WorldWideScience

Sample records for black hole mass

  1. Black-Hole Mass Measurements

    DEFF Research Database (Denmark)

    Vestergaard, Marianne

    2004-01-01

    The applicability and apparent uncertainties of the techniques currently available for measuring or estimating black-hole masses in AGNs are briefly summarized.......The applicability and apparent uncertainties of the techniques currently available for measuring or estimating black-hole masses in AGNs are briefly summarized....

  2. Intermediate-Mass Black Holes

    CERN Document Server

    Miller, M C

    2004-01-01

    The mathematical simplicity of black holes, combined with their links to some of the most energetic events in the universe, means that black holes are key objects for fundamental physics and astrophysics. Until recently, it was generally believed that black holes in nature appear in two broad mass ranges: stellar-mass (roughly 3-20 solar masses), which are produced by the core collapse of massive stars, and supermassive (millions to billions of solar masses), which are found in the centers of galaxies and are produced by a still uncertain combination of processes. In the last few years, however, evidence has accumulated for an intermediate-mass class of black holes, with hundreds to thousands of solar masses. If such objects exist they have important implications for the dynamics of stellar clusters, the formation of supermassive black holes, and the production and detection of gravitational waves. We review the evidence for intermediate-mass black holes and discuss future observational and theoretical work t...

  3. Black Holes with Zero Mass

    CERN Document Server

    Nucamendi, U; Nucamendi, Ulises; Sudarsky, Daniel

    2000-01-01

    We consider the spacetimes corresponding to static Global Monopoles with interior boundaries corresponding to a Black Hole Horizon and analyze the behavior of the appropriate ADM mass as a function of the horizon radius r_H. We find that for small enough r_H, this mass is negative as in the case of the regular global monopoles, but that for large enough r_H the mass becomes positive encountering an intermediate value for which we have a Black Hole with zero ADM mass.

  4. Black-hole masses of distant quasars

    DEFF Research Database (Denmark)

    Vestergaard, Marianne

    2011-01-01

    A brief overview of the methods commonly used to determine or estimate the black hole mass in quiescent or active galaxies is presented and it is argued that the use of mass-scaling relations is both a reliable and the preferred method to apply to large samples of distant quasars. The method uses...... that the black hole masses are very large, of order 1 to 10 billion solar masses, even at the highest redshifts of 4 to 6. The black holes must build up their mass very fast in the early universe. Yet they do not grow much larger than that: a maximum mass of about 10 billion solar masses is also observed....... Preliminary mass functions of active black holes are presented for several quasar samples, including the Sloan Digital Sky Survey. Finally, common concerns related to the application of the mass scaling relations, especially for high redshift quasars, are briefly discussed....

  5. Central black hole masses of galaxies

    Institute of Scientific and Technical Information of China (English)

    樊军辉

    2003-01-01

    In this paper, the stellar velocity dispersions in the host galaxies are used to estimate the central black hole masses for a sample of elliptical galaxies. We find that the central black hole masses are in the range of 10(5.5-9.5) M(○). Based on the estimated masses in this paper and those by Woo & Urry (2002) and the measured host galaxy absolute magnitude,a relation, log(MBH/M(○)) = -(0.25 ± 4.3 × 10-3)MR + (2.98 4 0.208) is found for central black hole mass and the host galaxy magnitude. Some discussions are presented.

  6. Estimating Black Hole Masses of Blazars

    Indian Academy of Sciences (India)

    Xue-Bing Wu; F. K. Liu; M. Z. Kong; R. Wang; J. L. Han

    2011-03-01

    Estimating black hole masses of blazars is still a big challenge. Because of the contamination of jets, using the previously suggested size–continuum luminosity relation can overestimate the broad line region (BLR) size and black hole mass for radio-loud AGNs, including blazars. We propose a new relation between the BLR size and emission line luminosity and present evidences for using it to get more accurate black hole masses of radio-loud AGNs. For extremely radio-loud AGNs such as blazars with weak/absent emission lines, we suggest the use of fundamental plane relation of their elliptical host galaxies to estimate the central velocity dispersions and black hole masses, if their velocity dispersions are not known but the host galaxies can be mapped. The black hole masses of some well-known blazars, such as OJ 287, AO 0235+164 and 3C 66B are obtained using these two methods and the – relation. The implications of their black hole masses on other related studies are also discussed.

  7. Mass of a black hole firewall.

    Science.gov (United States)

    Abramowicz, M A; Kluźniak, W; Lasota, J-P

    2014-03-07

    Quantum entanglement of Hawking radiation has been supposed to give rise to a Planck density "firewall" near the event horizon of old black holes. We show that Planck density firewalls are excluded by Einstein's equations for black holes of mass exceeding the Planck mass. We find an upper limit of 1/(8πM) to the surface density of a firewall in a Schwarzschild black hole of mass M, translating for astrophysical black holes into a firewall density smaller than the Planck density by more than 30 orders of magnitude. A strict upper limit on the firewall density is given by the Planck density times the ratio M(Pl)/(8πM).

  8. Low-mass black holes as the remnants of primordial black hole formation

    CERN Document Server

    Greene, Jenny E

    2012-01-01

    This article documents our ongoing search for the elusive "intermediate-mass" black holes. These would bridge the gap between the approximately ten solar mass "stellar-mass" black holes that are the end-product of the life of a massive star, and the "supermassive" black holes with masses of millions to billions of solar masses found at the centers of massive galaxies. The discovery of black holes with intermediate mass is the key to understanding whether supermassive black holes can grow from stellar-mass black holes, or whether a more exotic process accelerated their growth only hundreds of millions of years after the Big Bang. Here we focus on searches for black holes with masses of 10^4-10^6 solar masses that are found at galaxy centers. We will refer to black holes in this mass range as "low-mass" black holes, since they are at the low-mass end of supermassive black holes. We review the searches for low-mass black holes to date and show tentative evidence, from the number of low-mass black holes that are ...

  9. Investigating stellar-mass black hole kicks

    CERN Document Server

    Repetto, Serena; Sigurdsson, Steinn

    2012-01-01

    We investigate whether stellar-mass black holes have to receive natal kicks in order to explain the observed distribution of low-mass X-ray binaries containing black holes within our Galaxy. Such binaries are the product of binary evolution, where the massive primary has exploded forming a stellar-mass black hole, probably after a common envelope phase where the system contracted down to separations of order 10-30 Rsun. We perform population synthesis calculations of these binaries, applying both kicks due to supernova mass-loss and natal kicks to the newly-formed black hole. We then integrate the trajectories of the binary systems within the Galactic potential. We find that natal kicks are in fact necessary to reach the large distances above the Galactic plane achieved by some binaries. Further, we find that the distribution of natal kicks would seem to be similar to that of neutron stars, rather than one where the kick velocities are reduced by the ratio of black hole to neutron-star mass (i.e. where the ki...

  10. Low-mass black holes as the remnants of primordial black hole formation.

    Science.gov (United States)

    Greene, Jenny E

    2012-01-01

    Bridging the gap between the approximately ten solar mass 'stellar mass' black holes and the 'supermassive' black holes of millions to billions of solar masses are the elusive 'intermediate-mass' black holes. Their discovery is key to understanding whether supermassive black holes can grow from stellar-mass black holes or whether a more exotic process accelerated their growth soon after the Big Bang. Currently, tentative evidence suggests that the progenitors of supermassive black holes were formed as ∼10(4)-10(5) M(⊙) black holes via the direct collapse of gas. Ongoing searches for intermediate-mass black holes at galaxy centres will help shed light on this formation mechanism.

  11. Black hole bombs and photon mass bounds

    CERN Document Server

    Pani, Paolo; Gualtieri, Leonardo; Berti, Emanuele; Ishibashi, Akihiro

    2012-01-01

    Generic extensions of the standard model predict the existence of ultralight bosonic degrees of freedom. Several ongoing experiments are aimed at detecting these particles or constraining their mass range. Here we show that massive vector fields around rotating black holes can give rise to a strong superradiant instability which extracts angular momentum from the hole. The observation of supermassive spinning black holes imposes limits on this mechanism. We show that current supermassive black hole spin estimates provide the tightest upper limits on the mass of the photon (mv<4x10^{-20} eV according to our most conservative estimate), and that spin measurements for the largest known supermassive black holes could further lower this bound to mv<10^{-22} eV. Our analysis relies on a novel framework to study perturbations of rotating Kerr black holes in the slow-rotation regime, that we developed up to second order in rotation, and that can be extended to other spacetime metrics and other theories.

  12. Low-mass black holes as the remnants of primordial black hole formation

    OpenAIRE

    Greene, Jenny E.

