sup -1}, which indicates that it may be a promising candidate for supercapacitors.

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

    SciTech Connect (OSTI)

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

    1995-08-01T23:59:59.000Z

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

  1. Phantom energy accretion onto a black hole in Horava Lifshitz gravity

    E-Print Network [OSTI]

    G. Abbas

    2013-03-27T23:59:59.000Z

    In this Letter, we examine the phantom energy accretion onto a Kehagias-Sfetsos black hole in Ho$\\check{r}$ava Lifshitz gravity. To discuss the accretion process onto the black hole, the equations of phantom flow near the black hole have been derived. It is found that mass of the black hole decreases because of phantom accretion. We discuss the conditions for critical accretion. Graphically, it has been found that the critical accretion phenomena is possible for different values of parameters. The results for the Schwarzschild black hole can be recovered in the limiting case.

  2. Rotating Hairy Black Holes

    E-Print Network [OSTI]

    B. Kleihaus; J. Kunz

    2000-12-20T23:59:59.000Z

    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.

  3. margrets-black-beans

    E-Print Network [OSTI]

    COM (Robert L. Simmons) Black Beans (Margret Simmons) 2 lbs. dry black beans soaked 8 hrs/overnight 1 qt. veggie stock soaking water plus enough ... 10 garlic cloves finely chopped 1/2 cup cooking sherry 1 tsp. allspice (ground) 1 lemon ...

  4. Weighing Black Holes in high-z SCUBA Galaxies

    E-Print Network [OSTI]

    Alexander, D M

    2006-01-01T23:59:59.000Z

    Deep SCUBA surveys have uncovered a population of dust-enshrouded star-forming galaxies at z~2. Using the ultra-deep 2 Ms Chandra Deep Field-North survey we recently showed that a large fraction of these systems are also undergoing intense black-hole growth. Here we provide further constraints on the properties of the black holes in SCUBA galaxies using the virial black-hole mass estimator. We show that typical SCUBA galaxies are likely to host black holes with M_BH~10^7-10^8 M_solar which are accreting at, or close to, the Eddington limit. These results provide qualitative support for our earlier conclusion that the growth of the black hole lags that of the host galaxy in these massive ultraluminous galaxies.

  5. Black Holes are neither Particle Accelerators nor Dark Matter Probes

    E-Print Network [OSTI]

    Sean T. McWilliams

    2012-12-06T23:59:59.000Z

    It has been suggested that maximally spinning black holes can serve as particle accelerators, reaching arbitrarily high center-of-mass energies. Despite several objections regarding the practical achievability of such high energies, and demonstrations past and present that such large energies could never reach a distant observer, interest in this problem has remained substantial. We show that, unfortunately, a maximally spinning black hole can never serve as a probe of high energy collisions, even in principle and despite the correctness of the original diverging energy calculation. Black holes can indeed facilitate dark matter annihilation, but the most energetic photons can carry little more than the rest energy of the dark matter particles to a distant observer, and those photons are actually generated relatively far from the black hole where relativistic effects are negligible. Therefore, any strong gravitational potential could probe dark matter equally well, and an appeal to black holes for facilitating such collisions is unnecessary.

  6. Implications of a viscosity bound on black hole accretion

    E-Print Network [OSTI]

    Aninda Sinha; Banibrata Mukhopadhyay

    2012-02-13T23:59:59.000Z

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

  7. Black Holes with Flavors of Quantum Hair?

    E-Print Network [OSTI]

    Gia Dvali

    2006-07-20T23:59:59.000Z

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

  8. New Coordinate Systems for Axisymmetric Black Hole Collisions

    E-Print Network [OSTI]

    P. Anninos; S. R. Brandt; P. Walker

    1997-12-10T23:59:59.000Z

    We describe a grid generation procedure designed to construct new classes of orthogonal coordinate systems for binary black hole spacetimes. The computed coordinates offer an alternative approach to current methods, in addition to providing a framework for potentially more stable and accurate evolutions of colliding black holes. As a particular example, we apply our procedure to generate appropriate numerical grids to evolve Misner's axisymmetric initial data set representing two equal mass black holes colliding head-on. These new results are compared with previously published calculations, and we find generally good agreement in both the waveform profiles and total radiated energies over the allowable range of separation parameters. Furthermore, because no specialized treatment of the coordinate singularities is required, these new grids are more easily extendible to unequal mass and spinning black hole collisions.

  9. Numerical investigation of the threshold for primordial black hole formation

    E-Print Network [OSTI]

    J. C. Niemeyer

    1998-06-02T23:59:59.000Z

    First results of a numerical investigation of primordial black hole formation in the radiation dominated phase of the Early Universe are presented. The simulations follow the gravitational collapse of three different families of high-amplitude density fluctuations imposed at the time of horizon crossing. The threshold for black hole formation, \\delta_{c} \\approx 0.7, is found to be nearly identical for all perturbation families if the control parameter, \\delta, is chosen as the total excess mass within the initial horizon volume. Furthermore, we demonstrate that the scaling of black hole mass with distance from the formation threshold, known to occur in near-critical gravitational collapse, applies to primordial black hole formation.

  10. Rotating Hayward's regular black hole as particle accelerator

    E-Print Network [OSTI]

    Muhammed Amir; Sushant G. Ghosh

    2015-06-10T23:59:59.000Z

    Recently, Ban\\~{a}dos, Silk and West (BSW) demonstrated that the extremal Kerr black hole can act as a particle accelerator with arbitrarily high center-of-mass energy ($E_{CM}$) when the collision takes place near the horizon. The rotating Hayward's regular black hole, apart from Mass ($M$) and angular momentum ($a$), has a new parameter $g$ ($g>0$ is a constant) that provides a deviation from the Kerr black hole. We demonstrate that for each $g$, with $M=1$, there exist critical $a_{E}$ and $r_{H}^{E}$, which corresponds to a regular extremal black hole with degenerate horizon, and $a_{E}$ decreases and $r_{H}^{E}$ increases with increase in $g$. While $aparticle accelerator and thus in turn may provide a suitable framework for Plank-scale physics. For a non-extremal case, there always exist a finite upper bound of $E_{CM}$, which increases with deviation parameter $g$.

  11. In Situ Causticizing for Black Liquor Gasification

    SciTech Connect (OSTI)

    Scott Alan Sinquefield

    2005-10-01T23:59:59.000Z

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

  12. Accounting for forest carbon pool dynamics in product carbon footprints: Challenges and opportunities

    SciTech Connect (OSTI)

    Newell, Joshua P., E-mail: jpnewell@umich.edu [School of Natural Resources and Environment, University of Michigan, Ann Arbor (United States); Vos, Robert O., E-mail: vos@usc.edu [Spatial Sciences Institute, University of Southern California (United States)

    2012-11-15T23:59:59.000Z

    Modification and loss of forests due to natural and anthropogenic disturbance contribute an estimated 20% of annual greenhouse gas (GHG) emissions worldwide. Although forest carbon pool modeling rarely suggests a 'carbon neutral' flux profile, the life cycle assessment community and associated product carbon footprint protocols have struggled to account for the GHG emissions associated with forestry, specifically, and land use generally. Principally, this is due to underdeveloped linkages between life cycle inventory (LCI) modeling for wood and forest carbon modeling for a full range of forest types and harvest practices, as well as a lack of transparency in globalized forest supply chains. In this paper, through a comparative study of U.S. and Chinese coated freesheet paper, we develop the initial foundations for a methodology that rescales IPCC methods from the national to the product level, with reference to the approaches in three international product carbon footprint protocols. Due to differences in geographic origin of the wood fiber, the results for two scenarios are highly divergent. This suggests that both wood LCI models and the protocols need further development to capture the range of spatial and temporal dimensions for supply chains (and the associated land use change and modification) for specific product systems. The paper concludes by outlining opportunities to measure and reduce uncertainty in accounting for net emissions of biogenic carbon from forestland, where timber is harvested for consumer products. - Highlights: Black-Right-Pointing-Pointer Typical life cycle assessment practice for consumer products often excludes significant land use change emissions when estimating carbon footprints. Black-Right-Pointing-Pointer The article provides a methodology to rescale IPCC guidelines for product-level carbon footprints. Black-Right-Pointing-Pointer Life cycle inventories and product carbon footprint protocols need more comprehensive land use-related accounting. Black-Right-Pointing-Pointer Interdisciplinary collaboration linking the LCA and forest carbon modeling communities is necessary.

  13. 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

  14. NUCLEOSYNTHETIC CONSTRAINTS ON THE MASS OF THE HEAVIEST SUPERNOVAE

    SciTech Connect (OSTI)

    Brown, Justin M.; Woosley, S. E., E-mail: jumbrown@ucsc.edu [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States)

    2013-06-01T23:59:59.000Z

    We explore the sensitivity of nucleosynthesis in massive stars to the truncation of supernova explosions above a certain mass. It is assumed that stars of all masses contribute to nucleosynthesis by their pre-explosive winds, but above a certain limiting main sequence mass, M{sub BH}, the presupernova star becomes a black hole and ejects nothing more. The solar abundances from oxygen to atomic mass 90 are fit quite well assuming no cutoff at all, i.e., by assuming all stars up to 120 M{sub Sun} make successful supernovae. Little degradation in the fit occurs if M{sub BH} is reduced to 25 M{sub Sun }. If this limit is reduced further however, the nucleosynthesis of the s-process declines precipitously and the production of species made in the winds, e.g., carbon, becomes unacceptably large compared with elements made in the explosion, e.g., silicon and oxygen. By varying uncertain physics, especially the mass loss rate for massive stars and the rate for the {sup 22}Ne({alpha}, n){sup 25}Mg reaction rate, acceptable nucleosynthesis might still be achieved with a cutoff as low as 18 M{sub Sun }. This would require, however, a supernova frequency three times greater than the fiducial value obtained when all stars explode in order to produce the required {sup 16}O. The effects of varying M{sub BH} on the nucleosynthesis of {sup 60}Fe and {sup 26}Al, the production of helium as measured by {Delta}Y/{Delta}Z, and the average masses of compact remnants are also examined.

  15. Gravitational radiation from dynamical black holes

    E-Print Network [OSTI]

    Sean A. Hayward

    2005-12-26T23:59:59.000Z

    An effective energy tensor for gravitational radiation is identified for uniformly expanding flows of the Hawking mass-energy. It appears in an energy conservation law expressing the change in mass due to the energy densities of matter and gravitational radiation, with respect to a Killing-like vector encoding a preferred flow of time outside a black hole. In a spin-coefficient formulation, the components of the effective energy tensor can be understood as the energy densities of ingoing and outgoing, transverse and longitudinal gravitational radiation. By anchoring the flow to the trapping horizon of a black hole in a given sequence of spatial hypersurfaces, there is a locally unique flow and a measure of gravitational radiation in the strong-field regime.

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

    E-Print Network [OSTI]

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

    2014-09-28T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    L. Arturo Urena-Lopez; Lizbeth M. Fernandez

    2011-07-15T23:59:59.000Z

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

  18. Higgs Boson Production from Black Holes at the LHC

    E-Print Network [OSTI]

    Gouranga C. Nayak; J. Smith

    2006-06-09T23:59:59.000Z

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

  19. 7, 605639, 2007 Mass, chemistry and

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    , and V. Gianelle 7 1 Institute for Environment and Sustainability, Joint Research Centre, European Commission, T.P. 290, Ispra (VA) 21020, Italy 2 British Geological Survey, Keyworth, Nottingham, NG12 5GG, UK particles", which accounts for >80% of fine par- ticles). Organic matter (OM) and black-carbon (BC

  20. Composite catalysts supported on modified carbon substrates and methods of making the same

    DOE Patents [OSTI]

    Popov, Branko N. (Columbia, SC); Subramanian, Nalini (Kennesaw, GA); Colon-Mercado, Hector R. (Columbia, SC)

    2009-11-17T23:59:59.000Z

    A method of producing a composite carbon catalyst is generally disclosed. The method includes oxidizing a carbon precursor (e.g., carbon black). Optionally, nitrogen functional groups can be added to the oxidized carbon precursor. Then, the oxidized carbon precursor is refluxed with a non-platinum transitional metal precursor in a solution. Finally, the solution is pyrolyzed at a temperature of at least about 500.degree. C.

  1. Supporting Information Enhanced Activated Carbon Cathode Performance for Microbial Fuel

    E-Print Network [OSTI]

    S1 Supporting Information Enhanced Activated Carbon Cathode Performance for Microbial Fuel Cell by Blending Carbon Black Xiaoyuan Zhang 1 , Xue Xia 2 , Ivan Ivanov 1 , Xia Huang 2 , Bruce E. Logan *1 1, School of Environment, Tsinghua University, Beijing 100084, P.R.China *Corresponding Author: Phone: (1

  2. On Noncommutative Black Holes Thermodynamics

    E-Print Network [OSTI]

    Faizal, Mir; Ulhoa, S C

    2015-01-01T23:59:59.000Z

    In this paper, we will analyze noncommutative deformation of the Schwarzschild black holes and Kerr black holes. We will perform our analysis by relating the commutative and the noncommutative metrics using an Moyal product. We will also analyze the thermodynamics of these noncommutative black hole solutions. We will explicitly derive expression for the corrected entropy and temperature of these black hole solutions.

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

    E-Print Network [OSTI]

    Stephanne Taylor; Eric Poisson

    2008-09-11T23:59:59.000Z

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

  4. Moduli vacuum bubbles produced by evaporating black holes

    SciTech Connect (OSTI)

    Morris, J. R. [Physics Department, Indiana University Northwest, 3400 Broadway, Gary, Indiana 46408 (United States)

    2007-10-15T23:59:59.000Z

    We consider a model with a toroidally compactified extra dimension giving rise to a temperature-dependent 4D effective potential with one-loop contributions due to the Casimir effect, along with a 5D cosmological constant. The forms of the effective potential at low and high temperatures indicate a possibility for the formation of a domain wall bubble, formed by the modulus scalar field, surrounding an evaporating black hole. This is viewed as an example of a recently proposed black hole vacuum bubble arising from matter-sourced moduli fields in the vicinity of an evaporating black hole [D. Green, E. Silverstein, and D. Starr, Phys. Rev. D 74, 024004 (2006)]. The black hole bubble can be highly opaque to lower-energy particles and photons, and thereby entrap them within. For high-temperature black holes, there may also be a symmetry-breaking black hole bubble of false vacuum of the type previously conjectured by Moss [I. G. Moss, Phys. Rev. D 32, 1333 (1985)], tending to reflect low-energy particles from its wall. A double bubble composed of these two different types of bubble may form around the black hole, altering the hole's emission spectrum that reaches outside observers. Smaller mass black holes that have already evaporated away could have left vacuum bubbles behind that contribute to the dark matter.

  5. Analysis of spherically symmetric black holes in Braneworld models

    E-Print Network [OSTI]

    A. B. Pavan

    2010-05-25T23:59:59.000Z

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

  6. Energy input from quasars regulates the growth and activity of black holes and their host galaxies

    E-Print Network [OSTI]

    Tiziana Di Matteo; Volker Springel; Lars Hernquist

    2005-02-09T23:59:59.000Z

    In the early Universe, while galaxies were still forming, black holes as massive as a billion solar masses powered quasars. Supermassive black holes are found at the centers of most galaxies today, where their masses are related to the velocity dispersions of stars in their host galaxies and hence to the mass of the central bulge of the galaxy. This suggests a link between the growth of the black holes and the host galaxies, which has indeed been assumed for a number of years. But the origin of the observed relation between black hole mass and stellar velocity dispersion, and its connection with the evolution of galaxies have remained unclear. Here we report simulations that simultaneously follow star formation and the growth of black holes during galaxy-galaxy collisions. We find that in addition to generating a burst of star formation, a merger leads to strong inflows that feed gas to the supermassive black hole and thereby power the quasar. The energy released by the quasar expels enough gas to quench both star formation and further black hole growth. This determines the lifetime of the quasar phase (approaching 100 million years) and explains the relationship between the black hole mass and the stellar velocity dispersion.

  7. On the Neutron Star-Black Hole Binaries Produced by Binary-driven Hypernovae

    E-Print Network [OSTI]

    Fryer, C L; Rueda, J A; Ruffini, R

    2015-01-01T23:59:59.000Z

    Binary-driven hypernovae (BdHNe) following the induced gravitational collapse (IGC) paradigm have been introduced to explain the concomitance of energetic long gamma-ray bursts (GRBs) with type Ic supernovae. The progenitor system is a tight binary system composed of a carbon-oxygen (CO) core and a neutron star (NS) companion. The supernova ejecta of the exploding CO core triggers a hypercritical accretion process onto the NS, which in a few seconds reach the NS critical mass, and gravitationally collapses to a black hole (BH) emitting a GRB. These tight binary systems evolve through the supernova explosion very differently than compact binary progenitors studied in population synthesis calculations. First, the hypercritical accretion onto the NS companion alters both the mass and momentum of the binary. Second, because the explosion timescale is on par with the orbital period, the mass ejection can not be assumed to be instantaneous. Finally, the bow shock created as the accreting NS plows through the supern...

  8. Gravitating discs around black holes

    E-Print Network [OSTI]

    V. Karas; J. -M. Hure; O. Semerak

    2004-01-16T23:59:59.000Z

    Fluid discs and tori around black holes are discussed within different approaches and with the emphasis on the role of disc gravity. First reviewed are the prospects of investigating the gravitational field of a black hole--disc system by analytical solutions of stationary, axially symmetric Einstein's equations. Then, more detailed considerations are focused to middle and outer parts of extended disc-like configurations where relativistic effects are small and the Newtonian description is adequate. Within general relativity, only a static case has been analysed in detail. Results are often very inspiring, however, simplifying assumptions must be imposed: ad hoc profiles of the disc density are commonly assumed and the effects of frame-dragging and completely lacking. Astrophysical discs (e.g. accretion discs in active galactic nuclei) typically extend far beyond the relativistic domain and are fairly diluted. However, self-gravity is still essential for their structure and evolution, as well as for their radiation emission and the impact on the environment around. For example, a nuclear star cluster in a galactic centre may bear various imprints of mutual star--disc interactions, which can be recognised in observational properties, such as the relation between the central mass and stellar velocity dispersion.