    2012-01-01

    This article documents our ongoing search for the elusive "intermediate-mass" black holes. These would bridge the gap between the approximately ten solar mass "stellar-mass" black holes that are the end-product of the life of a massive star, and the "supermassive" black holes with masses of millions to billions of solar masses found at the centers of massive galaxies. The discovery of black holes with intermediate mass is the key to understanding whether supermassive black holes can grow from...

  13. Astronomy: Intermediate-mass black hole found

    Science.gov (United States)

    Gültekin, Kayhan

    2017-02-01

    The existence of medium-sized black holes has long been debated. Such an object has now been discovered in the centre of a dense cluster of stars, potentially enhancing our understanding of all black holes. See Letter p.203

  14. Measurement of Black Hole Mass Radio-Loud Quasars

    Indian Academy of Sciences (India)

    Cheng-Yue Su; Z.-F. Chen; R.-L. He; C.-H. Zhang; T.-T. Wang

    2011-03-01

    In this work, we construct a sample of 1585 radio-loud quasars to measure their black hole masses using broad emission lines. We compare our black hole masses with the virial black hole masses measured by Shen et al. (2010).We find that there is a large deviation between them if our black hole mass is measured from the CIV broad emission line. Whereas, if our black hole mass is measured from broad emission line of Mg II or H, both the values are consistent.

  15. Estimation of Black Hole Masses from Steep Spectrum Radio Quasars

    Indian Academy of Sciences (India)

    Ye Chen; Zhi-Fu Chen; Yi-Ping Qin; You-Bing Li

    2011-03-01

    In this work, we employ a sample of 185 steep-spectrum radio quasars (SSRQs) to estimate their black hole masses from broad emission lines. Our black hole masses are compared with the virial black hole masses estimated by Shen (2010). We find that there is a large deviation between the two kinds of values if the black hole masses are estimated from broad emission line of CIV. However, both values are in agreement if the black hole masses are estimated from broad emission line of MgII or H.

  16. Stellar-Mass Black Holes and their Progenitors

    NARCIS (Netherlands)

    Miller, J.; Uttley, [No Value; Nandra, [No Value; Barret, [No Value; Matt, [No Value; Paerels, [No Value; Mendez, [No Value; Diaz-Trigo, [No Value; Cappi, [No Value; Kitamoto, [No Value; Nowak, [No Value; Wilms, [No Value; Rothschild, [No Value; Smith, [No Value; Weisskopf, [No Value; Terashima, [No Value; Ueda, [No Value

    2009-01-01

    If a black hole has a low spin value, it must double its mass to reach a high spin parameter (Volonteri et al. 2005). Although this is easily accomplished through mergers or accretion in the case of supermassive black holes in galactic centers, it is impossible for stellar-mass black holes in X-ray

  17. Mechanism for the Suppression of Intermediate-Mass Black Holes

    OpenAIRE

    Dokuchaev, V. I.; Eroshenko, Yu. N.; Rubin, S G; Samarchenko, D. A.

    2010-01-01

    A model for the formation of supermassive primordial black holes in galactic nuclei with the simultaneous suppression of the formation of intermediate-mass black holes is presented. A bimodal mass function for black holes formed through phase transitions in a model with a "Mexican hat" potential has been found. The classical motion of the phase of a complex scalar field during inflation has been taken into account. Possible observational manifestations of primordial black holes in galaxies an...

  18. Theoretical reevaluations of black hole mass -- bulge mass relation - I. Influences of the seed black hole mass

    CERN Document Server

    Shirakata, Hikari; Okamoto, Takashi; Makiya, Ryu; Ishiyama, Tomoaki; Matsuoka, Yoshiki; Nagashima, Masahiro; Enoki, Motohiro; Oogi, Taira; Kobayashi, Masakazu A R

    2016-01-01

    We show influences of the mass of seed black holes on black hole mass -- bulge mass relation at z ~ 0 by using a semi-analytic model of galaxy formation combined with large cosmological N-body simulations. We constrain our model to reproduce observed properties of galaxies at z ~ 0. Similar to other semi-analytic models, we place a seed black hole immediately after a galaxy forms. When we set the seed black hole mass to 10^5 M_sun, we find that the model result becomes inconsistent with recent observational results of black hole mass -- bulge mass relation for dwarf galaxies. Namely, the model predicts that bulges with ~ 10^9 M_sun harbor black holes more massive than observed. On the other hand, when we employ seed black holes with 10^3 M_sun or randomly choose their masses in the range of 10^{3-5} M_sun, the black hole mass -- bulge mass relation obtained from these models are consistent with observational results including dispersions. We find that to obtain more stringent restrictions of the mass of seed ...

  19. Black hole masses of BL Lac objects

    OpenAIRE

    J. K. Kotilainen; Falomo, R.; Treves, A.

    2002-01-01

    The correlation between black hole mass M(BH) and the central stellar velocity dispersion sigma in nearby elliptical galaxies affords a novel way to determine M(BH) in active galaxies. We report on measurements of sigma from optical spectra of 7 BL Lac host galaxies. The range of sigma (160 - 290 km/s) corresponds to estimated M(BH) of 5 x 10^7 - 9 x 10^8 Mo. The average ratio of M(BH) to the host galaxy mass is 1.4 x 10^-3, consistent with that estimated in other active and inactive galaxies...

  20. Theoretical re-evaluations of the black hole mass-bulge mass relation - I. Effect of seed black hole mass

    Science.gov (United States)

    Shirakata, Hikari; Kawaguchi, Toshihiro; Okamoto, Takashi; Makiya, Ryu; Ishiyama, Tomoaki; Matsuoka, Yoshiki; Nagashima, Masahiro; Enoki, Motohiro; Oogi, Taira; Kobayashi, Masakazu A. R.

    2016-10-01

    We explore the effect of varying the mass of a seed black hole on the resulting black hole mass-bulge mass relation at z ˜ 0, using a semi-analytic model of galaxy formation combined with large cosmological N-body simulations. We constrain our model by requiring that the observed properties of galaxies at z ˜ 0 are reproduced. In keeping with previous semi-analytic models, we place a seed black hole immediately after a galaxy forms. When the mass of the seed is set at 105 M⊙, we find that the model results become inconsistent with recent observational results of the black hole mass-bulge mass relation for dwarf galaxies. In particular, the model predicts that bulges with ˜109 M⊙ harbour larger black holes than observed. On the other hand, when we employ seed black holes of 103 M⊙ or select their mass randomly within a 103-5 M⊙ range, the resulting relation is consistent with observation estimates, including the observed dispersion. We find that, to obtain stronger constraints on the mass of seed black holes, observations of less massive bulges at z ˜ 0 are a more powerful comparison than the relations at higher redshifts.

  1. Mechanism for the suppression of intermediate-mass black holes

    Science.gov (United States)

    Dokuchaev, V. I.; Eroshenko, Yu. N.; Rubin, S. G.; Samarchenko, D. A.

    2010-11-01

    A model for the formation of supermassive primordial black holes in galactic nuclei with the simultaneous suppression of the formation of intermediate-mass black holes is presented. A bimodal mass function for black holes formed through phase transitions in a model with a “Mexican hat” potential has been found. The classical motion of the phase of a complex scalar field during inflation has been taken into account. Possible observational manifestations of primordial black holes in galaxies and constraints on their number are discussed.

  2. Mechanism for the Suppression of Intermediate-Mass Black Holes

    CERN Document Server

    Dokuchaev, V I; Rubin, S G; Samarchenko, D A; 10.1134/S1063773710110022

    2010-01-01

    A model for the formation of supermassive primordial black holes in galactic nuclei with the simultaneous suppression of the formation of intermediate-mass black holes is presented. A bimodal mass function for black holes formed through phase transitions in a model with a "Mexican hat" potential has been found. The classical motion of the phase of a complex scalar field during inflation has been taken into account. Possible observational manifestations of primordial black holes in galaxies and constraints on their number are discussed.

  3. Precise Black Hole Masses From Megamaser Disks: Black Hole-Bulge Relations at Low Mass

    OpenAIRE

    Greene, J. E.; Peng, C. Y.; Kim, M.; Kuo, C. Y.; Braatz, J. A.; Impellizzeri, C. M. V.; Condon, J. J.; Lo, K. Y.; Henkel, C; Reid, M J

    2010-01-01

    The black hole (BH)-bulge correlations have greatly influenced the last decade of effort to understand galaxy evolution. Current knowledge of these correlations is limited predominantly to high BH masses (M_BH> 10^8 M_sun) that can be measured using direct stellar, gas, and maser kinematics. These objects, however, do not represent the demographics of more typical L< L* galaxies. This study transcends prior limitations to probe BHs that are an order of magnitude lower in mass, using BH mass m...