  9. Optical Sensing of Ecosystem Carbon Fluxes

    E-Print Network [OSTI]

    . Solar Induced Fluorescence (peaks at 690 and 735 nm) #12;GEP = ! fAPAR PARin Where: GEP is the gross and absorbed carbon - In existing models ! is assigned a maximum value based on cover type and downregulated Calibration panel AMSPEC FUSION #12;SK-Old Aspen Seasonality: NDVI, EVI, GEP Data from T. Hilker, T.A. Black

  10. Generalized uncertainty principle and black hole thermodynamics

    E-Print Network [OSTI]

    Sunandan Gangopadhyay; Abhijit Dutta; Anirban Saha

    2014-01-08T23:59:59.000Z

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

  11. Preparation of highly loaded Pt/carbon xerogel catalysts for Proton Exchange Membrane fuel cells by the Strong Electrostatic Adsorption method

    E-Print Network [OSTI]

    Regalbuto, John R.

    and composition, such as carbon xerogels and aerogels, constitute an interesting alternative to carbon blacks [4, the samples were filtered, dried and reduced. In order to increase the Pt weight percentage, up to three

  12. Phnomnes de pizoconductivit dans les composites polymre-noir de carbone. Application aux capteurs

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    régulation du trafic routier est envisagé. Abstract. - The electrical conductivity of some carbon black-polymer347 Phénomčnes de piézoconductivité dans les composites polymčre-noir de carbone. Application aux) Résumé. - Certains composites polymčre-noir de carbone ont une conductivité qui varie beaucoup avec les

  13. Fuel moisture influences on fire-altered carbon in masticated fuels: An experimental study

    E-Print Network [OSTI]

    ] Biomass burning is a significant contributor to atmospheric carbon emissions but may also provide mastication (mechanical forest thinning) and fire convert biomass to black carbon is essential moisture and its role in dictating both the quantity and quality of the carbon produced in masticated fuel

  14. Helical superconducting black holes

    E-Print Network [OSTI]

    Aristomenis Donos; Jerome P. Gauntlett

    2012-05-17T23:59:59.000Z

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

  15. Search for gravitational waves from binary black hole inspiral, merger and ringdown

    E-Print Network [OSTI]

    The LIGO Scientific Collaboration; the Virgo Collaboration; J. Abadie; B. P. Abbott; R. Abbott; M. Abernathy; T. Accadia; F. Acernese; C. Adams; R. Adhikari; P. Ajith; B. Allen; G. S. Allen; E. Amador Ceron; R. S. Amin; S. B. Anderson; W. G. Anderson; F. Antonucci; M. A. Arain; M. C. Araya; M. Aronsson; Y. Aso; S. M. Aston; P. Astone; D. Atkinson; P. Aufmuth; C. Aulbert; S. Babak; P. Baker; G. Ballardin; T. Ballinger; S. Ballmer; D. Barker; S. Barnum; F. Barone; B. Barr; P. Barriga; L. Barsotti; M. Barsuglia; M. A. Barton; I. Bartos; R. Bassiri; M. Bastarrika; J. Bauchrowitz; Th. S. Bauer; B. Behnke; M. G. Beker; A. Belletoile; M. Benacquista; A. Bertolini; J. Betzwieser; N. Beveridge; P. T. Beyersdorf; I. A. Bilenko; G. Billingsley; J. Birch; S. Birindelli; R. Biswas; M. Bitossi; M. A. Bizouard; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; B. Bland; M. Blom; C. Boccara; O. Bock; T. P. Bodiya; R. Bondarescu; F. Bondu; L. Bonelli; R. Bonnand; R. Bork; M. Born; V. Boschi; S. Bose; L. Bosi; B. Bouhou; M. Boyle; S. Braccini; C. Bradaschia; P. R. Brady; V. B. Braginsky; J. E. Brau; J. Breyer; D. O. Bridges; A. Brillet; M. Brinkmann; V. Brisson; M. Britzger; A. F. Brooks; D. A. Brown; R. Budzy?ski; T. Bulik; H. J. Bulten; A. Buonanno; J. Burguet-Castell; O. Burmeister; D. Buskulic; C. Buy; R. L. Byer; L. Cadonati; G. Cagnoli; J. Cain; E. Calloni; J. B. Camp; E. Campagna; P. Campsie; J. Cannizzo; K. Cannon; B. Canuel; J. Cao; C. Capano; F. Carbognani; S. Caride; S. Caudill; M. Cavaglia`; F. Cavalier; R. Cavalieri; G. Cella; C. Cepeda; E. Cesarini; O. Chaibi; T. Chalermsongsak; E. Chalkley; P. Charlton; E. Chassande-Mottin; S. Chelkowski; Y. Chen; A. Chincarini; N. Christensen; S. S. Y. Chua; C. T. Y. Chung; D. Clark; J. Clark; J. H. Clayton; F. Cleva; E. Coccia; C. N. Colacino; J. Colas; A. Colla; M. Colombini; R. Conte; D. Cook; T. R. Corbitt; N. Cornish; A. Corsi; C. A. Costa; J. -P. Coulon; D. M. Coward; D. C. Coyne; J. D. E. Creighton; T. D. Creighton; A. M. Cruise; R. M. Culter; A. Cumming; L. Cunningham; E. Cuoco; K. Dahl; S. L. Danilishin; R. Dannenberg; S. D'Antonio; K. Danzmann; K. Das; V. Dattilo; B. Daudert; M. Davier; G. Davies; A. Davis; E. J. Daw; R. Day; T. Dayanga; R. De Rosa; D. DeBra; G. Debreczeni; J. Degallaix; M. del Prete; V. Dergachev; R. DeRosa; R. DeSalvo; P. Devanka; S. Dhurandhar; L. Di Fiore; A. Di Lieto; I. Di Palma; M. Di Paolo Emilio; A. Di Virgilio; M. Díaz; A. Dietz; F. Donovan; K. L. Dooley; E. E. Doomes; S. Dorsher; E. S. D. Douglas; M. Drago; R. W. P. Drever; J. C. Driggers; J. Dueck; J. -C. Dumas; T. Eberle; M. Edgar; M. Edwards; A. Effler; P. Ehrens; G. Ely; R. Engel; T. Etzel; M. Evans; T. Evans; V. Fafone; S. Fairhurst; Y. Fan; B. F. Farr; D. Fazi; H. Fehrmann; D. Feldbaum; I. Ferrante; F. Fidecaro; L. S. Finn; I. Fiori; R. Flaminio; M. Flanigan; K. Flasch; S. Foley; C. Forrest; E. Forsi; L. A. Forte; N. Fotopoulos; J. -D. Fournier; J. Franc; S. Frasca; F. Frasconi; M. Frede; M. Frei; Z. Frei; A. Freise; R. Frey; T. T. Fricke; D. Friedrich; P. Fritschel; V. V. Frolov; P. Fulda; M. Fyffe; M. Galimberti; L. Gammaitoni; J. A. Garofoli; F. Garufi; M. E. Gáspár; G. Gemme; E. Genin; A. Gennai; I. Gholami; S. Ghosh; J. A. Giaime; S. Giampanis; K. D. Giardina; A. Giazotto; C. Gill; E. Goetz; L. M. Goggin; G. González; M. L. Gorodetsky; S. Goßler; R. Gouaty; C. Graef; M. Granata; A. Grant; S. Gras; C. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; C. Greverie; R. Grosso; H. Grote; S. Grunewald; G. M. Guidi; E. K. Gustafson; R. Gustafson; B. Hage; P. Hall; J. M. Hallam; D. Hammer; G. Hammond; J. Hanks; C. Hanna; J. Hanson; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; K. Haughian; K. Hayama; J. -F. Hayau; T. Hayler; J. Heefner; H. Heitmann; P. Hello; I. S. Heng; A. W. Heptonstall; M. Hewitson; S. Hild; E. Hirose; D. Hoak; K. A. Hodge; K. Holt; D. J. Hosken; J. Hough; E. J. Howell; D. Hoyland; D. Huet; B. Hughey; S. Husa; S. H. Huttner; T. Huynh-Dinh; D. R. Ingram; R. Inta; T. Isogai; A. Ivanov; P. Jaranowski; W. W. Johnson; D. I. Jones; G. Jones; R. Jones; L. Ju; P. Kalmus; V. Kalogera; S. Kandhasamy; J. B. Kanner; E. Katsavounidis; K. Kawabe; S. Kawamura; F. Kawazoe; W. Kells; D. G. Keppel; A. Khalaidovski; F. Y. Khalili; E. A. Khazanov; H. Kim; P. J. King; D. L. Kinzel; J. S. Kissel; S. Klimenko; V. Kondrashov; R. Kopparapu; S. Koranda; I. Kowalska; D. Kozak; T. Krause; V. Kringel; S. Krishnamurthy; B. Krishnan; A. Królak; G. Kuehn; J. Kullman; R. Kumar; P. Kwee; M. Landry; M. Lang; B. Lantz; N. Lastzka; A. Lazzarini; P. Leaci; J. Leong; I. Leonor; N. Leroy; N. Letendre; J. Li; T. G. F. Li; N. Liguori; H. Lin; P. E. Lindquist; N. A. Lockerbie; D. Lodhia; M. Lorenzini; V. Loriette; M. Lormand; G. Losurdo; P. Lu; J. Luan; M. Lubinski; A. Lucianetti; H. Lück; A. D. Lundgren; B. Machenschalk; M. MacInnis; M. Mageswaran; K. Mailand; E. Majorana

    2011-02-18T23:59:59.000Z

    We present the first modeled search for gravitational waves using the complete binary black hole gravitational waveform from inspiral through the merger and ringdown for binaries with negligible component spin. We searched approximately 2 years of LIGO data taken between November 2005 and September 2007 for systems with component masses of 1-99 solar masses and total masses of 25-100 solar masses. We did not detect any plausible gravitational-wave signals but we do place upper limits on the merger rate of binary black holes as a function of the component masses in this range. We constrain the rate of mergers for binary black hole systems with component masses between 19 and 28 solar masses and negligible spin to be no more than 2.0 per Mpc^3 per Myr at 90% confidence.

  16. Extremely stable Nafion based carbon monoxide sensor

    SciTech Connect (OSTI)

    van der Wal; P.D. de Rooij, N.F.; Koudelka-Hep, M. [Univ. of Neuchatel (Switzerland)

    1996-12-31T23:59:59.000Z

    At present carbon monoxide sensing devices are readily available for many industrial applications. The sensors used in these devices include electrochemical sensors, semiconductor sensors, calorimetric detectors and infra red detectors. From these devices the electrochemical sensors are of specific interest because of their high selectivity and low power consumption. This makes them suitable for use in battery operated devices, e.g. for domestic safety. However, their relatively high price and frequent need for recalibration seriously hamper their utilisation on a large scale. The relatively high price of electrochemical CO sensors is caused by the complexity of fabrication. They are composed of a cylindrical housing, with one end the counter and reference electrodes, and on the other the working electrode. The electrodes are made out of Teflon bonded platinum black on a Teflon substrate and the electrolyte is a sulfuric acid solution. The aim of this work was to develop electrochemical CO sensors, that are small and cheaper than the existing products. The approach concentrated on three main aspects: (a) simplification of the device assembly by investigating the of using a planar sensor design, (b) use of mass production compatible fabrication, and (c) replacement of the sulfuric acid.

  17. Limits on New Physics from Black Holes

    E-Print Network [OSTI]

    Clifford Cheung; Stefan Leichenauer

    2014-08-02T23:59:59.000Z

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

  18. Black hole formation in the early universe

    E-Print Network [OSTI]

    Latif, M A; Schmidt, W; Niemeyer, J

    2013-01-01T23:59:59.000Z

    Supermassive black holes with up to a $\\rm 10^{9}~M_{\\odot}$ dwell in the centers of present-day galaxies, and their presence has been confirmed at z $\\geq$ 6. Their formation at such early epochs is still an enigma. Different pathways have been suggested to assemble supermassive black holes in the first billion years after the Big Bang. Direct collapse has emerged as a highly plausible scenario to form black holes as it provides seed masses of $\\rm 10^{5}-10^{6}~M_{\\odot}$. Gravitational collapse in atomic cooling haloes with virial temperatures T$_{vir} \\geq 10^{4}$~K may lead to the formation of massive seed black holes in the presence of an intense background UV flux. Turbulence plays a central role in regulating accretion and transporting angular momentum. We present here the highest resolution cosmological large-eddy simulations to date which track the evolution of high-density regions on scales of $0.25$~AU beyond the formation of the first peak, and study the impact of subgrid-scale turbulence. The pe...

  19. Supermassive black holes from OASIS and SAURON integral-field kinematics

    E-Print Network [OSTI]

    M. Cappellari; R. Bacon; R. L. Davies; P. T. de Zeeuw; E. Emsellem; J. Falcon-Barroso; D. Krajnovic; H. Kuntschner; R. M. McDermid; R. F. Peletier; M. Sarzi; R. C. E. van den Bosch; G. van de Ven

    2007-09-18T23:59:59.000Z

    Supermassive black holes are a key element in our understanding of how galaxies form. Most of the progress in this very active field of research is based on just ~30 determinations of black hole mass, accumulated over the past decade. We illustrate how integral-field spectroscopy, and in particular our OASIS modeling effort, can help improve the current situation.

  20. Supermassive black holes from OASIS and SAURON integral-field kinematics

    E-Print Network [OSTI]

    Cappellari, M; Davies, R L; De Zeeuw, P T; Emsellem, E; Falcon-Barroso, J; Krajnovic, D; Kuntschner, H; McDermid, R M; Peletier, R F; Sarzi, M; Bosch, R C E van den; van de Ven, G

    2007-01-01T23:59:59.000Z

    Supermassive black holes are a key element in our understanding of how galaxies form. Most of the progress in this very active field of research is based on just ~30 determinations of black hole mass, accumulated over the past decade. We illustrate how integral-field spectroscopy, and in particular our OASIS modeling effort, can help improve the current situation.

  1. Probing the Spacetime Around Supermassive Black Holes with Ejected Plasma Blobs

    E-Print Network [OSTI]

    Christian, Pierre

    2015-01-01T23:59:59.000Z

    Millimeter-wavelength VLBI observations of the supermassive black holes in Sgr A* and M87 by the Event Horizon Telescope could potentially trace the dynamics of ejected plasma blobs in real time. We demonstrate that the trajectory and tidal stretching of these blobs can be used to test general relativity and set new constraints on the mass and spin of these black holes.

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

    E-Print Network [OSTI]

    Ichiro Oda

    2015-03-18T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Oda, Ichiro

    2015-01-01T23:59:59.000Z

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

  4. A DETERMINATION OF THE SPIN OF THE BLACK HOLE PRIMARY IN LMC X-1

    E-Print Network [OSTI]

    Gou, Lijun

    The first extragalactic X-ray binary, LMC X-1, was discovered in 1969. In the 1980s, its compact primary was established as the fourth dynamical black hole candidate. Recently, we published accurate values for the mass of ...

  5. THE EXTREME SPIN OF THE BLACK HOLE IN CYGNUS X-1

    E-Print Network [OSTI]

    Gou, Lijun

    The compact primary in the X-ray binary Cygnus X-1 was the first black hole to be established via dynamical observations. We have recently determined accurate values for its mass and distance, and for the orbital inclination ...

  6. The Fundamental Plane of Black Hole Activity in the Optical Band

    E-Print Network [OSTI]

    Saikia, Payaswini; Falcke, Heino

    2015-01-01T23:59:59.000Z

    Black hole accretion and jet formation have long been thought to be scale invariant. One empirical relation suggesting scale invariance is the Fundamental Plane of Black Hole activity, which is a plane in the space given by black hole mass and the radio/X-ray luminosities. We search for an alternative version of this plane using the luminosity of [OIII] emission line instead of X-ray luminosity. We use a complete sample of 39 supermassive black holes selected from the Palomar Spectroscopic Survey with available radio and optical measurements and information on black hole mass. A sample of stellar mass X-ray binaries has also been included to examine if physical processes behind accretion is universal across the entire range of black hole mass. We present the results of multivariate regression analysis performed on the AGN sample and show that the sample stretches out as a plane in the 3D logarithmic space created by bolometric luminosity, radio luminosity and black hole mass. We reproduce the established Fund...

  7. Giant black hole ringings induced by massive gravity

    E-Print Network [OSTI]

    Yves Decanini; Antoine Folacci; Mohamed Ould El Hadj

    2014-01-01T23:59:59.000Z

    A distorted black hole radiates gravitational waves in order to settle down in one of the geometries permitted by the no-hair theorem. During that relaxation phase, a characteristic damped ringing is generated. It can be theoretically constructed from the black hole quasinormal frequencies (which govern its oscillating behavior and its decay) and from the associated excitation factors (which determine intrinsically its amplitude) by carefully taking into account the source of the distortion. Here, by considering the Schwarzschild black hole in the framework of massive gravity, we show that the excitation factors have an unexpected strong resonant behavior leading to giant ringings which are, moreover, slowly decaying. Such extraordinary black hole ringings could be observed by the next generations of gravitational wave detectors and allow us to test the various massive gravity theories or their absence could be used to impose strong constraints on the graviton mass.