  4. Observing stellar mass and supermassive black holes

    Science.gov (United States)

    Cherepashchuk, A. M.

    2016-07-01

    During the last 50 years, great progress has been made in observing stellar-mass black holes (BHs) in binary systems and supermassive BHs in galactic nuclei. In 1964, Zeldovich and Salpeter showed that in the case of nonspherical accretion of matter onto a BH, huge energy releases occur. The theory of disk accretion of matter onto BHs was developed in 1972-1973 by Shakura and Sunyaev, Pringle and Rees, and Novikov and Thorne. Up to now, 100 years after the creation of Albert Einstein's General Theory of Relativity, which predicts the existence of BHs, the masses of tens of stellar-mass BHs ( M_BH=(4-35) M_⊙) and many hundreds of supermassive BHs ( M_BH=(10^6-1010) M_⊙) have been determined. A new field of astrophysics, so-called BH demography, is developing. The recent discovery of gravitational waves from BH mergers in binary systems opens a new era in BH studies.

  5. Black-hole bombs and photon-mass bounds.

    Science.gov (United States)

    Pani, Paolo; Cardoso, Vitor; Gualtieri, Leonardo; Berti, Emanuele; Ishibashi, Akihiro

    2012-09-28

    Generic extensions of the standard model predict the existence of ultralight bosonic degrees of freedom. Several ongoing experiments are aimed at detecting these particles or constraining their mass range. Here we show that massive vector fields around rotating black holes can give rise to a strong superradiant instability, which extracts angular momentum from the hole. The observation of supermassive spinning black holes imposes limits on this mechanism. We show that current supermassive black-hole spin estimates provide the tightest upper limits on the mass of the photon (m(v) is black holes could further lower this bound to m(v) black holes in the slow-rotation regime, that we developed up to second order in rotation, and that can be extended to other spacetime metrics and other theories.

  6. Initial mass function of intermediate mass black hole seeds

    CERN Document Server

    Ferrara, A; Yue, B; Schleicher, D R G

    2014-01-01

    We study the Initial Mass Function (IMF) and host halo properties of Intermediate Mass Black Holes (IMBH, 10^{4-6} Msun) formed inside metal-free, UV illuminated atomic cooling haloes (virial temperature T_vir > 10^4 K) either via the direct collapse of the gas or via an intermediate Super Massive Star (SMS) stage. We achieve this goal in three steps: (a) we derive the gas accretion rate for a proto-SMS to undergo General Relativity instability and produce a direct collapse black hole (DCBH) or to enter the ZAMS and later collapse into a IMBH; (b) we use merger-tree simulations to select atomic cooling halos in which either a DCBH or SMS can form and grow, accounting for metal enrichment and major mergers that halt the growth of the proto-SMS by gas fragmentation. We derive the properties of the host halos and the mass distribution of black holes at this stage, and dub it the "Birth Mass Function"; (c) we follow the further growth of the DCBH due to accretion of leftover gas in the parent halo and compute the...

  7. From X-ray binaries to quasars black holes on all mass scales black holes on all mass scales

    CERN Document Server

    Ho, L C; Maccarone, T J

    2005-01-01

    This volume brings together contributions from many of the world's leading authorities on black hole accretion. The papers within represent part of a new movement to make use of the relative advantages of studying stellar mass and supermassive black holes and to bring together the knowledge gained from the two approaches. The topics discussed here run the gamut of the state of the art in black hole observational and theoretical work-variability, spectroscopy, disk-jet connections, and multi-wavelength campaigns on black holes are all covered. Reprinted from ASTROPHYSICS AND SPACE SCIENCE, 300:1-3 (2005)

  8. The mass function of nearby black hole candidates

    CERN Document Server

    Caramete, Laurentiu I

    2009-01-01

    The mass function of super-massive black holes in our cosmic neighborhood is required to understand the statistics of activity, specifically the production of ultra high energy particles. We determine a mass function of black hole candidates from the entire sky outside the Galactic plane. Using the 2MASS catalogue as a starting point, and the well established correlation between black hole mass and the old bulge population of stars, we derive a list of nearby black hole candidates within the redshift range z 10^7 M_sol has 5,634 entries. Here we use this catalogue to derive the mass function. We correct for volume, so that this mass function is a volume limited distribution to redshift 0.025. The mass function of nearby black hole candidates is a straight simple power-law, extending down into the mass range, where nuclear star clusters may replace the super-massive black holes. The slope of this mass function can be explained in a simple merger picture. Integrating this mass function over the redshift range,...

  9. Prospects for Measuring Supermassive Black Hole Masses with TMT

    Science.gov (United States)

    Do, Tuan; Wright, Shelley A.; Barth, Aaron J.; Barton, Elizabeth J.; Simard, Luc; Larkin, James E.; Moore, Anna M.; Wang, Lianqi; Ellerbroek, Brent

    2014-07-01

    The next generation of giant-segmented mirror telescopes will enable us to observe galactic nuclei at much higher angular resolution and sensitivity than ever before. These capabilities will introduce a revolutionary shift in our understanding of the origin and evolution of supermassive black holes by enabling more precise black hole mass measurements in a mass range that is unreachable today. We present simulations and predictions of the observations of nuclei that will be made with the Thirty Meter Telescope and the adaptive optics assisted integral- field spectrograph IRIS, which is capable of diffraction-limited spectroscopy from Z band (0.9 μm) to K band (2.2 μm). These simulations, for the first time, use realistic values for the sky, telescope, adaptive optics system, and instrument to determine the expected signal-to-noise ratio of a range of possible targets spanning intermediate mass black holes of ˜10^4 M⊙ to the most massive black holes known today of >10^10 M⊙. I will present simulations across a spectrum of black hole masses and galaxy types to show the ability of IRIS and TMT to quantitatively explore the demographics of black holes in the universe. I will discuss how these observations will enable our study of the origin of the MBH - galaxy velocity dispersion and MBH - galaxy luminosity relationships, and the evolution of black holes through cosmic time.

  10. Vacum Black Hole Mass Formula Is a Vanishing Noether Charge

    Institute of Scientific and Technical Information of China (English)

    WUXiao-Ning; HUANGChao-Guang; 等

    2002-01-01

    The Noether current and its variation relation with respect to diffeomorphism invariance of gravitational theories have been derived from the horizontal variation and vertical-horizontal bi-variation of the Lagrangian,respectively.For Einstein's GR in the stationary,axisymmetric black holes,the mass formula in vacuum can be derived from this Noether current although it definitely vanishes.This indicates that the mass formula of black holes is a vanishing Noether charge in this case.The first law of black hole thermodynamics can also be derived from the variation relation of this vanishing Noether current.

  11. ADM mass of the quantum-corrected Schwarzchild black hole

    CERN Document Server

    Buric, M; Buric, Maja; Radovanovic, Voja

    2000-01-01

    We study the hamiltonian and constraints of spherically symmetric dilaton gravity model. We find the ADM mass of the solution representing the Schwarzchild black hole in thermal equilibrium with the Hawking radiation.

  12. On the black hole mass decomposition in nonlinear electrodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Jonas P. [ICRANet, Piazza della Repubblica 10, I-65122 Pescara (Italy); Dip. di Fisica and ICRA, Sapienza Università di Roma, P.le Aldo Moro 5, I-00185 Rome (Italy); Université de Nice Sophia Antipolis, 28 Av. de Valrose, 06103 Nice Cedex 2 (France); Mosquera Cuesta, Herman J. [ICRANet, Piazza della Repubblica 10, I-65122 Pescara (Italy); Instituto Federal de Educação, Ciência e Tecnologia do Ceará, Avenida Treze de Maio, 2081, Benfica, Fortaleza/CE, CEP 60040-531 (Brazil); ICRANet-Rio, Centro Brasileiro de Pesquisas Físicas, Rua Dr. Xavier Sigaud 150, Rio de Janeiro, RJ, 22290-180 (Brazil); Rueda, Jorge A. [ICRANet, Piazza della Repubblica 10, I-65122 Pescara (Italy); Dip. di Fisica and ICRA, Sapienza Università di Roma, P.le Aldo Moro 5, I-00185 Rome (Italy); ICRANet-Rio, Centro Brasileiro de Pesquisas Físicas, Rua Dr. Xavier Sigaud 150, Rio de Janeiro, RJ, 22290-180 (Brazil); Ruffini, R. [ICRANet, Piazza della Repubblica 10, I-65122 Pescara (Italy); Dip. di Fisica and ICRA, Sapienza Università di Roma, P.le Aldo Moro 5, I-00185 Rome (Italy); ICRANet-Rio, Centro Brasileiro de Pesquisas Físicas, Rua Dr. Xavier Sigaud 150, Rio de Janeiro, RJ, 22290-180 (Brazil); Université de Nice Sophia Antipolis, 28 Av. de Valrose, 06103 Nice Cedex 2 (France)

    2014-06-27

    In the weak field limit of nonlinear Lagrangians for electrodynamics, i.e. theories in which the electric fields are much smaller than the scale (threshold) fields introduced by the nonlinearities, a generalization of the Christodoulou–Ruffini mass formula for charged black holes is presented. It proves that the black hole outer horizon never decreases. It is also demonstrated that reversible transformations are, indeed, fully equivalent to constant horizon solutions for nonlinear theories encompassing asymptotically flat black hole solutions. This result is used to decompose, in an analytical and alternative way, the total mass-energy of nonlinear charged black holes, circumventing the difficulties faced to obtain it via the standard differential approach. It is also proven that the known first law of black hole thermodynamics is the direct consequence of the mass decomposition for general black hole transformations. From all the above we finally show a most important corollary: for relevant astrophysical scenarios nonlinear electrodynamics decreases the extractable energy from a black hole with respect to the Einstein–Maxwell theory. Physical interpretations for these results are also discussed.