  8. Lovelock black holes in a string cloud background

    E-Print Network [OSTI]

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

    2015-06-11T23:59:59.000Z

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

  9. Failed supernovae explain the compact remnant mass function

    SciTech Connect (OSTI)

    Kochanek, C. S. [Department of Astronomy, The Ohio State University, 140 West 18th Avenue, Columbus, OH 43210, USAAND (United States); Center for Cosmology and AstroParticle Physics, The Ohio State University, 191 W. Woodruff Avenue, Columbus, OH 43210 (United States)

    2014-04-10T23:59:59.000Z

    One explanation for the absence of higher mass red supergiants (16.5 M {sub ?} ? M ? 25 M {sub ?}) as the progenitors of Type IIP supernovae (SNe) is that they die in failed SNe creating black holes. Simulations show that such failed SNe still eject their hydrogen envelopes in a weak transient, leaving a black hole with the mass of the star's helium core (5-8 M {sub ?}). Here we show that this naturally explains the typical masses of observed black holes and the gap between neutron star and black hole masses without any fine-tuning of stellar mass loss, binary mass transfer, or the SN mechanism, beyond having it fail in a mass range where many progenitor models have density structures that make the explosions more likely to fail. There is no difficulty including this ?20% population of failed SNe in any accounting of SN types over the progenitor mass function. And, other than patience, there is no observational barrier to either detecting these black hole formation events or limiting their rates to be well below this prediction.

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

    E-Print Network [OSTI]

    Asimina Arvanitaki; Masha Baryakhtar; Xinlu Huang

    2015-03-23T23:59:59.000Z

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

  11. Formation and Evolution of Galactic Black Holes

    E-Print Network [OSTI]

    F. Combes

    2002-08-06T23:59:59.000Z

    The main requirements for fueling an active galactic nucleus and to form massive black holes are reviewed. Low-luminosity AGN can be fueled easily from the local star clusters, near the nucleus, and the various stellar processes are described. Above a certain luminosity (and therefore accretion rate) large-scale gas flows from galactic scales are required. These can be driven by gravity torques of non-axisymmetric perturbations, such as bars, spirals, galaxy interactions. Observational evidence that these mechanisms are in action is found for high enough luminosities. It is very frequent that starbursts are also triggered through the same mechanisms, and the dense nuclear star clusters formed provide fuel for the AGN over a longer time-scale. Secular internal evolution and more violent evolution through interactions and mergers contribute to grow both a massive black hole and a bulge, and this could explain the observed proportionality relation between the mass of these two components.

  12. Black Bean Orange Salad Ingredients

    E-Print Network [OSTI]

    Liskiewicz, Maciej

    beans in a colander under running water to remove sodium. Allow to drain. 2. Cut the ends offBlack Bean Orange Salad Ingredients: 15 ounces black beans, canned, drained and rinsed 1/4 red

  13. Gasification of black liquor

    SciTech Connect (OSTI)

    Kohl, A.L.

    1987-07-28T23:59:59.000Z

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

  14. Simulations of binary black hole mergers using spectral methods

    SciTech Connect (OSTI)

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

    2009-12-15T23:59:59.000Z

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

  15. Towards noncommutative quantum black holes

    SciTech Connect (OSTI)

    Lopez-Dominguez, J. C.; Obregon, O.; Sabido, M.; Ramirez, C. [Instituto de Fisica de la Universidad de Guanajuato, P.O. Box E-143, 37150 Leon Gto. (Mexico); Facultad de Ciencias Fisico Matematicas, Universidad Autonoma de Puebla, P.O. Box 1364, 72000 Puebla (Mexico)

    2006-10-15T23:59:59.000Z

    In this paper we study noncommutative black holes. We use a diffeomorphism between the Schwarzschild black hole and the Kantowski-Sachs cosmological model, which is generalized to noncommutative minisuperspace. Through the use of the Feynman-Hibbs procedure we are able to study the thermodynamics of the black hole, in particular, we calculate the Hawking's temperature and entropy for the noncommutative Schwarzschild black hole.

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

    SciTech Connect (OSTI)

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

    2005-07-15T23:59:59.000Z

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

  17. 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.

    1994-01-01T23:59:59.000Z

    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 ...

  18. Ecosystem carbon dioxide fluxes after disturbance in forests of North America

    E-Print Network [OSTI]

    2010-01-01T23:59:59.000Z

    10.1029/2010JG001390, 2010 Ecosystem carbon dioxide fluxesdioxide fluxes of black spruce ecosystems in eastern Northof a stand?replacing fire on ecosystem CO 2 exchange of a

  19. Towards an understanding of the carbon isotopic changes across the Toarcian oceanic anoxic event

    E-Print Network [OSTI]

    Cohen, Alison Margaret

    2005-01-01T23:59:59.000Z

    A combination of bulk carbon, biomarker and compound specific isotopic analyses were used in order to investigate the changes which accompanied the deposition of black shales during the upper tenuicostatum and lower ...

  20. Combustion of black liquor

    SciTech Connect (OSTI)

    Mullen, W.T.

    1989-08-15T23:59:59.000Z

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

  1. Gasification of black liquor

    DOE Patents [OSTI]

    Kohl, Arthur L. (Woodland Hills, CA)

    1987-07-28T23:59:59.000Z

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

  2. Gasification of black liquor

    DOE Patents [OSTI]

    Kohl, A.L.

    1987-07-28T23:59:59.000Z

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

  3. Quantum black hole inflation

    E-Print Network [OSTI]

    M. B. Altaie

    2001-05-07T23:59:59.000Z

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

  4. Black Holes at Accelerators

    E-Print Network [OSTI]

    Bryan Webber

    2006-04-06T23:59:59.000Z

    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.

  5. Supermassive Black Hole Growth and Merger Rates from Cosmological N-body Simulations

    E-Print Network [OSTI]

    Miroslav Micic; Kelly Holley-Bockelmann; Steinn Sigurdsson; Tom Abel

    2007-03-20T23:59:59.000Z

    Understanding how seed black holes grow into intermediate and supermassive black holes (IMBHs and SMBHs, respectively) has important implications for the duty-cycle of active galactic nuclei (AGN), galaxy evolution, and gravitational wave astronomy. Most studies of the cosmological growth and merger history of black holes have used semianalytic models and have concentrated on SMBH growth in luminous galaxies. Using high resolution cosmological N-body simulations, we track the assembly of black holes over a large range of final masses -- from seed black holes to SMBHs -- over widely varying dynamical histories. We used the dynamics of dark matter halos to track the evolution of seed black holes in three different gas accretion scenarios. We have found that growth of Sagittarius A* - size SMBH reaches its maximum mass M_{SMBH}~10^6Msun at z~6 through early gaseous accretion episodes, after which it stays at near constant mass. At the same redshift, the duty-cycle of the host AGN ends, hence redshift z=6 marks the transition from an AGN to a starburst galaxy which eventually becomes the Milky Way. By tracking black hole growth as a function of time and mass, we estimate that the IMBH merger rate reaches a maximum of R_{max}=55 yr^-1 at z=11. From IMBH merger rates we calculate N_{ULX}=7 per Milky Way type galaxy per redshift in redshift range 2

  6. Cauchy horizon singularity without mass inflation

    E-Print Network [OSTI]

    P. R. Brady; D. Nunez; S. Sinha

    1992-11-20T23:59:59.000Z

    A perturbed Reissner-Nordstr\\"om-de Sitter solution is used to emphasize the nature of the singularity along the Cauchy horizon of a charged spherically symmetric black hole. For these solutions, conditions may prevail under which the mass function is bounded and yet the curvature scalar $R_{\\alpha\\beta\\gamma\\delta} R^{\\alpha\\beta\\gamma\\delta}$ diverges.

  7. Low temperature pyrolysis of black liquor and polymerization of products in alkali aqueous medium

    SciTech Connect (OSTI)

    Demirbas, A. (Dept. of Chemical Education, Karadeniz Teknik Univ., Trabzon (TR)); Ucan, H. (Dept. of Chemistry, Selcuk Univ., Konya (TR))

    1991-01-01T23:59:59.000Z

    Atmospheric pressure pyrolysis for the production of liquids and gases from black liquor and its calcium salts and acidic precipitate have been carried out in a little stainless steel tube. Yields, sum of liquid and gas products, from black liquor and its calcium salts and acidic precipitate were 44.7%, 52.0% and 59.1% of dry basis respectively. The precipitates obtained from black liquor by acidifying with hydrochloric acid and passing carbon dioxide have been polymerized in aqueous acetone containing formaldehyde and ammonia, and converted a polymeric resin.

  8. BLACK HOLE AURORA POWERED BY A ROTATING BLACK HOLE

    SciTech Connect (OSTI)

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

    2010-05-15T23:59:59.000Z

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

  9. Simulating merging binary black holes with nearly extremal spins

    SciTech Connect (OSTI)

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

    2011-01-15T23:59:59.000Z

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

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

    E-Print Network [OSTI]

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

    2012-11-02T23:59:59.000Z

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

  11. Neutrino Masses

    E-Print Network [OSTI]

    Christian Weinheimer; Kai Zuber

    2013-09-04T23:59:59.000Z

    The various experiments on neutrino oscillation evidenced that neutrinos have indeed non-zero masses but cannot tell us the absolute neutrino mass scale. This scale of neutrino masses is very important for understanding the evolution and the structure formation of the universe as well as for nuclear and particle physics beyond the present Standard Model. Complementary to deducing constraints on the sum of all neutrino masses from cosmological observations two different methods to determine the neutrino mass scale in the laboratory are pursued: the search for neutrinoless double $\\beta$-decay and the direct neutrino mass search by investigating single $\\beta$-decays or electron captures. The former method is not only sensitive to neutrino masses but also probes the Majorana character of neutrinos and thus lepton number violation with high sensitivity. Currently quite a few experiments with different techniques are being constructed, commissioned or are even running, which aim for a sensitivity on the neutrino mass of {\\cal O}(100) meV. The principle methods and these experiments will be discussed in this short review.

  12. Nanoscale mass conveyors

    DOE Patents [OSTI]

    Regan, Brian C. (Oakland, CA); Aloni, Shaul (Albany, CA); Zettl, Alexander K. (Kensington, CA)

    2008-03-11T23:59:59.000Z

    A mass transport method and device for individually delivering chargeable atoms or molecules from source particles is disclosed. It comprises a channel; at least one source particle of chargeable material fixed to the surface of the channel at a position along its length; a means of heating the channel; and a means for applying an controllable electric field along the channel, whereby the device transports the atoms or molecules along the channel in response to applied electric field. In a preferred embodiment, the mass transport device will comprise a multiwalled carbon nanotube (MWNT), although other one dimensional structures may also be used. The MWNT or other structure acts as a channel for individual or small collections of atoms due to the atomic smoothness of the material. Also preferred is a source particle of a metal such as indium. The particles move by dissociation into small units, in some cases, individual atoms. The particles are preferably less than 100 nm in size.

  13. Carbon Fiber

    ScienceCinema (OSTI)

    McGetrick, Lee

    2014-07-23T23:59:59.000Z

    Lee McGetrick leads ORNL's effort to produce light, durable carbon fiber at lower cost -- a key to improvements in manufacturing that will produce more fuel-efficient vehicles and other advances.

  14. Carbon Sequestration

    SciTech Connect (OSTI)

    None

    2013-05-06T23:59:59.000Z

    Carbon Sequestration- the process of capturing the CO2 released by the burning of fossil fuels and storing it deep withing the Earth, trapped by a non-porous layer of rock.

  15. Carbon Fiber

    SciTech Connect (OSTI)

    McGetrick, Lee

    2014-04-17T23:59:59.000Z

    Lee McGetrick leads ORNL's effort to produce light, durable carbon fiber at lower cost -- a key to improvements in manufacturing that will produce more fuel-efficient vehicles and other advances.

  16. Noncommutative Inspired Black Holes in Extra Dimensions

    SciTech Connect (OSTI)

    Rizzo, Thomas G.

    2006-06-07T23:59:59.000Z

    In a recent string theory motivated paper, Nicolini, Smailagic and Spallucci (NSS) presented an interesting model for a noncommutative inspired, Schwarzschild-like black hole solution in 4-dimensions. The essential effect of having noncommutative co-ordinates in this approach is to smear out matter distributions on a scale associated with the turn-on of noncommutativity which was taken to be near the 4-d Planck mass. In particular, NSS assumed that this smearing was essentially Gaussian. This energy scale is sufficiently large that in 4-d such effects may remain invisible indefinitely. Extra dimensional models which attempt to address the gauge hierarchy problem, however, allow for the possibility that the effective fundamental scale may not be far from {approx} 1 TeV, an energy regime that will soon be probed by experiments at both the LHC and ILC. In this paper we generalize the NSS model to the case where flat, toroidally compactified extra dimensions are accessible at the TeV-scale and examine the resulting modifications in black hole properties due to the existence of noncommutativity. We show that while many of the noncommutativity-induced black hole features found in 4-d by NSS persist, in some cases there can be significant modifications due the presence of extra dimensions. We also demonstrate that the essential features of this approach are not particularly sensitive to the Gaussian nature of the smearing assumed by NSS.

  17. Kerr black holes with scalar hair

    E-Print Network [OSTI]

    Herdeiro, Carlos A R

    2014-01-01T23:59:59.000Z

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

  18. Supermassive Black Holes as Giant Bose-Einstein Condensates

    E-Print Network [OSTI]

    Theo M. Nieuwenhuizen

    2008-07-02T23:59:59.000Z

    The Schwarzschild metric has a divergent energy density at the horizon, which motivates a new approach to black holes. If matter is spread uniformly throughout the interior of a supermassive black hole, with mass $M\\sim M_\\star= 2.34 10^8M_\\odot$, it may arise from a Bose-Einstein condensate of densely packed H-atoms. Within the Relativistic Theory of Gravitation with a positive cosmological constant, a bosonic quantum field is coupled to the curvature scalar. In the Bose-Einstein condensed groundstate an exact, selfconsistent solution for the metric is presented. It is regular with a specific shape at the origin. The redshift at the horizon is finite but large, $z\\sim 10^{14}$$M_\\star/M$. The binding energy remains as an additional parameter to characterize the BH; alternatively, the mass observed at infinity can be any fraction of the rest mass of its constituents.

  19. Shape of black holes

    E-Print Network [OSTI]

    Clement, María E Gabach

    2015-01-01T23:59:59.000Z

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

  20. Exploring the string axiverse with precision black hole physics

    SciTech Connect (OSTI)

    Arvanitaki, Asimina [Berkeley Center for Theoretical Physics, University of California, Berkeley, California, 94720 (United States); Theoretical Physics Group, Lawrence Berkeley National Laboratory, Berkeley, California, 94720 (United States); Dubovsky, Sergei [Department of Physics, Stanford University, Stanford, California, 94305 (United States); Institute for Nuclear Research of the Russian Academy of Sciences, 60th October Anniversary Prospect, 7a, 117312 Moscow (Russian Federation)

    2011-02-15T23:59:59.000Z

    It has recently been suggested that the presence of a plenitude of light axions, an Axiverse, is evidence for the extra dimensions of string theory. We discuss the observational consequences of these axions on astrophysical black holes through the Penrose superradiance process. When an axion Compton wavelength is comparable to the size of a black hole, the axion binds to the black hole ''nucleus'' forming a gravitational atom in the sky. The occupation number of superradiant atomic levels, fed by the energy and angular momentum of the black hole, grows exponentially. The black hole spins down and an axion Bose-Einstein condensate cloud forms around it. When the attractive axion self-interactions become stronger than the gravitational binding energy, the axion cloud collapses, a phenomenon known in condensed matter physics as 'bosenova'. The existence of axions is first diagnosed by gaps in the mass vs spin plot of astrophysical black holes. For young black holes the allowed values of spin are quantized, giving rise to ''Regge trajectories'' inside the gap region. The axion cloud can also be observed directly either through precision mapping of the near-horizon geometry or through gravitational waves coming from the bosenova explosion, as well as axion transitions and annihilations in the gravitational atom. Our estimates suggest that these signals are detectable in upcoming experiments, such as Advanced LIGO, AGIS, and LISA. Current black hole spin measurements imply an upper bound on the QCD axion decay constant of 2x10{sup 17} GeV, while Advanced LIGO can detect signals from a QCD axion cloud with a decay constant as low as the GUT scale. We finally discuss the possibility of observing the {gamma}-rays associated with the bosenova explosion and, perhaps, the radio waves from axion-to-photon conversion for the QCD axion.

  1. Accretions of Dark Matter and Dark Energy onto ($n+2$)-dimensional Schwarzschild Black Hole and Morris-Thorne Wormhole

    E-Print Network [OSTI]

    Ujjal Debnath

    2015-03-06T23:59:59.000Z

    We have studied accretion of the dark matter and dark energy onto of $(n+2)$-dimensional Schwarzschild black hole and Morris-Thorne wormhole. The mass and the rate of change of mass for $(n+2)$-dimensional Schwarzschild black hole and Morris-Thorne wormhole have been found. We have assumed some candidates of dark energy like holographic dark energy, new agegraphic dark energy, quintessence, tachyon, DBI-essence, etc. The black hole mass and the wormhole mass have been calculated in term of redshift when dark matter and above types of dark energies accrete onto them separately. We have shown that the black hole mass increases and wormhole mass decreases for holographic dark energy, new agegraphic dark energy, quintessence, tachyon accretion and the slope of increasing/decreasing of mass sensitively depends on the dimension. But for DBI-essence accretion, the black hole mass first increases and then decreases and the wormhole mass first decreases and then increases and the slope of increasing/decreasing of mass not sensitively depends on the dimension.

  2. Accretions of Dark Matter and Dark Energy onto ($n+2$)-dimensional Schwarzschild Black Hole and Morris-Thorne Wormhole

    E-Print Network [OSTI]

    Debnath, Ujjal

    2015-01-01T23:59:59.000Z

    We have studied accretion of the dark matter and dark energy onto of $(n+2)$-dimensional Schwarzschild black hole and Morris-Thorne wormhole. The mass and the rate of change of mass for $(n+2)$-dimensional Schwarzschild black hole and Morris-Thorne wormhole have been found. We have assumed some candidates of dark energy like holographic dark energy, new agegraphic dark energy, quintessence, tachyon, DBI-essence, etc. The black hole mass and the wormhole mass have been calculated in term of redshift when dark matter and above types of dark energies accrete onto them separately. We have shown that the black hole mass increases and wormhole mass decreases for holographic dark energy, new agegraphic dark energy, quintessence, tachyon accretion and the slope of increasing/decreasing of mass sensitively depends on the dimension. But for DBI-essence accretion, the black hole mass first increases and then decreases and the wormhole mass first decreases and then increases and the slope of increasing/decreasing of mass...

  3. Accretions of Dark Matter and Dark Energy onto ($n+2$)-dimensional Schwarzschild Black Hole and Morris-Thorne Wormhole

    E-Print Network [OSTI]

    Ujjal Debnath

    2015-02-08T23:59:59.000Z

    We have studied accretion of the dark matter and dark energy onto of $(n+2)$-dimensional Schwarzschild black hole and Morris-Thorne wormhole. The mass and the rate of change of mass for $(n+2)$-dimensional Schwarzschild black hole and Morris-Thorne wormhole have been found. We have assumed some candidates of dark energy like holographic dark energy, new agegraphic dark energy, quintessence, tachyon, DBI-essence, etc. The black hole mass and the wormhole mass have been calculated in term of redshift when dark matter and above types of dark energies accrete onto them separately. We have shown that the black hole mass increases and wormhole mass decreases for holographic dark energy, new agegraphic dark energy, quintessence, tachyon accretion and the slope of increasing/decreasing of mass sensitively depends on the dimension. But for DBI-essence accretion, the black hole mass first increases and then decreases and the wormhole mass first decreases and then increases and the slope of increasing/decreasing of mass not sensitively depends on the dimension.

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

    E-Print Network [OSTI]

    Beth A. Brown; James Lindesay

    2008-11-04T23:59:59.000Z

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

  5. Relativistic Viscous Fluid Description of Microscopic Black Hole Wind

    E-Print Network [OSTI]

    J. I. Kapusta

    2001-05-25T23:59:59.000Z

    Microscopic black holes explode with their temperature varying inversely as their mass. Such explosions would lead to the highest temperatures in the present universe, all the way to the Planck energy. Whether or not a quasi-stationary shell of matter undergoing radial hydrodynamic expansion surrounds such black holes is been controversial. In this paper relativistic viscous fluid equations are applied to the problem. It is shown that a self-consistent picture emerges of a fluid just marginally kept in local thermal equilibrium; viscosity is a crucial element of the dynamics.

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

    E-Print Network [OSTI]

    S. S. Xulu

    2000-01-29T23:59:59.000Z

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

  7. On Brane Inflation Potentials and Black Hole Attractors

    E-Print Network [OSTI]

    Adil Belhaj; Pablo Diaz; Mohamed Naciri; Antonio Segui

    2007-11-16T23:59:59.000Z

    We propose a new potential in brane inflation theory, which is given by the arctangent of the square of the scalar field. Then we perform an explicit computation for inflationary quantities. This potential has many nice features. In the small field approximation, it reproduces the chaotic and MSSM potentials. It allows one, in the large field approximation, to implement the attractor mechanism for bulk black holes where the geometry on the brane is de Sitter. In particular, we show, up to some assumptions, that the Friedman equation can be reinterpreted as a Schwarzschild black hole attractor equation for its mass parameter.

  8. Do Supermassive Black Holes Exist at the Center of Galaxies?

    E-Print Network [OSTI]

    J. W. Moffat

    1998-03-22T23:59:59.000Z

    Models of superdense star clusters at the center of galaxies are investigated to see whether such objects can be stable and long-lived based on evaporation and collision time-scales and stability criteria. We find that physically reasonable models of massive clusters of stellar remnants can exist with masses $\\geq 10^6 M_{\\odot}$, which could simulate black holes at the center of galaxies with large $M/L$ ratios and gas motions of order $\\geq 10^3$ km $s^{-1}$. It follows that the evidence is not conclusive for massive dark objects at the center of galaxies being black holes.

  9. Isolated Horizons: A Generalization of Black Hole Mechanics

    E-Print Network [OSTI]

    Abhay Ashtekar; Christopher Beetle; Stephen Fairhurst

    1998-12-18T23:59:59.000Z

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

  10. Black Pine Circle Project

    ScienceCinema (OSTI)

    Mytko, Christine

    2014-09-15T23:59:59.000Z

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

  11. Black Pine Circle Project

    SciTech Connect (OSTI)

    Mytko, Christine

    2014-03-31T23:59:59.000Z

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

  12. Absolute conservation law for black holes

    E-Print Network [OSTI]

    D. Grumiller; W. Kummer

    1999-11-08T23:59:59.000Z

    In all 2d theories of gravity a conservation law connects the (space-time dependent) mass aspect function at all times and all radii with an integral of the matter fields. It depends on an arbitrary constant which may be interpreted as determining the initial value together with the initial values for the matter field. We discuss this for spherically reduced Einstein-gravity in a diagonal metric and in a Bondi-Sachs metric using the first order formulation of spherically reduced gravity, which allows easy and direct fixations of any type of gauge. The relation of our conserved quantity to the ADM and Bondi mass is investigated. Further possible applications (ideal fluid, black holes in higher dimensions or AdS spacetimes etc.) are straightforward generalizations.

  13. Black holes in massive gravity

    E-Print Network [OSTI]

    Babichev, Eugeny

    2015-01-01T23:59:59.000Z

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

  14. Impacts of generalized uncertainty principle on black hole thermodynamics and Salecker-Wigner inequalities

    SciTech Connect (OSTI)

    Tawfik, A., E-mail: a.tawfik@eng.mti.edu.eg [Egyptian Center for Theoretical Physics (ECTP), MTI University, 11571 Cairo (Egypt)

    2013-07-01T23:59:59.000Z

    We investigate the impacts of Generalized Uncertainty Principle (GUP) proposed by some approaches to quantum gravity such as String Theory and Doubly Special Relativity on black hole thermodynamics and Salecker-Wigner inequalities. Utilizing Heisenberg uncertainty principle, the Hawking temperature, Bekenstein entropy, specific heat, emission rate and decay time are calculated. As the evaporation entirely eats up the black hole mass, the specific heat vanishes and the temperature approaches infinity with an infinite radiation rate. It is found that the GUP approach prevents the black hole from the entire evaporation. It implies the existence of remnants at which the specific heat vanishes. The same role is played by the Heisenberg uncertainty principle in constructing the hydrogen atom. We discuss how the linear GUP approach solves the entire-evaporation-problem. Furthermore, the black hole lifetime can be estimated using another approach; the Salecker-Wigner inequalities. Assuming that the quantum position uncertainty is limited to the minimum wavelength of measuring signal, Wigner second inequality can be obtained. If the spread of quantum clock is limited to some minimum value, then the modified black hole lifetime can be deduced. Based on linear GUP approach, the resulting lifetime difference depends on black hole relative mass and the difference between black hole mass with and without GUP is not negligible.

  15. Preparation of supported electrocatalyst comprising multiwalled carbon nanotubes

    DOE Patents [OSTI]

    Wu, Gang; Zelenay, Piotr

    2013-08-27T23:59:59.000Z

    A process for preparing a durable non-precious metal oxygen reduction electrocatalyst involves heat treatment of a ball-milled mixture of polyaniline and multiwalled carbon nanotubes in the presence of a Fe species. The catalyst is more durable than catalysts that use carbon black supports. Performance degradation was minimal or absent after 500 hours of operation at constant cell voltage of 0.40 V.

  16. Low Carbon Fuel Standards

    E-Print Network [OSTI]

    Sperling, Dan; Yeh, Sonia

    2009-01-01T23:59:59.000Z

    gas, or even coal with carbon capture and sequestration. Afuels that facilitate carbon capture and sequestration. Forenergy and could capture and sequester carbon emissions.

  17. Capturing carbon | EMSL

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

    carbon Released: October 02, 2011 New technology enables molecular-level insight into carbon sequestration Carbon sequestration is a potential solution for reducing greenhouse...

  18. Tectonic setting and origin of the Black Warrior basin

    SciTech Connect (OSTI)

    Thomas, W.A.; Whiting, B.M. (Univ. of Kentucky, Lexington, KY (United States). Dept. of Geological Sciences)

    1994-03-01T23:59:59.000Z

    The Black Warrior basin has a triangular outline that is framed by the Ouachita thrust belt on the southwest, the Appalachian thrust belt on the southeast, and the North American craton on the north. The stratigraphy of the Black Warrior basin includes two distinct parts: a Cambrian-Mississippian passive-margin carbonate-shelf succession, and a Mississippian-Pennsylvanian clastic succession, the lower (Mississippian) part of which grades northeastward into a carbonate-shelf facies. The provenance and dispersal system of the Mississippian-Pennsylvanian clastic deposits have been interpreted in four different ways, each of which has significantly different implications for origin of the basin: (1) Ouachita orogenic source and northeastward prograding; (2) Alabama Appalachian orogenic source and northwestward prograding; (3) Georgia-tennessee Appalachian orogenic source and westward prograding; and (4) cratonic source and southward prograding. Subsidence history determined from calculations of decompacted thickness indicates that (1) the Black Warrior basin is an orogenic foreland basin related primarily to the Ouachita thrust load on the southwest; (2) later emplacement of the Alabama Appalachian thrust belt modified the southeastern side of the Ouachita-related Black Warrior foreland basin; and (3) a separate foreland basin, representing the southern end of the Appalachian foreland basin, formed in response to the Georgia-Tennessee Appalachian thrust load. The previously used criteria do not necessarily support a unique interpretation, but synthesizing these data with subsidence history leads to the conclusion that the Black Warrior basin is a tectonically driven, orogenic foreland basin dominated by Ouachita thrusting and modified by Appalachian thrusting.

  19. Oscillating axion bubbles as alternative to supermassive black holes at galactic centers

    E-Print Network [OSTI]

    Anatoly A. Svidzinsky

    2007-10-30T23:59:59.000Z

    Recent observations of near-infrared and X-ray flares from Sagittarius A*, which is believed to be a supermassive black hole at the Galactic center, show that the source exhibits about 20-minute periodic variability. Here we provide arguments based on a quantitative analysis that supermassive objects at galactic centers may be bubbles of dark matter axions rather than black holes. An oscillating axion bubble can explain periodic variability of Sagittarius A* and yields the axion mass about 0.6 meV which fits in the open axion mass window. The bubble scenario with no other free parameters explains lack of supermassive "black holes" with mass Maxion bubble can not exceed 1.5\\times 10^9 M_{Sun}, in agreement with the upper limit on the supermassive "black hole" mass obtained from observations. Our finding, if confirmed, suggests that Einstein general relativity is invalid for strong gravity and the gravitational field for the bubble effectively becomes repulsive at large potential. Imaging a shadow of the "black hole" at the Galactic center with VLBI in the next decade can distinguish between the black hole and the oscillating axion bubble scenarios. In the case of axion bubble, a steady shadow will not be observed. Instead, the shadow will appear and disappear periodically with a period of about 20 min.

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

    E-Print Network [OSTI]

    Rong-Gen Cai; Hai-Qing Zhang

    2009-12-03T23:59:59.000Z

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

  1. Holographic superconductors with Horava-Lifshitz black holes

    SciTech Connect (OSTI)

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

    2010-03-15T23:59:59.000Z

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

  2. Dermoscopy of black-spot poison ivy

    E-Print Network [OSTI]

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

    2012-01-01T23:59:59.000Z

    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

  3. Why Blue-Collar Blacks Help Less

    E-Print Network [OSTI]

    Smith, Sandra Susan; Young, Kara Alexis

    2013-01-01T23:59:59.000Z

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

  4. Carbon supercapacitors

    SciTech Connect (OSTI)

    Delnick, F.M.

    1993-11-01T23:59:59.000Z

    Carbon supercapacitors are represented as distributed RC networks with transmission line equivalent circuits. At low charge/discharge rates and low frequencies these networks approximate a simple series R{sub ESR}C circuit. The energy efficiency of the supercapacitor is limited by the voltage drop across the ESR. The pore structure of the carbon electrode defines the electrochemically active surface area which in turn establishes the volume specific capacitance of the carbon material. To date, the highest volume specific capacitance reported for a supercapacitor electrode is 220F/cm{sup 3} in aqueous H{sub 2}SO{sub 4} (10) and {approximately}60 F/cm{sup 3} in nonaqueous electrolyte (8).

  5. Quantification of soil organic carbon using mid- and near- DRIFT spectroscopy

    E-Print Network [OSTI]

    Kang, Misun

    2004-09-30T23:59:59.000Z

    (X) and soil property data (Y) into a new smaller set of latent variables and their scores that best describe all the variance in the data. Oxidizable organic carbon content was measured by a modified Walkley-Black method, and total organic carbon...

  6. Sequencing the Black Aspergilli species complex

    SciTech Connect (OSTI)

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

    2011-03-11T23:59:59.000Z

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

  7. Carbon microtubes

    DOE Patents [OSTI]

    Peng, Huisheng (Shanghai, CN); Zhu, Yuntian Theodore (Cary, NC); Peterson, Dean E. (Los Alamos, NM); Jia, Quanxi (Los Alamos, NM)

    2011-06-14T23:59:59.000Z

    A carbon microtube comprising a hollow, substantially tubular structure having a porous wall, wherein the microtube has a diameter of from about 10 .mu.m to about 150 .mu.m, and a density of less than 20 mg/cm.sup.3. Also described is a carbon microtube, having a diameter of at least 10 .mu.m and comprising a hollow, substantially tubular structure having a porous wall, wherein the porous wall comprises a plurality of voids, said voids substantially parallel to the length of the microtube, and defined by an inner surface, an outer surface, and a shared surface separating two adjacent voids.

  8. Black Stars and Gamma Ray Bursts

    E-Print Network [OSTI]

    Tanmay Vachaspati

    2007-06-08T23:59:59.000Z

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

  9. Idaho_BlackCanyon

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh School footballHydrogenIT | NationalMentoringWind Power -Mtn. Black

  10. Carbon nanowalls grown by microwave plasma enhanced chemical vapor deposition during the carbonization of polyacrylonitrile fibers

    SciTech Connect (OSTI)

    Li Jiangling; Su Shi; Kundrat, Vojtech; Abbot, Andrew M.; Ye, Haitao [School of Engineering and Applied Science, Aston University, Birmingham B4 7ET (United Kingdom); Zhou Lei [Department of Metallurgy and Materials, University of Birmingham, Birmingham B15 2TT (United Kingdom); Mushtaq, Fajer [Department of Mechanical Engineering, ETH Zurich, Zurich 8092 (Switzerland); Ouyang Defang [School of Life and Health Science, Aston University, Birmingham B4 7ET (United Kingdom); James, David; Roberts, Darren [Thermo Fisher Scientific, Stafford House, Hemel Hempstead HP2 7GE (United Kingdom)

    2013-01-14T23:59:59.000Z

    We used microwave plasma enhanced chemical vapor deposition (MPECVD) to carbonize an electrospun polyacrylonitrile (PAN) precursor to form carbon fibers. Scanning electron microscopy, Raman spectroscopy, and Fourier transform infrared spectroscopy were used to characterize the fibers at different evolution stages. It was found that MPECVD-carbonized PAN fibers do not exhibit any significant change in the fiber diameter, whilst conventionally carbonized PAN fibers show a 33% reduction in the fiber diameter. An additional coating of carbon nanowalls (CNWs) was formed on the surface of the carbonized PAN fibers during the MPECVD process without the assistance of any metallic catalysts. The result presented here may have a potential to develop a novel, economical, and straightforward approach towards the mass production of carbon fibrous materials containing CNWs.

  11. Revisit Carbon/Sulfur Composite for Li-S Batteries

    SciTech Connect (OSTI)

    Zheng, Jianming; Gu, Meng; Wagner, Michael J.; Hays, Kevin; Li, Xiaohong S.; Zuo, Pengjian; Wang, Chong M.; Zhang, Jiguang; Liu, Jun; Xiao, Jie

    2013-07-23T23:59:59.000Z

    To correlate the carbon properties e.g. surface area and porous structure, with the electrochemical behaviors of carbon/sulfur (C/S) composite cathodes for lithium-sulfur (Li-S) batteries, four different carbon frameworks including Ketjen Black (KB, high surface area and porous), Graphene (high surface area and nonporous), Acetylene Black (AB, low surface area and nonporous) and Hollow Carbon Nano Sphere (HCNS, low surface area and porous) are employed to immobilize sulfur (80 wt.%). It has been revealed that high surface area of carbon improves the utilization rate of active sulfur and decreases the real current density during the electrochemical reactions. Accordingly, increased reversible capacities and reduced polarization are observed for high surface area carbon hosts such as KB/S and graphene/S composites. The porous structure of KB or HCNS matrix promotes the long-term cycling stability of C/S composites but only at relatively low rate (0.2 C). Once the current density increases, the pore effect completely disappears and all Li-S batteries show similar trend of capacity degradation regardless of the different carbon hosts used in the cathodes. The reason has been assigned to the formation of reduced amount of irreversible Li2S on the cathode as well as shortened time for polysulfides to transport towards lithium anode at elevated current densities. This work provides valuable information for predictive selection on carbon materials to construct C/S composite for practical applications from the electrochemical point of view.

  12. Carbon Storage Program

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

    Carbon Sequestration Partnership MSU . . . . . . . . . . . . . . . . . . . . . . . Montana State University MVA . . . . . . . . . . . . . . . . . . . . . . . Monitoring,...

  13. Black holes, cuspy atmospheres, and galaxy formation

    E-Print Network [OSTI]

    James Binney

    2004-07-12T23:59:59.000Z

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

  14. Effect of sulfidity on the corrosivity of white, green, and black liquors

    SciTech Connect (OSTI)

    Wensley, A.; Champagne, P.