  13. Estimates of AGN Black Hole Mass and Minimum Variability Timescale

    Institute of Scientific and Technical Information of China (English)

    Guang-Zhong Xie; Luo-En Chen; Huai-Zhen Li; Li-Sheng Mao; Hong Dai; Zhao-Hua Xie; Li Ma; Shu-Bai Zhou

    2005-01-01

    Black hole mass is one of the fundamental physical parameters of active galactic nuclei (AGNs), for which many methods of estimation have been proposed.One set of methods assumes that the broad-line region (BLR) is gravitationally bound by the central black hole potential, so the black hole mass can be estimated from the orbital radius and the Doppler velocity. Another set of methods assumes the observed variability timescale is determined by the orbital timescale near the innermost stable orbit around the Schwarzschild black hole or the Kerr black hole,or by the characteristic timescale of the accretion disk. We collect a sample of 21AGNs, for which the minimum variability timescales have been obtained and their black hole masses (Mσ) have been well estimated from the stellar velocity dispersion or the BLR size-luminosity relation. Using the minimum variability timescales we estimated the black hole masses for 21 objects by the three different methods,the results are denoted by Ms, Mk and Md, respectively. We compared each of them with Mσ individually and found that: (1) using the minimum variability timescale with the Kerr black hole theory leads to small differences between Mσand Mk, none exceeding one order of magnitude, and the mean difference between them is about 0.53 dex; (2) using the minimum variability timescale with the Schwarzschild black hole theory leads to somewhat larger difference between Mσ and Ms: larger than one order of magnitude for 6 of the 21 sources, and the mean difference is 0.74 dex; (3) using the minimum variability timescale with the accretion disk theory leads to much larger differences between Mσ and Md, for 13of the 21 sources the differences are larger than two orders of magnitude; and the mean difference is as high as about 2.01 dex.

  14. The mass formula for an exotic BTZ black hole

    Science.gov (United States)

    Zhang, Baocheng

    2016-04-01

    An exotic Bañados-Teitelboim-Zanelli (BTZ) black hole has an angular momentum larger than its mass in three dimension (3D), which suggests the possibility that cosmic censorship could be violated if angular momentum is extracted by the Penrose process. In this paper, we propose a mass formula for the exotic BTZ black hole and show no violation of weak cosmic censorship in the gedanken process above by understanding properly its mass formula. Unlike the other black holes, the total energy of the exotic BTZ black hole is represented by the angular momentum instead of the mass, which supports a basic point of view that the same geometry should be determined by the same energy in 3D general relativity whose equation of motion can be given either by normal 3D Einstein gravity or by exotic 3D Einstein gravity. However, only the mass of the exotic black hole is related to the thermodynamics and other forms of energy are "dumb", which is consistent with the earlier thermodynamic analysis about exotic black holes.

  15. The mass formula for an exotic BTZ black hole

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Baocheng, E-mail: zhangbc.zhang@yahoo.com

    2016-04-15

    An exotic Bañados–Teitelboim–Zanelli (BTZ) black hole has an angular momentum larger than its mass in three dimension (3D), which suggests the possibility that cosmic censorship could be violated if angular momentum is extracted by the Penrose process. In this paper, we propose a mass formula for the exotic BTZ black hole and show no violation of weak cosmic censorship in the gedanken process above by understanding properly its mass formula. Unlike the other black holes, the total energy of the exotic BTZ black hole is represented by the angular momentum instead of the mass, which supports a basic point of view that the same geometry should be determined by the same energy in 3D general relativity whose equation of motion can be given either by normal 3D Einstein gravity or by exotic 3D Einstein gravity. However, only the mass of the exotic black hole is related to the thermodynamics and other forms of energy are “dumb”, which is consistent with the earlier thermodynamic analysis about exotic black holes.

  16. The mass formula for an exotic BTZ black hole

    CERN Document Server

    Zhang, Baocheng

    2016-01-01

    An exotic Banados-Teitelboim-Zanelli (BTZ) black hole has an angular momentum larger than its mass in three dimension (3D), which suggests the possibility that cosmic censorship could be violated if angular momentum is extracted by the Penrose process. In this paper, we propose a mass formula for the exotic BTZ black hole and show no violation of weak cosmic censorship in the gedanken process above by understanding properly its mass formula. Unlike the other black holes, the total energy of the exotic BTZ black hole is represented by the angular momentum instead of the mass, which supports a basic point of view that the same geometry should be determined by the same energy in 3D general relativity whose equation of motion can be given either by normal 3D Einstein gravity or by exotic 3D Einstein gravity. However, only the mass of the exotic black hole is related to the thermodynamics and other forms of energy are "dumb", which is consistent with the earlier thermodynamic analysis about exotic black holes.

  17. Feedback Limits to Maximum Seed Masses of Black Holes

    Science.gov (United States)

    Pacucci, Fabio; Natarajan, Priyamvada; Ferrara, Andrea

    2017-02-01

    The most massive black holes observed in the universe weigh up to ∼1010 M ⊙, nearly independent of redshift. Reaching these final masses likely required copious accretion and several major mergers. Employing a dynamical approach that rests on the role played by a new, relevant physical scale—the transition radius—we provide a theoretical calculation of the maximum mass achievable by a black hole seed that forms in an isolated halo, one that scarcely merged. Incorporating effects at the transition radius and their impact on the evolution of accretion in isolated halos, we are able to obtain new limits for permitted growth. We find that large black hole seeds (M • ≳ 104 M ⊙) hosted in small isolated halos (M h ≲ 109 M ⊙) accreting with relatively small radiative efficiencies (ɛ ≲ 0.1) grow optimally in these circumstances. Moreover, we show that the standard M •–σ relation observed at z ∼ 0 cannot be established in isolated halos at high-z, but requires the occurrence of mergers. Since the average limiting mass of black holes formed at z ≳ 10 is in the range 104–6 M ⊙, we expect to observe them in local galaxies as intermediate-mass black holes, when hosted in the rare halos that experienced only minor or no merging events. Such ancient black holes, formed in isolation with subsequent scant growth, could survive, almost unchanged, until present.

  18. Precise Black Hole Masses from Megamaser Disks: Black Hole-Bulge Relations at Low Mass

    Science.gov (United States)

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

    2010-09-01

    The black hole (BH)-bulge correlations have greatly influenced the last decade of efforts to understand galaxy evolution. Current knowledge of these correlations is limited predominantly to high BH masses (M BHgsim108 M sun) that can be measured using direct stellar, gas, and maser kinematics. These objects, however, do not represent the demographics of more typical L BH mass measurements derived from the dynamics of H2O megamasers in circumnuclear disks. The masers trace the Keplerian rotation of circumnuclear molecular disks starting at radii of a few tenths of a pc from the central BH. Modeling of the rotation curves, presented by Kuo et al., yields BH masses with exquisite precision. We present stellar velocity dispersion measurements for a sample of nine megamaser disk galaxies based on long-slit observations using the B&C spectrograph on the Dupont telescope and the Dual Imaging Spectrograph on the 3.5 m telescope at Apache Point. We also perform bulge-to-disk decomposition of a subset of five of these galaxies with Sloan Digital Sky Survey imaging. The maser galaxies as a group fall below the M BH-σ* relation defined by elliptical galaxies. We show, now with very precise BH mass measurements, that the low-scatter power-law relation between M BH and σ* seen in elliptical galaxies is not universal. The elliptical galaxy M BH-σ* relation cannot be used to derive the BH mass function at low mass or the zero point for active BH masses. The processes (perhaps BH self-regulation or minor merging) that operate at higher mass have not effectively established an M BH-σ* relation in this low-mass regime.