    1999-07-01T23:59:59.000Z

    Corrosion testing was performed in white, green, and black liquors from a kraft mill. The liquors were modified in composition to simulate conditions of high (40%) sulfidity and low (30%) sulfidity, and then heated in laboratory autoclaves to the temperatures of the respective tanks from which the samples were taken. Specimens of carbon and stainless steels were exposed under free corrosion potential conditions, and their corrosion rates determined from weight loss measurements. In white, green, 45% solids black, and flash tank liquors, active corrosion rates for the carbon steels were typically 20 to 75% higher in the higher sulfidity liquors. In 15% solids weak black liquor there was no appreciable difference in corrosion rates, with carbon steels remaining passive in both low and high sulfidity. In 26% solids intermediate black liquor there were large increases in the corrosion rates of carbon steel between low and high sulfidity liquors, resulting from a change from passive to active conditions. Stainless steels UNS S30403, S32304, and S31803 had very low corrosion rates in all the liquors tested, regardless of sulfidity.

  15. Optical black holes and solitons

    E-Print Network [OSTI]

    Shawn Westmoreland

    2010-12-21T23:59:59.000Z

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

  16. Black Beans and Rice Ingredients

    E-Print Network [OSTI]

    Liskiewicz, Maciej

    Black Beans and Rice Ingredients: 1 teaspoon vegetable oil 1 medium onion, chopped 2 bay leaves 4 cloves garlic, minced 2 (15 oz.) cans black beans, drained and rinsed 1 tbsp. cilantro 15 ounces low-fat, shredded Directions 1. Rinse beans with water in colander to remove sodium. 2. Sauté onions, garlic

  17. Black Bean Stuffed Peppers Ingredients

    E-Print Network [OSTI]

    Liskiewicz, Maciej

    except cheese. 4. Fill each pepper half with bean mixture and place in pan. 5. Pour 1/4 cup waterBlack Bean Stuffed Peppers Ingredients: Non stick cooking spray 3 green peppers 15 ounces black beans, canned, drained and rinsed to remove sodium 8 ounces corn, canned 1 cup brown rice, cooked 1

  18. Process for the conversion of carbonaceous feedstocks to particulate carbon and methanol

    DOE Patents [OSTI]

    Steinberg, Meyer (Melville, NY); Grohse, Edward W. (Port Jefferson, NY)

    1995-01-01T23:59:59.000Z

    A process for the production of a pollutant-free particulate carbon (i.e., a substantially ash-, sulfur- and nitrogen-free carbon) from carbonaceous feedstocks. The basic process involves de-oxygenating one of the gas streams formed in a cyclic hydropyrolysis-methane pyrolysis process in order to improve conversion of the initial carbonaceous feedstock. De-oxygenation is effected by catalytically converting carbon monoxide, carbon dioxide, and hydrogen contained in one of the pyrolysis gas streams, preferably the latter, to a methanol co-product. There are thus produced two products whose use is known per se, viz., a substantially pollutant-free particulate carbon black and methanol. These products may be admixed in the form of a liquid slurry of carbon black in methanol.

  19. Process for the conversion of carbonaceous feedstocks to particulate carbon and methanol

    DOE Patents [OSTI]

    Steinberg, M.; Grohse, E.W.

    1995-06-27T23:59:59.000Z

    A process is described for the production of a pollutant-free particulate carbon (i.e., a substantially ash-, sulfur- and nitrogen-free carbon) from carbonaceous feedstocks. The basic process involves de-oxygenating one of the gas streams formed in a cyclic hydropyrolysis-methane pyrolysis process in order to improve conversion of the initial carbonaceous feedstock. De-oxygenation is effected by catalytically converting carbon monoxide, carbon dioxide, and hydrogen contained in one of the pyrolysis gas streams, preferably the latter, to a methanol co-product. There are thus produced two products whose use is known per se, viz., a substantially pollutant-free particulate carbon black and methanol. These products may be admixed in the form of a liquid slurry of carbon black in methanol. 3 figs.

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

    E-Print Network [OSTI]

    A. J. S. Hamilton

    2013-05-20T23:59:59.000Z

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

  1. New approaches for the chemical and physical characterization of aerosols using a single particle mass spectrometry based technique

    E-Print Network [OSTI]

    Spencer, Matthew Todd

    2007-01-01T23:59:59.000Z

    1-2% of the oil mass, however the calcium ion peak at m/z 40and elemental carbon (EC) peaks. The HDDV oil mass spectraoil mass spectra were characterized by an intense Ca + ion peak and

  2. Low Carbon Fuel Standards

    E-Print Network [OSTI]

    Sperling, Dan; Yeh, Sonia

    2009-01-01T23:59:59.000Z

    gas, or even coal with carbon capture and sequestration. Afuels that facilitate carbon capture and sequestration. For

  3. Methanation of Carbon Dioxide

    E-Print Network [OSTI]

    Goodman, Daniel Jacob

    2013-01-01T23:59:59.000Z

    cycle plants, possibly with carbon capture and storage (CCS)natural gas plant with carbon capture and storage technology

  4. Methanation of Carbon Dioxide

    E-Print Network [OSTI]

    Goodman, Daniel Jacob

    2013-01-01T23:59:59.000Z

    gas plant with carbon capture and storage technology werewith carbon capture and storage (CCS) technology, to replace

  5. Black holes with gravitational hair in higher dimensions

    SciTech Connect (OSTI)

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

    2011-10-15T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Dean Rasheed

    1995-05-06T23:59:59.000Z

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

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

    E-Print Network [OSTI]

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

    2015-02-27T23:59:59.000Z

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

  8. Acceleration of particles by black holes: kinematic explanation

    E-Print Network [OSTI]

    O. B. Zaslavskii

    2011-06-21T23:59:59.000Z

    A new simple and general explanation of the effect of acceleration of particles by black holes to infinite energies in the centre of mass frame is suggested. It is based on kinematics of particles moving near the horizon. This effect arises when particles of two kinds collide near the horizon. For massive particles, the first kind represents a particle with the generic energy and angular momentum (I call them "usual"). Near the horizon, such a particle has a velocity almost equal to that of light in the frame that corotates with a black hole (the frame is static if a black hole is static). The second kind (called "critical") consists of particles with the velocity vvelocity approaches the speed of light c, the Lorentz factor grows unbound. This explanation applies both to generic rotating black holes and charged ones (even for radial motion of particles). If one of colliding particles is massless (photon), the critical particle is distinguished by the fact that its frequency is finite near the horizon. The existence (or absence) of the effect is determined depending on competition of two factors - gravitational blue shift for a photon propagating towards a black hole and the Doppler effect due to transformation from the locally nonrotating frame to a comoving one. Classification of all possible types of collisions is suggested depending on whether massive or massless particle is critical or usual.

  9. Thermodynamics and Gauge Gravity Correspondence for a Generalized Charged Rotating Black Hole

    E-Print Network [OSTI]

    Majeed, Bushra

    2015-01-01T23:59:59.000Z

    We investigate the thermodynamics of Kerr-Newman-Kasuya black hole on the inner and outer horizons. Products of surface gravities, surface temperatures, Komar energies, electromagnetic potentials, angular velocities, areas, entropies, horizon radii and the irreducible masses at the Cauchy and the Event horizons are calculated. It is observed that the product of surface gravities, surface temperature product and product of Komar energies, electromagnetic potentials and angular velocities at the horizons are not universal quantities for Kerr-Newman-Kasuya black hole. Products of areas and entropies at both the horizons are independent of mass of the black hole. Heat capacity is calculated and phase transition is observed, under certain conditions on r. Using the thermodynamics method with quantized charges (known as re?ned thermodynamics), the central charges and the holographic pictures (J-picture, Q-picture, and P-picture) of the dual CFT for Kerr-Newman-Kasuya black hole are determined.

  10. Thermodynamics and Gauge Gravity Correspondence for a Generalized Charged Rotating Black Hole

    E-Print Network [OSTI]

    Bushra Majeed; Mubasher Jamil

    2015-07-06T23:59:59.000Z

    We investigate the thermodynamics of Kerr-Newman-Kasuya black hole on the inner and outer horizons. Products of surface gravities, surface temperatures, Komar energies, electromagnetic potentials, angular velocities, areas, entropies, horizon radii and the irreducible masses at the Cauchy and the Event horizons are calculated. It is observed that the product of surface gravities, surface temperature product and product of Komar energies, electromagnetic potentials and angular velocities at the horizons are not universal quantities for Kerr-Newman-Kasuya black hole. Products of areas and entropies at both the horizons are independent of mass of the black hole. Heat capacity is calculated and phase transition is observed, under certain conditions on r. Using the thermodynamics method with quantized charges (known as re?ned thermodynamics), the central charges and the holographic pictures (J-picture, Q-picture, and P-picture) of the dual CFT for Kerr-Newman-Kasuya black hole are determined.

  11. Primordial black holes from temporally enhanced curvature perturbation

    E-Print Network [OSTI]

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

    2014-06-02T23:59:59.000Z

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

  12. Carbon Additionality: Discussion Paper

    E-Print Network [OSTI]

    Carbon Additionality: A review Discussion Paper Gregory Valatin November 2009 Forest Research. Voluntary Carbon Standards American Carbon Registry Forest Carbon Project Standard (ACRFCPS) 27 CarbonFix Standard (CFS) 28 Climate, Community and Biodiversity Standard (CCBS) 28 Forest Carbon Standard (FCS) 28

  13. Long-term Black Carbon Dynamics in Cultivated Soil. | EMSL

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

    at 8 conversion ages stretching over 100 years and from a forest soil sample from Kenya, were manually picked under a light microscope for characterization and...

  14. aerosol black carbon: Topics by E-print Network

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

    of solar radiation by atmospheric aerosols is a key el- ement of the Earth's radiative energy balance and climate. The optical properties of aerosol particles are, however,...

  15. BLACK CARBON: Climate Impact of Bushfire in Australia 

    E-Print Network [OSTI]

    Porter, Stephen D.

    2013-01-01T23:59:59.000Z

    Fire is a ubiquitous feature of the Australian landscape – characteristics of natural flora suggest that fire has been commonplace since well before the arrival of man some 40,000 years ago. Emissions from bushfire at a ...

  16. Black carbon refractive index and morphology: a Laboratory study

    E-Print Network [OSTI]

    Oxford, University of

    radiative properties derived from Mie theory and therefore limited to the assumption of spherical aerosol cake 2.6 Heavy fuel oil 1.5 Figure 2: Global sources by fuel types [7]. A wide range of fuel types

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

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del(ANL-IN-03-032)8LigovCampaignsCLEX-5 Campaign Comments? We

  18. Gravitational Waves from Coalescing Binary Black Holes: Theoretical and Experimental Challenges

    ScienceCinema (OSTI)

    None

    2011-10-06T23:59:59.000Z

    A network of ground-based interferometric gravitational wave detectors (LIGO/VIRGO/GEO/...) is currently taking data near its planned sensitivity. Coalescing black hole binaries are among the most promising, and most exciting, gravitational wave sources for these detectors. The talk will review the theoretical and experimental challenges that must be met in order to successfully detect gravitational waves from coalescing black hole binaries, and to be able to reliably measure the physical parameters of the source (masses, spins, ...).

  19. Binary Black Holes in Quasi-Stationary Circular Orbits

    E-Print Network [OSTI]

    Brian D. Baker

    2002-05-18T23:59:59.000Z

    We propose a method of determining solutions to the constraint equations of General Relativity approximately describing binary black holes in quasi-stationary circular orbits. Black holes with arbitrary linear momenta are constructed in the manner suggested by Brandt and Brugmann. The quasi-stationary circular orbits are determined by local minima in the ADM mass in a manner similar to Baumgarte and Cook; however, rather than fixing the area of the apparent horizon, we fix the value of the bare masses of the holes. We numerically generate an evolutionary sequence of quasi-stationary circular orbits up to and including the innermost stable circular orbit. We compare our results with post-Newtonian expectations as well as the results of Cook and Baumgarte. We also generate additional numerical results describing the dynamics of the geometry due to the emission of gravitational radiation.

  20. Supermassive black holes (SMBH) and formation of galaxies

    E-Print Network [OSTI]

    F. Combes

    2003-07-31T23:59:59.000Z

    The recently confirmed correlation between the mass of SMBH and bulges of galaxies (and their central velocity dispersion), suggest a common formation scenario for galaxies and their central black holes. Common fueling can be invoked through internal dynamical processes, external accretion, and hierarchical merging of structures. The success of recent theories is reviewed, as the self-regulated growth of both bulges and SMBHs, the predicted AGN statistics, when activity is triggered by accretion and mergers, the predicted frequency of binary SMBH and consequences. In particular, the SMBH growth problem can now be revised, invoking intermediate-mass black holes (IMBH) as BH seeds in the early universe. As a by-product, the merger of binary SMBHs help to heat and destroy central stellar cusps. Remaining problems are mentioned.

  1. Elastic scattering of Dirac fermions on Schwarzschild black holes

    E-Print Network [OSTI]

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

    2015-02-11T23:59:59.000Z

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

  2. Mergers of Supermassive Black Holes in Astrophysical Environments

    E-Print Network [OSTI]

    Tanja Bode; Tamara Bogdanovic; Roland Haas; James Healy; Pablo Laguna; Deirdre Shoemaker

    2011-10-12T23:59:59.000Z

    Modeling the late inspiral and merger of supermassive black holes is central to understanding accretion processes and the conditions under which electromagnetic emission accompanies gravitational waves. We use fully general relativistic, hydrodynamics simulations to investigate how electromagnetic signatures correlate with black hole spins, mass ratios, and the gaseous environment in this final phase of binary evolution. In all scenarios, we find some form of characteristic electromagnetic variability whose pattern depends on the spins and binary mass ratios. Binaries in hot accretion flows exhibit a flare followed by a sudden drop in luminosity associated with the plunge and merger, as well as quasi-periodic oscillations correlated with the gravitational waves during the inspiral. Conversely, circumbinary disk systems are characterized by a low luminosity of variable emission, suggesting challenging prospects for their detection.

  3. Fundamental Study of Black Liquor Gasification Kinetics. Quarterly progress report for the period October 1999 to December 1999

    SciTech Connect (OSTI)

    NONE

    2000-01-31T23:59:59.000Z

    The overall objective of this research is to evaluate the kinetics of gasification of kraft black liquor under laboratory conditions simulating pressurized, oxygen-blown gasification. The significant independent variables are gasifier temperature, black liquor composition particle size, and particle residence time. The authors will quantify their impact on the concentration of major and trace gas phase species, as well as the composition of condensed phase inorganic products, including specification of the Na- and S-containing compounds and overall carbon conversion.

  4. Estimating body mass of pumas (Puma concolor) Brian D. JansenA,B

    E-Print Network [OSTI]

    the relationships between body measurements and body mass for 58 pumas in the Black Hills. We then applied our top equation to eight pumas that we captured in areas outside the Black Hills study population. Key results. We, Weckerly et al. 1987), East African ungulates (Talbot and McCulloch 1965), elk (Cervus elaphus, Millspaugh

  5. Using radio emission to detect isolated and quiescent accreting black holes

    E-Print Network [OSTI]

    Thomas J. Maccarone

    2005-03-05T23:59:59.000Z

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

  6. General Non-extremal Rotating Charged Godel Black Holes in Minimal Five-Dimensional Gauged Supergravity

    E-Print Network [OSTI]

    Shuang-Qing Wu

    2007-12-07T23:59:59.000Z

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

  7. The Maximum Mass of a Neutron Star

    E-Print Network [OSTI]

    Vassiliki Kalogera; Gordon Baym

    1996-08-11T23:59:59.000Z

    Observational identification of black holes as members of binary systems requires the knowledge of the upper limit on the gravitational mass of a neutron star. We use modern equations of state for neutron star matter, fitted to experimental nucleon-nucleon scattering data and the properties of light nuclei, to calculate, within the framework of Rhoades & Ruffini (1974), the minimum upper limit on a neutron star mass. Regarding the equation of state as valid up to twice nuclear matter saturation density, rho_{nm}, we obtain a secure upper bound on the neutron star mass equal to 2.9 solar masses. We also find that in order to reach the lowest possible upper bound of 2.2 solar masses, we need understand the physical properties of neutron matter up to a density of about 4 times rho_{nm}.

  8. The Efficiency of Gravitational Bremsstrahlung Production in the Collision of Two Schwarzschild Black Holes

    E-Print Network [OSTI]

    R. F. Aranha; H. P. de Oliveira; I. Damiăo Soares; E. V. Tonini

    2008-04-22T23:59:59.000Z

    We examine the efficiency of gravitational bremsstrahlung production in the process of head-on collision of two boosted Schwarzschild black holes. We constructed initial data for the characteristic initial value problem in Robinson-Trautman spacetimes, that represent two instantaneously stationary Schwarzschild black holes in motion towards each other with the same velocity. The Robinson-Trautman equation was integrated for these initial data using a numerical code based on the Galerkin method. The final resulting configuration is a boosted black hole with Bondi mass greater than the sum of the individual mass of each initial black hole. Two relevant aspects of the process are presented. The first relates the efficiency $\\Delta$ of the energy extraction by gravitational wave emission to the mass of the final black hole. This relation is fitted by a distribution function of non-extensive thermostatistics with entropic parameter $q \\simeq 1/2$; the result extends and validates analysis based on the linearized theory of gravitational wave emission. The second is a typical bremsstrahlung angular pattern in the early period of emission at the wave zone, a consequence of the deceleration of the black holes as they coalesce; this pattern evolves to a quadrupole form for later times.

  9. Spectrum of the radiation from electric charges and from dipoles which free infall into a black hole

    E-Print Network [OSTI]

    A. A. Shatskiy; I. D. Novikov; L. N. Lipatova

    2013-03-30T23:59:59.000Z

    The free fall of electric charges and dipoles, radial and freely falling into the Schwarzschild black hole event horizon, was considered. Inverse effect of electromagnetic fields on the black hole is neglected. Dipole was considered as a point particle, so the deformation associated with exposure by tidal forces are neglected. According to the theorem, "the lack of hair" of black holes, multipole magnetic fields must be fully emitted by multipole fall into a black hole. The spectrum of electromagnetic radiation power for these multipoles (monopole and dipole) was found. Differences were found in the spectra for different orientations of the falling dipole. A general method has been developed to find radiated electromagnetic multipole fields for the free falling multipoles into a black hole (including higher order multipoles - quadrupoles, etc.). The electromagnetic spectrum can be compared with observational data from stellar mass and smaller black holes.

  10. Optimization in the Parikh-Wilczek tunneling model of Hawking radiation for Kerr-Newman Black Holes

    E-Print Network [OSTI]

    Auttakit Chatrabhuti; Khem Upathambhakul

    2014-03-17T23:59:59.000Z

    In this short report, we investigate the mutual information hidden in the Parikh-Wilczek tunneling model of Hawking radiation for Kerr-Newman black holes. By assuming the radiation as an optimization process, we discuss its effect on time evolution of rotating (charged and uncharged) black holes. For uncharged rotating black holes evaporating under the maximum mutual information optimization, their scale invariant rotation parameter $a_*=a/M$ is almost constant at the early stage but rapidly increase at the very last stage of the evaluation process. The value of rotation parameter at the final state of evaporation depends on the initial condition of the black hole. We also found that the presence of electric charge can cause the black holes lose their angular momentum more rapidly than they lose mass. The charged-rotating black holes asymptotically approach a state which is described by $a_*= 0$ and $Q/M = 1$.

  11. NOAA Technical Memorandum ERL GLERL-75 Sediment Trap Study in the Green Bay Mass Balance Program

    E-Print Network [OSTI]

    : Mass and Organic Carbon Fluxes, Resuspension, and Particle Settling Velocities Brian J. Eadie Gerald L ................................................................................................. 23 4.5 Flux Profiles and Estimates of Sediment Resuspension

  12. Carbon Trading, Carbon Taxes and Social Discounting

    E-Print Network [OSTI]

    Weiblen, George D

    Carbon Trading, Carbon Taxes and Social Discounting Elisa Belfiori belf0018@umn.edu University of Minnesota Abstract This paper considers the optimal design of policies to carbon emissions in an economy, such as price or quantity controls on the net emissions of carbon, are insufficient to achieve the social

  13. Black optic display

    DOE Patents [OSTI]

    Veligdan, James T. (Manorville, NY)

    1997-01-01T23:59:59.000Z

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

  14. Strings, higher curvature corrections, and black holes

    E-Print Network [OSTI]

    Thomas Mohaupt

    2005-12-05T23:59:59.000Z

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

  15. Opposite charged two-body system of identical counter-rotating black holes

    E-Print Network [OSTI]

    I. Cabrera-Munguia; Claus Lämmerzahl; L. A. López; Alfredo Macías

    2014-05-12T23:59:59.000Z

    A 4-parametric exact solution describing a two-body system of identical Kerr-Newman counter-rotating black holes endowed with opposite electric/magnetic charges is presented. The axis conditions are solved in order to really describe two black holes separated by a massless strut. Moreover, the explicit form of the horizon half length parameter sigma in terms of physical Komar parameters, i.e., the Komar mass M, electric charge QE, angular momentum J, and a coordinate distance R is derived. Additionally, magnetic charges QB arise from the rotation of electrically charged black holes. As a consequence, in order to account for the contribution to the mass of the magnetic charge, the usual Smarr mass formula should be generalized, as it is proposed by A. Tomimatsu, Prog. Theor. Phys. 72, 73 (1984).

  16. Public Review Draft: A Method for Assessing Carbon Stocks, Carbon

    E-Print Network [OSTI]

    Public Review Draft: A Method for Assessing Carbon Stocks, Carbon Sequestration, and Greenhouse, and Zhu, Zhiliang, 2010, Public review draft; A method for assessing carbon stocks, carbon sequestration

  17. Carbon-Optimal and Carbon-Neutral Supply Chains

    E-Print Network [OSTI]

    Caro, F.; Corbett, C. J.; Tan, T.; Zuidwijk, R.

    2011-01-01T23:59:59.000Z

    Li, M. Daskin. 2009. Carbon Footprint and the Management ofThe Importance of Carbon Footprint Estimation Boundaries.Carbon accounting and carbon footprint - more than just

  18. Growth of Early Supermassive Black Holes and the High-Redshift Eddington Ratio Distribution

    E-Print Network [OSTI]

    DeGraf, Colin; Khandai, Nishikanta; Croft, Rupert

    2012-01-01T23:59:59.000Z

    Using a new large-scale (~ 0.75 Gpc)^3 hydrodynamic cosmological simulation we investigate the growth rate of supermassive black holes in the early universe (z > 4.75). Remarkably, we find a clear peak in the typical Eddington ratio at black hole masses of 4-8 * 10^7 solar masses (typically found in halos of ~7 * 10^11 to 10^12 solar masses), independent of redshift and indicative that most of BH growth occurs in the cold-flow dominated regime. Black hole growth is by and large regulated by the evolution of gas density. The typical Eddington ratio at a given mass scales simply as cosmological density (1+z)^3 and the peak is caused by the competition between increased gas density available in more massive hosts, and a decrease due to strong AGN feedback that deprives the black hole of sufficient gas to fuel further rapid growth in the high mass end. In addition to evolution in the mean Eddington ratio, we show that the distribution of Eddington ratio among both mass-selected and luminosity-selected samples is ...

  19. Simulations of black hole-neutron star binary coalescence

    E-Print Network [OSTI]

    William H. Lee

    2001-01-09T23:59:59.000Z

    We show the results of dynamical simulations of the coalescence of black hole-neutron star binaries. We use a Newtonian Smooth Particle Hydrodynamics code, and include the effects of gravitational radiation back reaction with the quadrupole approximation for point masses, and compute the gravitational radiation waveforms. We assume a polytropic equation of state determines the structure of the neutron star in equilibrium, and use an ideal gas law to follow the dynamical evolution. Three main parameters are explored: (i) The distribution of angular momentum in the system in the initial configuration, namely tidally locked systems vs. irrotational binaries; (ii) The stiffness of the equation of state through the value of the adiabatic index Gamma (ranging from Gamma=5/3 to Gamma=3); (iii) The initial mass ratio q=M(NS)/M(BH). We find that it is the value of Gamma that determines how the coalescence takes place, with immediate and complete tidal disruption for Gamma less than 2, while the core of the neutron star survives and stays in orbit around the black hole for Gamma=3. This result is largely independent of the initial mass ratio and spin configuration, and is reflected directly in the gravitational radiation signal. For a wide range of mass ratios, massive accretion disks are formed (M(disk)~0.2 solar masses), with baryon-free regions that could possibly give rise to gamma ray bursts.

  20. EM counterparts of recoiling black holes: general relativistic simulations of non-Keplerian discs

    E-Print Network [OSTI]

    Olindo Zanotti; Luciano Rezzolla; Luca Del Zanna; Carlos Palenzuela

    2010-09-12T23:59:59.000Z

    We investigate the dynamics of a circumbinary disc that responds to the loss of mass and to the recoil velocity of the black hole produced by the merger of a binary system of supermassive black holes. We perform the first two-dimensional general relativistic hydrodynamics simulations of \\textit{extended} non-Keplerian discs and employ a new technique to construct a "shock detector", thus determining the precise location of the shocks produced in the accreting disc by the recoiling black hole. In this way we can study how the properties of the system, such as the spin, mass and recoil velocity of the black hole, affect the mass accretion rate and are imprinted on the electromagnetic emission from these sources. We argue that the estimates of the bremsstrahlung luminosity computed without properly taking into account the radiation transfer yield cooling times that are unrealistically short. At the same time we show, through an approximation based on the relativistic isothermal evolution, that the luminosity produced can reach a peak value above $L \\simeq 10^{43} \\ {\\rm erg/s} $ at about $\\sim 30\\,{\\rm d}$ after the merger of a binary with total mass $M\\simeq 10^6 M_\\odot$ and persist for several days at values which are a factor of a few smaller. If confirmed by more sophisticated calculations such a signal could indeed lead to an electromagnetic counterpart of the merger of binary black-hole system.

  1. Spin alignment and differential accretion in merging black-hole binaries

    E-Print Network [OSTI]

    Gerosa, Davide; Lodato, Giuseppe; Rosotti, Giovanni

    2015-01-01T23:59:59.000Z

    Interactions between a supermassive black-hole binary and the surrounding accretion disc can both assist the binary inspiral and align the black-hole spins to the disc angular momentum. While binary migration is due to angular-momentum transfer within the circumbinary disc, the spin-alignment process is driven by the mass accreting onto each black hole. Mass transfer between different disc components thus couples the inspiral and the alignment process together. Mass is expected to leak through the cavity cleared by the binary, and preferentially accretes onto the lighter (secondary) black-hole which orbits closer to the disc edge. Low accretion rate onto the heavier (primary) black hole slows the alignment process down. We revisit the problem and develop a semi-analytical model to describe the coupling between gas-driven inspiral and spin alignment, finding that binaries with mass ratio q<~0.2 approach the gravitational-wave driven inspiral in differential misalignment: light secondaries prevent primaries ...

  2. The cosmic growth of the active black hole population at 1

    E-Print Network [OSTI]

    Schulze, A; Gavignaud, I; Schramm, M; Silverman, J; Merloni, A; Zamorani, G; Hirschmann, M; Mainieri, V; Wisotzki, L; Shankar, F; Fiore, F; Koekemoer, A M; Temporin, G

    2014-01-01T23:59:59.000Z

    We present a census of the active black hole population at 1black hole mass and Eddington ratio, employing a maximum likelihood fitting technique. The study of the active black hole mass function (BHMF) and the Eddington ratio distribution function (ERDF) allows to clearly disentangle the AGN downsizing phenomenon, present in the AGN luminosity function (AGN LF), into its physical processes of black hole mass downsizing and accretion rate evolution. We are utilizing type 1 AGN samples from 3 optical surveys (VVDS, zCOSMOS and SDSS), that cover a wide range of 3 dex in luminosity over our redshift interval of interest. We investigate the cosmic evolution of the AGN population as a function of AGN luminosity, black hole mass and accretion rate. Compared to z = 0 we find a distinct change in the shape of the BHMF and the ERDF, consistent with downsizing in black hole mass. The active fraction or duty cycle of type 1 AGN at z~1.5 is almost flat as...

  3. Ordered nanoporous carbon for increasing CO{sub 2} capture

    SciTech Connect (OSTI)

    Yoo, Hye-Min; Lee, Seul-Yi [Korea CCS R and D Center, Korea Institute of Energy Research, 152 Gajeongro, Yuseoung-gu, Daejeon 305-343 (Korea, Republic of); Department of Chemistry, Inha University, 100 Inharo, Nam-gu, Incheon 402-751 (Korea, Republic of); Park, Soo-Jin, E-mail: sjpark@inha.ac.kr [Korea CCS R and D Center, Korea Institute of Energy Research, 152 Gajeongro, Yuseoung-gu, Daejeon 305-343 (Korea, Republic of); Department of Chemistry, Inha University, 100 Inharo, Nam-gu, Incheon 402-751 (Korea, Republic of)

    2013-01-15T23:59:59.000Z

    Ordered nanoporous carbons (ONCs) were prepared using a soft-templating method. The prepared ONCs materials were subjected to a controlled carbonization temperature over the temperature range, 700-1000 Degree-Sign C, to increase the specific surface area and total pore volume of ordered nanoporous carbon followed by carbonization of the phenolic resin. ONCs materials synthesized at various carbonization temperatures were used as adsorbents to improve the CO{sub 2} adsorption efficiency. The surface properties of the ONCs materials were examined by X-ray photoelectron spectroscopy. The structural properties of the ONCs materials were analyzed by X-ray diffraction. The textural properties of the ONCs materials were examined using the N{sub 2}/77 K adsorption isotherms according to the Brunauer-Emmett-Teller equation. The CO{sub 2} adsorption capacity was measured by CO{sub 2} isothermal adsorption at 298 K/30 bar and 298 K/1 bar. The carbonization temperature was found to have a major effect on the CO{sub 2} adsorption capacity, resulting from the specific surface area and total pore volumes of the ONCs materials. - Graphical abstract: This schematic diagram described synthesis of ONCs. Highlights: Black-Right-Pointing-Pointer ONCs materials can be prepared readily using the direct-triblock-copolymer-templating method. Black-Right-Pointing-Pointer The distributions show that prominent development can be observed around the micro-pore region. Black-Right-Pointing-Pointer The soft-templating method provides opportunities for controlling the pore structure of ONCs. Black-Right-Pointing-Pointer From thermal power plants for CO2 capture by adsorption technology, is a new direction.

  4. Weighing black holes from zero to high redshift

    E-Print Network [OSTI]

    A. Marconi; D. Axon; R. Maiolino; T. Nagao; P. Pietrini; A. Robinson; G. Torricelli

    2008-09-02T23:59:59.000Z

    The application of the virial theorem provides a tool to estimate supermassive black hole (BH) masses in large samples of active galactic nuclei (AGN) with broad emission lines at all redshifts and luminosities, if the broad line region (BLR) is gravitationally bound. In this paper we discuss the importance of radiation forces on BLR clouds arising from the deposition of momentum by ionizing photons. Such radiation forces counteract gravitational ones and, if not taken into account, BH masses can be severely underestimated. We provide virial relations corrected for the effect of radiation pressure and we discuss their physical meaning and application. If these corrections to virial masses, calibrated with low luminosity objects, are extrapolated to high luminosities then the BLRs of most quasars might be gravitationally unbound. The importance of radiation forces in high luminosity objects must be thoroughly investigated to assess the reliability of quasar BH masses.

  5. Thermodynamics of regular black hole

    E-Print Network [OSTI]

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

    2008-09-21T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Manuela G. Rodrigues; Vilson T. Zanchin

    2015-02-02T23:59:59.000Z

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

  7. Sensitivity Comparison of Searches for Binary Black Hole Coalescences with Ground-based Gravitational-Wave Detectors

    E-Print Network [OSTI]

    Satya Mohapatra; Laura Cadonati; Sarah Caudill; James Clark; Chad Hanna; Sergey Klimenko; Chris Pankow; Ruslan Vaulin; Gabriele Vedovato; Salvatore Vitale

    2014-05-26T23:59:59.000Z

    Searches for gravitational-wave transients from binary black hole coalescences typically rely on one of two approaches: matched filtering with templates and morphology-independent excess power searches. Multiple algorithmic implementations in the analysis of data from the first generation of ground-based gravitational wave interferometers have used different strategies for the suppression of non-Gaussian noise transients, and targeted different regions of the binary black hole parameter space. In this paper we compare the sensitivity of three such algorithms: matched filtering with full coalescence templates, matched filtering with ringdown templates and a morphology-independent excess power search. The comparison is performed at a fixed false alarm rate and relies on Monte-carlo simulations of binary black hole coalescences for spinning, non-precessing systems with total mass 25-350 solar mass, which covers the parameter space of stellar mass and intermediate mass black hole binaries. We find that in the mass range of 25 -100 solar mass the sensitive distance of the search, marginalized over source parameters, is best with matched filtering to full waveform templates, to within 10 percent at a false alarm rate of 3 events per year. In the mass range of 100-350 solar mass, the same comparison favors the morphology-independent excess power search to within 20 percent. The dependence on mass and spin is also explored.

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

    E-Print Network [OSTI]

    Shun-Jin Wang

    2014-10-28T23:59:59.000Z

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

  9. Mass and Angular Momentum of Sgr A*

    E-Print Network [OSTI]

    B. Aschenbach

    2004-10-13T23:59:59.000Z

    For very fast spinning black holes with a>0.9953 the orbital velocity of a test particle unexpectly shows a positive radial gradient for low orbits, an effect of GR which has been overlooked so far. For a=0.99616 the maximum radial change of the orbital velocity equals the radial epicyclic frequency, which in turn is in a 1:3 resonance with the vertical epicyclic frequency. Application to Sgr A* using the quasi-periodic oscillations recently measured suggest that the mass of Sgr A* is 3.28 +/- 0.13 million solar masses.

  10. Scalar and Electromagnetic Quasinormal modes of Extended black hole in F(R) gravity

    E-Print Network [OSTI]

    Saneesh Sebastian; V. C. Kuriakose

    2014-08-05T23:59:59.000Z

    In this paper we study the scalar and electromagnetic perturbations of an extended black hole in F(R) gravity. The quasinormal modes in two cases are evaluated and studied their behavior by plotting graphs in each case. To study the quasinormal mode, we use the third order WKB method. The present study shows that the absolute value of imaginary part of complex quasinormal modes increases in both cases, thus the black hole is stable against these perturbations. As the mass of the scalar field increases the imaginary part of the frequency decreases. Thus damping slows down with increasing mass of the scalar field.