  19. Precise Black Hole Masses From Megamaser Disks: Black Hole-Bulge Relations at Low Mass

    CERN Document Server

    Greene, J E; Kim, M; Kuo, C Y; Braatz, J A; Impellizzeri, C M V; Condon, J J; Lo, K Y; Henkel, C; Reid, M J

    2010-01-01

    The black hole (BH)-bulge correlations have greatly influenced the last decade of effort to understand galaxy evolution. Current knowledge of these correlations is limited predominantly to high BH masses (M_BH> 10^8 M_sun) that can be measured using direct stellar, gas, and maser kinematics. These objects, however, do not represent the demographics of more typical L< L* galaxies. This study transcends prior limitations to probe BHs that are an order of magnitude lower in mass, using BH mass measurements derived from the dynamics of H_2O megamasers in circumnuclear disks. The masers trace the Keplerian rotation of circumnuclear molecular disks starting at radii of a few tenths of a pc from the central BH. Modeling of the rotation curves, presented by Kuo et al. (2010), yields BH masses with exquisite precision. We present stellar velocity dispersion measurements for a sample of nine megamaser disk galaxies based on long-slit observations using the B&C spectrograph on the Dupont telescope and the DIS spe...

  20. On Estimating the Total Number of Intermediate Mass Black Holes

    Science.gov (United States)

    Caputo, Daniel P.; de Vries, Nathan; Patruno, Alessandro; Portegies Zwart, Simon

    2017-01-01

    Black holes have been detected with masses less than 102 and greater than 105 M⊙, but black holes with masses in the intermediate range are conspicuously absent. However, recent estimates of the mass of HLX-1, currently the strongest intermediate mass black hole (IMBH) candidate, suggest an approximate mass of 104 M⊙, and recent estimates of the mass of M82 X-1 suggest a mass of 4 × 102, placing them within the missing black hole range. This raises the question of whether these are unique objects or if many more of these objects should be expected. We estimate the number of HLX-1 like IMBHs expected within the distance of 100 Mpc to be within an order of ≈106, or ≈102 IMBHs within a galaxy, and about two orders of magnitude more when considering less massive IMBHs using M82 X-1 as a prototype. In the process of estimating this value we determine the form of the mass function within the sphere of influence of a newly formed IMBH to be a power law with a slope of -1.83. Furthermore, we find we are only able to fit both the period and luminosity of HLX-1 with a stellar companion with a mass between ≈10 - 11 M⊙, a result which is fairly robust to the mass of the IMBH between 103 and 105 M⊙.

  1. Black holes in binary stars

    NARCIS (Netherlands)

    Wijers, R.A.M.J.

    1996-01-01

    Introduction Distinguishing neutron stars and black holes Optical companions and dynamical masses X-ray signatures of the nature of a compact object Structure and evolution of black-hole binaries High-mass black-hole binaries Low-mass black-hole binaries Low-mass black holes Formation of black holes

  2. Inclinations and black hole masses of Seyfert 1 galaxies

    CERN Document Server

    Wu, X B; Wu, Xue-Bing

    2001-01-01

    A tight correlation of black hole mass and central velocity dispersion has been found recently for both active and quiescent galaxies. By applying this correlation, we develop a simple method to derive the inclination angles for a sample of 11 Seyfert 1 galaxies that have both measured central velocity dispersions and black hole masses estimated by reverberation mapping. These angles, with a mean value of 36 degree that agrees well with the result obtained by fitting the iron K$\\alpha$ lines of Seyfert 1s observed with ASCA, provide further support to the orientation-dependent unification scheme of AGN. A positive correlation of the inclinations with observed FWHMs of H$\\beta$ line and a possible anti-correlation with the nuclear radio-loudness have been found. We conclude that more accurate knowledge on inclinations and broad line region dynamics is needed to improve the black hole mass determination of AGN with the reverberation mapping technique.

  3. Cosmological Evolution of Supermassive Black Holes: Mass Functions and Spins

    CERN Document Server

    Li, Yan-Rong; Ho, Luis C

    2012-01-01

    We derive the mass function of supermassive black holes (SMBHs) over the redshift range 0mass functions of field galaxies. Applying this mass function, combined with the bolometric luminosity function of active galactic nuclei (AGNs), into the the continuity equation of SMBH number density, we explicitly obtain the mass-dependent cosmological evolution of the radiative efficiency for accretion. We suggest that the accretion history of SMBHs and their spins evolve in two distinct regimes: an early phase of prolonged accretion, plausibly driven by major mergers, during which the black hole spins up, then switching to a period of random, episodic accretion, governed by minor mergers and internal secular processes, during which the hole spins down. The transition epoch depends on mass, mirroring other evidence for "cosmic downsizing" in the AGN population.

  4. Towards Precision Supermassive Black Hole Masses using Megamaser Disks

    CERN Document Server

    Bosch, Remco C E van den; Braatz, James A; Constantin, Anca; Kuo, Cheng-Yu

    2016-01-01

    Megamaser disks provide the most precise and accurate extragalactic supermassive black hole masses. Here we describe a search for megamasers in nearby galaxies using the Green Bank Telescope (GBT). We focus on galaxies where we believe that we can resolve the gravitational sphere of influence of the black hole and derive a stellar or gas dynamical measurement with optical or NIR observations. Since there are only a handful of super massive black holes (SMBH) that have direct black hole mass measurements from more than one method, even a single galaxy with a megamaser disk and a stellar dynamical black hole mass would provide necessary checks on the stellar dynamical methods. We targeted 87 objects from the Hobby-Eberly Telescope Massive Galaxy Survey, and detected no new maser disks. Most of the targeted objects are elliptical galaxies with typical stellar velocity dispersions of 250 km/s and distances within 130 Mpc. We discuss the implications of our non-detections, whether they imply a threshold X-ray lumi...

  5. Gravitational Radiation of Binaries Coalescence into Intermediate Mass Black Holes

    Institute of Scientific and Technical Information of China (English)

    李瑾; 仲元红; 潘宇

    2012-01-01

    This paper discusses the gravitation waveforms of binaries coalescence into intermediate mass black holes (about 30 times of the solar mass). We focus on the non-spinning intermediate mass black hole located less than 100 Mpc from earth. By comparing two simulation waveforms (effective one body numerical relativity waveform (EOBNR), phenomenological waveform), we discuss the relationship between the effective distance and frequency; and through analyzing large amounts of data in event, we find that the phenomenological waveform is much smoother than EOBNR waveform, and has higher accuracy at the same effective distance.

  6. Dynamical mass ejection from black hole-neutron star binaries

    CERN Document Server

    Kyutoku, Koutarou; Okawa, Hirotada; Shibata, Masaru; Taniguchi, Keisuke

    2015-01-01

    We investigate properties of material ejected dynamically in the merger of black hole-neutron star binaries by numerical-relativity simulations. We systematically study dependence of ejecta properties on the mass ratio of the binary, spin of the black hole, and equation of state of the neutron-star matter. Dynamical mass ejection is driven primarily by tidal torque, and the ejecta is much more anisotropic than that from binary neutron star mergers. In particular, the dynamical ejecta is concentrated around the orbital plane with a half opening angle of 10deg--20deg and often sweeps only a half of the plane. The ejecta mass can be as large as ~0.1M_sun, and the velocity is subrelativistic with ~0.2--0.3c for typical cases. The ratio of the ejecta mass to the bound mass (disk and fallback components) becomes high and the ejecta velocity is large when the binary mass ratio is large, i.e., the black hole is massive. The remnant black hole-disk system receives a kick velocity of O(100)km/s due to the ejecta linear...

  7. Tidal disruption of white dwarfs by intermediate mass black holes

    Directory of Open Access Journals (Sweden)

    Bode T.

    2012-12-01

    Full Text Available Modeling ultra-close encounters between a white dwarf and a spinning, intermediate mass black hole requires a full general relativistic treatment of gravity. This paper summarizes results from such a study. Our results show that the disruption process and prompt accretion of the debris strongly depend on the magnitude and orientation of the black hole spin. On the other hand, the late-time accretion onto the black hole follows the same decay, Ṁ ∝  t−5/3, estimated from Newtonian gravity disruption studies. The spectrum of the fallback material peaks in the soft X-rays and sustains Eddington luminosity for 1–3 yrs after the disruption. The orientation of the black hole spin has also a profound effect on how the outflowing debris obscures the central region. The disruption produces a burst of gravitational radiation with characteristic frequencies of ∼3.2 Hz and strain amplitudes of ∼10−18 for galactic intermediate mass black holes.

  8. Determining Central Black Hole Masses in Distant Active Galaxies

    DEFF Research Database (Denmark)

    Vestergaard, Marianne

    2002-01-01

    An empirical relationship, of particular interest for studies of high redshift active galactic nuclei (AGNs) and quasars, between the masses of their central black-holes and rest-frame ultraviolet (UV) parameters measured in single-epoch AGN spectra is presented. This relationship is calibrated...... black-hole demographics at high redshift as well as to statistically study the fundamental properties of AGNs. The broad line region size - luminosity relationship is key to the calibrations presented here. The fact that its intrinsic scatter is also the main source of uncertainty in the calibrations...

  9. Super-massive black hole mass scaling relations

    CERN Document Server

    Graham, Alister W; Schombert, James

    2014-01-01

    Using black hole masses which span 10^5 to 10^(10) solar masses, the distribution of galaxies in the (host spheroid stellar mass)-(black hole mass) diagram is shown to be strongly bent. While the core-Sersic galaxies follow a near-linear relation, having a mean M_(bh)/M_(sph) mass ratio of ~0.5%, the Sersic galaxies follow a near-quadratic relation: M_bh~M_sph^(2.22+\\-0.58). This is not due to offset pseudobulges, but is instead an expected result arising from the long-known bend in the M_(sph)-sigma relation and the log-linear M_(bh)-sigma relation.

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

    Science.gov (United States)

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

    2012-05-01

    We present the results of a weakly modeled burst search for gravitational waves from mergers of nonspinning intermediate mass black holes in the total mass range 100-450M⊙ 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 intermediate mass black holes mergers as a function of the component masses. In the most efficiently detected bin centered on 88+88M⊙, for nonspinning sources, the rate density upper limit is 0.13 per Mpc3 per Myr at the 90% confidence level.

  11. The large-mass limit of cloudy black holes

    CERN Document Server

    Hod, Shahar

    2016-01-01

    The interplay between black holes and fundamental fields has attracted much attention over the years from both physicists and mathematicians. In this paper we study {\\it analytically} a physical system which is composed of massive scalar fields linearly coupled to a rapidly-rotating Kerr black hole. Using simple arguments, we first show that the coupled black-hole-scalar-field system may possess stationary bound-state resonances (stationary scalar `clouds') in the bounded regime $1<\\mu/m\\Omega_{\\text{H}}<\\sqrt{2}$, where $\\mu$ and $m$ are respectively the mass and azimuthal harmonic index of the field, and $\\Omega_{\\text{H}}$ is the angular velocity of the black-hole horizon. We then show explicitly that these two bounds on the dimensionless ratio $\\mu/m\\Omega_{\\text{H}}$ can be saturated in the asymptotic $m\\to\\infty$ limit. In particular, we derive a remarkably simple analytical formula for the resonance mass spectrum of the stationary bound-state scalar clouds in the regime $M\\mu\\gg1$ of large field ...

  12. Black Hole Mass Estimates of Radio Selected Quasars

    OpenAIRE

    Oshlack, Alicia; Webster, Rachel; Whiting, Matthew

    2002-01-01

    The black hole (BH) mass in the centre of AGN has been estimated for a sample of radio-selected flat-spectrum quasars to investigate the relationship between BH mass and radio properties of quasars. We have used the virial assumption with measurements of the H$\\beta$ FWHM and luminosity to estimate the central BH mass. In contrast to previous studies we find no correlation between BH mass and radio power in these AGN. We find a range in BH mass similar to that seen in radio-quiet quasars from...

  13. Dynamical black hole masses of BL Lac objects from the Sloan Digital Sky Survey

    NARCIS (Netherlands)

    Plotkin, R. M.; Markoff, S.; Trager, S. C.; Anderson, S. F.

    2011-01-01

    We measure black hole masses for 71 BL Lac objects from the Sloan Digital Sky Survey with redshifts out to z˜ 0.4. We perform spectral decompositions of their nuclei from their host galaxies and measure their stellar velocity dispersions. Black hole masses are then derived from the black hole mass -

  14. Dynamical black hole masses of BL Lac objects from the Sloan Digital Sky Survey

    NARCIS (Netherlands)

    Plotkin, R.M.; Markoff, S.; Trager, S.C.; Anderson, S.F.

    2011-01-01

    We measure black hole masses for 71 BL Lac objects from the Sloan Digital Sky Survey with redshifts out to z∼ 0.4. We perform spectral decompositions of their nuclei from their host galaxies and measure their stellar velocity dispersions. Black hole masses are then derived from the black hole mass -

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

    CERN Document Server

    Arun, K G; Sathyaprakash, B S; Sinha, Siddhartha

    2007-01-01

    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...

  16. Mass loss from advective accretion disc around rotating black holes

    CERN Document Server

    Aktar, Ramiz; Nandi, Anuj

    2015-01-01

    We examine the properties of the outflowing matter from an advective accretion disc around a spinning black hole. During accretion, rotating matter experiences centrifugal pressure supported shock transition that effectively produces a virtual barrier around the black hole in the form of post-shock corona (hereafter, PSC). Due to shock compression, PSC becomes hot and dense that eventually deflects a part of the inflowing matter as bipolar outflows because of the presence of extra thermal gradient force. In our approach, we study the outflow properties in terms of the inflow parameters, namely specific energy (${\\mathcal E}$) and specific angular momentum ($\\lambda$) considering the realistic outflow geometry around the rotating black holes. We find that spin of the black hole ($a_k$) plays an important role in deciding the outflow rate $R_{\\dot m}$ (ratio of mass flux of outflow and inflow), in particular, $R_{\\dot m}$ is directly correlated with $a_k$ for the same set of inflow parameters. It is found that ...

  17. AGN Black Hole Masses from Reverberation Mapping

    Science.gov (United States)

    Peterson, B. M.

    2004-01-01

    Emission-line variability data on bright AGNs indicates that the central objects in these sources have masses in the million to few-hundred million solar mass range. The time-delayed response of the emission lines to continuum variations can be used to infer the size of the line-emitting region via light travel-time arguments. By combining these sizes with the Doppler widths of the variable part of the emission lines, a virial mass estimate can be obtained. For three especially well-studied sources, NGC 5548, NGC 7469, and 3C 390.3, data on multiple emission lines can be used to test the virial hypothesis. In each of these cases, the response time of the various emission lines is anticorrelated with the line width, with the dependence as expected for gravitationally bound motion of the line-emitting clouds, i.e., that the square of the Doppler line width is inversely proportional to the emission-line time delay. Virial masses based on the Balmer lines have now been measured for about three dozen AGNs. Systematic effects currently limit the accuracy of these masses to a factor of several, but characteristics of the radius-luminosity and mass-luminosity relationships for AGNs are beginning to emerge.

  18. Intermediate Mass Black Holes: Their Motion and Associated Energetics

    Directory of Open Access Journals (Sweden)

    C. Sivaram

    2014-01-01

    Full Text Available There is a lot of current astrophysical evidence and interest in intermediate mass black holes (IMBH, ranging from a few hundred to several thousand solar masses. The active galaxy M82 and the globular cluster G1 in M31, for example, are known to host such objects. Here, we discuss several aspects of IMBH such as their expected luminosity, spectral nature of radiation, and associated jets. We also discuss possible scenarios for their formation including the effects of dynamical friction, and gravitational radiation. We also consider their formation in the early universe and also discuss the possibility of supermassive black holes forming from mergers of several IMBH and compare the relevant time scales involved with other scenarios.

  19. The Black Hole Mass Function from Gravitational Wave Measurements

    CERN Document Server

    Kovetz, Ely D; Breysse, Patrick C; Kamionkowski, Marc

    2016-01-01

    We examine how future gravitational-wave measurements from merging black holes (BHs) can be used to infer the shape of the black-hole mass function, with important implications for the study of star formation and evolution and the properties of binary BHs. We model the mass function as a power law, inherited from the stellar initial mass function, and introduce lower and upper mass cutoff parameterizations in order to probe the minimum and maximum BH masses allowed by stellar evolution, respectively. We initially focus on the heavier BH in each binary, to minimize model dependence. Taking into account the experimental noise, the mass measurement errors and the uncertainty in the redshift-dependence of the merger rate, we show that the mass function parameters, as well as the total rate of merger events, can be measured to <10% accuracy within a few years of advanced LIGO observations at its design sensitivity. This can be used to address important open questions such as the upper limit on the stellar mass ...