  11. Hairy black holes in N=2 gauged supergravity

    E-Print Network [OSTI]

    Federico Faedo; Dietmar Klemm; Masato Nozawa

    2015-05-22T23:59:59.000Z

    We construct black holes with scalar hair in a wide class of four-dimensional N=2 Fayet-Iliopoulos gauged supergravity theories that are characterized by a prepotential containing one free parameter. Considering the truncated model in which only a single real scalar survives, the theory is reduced to an Einstein-scalar system with a potential, which admits at most two AdS critical points and is expressed in terms of a real superpotential. Our solution is static, admits maximally symmetric horizons, asymptotically tends to AdS space corresponding to an extremum of the superpotential, but is disconnected from the Schwarzschild-AdS family. The condition under which the spacetime admits an event horizon is addressed for each horizon topology. It turns out that for hyperbolic horizons the black holes can be extremal. In this case, the near-horizon geometry is AdS_2 x H^2, where the scalar goes to the other, non-supersymmetric, critical point of the potential. Our solution displays fall-off behaviours different from the standard one, due to the fact that the mass parameter $m^2=-2/\\ell^2$ at the supersymmetric vacuum lies in a characteristic range $m^2_{BF}\\le m^2\\le m^2_{\\rm BF}+\\ell^{-2}$ for which the slowly decaying scalar field is also normalizable. Nevertheless, we identify a well-defined mass for our spacetime, following the prescription of Hertog and Maeda. Quite remarkably, the product of all horizon areas is not given in terms of the asymptotic cosmological constant alone, as one would expect in absence of electromagnetic charges and angular momentum. Our solution shows qualitatively the same thermodynamic behaviour as the Schwarzschild-AdS black hole, but the entropy is always smaller for a given mass and AdS curvature radius. We also find that our spherical black holes are unstable against radial perturbations.

  12. Organic carbon and non-refractory aerosol over the remote1 Southeast Pacific: oceanic and combustion sources2

    E-Print Network [OSTI]

    Wood, Robert

    1 Organic carbon and non-refractory aerosol over the remote1 Southeast Pacific: oceanic ratios between 0.25 and 0.40, and in some cases as high as 3.5. CO and12 black carbon (BC) measurements-salt particles30 from wave breaking and bubble bursting, as well as gas to particle conversion of vapors31

  13. Fishing in Black Holes

    E-Print Network [OSTI]

    A. Brotas

    2006-09-01T23:59:59.000Z

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

  14. CALIFORNIA CARBON SEQUESTRATION THROUGH

    E-Print Network [OSTI]

    CALIFORNIA ENERGY COMMISSION CARBON SEQUESTRATION THROUGH CHANGES IN LAND USE IN WASHINGTON. Carbon Sequestration Through Changes in Land Use in Washington: Costs and Opportunities. California for Terrestrial Carbon Sequestration in Oregon. Report to Winrock International. #12;ii #12;iii Preface

  15. Photophysics of carbon nanotubes

    E-Print Network [OSTI]

    Samsonidze, Georgii G

    2007-01-01T23:59:59.000Z

    This thesis reviews the recent advances made in optical studies of single-wall carbon nanotubes. Studying the electronic and vibrational properties of carbon nanotubes, we find that carbon nanotubes less than 1 nm in ...

  16. Black hole free energy during charged collapse: a numerical study

    E-Print Network [OSTI]

    Hugues Beauchesne; Ariel Edery

    2012-05-19T23:59:59.000Z

    We perform a numerical investigation of the thermodynamics during the collapse of a charged (complex) scalar field to a Reissner-Nordstr\\"om (RN) black hole in isotropic coordinates. Numerical work on gravitational collapse in isotropic coordinates has recently shown that the negative of the total Lagrangian approaches the Helmholtz free energy F= E-TS of a Schwarzschild black hole at late times of the collapse (where E is the black hole mass, T the temperature and S the entropy). The relevant thermodynamic potential for the RN black hole is the Gibbs free energy G=E-TS-$\\Phi_H$ Q where Q is the charge and $\\Phi_H$ the electrostatic potential at the outer horizon. In charged collapse, there is a large outgoing matter wave which prevents the exterior from settling quickly to a static state. However, the interior region is not affected significantly by the wave. We find numerically that the interior contribution to the Gibbs free energy is entirely gravitational and accumulates in a thin shell just inside the horizon. The entropy is gravitational in origin and one observes dynamically that it resides on the horizon. We also compare the numerical value of the interior Lagrangian to the expected analytical value of the interior Gibbs free energy for different initial states and we find that they agree to within 10-13%. The two values are approaching each other so that their difference decreases with more evolution time.

  17. Bulk emission of scalars by a rotating black hole

    E-Print Network [OSTI]

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

    2008-07-17T23:59:59.000Z

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

  18. Dynamically self-regular quantum harmonic black holes

    E-Print Network [OSTI]

    Spallucci, Euro

    2015-01-01T23:59:59.000Z

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

  19. Toward Zero Carbon Energy Production Toward Zero Carbon Energy Production

    E-Print Network [OSTI]

    Narasayya, Vivek

    #12;Toward Zero Carbon Energy Production Toward Zero Carbon Energy Production Toward Zero Carbon Energy Production Toward Zero Carbon Energy Production Toward Zero Carbon Energy Production Toward Zero Carbon Energy Production Toward Zero Carbon Energy Production Toward Zero Carbon Energy Production Toward

  20. Carbon Code Requirements for voluntary carbon sequestration projects

    E-Print Network [OSTI]

    Woodland Carbon Code Requirements for voluntary carbon sequestration projects ® Version 1.2 July trademark 10 3. Carbon sequestration 11 3.1 Units of carbon calculation 11 3.2 Carbon baseline 11 3.3 Carbon leakage 12 3.4 Project carbon sequestration 12 3.5 Net carbon sequestration 13 4. Environmental quality 14

  1. Kraft black liquor delivery systems

    SciTech Connect (OSTI)

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

    1990-02-01T23:59:59.000Z

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

  2. Energy Extraction from Boosted Black Holes: Penrose Process, Jets, and the Membrane at Infinity

    E-Print Network [OSTI]

    Penna, Robert F

    2015-01-01T23:59:59.000Z

    Numerical simulations indicate that black holes carrying linear momentum and/or orbital momentum can power jets. The jets extract the kinetic energy stored in the black hole's motion. This could provide an important electromagnetic counterpart to gravitational wave searches. We develop the theory underlying these jets. In particular, we derive the analogues of the Penrose process and the Blandford-Znajek jet power prediction for boosted black holes. The jet power we find is $(v/2M)^2 \\Phi^2/(4\\pi)$, where $v$ is the hole's velocity, $M$ is its mass, and $\\Phi$ is the magnetic flux. We show that energy extraction from boosted black holes is conceptually similar to energy extraction from spinning black holes. However, we highlight two key technical differences: in the boosted case, jet power is no longer defined with respect to a Killing vector, and the relevant notion of black hole mass is observer-dependent. We derive a new version of the membrane paradigm in which the membrane lives at infinity rather than t...

  3. Method of making carbon-carbon composites

    DOE Patents [OSTI]

    Engle, Glen B. (16716 Martincoit Rd., Poway, CA 92064)

    1993-01-01T23:59:59.000Z

    A process for making 2D and 3D carbon-carbon composites having a combined high crystallinity, high strength, high modulus and high thermal and electrical conductivity. High-modulus/high-strength mesophase derived carbon fibers are woven into a suitable cloth. Layers of this easily graphitizible woven cloth are infiltrated with carbon material to form green composites. The carbonized composite is then impregnated several times with pitch by covering the composite with hot pitch under pressure. The composites are given a heat treatment between each impregnant step to crack up the infiltrated carbon and allow additional pitch to enter the microstructure during the next impregnation cycle. The impregnated composites are then given a final heat treatment in the range 2500.degree. to 3100.degree. C. to fully graphitize the fibers and the matrix carbon. The composites are then infiltrated with pyrolytic carbon by chemical vapor deposition in the range 1000.degree. C. to 1300.degree. C. at a reduced. pressure.

  4. Carbon Fiber Technology Facility

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

    The Carbon Fiber Technology Facility is relevant in proving the scale- up of low-cost carbon fiber precursor materials and advanced manufacturing technologies * Significant...

  5. Motivating carbon dioxide | EMSL

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

    Motivating carbon dioxide Motivating carbon dioxide Released: April 17, 2013 Scientists show what it takes to get the potential fuel feedstock to a reactive spot on a model...

  6. Black holes at the centers of nearby dwarf galaxies

    SciTech Connect (OSTI)

    Moran, Edward C.; Shahinyan, Karlen; Sugarman, Hannah R.; Vélez, Darik O. [Astronomy Department, Wesleyan University, Middletown, CT 06459 (United States); Eracleous, Michael [Department of Astronomy and Astrophysics, and Institute for Gravitation and the Cosmos, The Pennsylvania State University, 525 Davey Lab, University Park, PA 16802 (United States)

    2014-12-01T23:59:59.000Z

    Using a distance-limited portion of the Sloan Digital Sky Survey (SDSS) Data Release 7, we have identified 28 active galactic nuclei (AGNs) in nearby (d?80 Mpc) low-mass, low-luminosity dwarf galaxies. The accreting objects at the galaxy centers are expected to be intermediate-mass black holes (IMBHs) with M{sub BH}?10{sup 6} M{sub ?}. The AGNs were selected using several optical emission-line diagnostics after careful modeling of the continuum present in the spectra. We have limited our survey to objects with spectral characteristics similar to those of Seyfert nuclei, excluding emission-line galaxies with ambiguous spectra that could be powered by stellar processes. Thus, as a set, the host galaxies in our sample are the least massive objects in the very local universe certain to contain central black holes. Our sample is dominated by narrow-line (type 2) AGNs, and it appears to have a much lower fraction of broad-line objects than that observed for luminous, optically selected Seyfert galaxies. Given our focus on the nearest objects included in the SDSS, our survey is more sensitive to low-luminosity emission than previous optical searches for AGNs in low-mass galaxies. The [O iii] ?5007 luminosities of the Seyfert nuclei in our sample have a median value of L{sub 5007}=2×10{sup 5} L{sub ?} and extend down to ?10{sup 4} L{sub ?}. Using published data for broad-line IMBH candidates, we have derived an [O iii] bolometric correction of log(L{sub bol}/L{sub 5007})=3.0±0.3, which is significantly lower than values obtained for high-luminosity AGNs. Applying this correction to our sample, we obtain minimum black hole mass estimates that fall mainly in the 10{sup 3} M{sub ?}–10{sup 4} M{sub ?} range, which is roughly where the predicted mass functions for different black hole seed formation scenarios overlap the most. In the stellar mass range that includes the bulk of the AGN host galaxies in our sample, we derive a lower limit on the AGN fraction of a few percent, indicating that active nuclei in dwarf galaxies are not as rare as previously thought.

  7. Carbon Capture (Carbon Cycle 2.0)

    ScienceCinema (OSTI)

    Smit, Berend

    2011-06-08T23:59:59.000Z

    Berend Smit speaks at the Carbon Cycle 2.0 kick-off symposium Feb. 3, 2010. We emit more carbon into the atmosphere than natural processes are able to remove - an imbalance with negative consequences. Carbon Cycle 2.0 is a Berkeley Lab initiative to provide the science needed to restore this balance by integrating the Labs diverse research activities and delivering creative solutions toward a carbon-neutral energy future. http://carboncycle2.lbl.gov/

  8. Jennifer Black Postdoctoral Research Associate

    E-Print Network [OSTI]

    Pennycook, Steve

    Microscopy Investigation of surface deformation of supercapacitor materials during charge-discharge of carbon-based aqueous supercapacitors Investigation of the mechanisms of self-discharge of supercapacitors

  9. Recovery of solvent and by-products from organosolv black liquor

    SciTech Connect (OSTI)

    Botello, J.I.; Gilarranz, M.A.; Rodriguez, F.; Oliet, M. [Univ. Complutense de Madrid (Spain). Dept. de Ingenieria Quimica] [Univ. Complutense de Madrid (Spain). Dept. de Ingenieria Quimica

    1999-09-01T23:59:59.000Z

    The recovery of alcohol and by-products from ethanol-water and methanol-water pulping liquors was studied. The recovery system proposed consists of three stages: black liquor flashing, lignin precipitation, and precipitation distillation of mother liquor. At the flash stage, 47 and 51% of the alcohol in the black liquor are recovered for ethanol and methanol processes, respectively. The lignin recovery yield at the precipitation stage is 67% for ethanol black liquor and 73% for methanol black liquor. The distillation of precipitation mother liquors enables recovery of 98% ethanol and 96% methanol from this stream as distillate, whereas the distillation residue contains significant amounts of sugars, furfural, and acetic acid that can be recovered. The study concludes with the overall mass balance for the recovery system proposed.

  10. The vacuum bubbles in de Sitter background and black hole pair creation

    E-Print Network [OSTI]

    Bum-Hoon Lee; Wonwoo Lee

    2009-10-07T23:59:59.000Z

    We study the possible types of the nucleation of vacuum bubbles. We classify vacuum bubbles in de Sitter background and present some numerical solutions. The thin-wall approximation is employed to obtain the nucleation rate and the radius of vacuum bubbles. With careful analysis we confirm that Parke's formula is also applicable to the large true vacuum bubbles. The nucleation of the false vacuum bubble in de Sitter background is also evaluated. The tunneling process in the potential with degenerate vacua is analyzed as the limiting cases of the large true vacuum bubble and false vacuum bubble. Next, we consider the pair creation of black holes in the background of bubble solutions. We obtain static bubble wall solutions of junction equation with black hole pair. The masses of created black holes are uniquely determined by the cosmological constant and surface tension on the wall. Finally, we obtain the rate of pair creation of black holes.

  11. Quantum Black Holes Effects on the Shape of Extensive Air Showers

    E-Print Network [OSTI]

    Nicusor Arsene; Lauretiu Ioan Caramete; Peter B. Denton; Octavian Micu

    2014-07-08T23:59:59.000Z

    We investigate the possibility to find a characteristic TeV scale quantum black holes decay signature in the data recorded by cosmic rays experiments. TeV black holes can be produced via the collisions of ultra high energetic protons (E > $10^18$ eV) with nucleons the from atmosphere. We focus on the case when the black holes decay into two particles moving in the forward direction in the Earth reference frame (back-to-back in the center of mass reference frame) and induce two overlapping showers. When reconstructing both the energy and the shape of the resultant air shower, there is a significant difference between showers induced only via standard model interactions and showers produced via the back-to-back decay of black holes as intermediate states.

  12. Thermal cycling effect on the nanoparticle distribution and specific heat of a carbonate eutectic with alumina nanoparticles

    E-Print Network [OSTI]

    Shankar, Sandhya

    2011-08-08T23:59:59.000Z

    The objective of this research was to measure the effect of thermal cycling on the nanoparticle distribution and specific heat of a nanocomposite material consisting of a eutectic of lithium carbonate and potassium carbonate and 1% by mass alumina...

  13. International black tea market integration and price discovery 

    E-Print Network [OSTI]

    Dharmasena, Kalu Arachchillage Senarath Dhananjaya Bandara

    2004-09-30T23:59:59.000Z

    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 use two statistical...

  14. Black hole mimickers: Regular versus singular behavior

    SciTech Connect (OSTI)

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

    2008-07-15T23:59:59.000Z

    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.

  15. Composite carbon foam electrode

    DOE Patents [OSTI]

    Mayer, S.T.; Pekala, R.W.; Kaschmitter, J.L.

    1997-05-06T23:59:59.000Z

    Carbon aerogels used as a binder for granulated materials, including other forms of carbon and metal additives, are cast onto carbon or metal fiber substrates to form composite carbon thin film sheets. The thin film sheets are utilized in electrochemical energy storage applications, such as electrochemical double layer capacitors (aerocapacitors), lithium based battery insertion electrodes, fuel cell electrodes, and electrocapacitive deionization electrodes. The composite carbon foam may be formed by prior known processes, but with the solid particles being added during the liquid phase of the process, i.e. prior to gelation. The other forms of carbon may include carbon microspheres, carbon powder, carbon aerogel powder or particles, graphite carbons. Metal and/or carbon fibers may be added for increased conductivity. The choice of materials and fibers will depend on the electrolyte used and the relative trade off of system resistivity and power to system energy. 1 fig.

  16. Composite carbon foam electrode

    DOE Patents [OSTI]

    Mayer, Steven T. (San Leandro, CA); Pekala, Richard W. (Pleasant Hill, CA); Kaschmitter, James L. (Pleasanton, CA)

    1997-01-01T23:59:59.000Z

    Carbon aerogels used as a binder for granularized materials, including other forms of carbon and metal additives, are cast onto carbon or metal fiber substrates to form composite carbon thin film sheets. The thin film sheets are utilized in electrochemical energy storage applications, such as electrochemical double layer capacitors (aerocapacitors), lithium based battery insertion electrodes, fuel cell electrodes, and electrocapacitive deionization electrodes. The composite carbon foam may be formed by prior known processes, but with the solid particles being added during the liquid phase of the process, i.e. prior to gelation. The other forms of carbon may include carbon microspheres, carbon powder, carbon aerogel powder or particles, graphite carbons. Metal and/or carbon fibers may be added for increased conductivity. The choice of materials and fibers will depend on the electrolyte used and the relative trade off of system resistivty and power to system energy.

  17. Estimating parameters of binary black holes from gravitational-wave observations of their inspiral, merger and ringdown

    E-Print Network [OSTI]

    Archisman Ghosh; Walter Del Pozzo; Parameswaran Ajith

    2015-05-21T23:59:59.000Z

    We characterize the expected statistical errors with which the parameters of black-hole binaries can be measured from gravitational-wave (GW) observations of their inspiral, merger and ringdown by a network of second-generation ground-based GW observatories. We simulate a population of black-hole binaries with uniform distribution of component masses in the interval $(3,80)~M_\\odot$, distributed uniformly in comoving volume, with isotropic orientations. From signals producing signal-to-noise ratio $\\geq 5$ in at least two detectors, we estimate the posterior distributions of the binary parameters using the Bayesian parameter estimation code LALInference. The GW signals will be redshifted due to the cosmological expansion and we measure only the "redshifted" masses. By assuming a cosmology, it is possible to estimate the gravitational masses by inferring the redshift from the measured posterior of the luminosity distance. We find that the measurement of the gravitational masses will be in general dominated by the error in measuring the luminosity distance. In spite of this, the component masses of more than $50\\%$ of the population can be measured with accuracy better than $\\sim 25\\%$ using the Advanced LIGO-Virgo network. Additionally, the mass of the final black hole can be measured with median accuracy $\\sim 18\\%$. Spin of the final black hole can be measured with median accuracy $\\sim 5\\% ~(17\\%)$ for binaries with non-spinning (aligned-spin) black holes. Additional detectors in Japan and India significantly improve the accuracy of sky localization, and moderately improve the estimation of luminosity distance, and hence, that of all mass parameters. We discuss the implication of these results on the observational evidence of intermediate-mass black holes and the estimation of cosmological parameters using GW observations.