  20. Natal kicks of stellar mass black holes by asymmetric mass ejection in fallback supernovae

    Science.gov (United States)

    Janka, Hans-Thomas

    2013-09-01

    Integrating trajectories of low-mass X-ray binaries containing black holes within the Galactic potential, Repetto, Davies & Sigurdsson recently showed that the large distances of some systems above the Galactic plane can only be explained if black holes receive appreciable natal kicks. Surprisingly, they found that the distribution of black hole kick velocities (rather than that of the momenta) should be similar to that of neutron stars. Here I argue that this result can be understood if neutron star and black hole kicks are a consequence of large-scale asymmetries created in the supernova ejecta by the explosion mechanism. The corresponding anisotropic gravitational attraction of the asymmetrically expelled matter does not only accelerate new-born neutron stars by the `gravitational tug-boat mechanism', but can also lead to delayed black hole formation by asymmetric fallback of the slowest parts of the initial ejecta on to the transiently existing neutron star, in course of which the momentum of the black hole can grow with the fallback mass. Black hole kick velocities will therefore not be reduced by the ratio of neutron star to black hole mass as would be expected for kicks caused by anisotropic neutrino emission of the nascent neutron star.

  1. Intermediate mass black holes in AGN disks: I. Production & Growth

    CERN Document Server

    McKernan, B; Lyra, W; Perets, H B

    2012-01-01

    Here we propose a mechanism for efficiently growing intermediate mass black holes (IMBH) in disks around supermassive black holes. Stellar mass objects can efficiently agglomerate when facilitated by the gas disk. Stars, compact objects and binaries can migrate, accrete and merge within disks around supermassive black holes. While dynamical heating by cusp stars excites the velocity dispersion of nuclear cluster objects (NCOs) in the disk, gas in the disk damps NCO orbits. If gas damping dominates, NCOs remain in the disk with circularized orbits and large collision cross-sections. IMBH seeds can grow extremely rapidly by collisions with disk NCOs at low relative velocities, allowing for super-Eddington growth rates. Once an IMBH seed has cleared out its feeding zone of disk NCOs, growth of IMBH seeds can become dominated by gas accretion from the AGN disk. However, the IMBH can migrate in the disk and expand its feeding zone, permitting a super-Eddington accretion rate to continue. Growth of IMBH seeds via N...

  2. The Mass of Kerr-Newman Black Holes in an external magnetic field

    CERN Document Server

    Astorino, M; Oliveri, R; Vandevoorde, N

    2016-01-01

    The explicit solution for a Kerr-Newman black hole immersed in an external magnetic field, sometimes called the Melvin-Kerr-Newman black hole, has been derived by Ernst and Wild in 1976. In this paper, we clarify the first law and Smarr formula for black holes in a magnetic field. We then define the unique mass which is integrable and reduces to the Kerr-Newman mass in the absence of magnetic field. This defines the thermodynamic potentials of the black hole. Quite strikingly, the mass coincides with the standard Christodoulou-Ruffini mass of a black hole as a function of the entropy, angular momentum and electric charge.

  3. Black Holes

    Science.gov (United States)

    Luminet, Jean-Pierre

    1992-09-01

    Foreword to the French edition; Foreword to the English edition; Acknowledgements; Part I. Gravitation and Light: 1. First fruits; 2. Relativity; 3. Curved space-time; Part II. Exquisite Corpses: 4. Chronicle of the twilight years; 5. Ashes and diamonds; 6. Supernovae; 7. Pulsars; 8. Gravitation triumphant; Part III. Light Assassinated: 9. The far horizon; 10. Illuminations; 11. A descent into the maelstrom; 12. Map games; 13. The black hole machine; 14. The quantum black hole; Part IV. Light Regained: 15. Primordial black holes; 16. The zoo of X-ray stars; 17. Giant black holes; 18. Gravitational light; 19. The black hole Universe; Appendices; Bibliography; Name index; Subject index.

  4. Mass inflation and chaotic behaviour inside hairy black holes

    CERN Document Server

    Breitenlohner, P; Maison, D; Breitenlohner, Peter; Lavrelashvili, George; Maison, Dieter

    1998-01-01

    We analyze the interior geometry of static, spherically symmetric black holes of the Einstein-Yang-Mills-Higgs theory. Generically the solutions exhibit a behaviour that may be described as ``mass inflation'', although with a remarkable difference between the cases with and without a Higgs field. Without Higgs field the YM field induces a kind of cyclic behaviour leading to repeated cycles of mass inflation - taking the form of violent explosions - interrupted by quiescent periods and subsequent approaches to an almost Cauchy horizon. With the Higgs field no such cycles occur. In addition there are non-generic families with a Schwarzschild resp. Reissner-Nordstr{ø}m type singularity at r=0.