  18. Call for Papers and Panels Unleashing the Black Erotic

    E-Print Network [OSTI]

    Kunkle, Tom

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

  19. Heat Engine of black holes

    E-Print Network [OSTI]

    Sadeghi, J

    2015-01-01T23:59:59.000Z

    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.

  20. Heat Engine of black holes

    E-Print Network [OSTI]

    J. Sadeghi; Kh. Jafarzade

    2015-04-29T23:59:59.000Z

    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.

  1. Energy on black hole spacetimes

    E-Print Network [OSTI]

    Alejandro Corichi

    2012-07-18T23:59:59.000Z

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

  2. The runaway instability of thick discs around black holes. II. Non constant angular momentum discs

    E-Print Network [OSTI]

    Frederic Daigne; Jose A. Font

    2003-11-28T23:59:59.000Z

    We present results from a comprehensive number of relativistic, time-dependent, axisymmetric simulations of the runaway instability of non-constant angular momentum thick discs around black holes. This second paper extends earlier results where only constant angular momentum discs were considered. All relevant aspects of the theory of stationary thick discs around rotating black holes, necessary to build the initial state in our simulations, are presented in great detail. The angular momentum of the discs is assumed to increase outwards with the radial distance according to a power law. The main simplifying assumptions of our approach are not to include magnetic fields and self-gravity in the discs. Furthermore, the dynamics of the spacetime is accounted for by computing the transfer of mass and angular momentum from the disc to the black hole through the event horizon : the evolution of the central black hole is assumed to follow a sequence of Kerr black holes of increasing mass and spin. In agreement with previous results based on stationary models we find that by allowing the mass and the spin of the black hole to grow, constant angular momentum discs rapidly become unstable on a dynamical timescale. The comparison with the results of paper I shows that the effect of the angular momentum transfer from the torus to the black hole is to make constant angular momentum discs less unstable, increasing the timescale of the instability. However, we find that non-constant angular momentum discs are dramatically stabilized for very small values of the angular momentum slope. Our time-dependent simulations confirm, thus, the predictions of stationary studies concerning the stabilizing effect of non-constant angular momentum distributions.

  3. Numerical Modeling of Charged Black Holes with Massive Dilaton

    E-Print Network [OSTI]

    T. L. Boyadjiev; P. P. Fiziev

    2003-11-28T23:59:59.000Z

    In this paper the static, spherically symmetric and electrically charged black hole solutions in Einstein-Born-Infeld gravity with massive dilaton are investigated numerically. The Continuous Analog of Newton Method (CANM) is used to solve the corresponding nonlinear multipoint boundary value problems (BVPs). The linearized BVPs are solved numerically by means of collocation scheme of fourth order. A special class of solutions are the extremal ones. We show that the extremal horizons within the framework of the model satisfy some nonlinear system of algebraic equations. Depending on the charge $q$ and dilaton mass $\\gamma$, the black holes can have no more than three horizons. This allows us to construct some Hermite polynomial of third order. Its real roots describe the number, the type and other characteristics of the horizons.

  4. Black Holes with Quantum Massive Spin-2 Hair

    E-Print Network [OSTI]

    Gia Dvali

    2006-05-31T23:59:59.000Z

    We show that black holes can posses a long range quantum mechanical hair associated with a massive spin-2 field, which can be detected by a stringy generalization of the Aharovon-Bohm effect, in which a string loop lassoes the black hole. The long distance effect persist for arbitrarily high mass of the spin-2 field. An analogous effect is exhibited by a massive antisymmetric two-form field. We make a close parallel between the two and the ordinary Aharonov-Bohm phenomenon, and also show that in the latter case the effect can be experienced even by the electrically-neutral particles, provided some boundary terms are added to the action.

  5. Black Literary Suite: Kansas Authors Edition

    E-Print Network [OSTI]

    Wiggins, Meredith Joan

    2015-03-04T23:59:59.000Z

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

  6. Maximal spin and energy conversion efficiency in a symbiotic system of black hole, disk and jet

    E-Print Network [OSTI]

    Zoltán Kovács; László Á. Gergely; Peter L. Biermann

    2011-10-13T23:59:59.000Z

    We study a combined model of black hole - accretion disk - magnetosphere - jet symbiosis, applicable for supermassive black holes. We quantify the mass and spin evolution and we analyze how the limiting value of the spin parameter and the conversion efficiency of accreted mass into radiation depend on the interplay of electromagnetic radiation reaction, magnetosphere characteristics and truncation radius of radiation. The dominant effect comes from the closed magnetic field line region, which reduces the spin limit to values ~0.89 (instead ~0.99 in its absence). Therefore observations on black hole spins could favour or disfavour the existence of the closed magnetic field line region (or its coupling to the disk). We also find that the suppression of radiation from the innermost part of the accretion disk, inferred from observations, and a collimated jet both increase the spin limit and the energy conversion efficiency.

  7. Time-dependent models of two-phase accretion discs around black holes

    E-Print Network [OSTI]

    M. Mayer; J. E. Pringle

    2006-12-28T23:59:59.000Z

    We present time-dependent simulations of a two-phase accretion flow around a black hole. The accretion flow initially is composed of an optically thick and cool disc close to the midplane, while on top and below the disc there is a hot and optically thin corona. We consider several interaction mechanisms as heating of the disc by the corona and Compton cooling of the corona by the soft photons of the disc. Mass and energy can be exchanged between the disc and the corona due to thermal conduction. For the course of this more exploratory work, we limit ourselves to one particular model for a stellar mass black hole accreting at a low accretion rate. We confirm earlier both theoretical and observational results which show that at low accretion rates the disc close to the black hole cannot survive and is evaporated. Given the framework of this model, we now can follow through this phase of disc evaporation time dependently.

  8. Dirac quasinormal frequencies of Schwarzschild-anti-de Sitter and Reissner-Nordstrom-anti-de Sitter black holes

    SciTech Connect (OSTI)

    Jing Jiliang; Pan Qiyuan [Institute of Physics and Department of Physics, Hunan Normal University, Changsha, Hunan 410081 (China)

    2005-06-15T23:59:59.000Z

    We investigate the Dirac quasinormal modes (QNMs) of the Schwarzschild-anti-de Sitter and Reissner-Nordstrom-anti-de Sitter (SAdS/RNAdS) black holes using Horowitz-Hubeny approach. For large black holes, the fundamental QNMs are the linear functions of the Hawking temperature, and the slope of the lines decreases as the charge increases. For intermediate and small SAdS black holes, the real part of the fundamental QNMs approximates a temperature curve but the corresponding imaginary part is almost a linear function of the radius of the black hole. The quasinormal frequencies for high overtones become evenly spaced and the spacings are related to the mass and charge of the black hole. We also study the relation between QNMs and angular quantum number and find that the quasinormal frequencies increase as the angular quantum number increases.

  9. Dynamics of Particles Around a Schwarzschild-like Black Hole in the Presence of Quintessence and Magnetic Field

    E-Print Network [OSTI]

    Mubasher Jamil; Saqib Hussain; Bushra Majeed

    2015-01-21T23:59:59.000Z

    We investigate the dynamics of a neutral and a charged particle around a static and spherically symmetric black hole in the presence of quintessence matter and external magnetic field. We explore the conditions under which the particle moving around the black hole could escape to infinity after colliding with another particle. The innermost stable circular orbit (ISCO) for the particles are studied in detail. Mainly the dependence of ISCO on dark energy and on the presence of external magnetic field in the vicinity of black hole is discussed. By using the Lyapunov exponent, we compare the stabilities of the orbits of the particles in the presence and absence of dark energy and magnetic field. The expressions for the center of mass energies of the colliding particles near the horizon of the black hole are derived. The effective force on the particles due to dark energy and magnetic field in the vicinity of black hole is also discussed.

  10. A Novel Approach to Mineral Carbonation: Enhancing Carbonation While Avoiding Mineral Pretreatment Process Cost

    SciTech Connect (OSTI)

    Andrew V. G. Chizmeshya; Michael J. McKelvy; Kyle Squires; Ray W. Carpenter; Hamdallah Bearat

    2007-06-21T23:59:59.000Z

    Known fossil fuel reserves, especially coal, can support global energy demands for centuries to come, if the environmental problems associated with CO{sub 2} emissions can be overcome. Unlike other CO{sub 2} sequestration candidate technologies that propose long-term storage, mineral sequestration provides permanent disposal by forming geologically stable mineral carbonates. Carbonation of the widely occurring mineral olivine (e.g., forsterite, Mg{sub 2}SiO{sub 4}) is a large-scale sequestration process candidate for regional implementation, which converts CO{sub 2} into the environmentally benign mineral magnesite (MgCO{sub 3}). The primary goal is cost-competitive process development. As the process is exothermic, it inherently offers low-cost potential. Enhancing carbonation reactivity is key to economic viability. Recent studies at the U.S. DOE Albany Research Center have established that aqueous-solution carbonation using supercritical CO{sub 2} is a promising process; even without olivine activation, 30-50% carbonation has been achieved in an hour. Mechanical activation (e.g., attrition) has accelerated the carbonation process to an industrial timescale (i.e., near completion in less than an hour), at reduced pressure and temperature. However, the activation cost is too high to be economical and lower cost pretreatment options are needed. We have discovered that robust silica-rich passivating layers form on the olivine surface during carbonation. As carbonation proceeds, these passivating layers thicken, fracture and eventually exfoliate, exposing fresh olivine surfaces during rapidly-stirred/circulating carbonation. We are exploring the mechanisms that govern carbonation reactivity and the impact that (1) modeling/controlling the slurry fluid-flow conditions, (2) varying the aqueous ion species/size and concentration (e.g., Li+, Na+, K+, Rb+, Cl-, HCO{sub 3}{sup -}), and (3) incorporating select sonication offer to enhance exfoliation and carbonation. Thus far, we have succeeded in nearly doubling the extent of carbonation observed compared with the optimum procedure previously developed by the Albany Research Center. Aqueous carbonation reactivity was found to be a strong function of the ionic species present and their aqueous activities, as well as the slurry fluid flow conditions incorporated. High concentration sodium, potassium, and sodium/potassium bicarbonate aqueous solutions have been found to be the most effective solutions for enhancing aqueous olivine carbonation to date. Slurry-flow modeling using Fluent indicates that the slurry-flow dynamics are a strong function of particle size and mass, suggesting that controlling these parameters may offer substantial potential to enhance carbonation. During the first project year we developed a new sonication exfoliation apparatus with a novel sealing system to carry out the sonication studies. We also initiated investigations to explore the potential that sonication may offer to enhance carbonation reactivity. During the second project year, we extended our investigations of the effects of sonication on the extent of carbonation as a function of the following parameters: particle size distribution, the mass of solid reactant, volume fraction of aqueous solution present, sonication power, time, temperature, and CO{sub 2} pressure. To date, none of the conditions investigated have significantly enhanced carbonation. Mechanistic investigations of the stirred ({approx}1,500 rpm) aqueous olivine carbonation process indicate the carbonation process involves both incongruent magnesium dissolution and silica precipitation, which results in robust silica-rich passivating layer formation. Secondary ion mass spectrometry observation of H within the passivating layer that forms during static carbonation suggests 2H{sup +}/Mg{sup 2+} ion exchange is associated with incongruent dissolution. Apparently, H{sub 2}O forms at or near the olivine/passivating-layer interface during the process and diffuses out through the passivating layers during the carbonation reaction. This is

  11. Introduction to Black Hole Evaporation

    E-Print Network [OSTI]

    Pierre-Henry Lambert

    2014-01-16T23:59:59.000Z

    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.

  12. Hurricane Katrina's Carbon Footprint on U.S. Gulf Coast Forests

    E-Print Network [OSTI]

    Chambers, Jeff

    Hurricane Katrina's Carbon Footprint on U.S. Gulf Coast Forests Jeffrey Q. Chambers,1 * Jeremy I carbon sink is an increase in disturbance frequency and intensity (4), which transfers bio- mass from and lower biomass stocks (5). Here, we quantify hurricane Katrina's carbon impact on Gulf Coast forests

  13. Black Holes in Galaxy Mergers: Evolution of Quasars

    E-Print Network [OSTI]

    Philip F. Hopkins; Lars Hernquist; Thomas J. Cox; Tiziana Di Matteo; Paul Martini; Brant Robertson; Volker Springel

    2005-06-13T23:59:59.000Z

    Based on numerical simulations of gas-rich galaxy mergers, we discuss a model in which quasar activity is tied to the self-regulated growth of supermassive black holes in galaxies. Nuclear inflow of gas attending a galaxy collision triggers a starburst and feeds black hole growth, but for most of the duration of the starburst, the black hole is heavily obscured by surrounding gas and dust which limits the visibility of the quasar, especially at optical and UV wavelengths. Eventually, feedback energy from accretion heats the gas and expels it in a powerful wind, leaving a 'dead quasar'. Between buried and dead phases there is a window during which the galaxy would be seen as a luminous quasar. Because the black hole mass, radiative output, and distribution of obscuring gas and dust all evolve strongly with time, the duration of this phase of observable quasar activity depends on both the waveband and imposed luminosity threshold. We determine the observed and intrinsic lifetimes as a function of luminosity and frequency, and calculate observable lifetimes ~10 Myr for bright quasars in the optical B-band, in good agreement with empirical estimates and much smaller than the black hole growth timescales ~100 Myr, naturally producing a substantial population of 'buried' quasars. However, observed and intrinsic energy outputs converge in the IR and hard X-ray bands as attenuation becomes weaker and chances of observation greatly increase. We obtain the distribution of column densities along sightlines in which the quasar is seen above a given luminosity, and find that our result agrees remarkably well with observed estimates of the column density distribution from the SDSS for appropriate luminosity thresholds. (Abridged)

  14. The lifetime problem of evaporating black holes: mutiny or resignation

    E-Print Network [OSTI]

    Carlos Barceló; Raúl Carballo-Rubio; Luis J. Garay; Gil Jannes

    2015-02-09T23:59:59.000Z

    It is logically possible that regularly evaporating black holes exist in nature. In fact, the prevalent theoretical view is that these are indeed the real objects behind the curtain in astrophysical scenarios. There are several proposals for regularizing the classical singularity of black holes so that their formation and evaporation do not lead to information-loss problems. One characteristic is shared by most of these proposals: these regularly evaporating black holes present long-lived trapping horizons, with absolutely enormous evaporation lifetimes in whatever measure. Guided by the discomfort with these enormous and thus inaccessible lifetimes, we elaborate here on an alternative regularization of the classical singularity, previously proposed by the authors in an emergent gravity framework, which leads to a completely different scenario. In our scheme the collapse of a stellar object would result in a genuine time-symmetric bounce, which in geometrical terms amounts to the connection of a black-hole geometry with a white-hole geometry in a regular manner. The two most differential characteristics of this proposal are: i) the complete bouncing geometry is a solution of standard classical general relativity everywhere except in a transient region that necessarily extends beyond the gravitational radius associated with the total mass of the collapsing object; and ii) the duration of the bounce as seen by external observers is very brief (fractions of milliseconds for neutron-star-like collapses). This scenario motivates the search for new forms of stellar equilibrium different from black holes. In a brief epilogue we compare our proposal with a similar geometrical setting recently proposed by Haggard and Rovelli.

  15. Hawking Emission and Black Hole Thermodynamics

    E-Print Network [OSTI]

    Don N. Page

    2006-12-18T23:59:59.000Z

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

  16. Research Summary Carbon Additionality

    E-Print Network [OSTI]

    of the quality assurance of emissions reduction and carbon sequestration activities, but remains a source of muchResearch Summary Carbon Additionality Additionality is widely considered to be a core aspect controversy in national carbon accounting, international regulatory frameworks and carbon markets. A review

  17. Acetylenic carbon allotrope

    DOE Patents [OSTI]

    Lagow, R.J.

    1998-02-10T23:59:59.000Z

    A fourth allotrope of carbon, an acetylenic carbon allotrope, is described. The acetylenic carbon allotropes of the present invention are more soluble than the other known carbon allotropes in many common organic solvents and possesses other desirable characteristics, e.g. high electron density, ability to burn cleanly, and electrical conductive properties. Many uses for this fourth allotrope are described herein. 17 figs.

  18. Carbon Monoxide Environmental Public

    E-Print Network [OSTI]

    The National Workgroup on Carbon Monoxide Surveillance Formed in April 2005 Membership: EPHT grantees Academic

  19. The Woodland Carbon Code

    E-Print Network [OSTI]

    The Woodland Carbon Code While society must continue to make every effort to reduce greenhouse gas a role by removing carbon dioxide from the atmosphere. The potential of woodlands to soak up carbon to help compensate for their carbon emissions. But before investing in such projects, people want to know

  20. Mesoporous carbon materials

    SciTech Connect (OSTI)

    Dai, Sheng; Fulvio, Pasquale Fernando; Mayes, Richard T.; Wang, Xiqing; Sun, Xiao-Guang; Guo, Bingkun

    2014-09-09T23:59:59.000Z

    A conductive mesoporous carbon composite comprising conductive carbon nanoparticles contained within a mesoporous carbon matrix, wherein the conductive mesoporous carbon composite possesses at least a portion of mesopores having a pore size of at least 10 nm and up to 50 nm, and wherein the mesopores are either within the mesoporous carbon matrix, or are spacings delineated by surfaces of said conductive carbon nanoparticles when said conductive carbon nanoparticles are fused with each other, or both. Methods for producing the above-described composite, devices incorporating them (e.g., lithium batteries), and methods of using them, are also described.