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

    CERN Document Server

    Abadie, J; Abbott, R; Abbott, T D; Abernathy, M; Accadia, T; Acernese, F; Adams, C; Adhikari, R; Affeldt, C; Agathos, M; Agatsuma, K; Ajith, P; Allen, B; Ceron, E Amador; Amariutei, D; Anderson, S B; Anderson, W G; Arai, K; Arain, M A; Araya, M C; Aston, S M; Astone, P; Atkinson, D; Aufmuth, P; Aulbert, C; Aylott, B E; Babak, S; Baker, P; Ballardin, G; Ballmer, S; Baragoya, J C B; Barker, D; Barone, F; Barr, B; Barsotti, L; Barsuglia, M; Barton, M A; Bartos, I; Bassiri, R; Bastarrika, M; Basti, A; Batch, J; Bauchrowitz, J; Bauer, Th S; Bebronne, M; Beck, D; Behnke, B; Bejger, M; Beker, M G; Bell, A S; Belletoile, A; Belopolski, I; Benacquista, M; Berliner, J M; Bertolini, A; Betzwieser, J; Beveridge, N; Beyersdorf, P T; Bilenko, I A; Billingsley, G; Birch, J; Biswas, R; Bitossi, M; Bizouard, M A; Black, E; Blackburn, J K; Blackburn, L; Blair, D; Bland, B; Blom, M; Bock, O; Bodiya, T P; Bogan, C; Bondarescu, R; Bondu, F; Bonelli, L; Bonnand, R; Bork, R; Born, M; Boschi, V; Bose, S; Bosi, L; Bouhou, B; Braccini, S; Bradaschia, C; Brady, P R; Braginsky, V B; Branchesi, M; Brau, J E; Breyer, J; Briant, T; Bridges, D O; Brillet, A; Brinkmann, M; Brisson, V; Britzger, M; Brooks, A F; Brown, D A; Bulik, T; Bulten, H J; Buonanno, A; Burguet-Castell, J; Buskulic, D; Buy, C; Byer, R L; Cadonati, L; Cagnoli, G; Calloni, E; Camp, J B; Campsie, P; Cannizzo, J; Cannon, K; Canuel, B; Cao, J; Capano, C D; Carbognani, F; Carbone, L; Caride, S; Caudill, S; Cavaglia, M; Cavalier, F; Cavalieri, R; Cella, G; Cepeda, C; Cesarini, E; Chaibi, O; Chalermsongsak, T; Charlton, P; Chassande-Mottin, E; Chelkowski, S; Chen, W; Chen, X; Chen, Y; Chincarini, A; Chiummo, A; Cho, H; Chow, J; Christensen, N; Chua, S S Y; Chung, C T Y; Chung, S; Ciani, G; Clark, D E; Clark, J; Clayton, J H; Cleva, F; Coccia, E; Cohadon, P -F; Colacino, C N; Colas, J; Colla, A; Colombini, M; Conte, A; Conte, R; Cook, D; Corbitt, T R; Cordier, M; Cornish, N; Corsi, A; Costa, C A; Coughlin, M; Coulon, J -P; Couvares, P; Coward, D M; Cowart, M; Coyne, D C; Creighton, J D E; Creighton, T D; Cruise, A M; Cumming, A; Cunningham, L; Cuoco, E; Cutler, R M; Dahl, K; Danilishin, S L; Dannenberg, R; D'Antonio, S; Danzmann, K; Dattilo, V; Daudert, B; Daveloza, H; Davier, M; Daw, E J; Day, R; Dayanga, T; De Rosa, R; DeBra, D; Debreczeni, G; Del Pozzo, W; del Prete, M; Dent, T; Dergachev, V; DeRosa, R; DeSalvo, R; Dhurandhar, S; Di Fiore, L; Di Lieto, A; Di Palma, I; Emilio, M Di Paolo; Di Virgilio, A; Diaz, M; Dietz, A; Donovan, F; Dooley, K L; Drago, M; Drever, R W P; Driggers, J C; Du, Z; Dumas, J -C; Eberle, T; Edgar, M; Edwards, M; Effler, A; Ehrens, P; Endroczi, G; Engel, R; Etzel, T; Evans, K; Evans, M; Evans, T; Factourovich, M; Fafone, V; Fairhurst, S; Fan, Y; Farr, B F; Fazi, D; Fehrmann, H; Feldbaum, D; Feroz, F; Ferrante, I; Fidecaro, F; Finn, L S; Fiori, I; Fisher, R P; Flaminio, R; Flanigan, M; Foley, S; Forsi, E; Forte, L A; Fotopoulos, N; Fournier, J -D; Franc, J; Frasca, S; Frasconi, F; Frede, M; Frei, M; Frei, Z; Freise, A; Frey, R; Fricke, T T; Friedrich, D; Fritschel, P; Frolov, V V; Fujimoto, M -K; Fulda, P J; Fyffe, M; Gair, J; Galimberti, M; Gammaitoni, L; Garcia, J; Garufi, F; Gaspar, M E; Gemme, G; Geng, R; Genin, E; Gennai, A; Gergely, L A; Ghosh, S; Giaime, J A; Giampanis, S; Giardina, K D; Giazotto, A; Gil, S; Gill, C; Gleason, J; Goetz, E; Goggin, L M; Gonzalez, G; Gorodetsky, M L; Gossler, S; Gouaty, R; Graef, C; Graff, P B; Granata, M; Grant, A; Gras, S; Gray, C; Gray, N; Greenhalgh, R J S; Gretarsson, A M; Greverie, C; Grosso, R; Grote, H; Grunewald, S; Guidi, G M; Gupta, R; Gustafson, E K; Gustafson, R; Ha, T; Hallam, J M; Hammer, D; Hammond, G; Hanks, J; Hanna, C; Hanson, J; Harms, J; Harry, G M; Harry, I W; Harstad, E D; Hartman, M T; Haughian, K; Hayama, K; Hayau, J -F; Heefner, J; Heidmann, A; Heintze, M C; Heitmann, H; Hello, P; Hendry, M A; Heng, I S; Heptonstall, A W; Herrera, V; Hewitson, M; Hild, S; Hoak, D; Hodge, K A; Holt, K; Holtrop, M; Hong, T; Hooper, S; Hosken, D J; Hough, J; Howell, E J; Hughey, B; Husa, S; Huttner, S H; Inta, R; Isogai, T; Ivanov, A; Izumi, K; Jacobson, M; James, E; Jang, Y J; Jaranowski, P; Jesse, E; Johnson, W W; Jones, D I; Jones, G; Jones, R; Ju, L; Kalmus, P; Kalogera, V; Kandhasamy, S; Kang, G; Kanner, J B; Kasturi, R; Katsavounidis, E; Katzman, W; Kaufer, H; Kawabe, K; Kawamura, S; Kawazoe, F; Kelley, D; Kells, W; Keppel, D G; Keresztes, Z; Khalaidovski, A; Khalili, F Y; Khazanov, E A; Kim, B; Kim, C; Kim, H; Kim, K; Kim, N; Kim, Y -M; King, P J; Kinzel, D L; Kissel, J S; Klimenko, S; Kokeyama, K; Kondrashov, V; Koranda, S; Korth, W Z; Kowalska, I; Kozak, D; Kranz, O; Kringel, V; Krishnamurthy, S; Krishnan, B; Krolak, A; Kuehn, G; Kumar, R; Kwee, P; Lam, P K; Landry, M; Lantz, B; Lastzka, N; Lawrie, C; Lazzarini, A; Leaci, P; Lee, C H; Lee, H K; Lee, H M; Leong, J R; Leonor, I; Leroy, N; Letendre, N; Li, J; Li, T G F; Liguori, N; Lindquist, P E; Liu, Y; Liu, Z; Lockerbie, N A; Lodhia, D; Lorenzini, M; Loriette, V; Lormand, M; Losurdo, G; Lough, J; Luan, J; Lubinski, M; Luck, H; Lundgren, A P; Macdonald, E; Machenschalk, B; MacInnis, M; Macleod, D M; Mageswaran, M; Mailand, K; Majorana, E; Maksimovic, I; Man, N; Mandel, I; Mandic, V; Mantovani, M; Marandi, A; Marchesoni, F; Marion, F; Marka, S; Marka, Z; Markosyan, A; Maros, E; Marque, J; Martelli, F; Martin, I W; Martin, R M; Marx, J N; Mason, K; Masserot, A; Matichard, F; Matone, L; Matzner, R A; Mavalvala, N; Mazzolo, G; McCarthy, R; McClelland, D E; McGuire, S C; McIntyre, G; McIver, J; McKechan, D J A; McWilliams, S; Meadors, G D; Mehmet, M; Meier, T; Melatos, A; Melissinos, A C; Mendell, G; Mercer, R A; Meshkov, S; Messenger, C; Meyer, M S; Michel, C; Milano, L; Miller, J; Minenkov, Y; Mitrofanov, V P; Mitselmakher, G; Mittleman, R; Miyakawa, O; Moe, B; Mohan, M; Mohanty, S D; Mohapatra, S R P; Moreno, G; Morgado, N; Morgia, A; Mori, T; Morriss, S R; Mosca, S; Mossavi, K; Mours, B; Mow-Lowry, C M; Mueller, C L; Mueller, G; Mukherjee, S; Mullavey, A; Muller-Ebhardt, H; Munch, J; Murphy, D; Murray, P G; Mytidis, A; Nash, T; Naticchioni, L; Necula, V; Nelson, J; Newton, G; Nguyen, T; Nishizawa, A; Nitz, A; Nocera, F; Nolting, D; Normandin, M E; Nuttall, L; Ochsner, E; O'Dell, J; Oelker, E; Ogin, G H; Oh, J J; Oh, S H; O'Reilly, B; O'Shaughnessy, R; Osthelder, C; Ott, C D; Ottaway, D J; Ottens, R S; Overmier, H; Owen, B J; Page, A; Pagliaroli, G; Palladino, L; Palomba, C; Pan, Y; Pankow, C; Paoletti, F; Papa, M A; Parisi, M; Pasqualetti, A; Passaquieti, R; Passuello, D; Patel, P; Pedraza, M; Peiris, P; Pekowsky, L; Penn, S; Perreca, A; Persichetti, G; Phelps, M; Pickenpack, M; Piergiovanni, F; Pietka, M; Pinard, L; Pinto, I M; Pitkin, M; Pletsch, H J; Plissi, M V; Poggiani, R; Pold, J; Postiglione, F; Prato, M; Predoi, V; Prestegard, T; Price, L R; Prijatelj, M; Principe, M; Privitera, S; Prix, R; Prodi, G A; Prokhorov, L G; Puncken, O; Punturo, M; Puppo, P; Quetschke, V; Quitzow-James, R; Raab, F J; Rabeling, D S; Racz, I; Radkins, H; Raffai, P; Rakhmanov, M; Rankins, B; Rapagnani, P; Raymond, V; Re, V; Redwine, K; Reed, C M; Reed, T; Regimbau, T; Reid, S; Reitze, D H; Ricci, F; Riesen, R; Riles, K; Robertson, N A; Robinet, F; Robinson, C; Robinson, E L; Rocchi, A; Roddy, S; Rodriguez, C; Rodruck, M; Rolland, L; Rollins, J G; Romano, J D; Romano, R; Romie, J H; Rosinska, D; Rover, C; Rowan, S; Rudiger, A; Ruggi, P; Ryan, K; Sainathan, P; Salemi, F; Sammut, L; Sandberg, V; Sannibale, V; Santamaria, L; Santiago-Prieto, I; Santostasi, G; Sassolas, B; Sathyaprakash, B S; Sato, S; Saulson, P R; Savage, R L; Schilling, R; Schnabel, R; Schofield, R M S; Schreiber, E; Schulz, B; Schutz, B F; Schwinberg, P; Scott, J; Scott, S M; Seifert, F; Sellers, D; Sentenac, D; Sergeev, A; Shaddock, D A; Shaltev, M; Shapiro, B; Shawhan, P; Shoemaker, D H; Sibley, A; Siemens, X; Sigg, D; Singer, A; Singer, L; Sintes, A M; Skelton, G R; Slagmolen, B J J; Slutsky, J; Smith, J R; Smith, M R; Smith, R J E; Smith-Lefebvre, N D; Somiya, K; Sorazu, B; Soto, J; Speirits, F C; Sperandio, L; Stefszky, M; Stein, A J; Stein, L C; Steinert, E; Steinlechner, J; Steinlechner, S; Steplewski, S; Stochino, A; Stone, R; Strain, K A; Strigin, S E; Stroeer, A S; Sturani, R; Stuver, A L; Summerscales, T Z; Sung, M; Susmithan, S; Sutton, P J; Swinkels, B; Tacca, M; Taffarello, L; Talukder, D; Tanner, D B; Tarabrin, S P; Taylor, J R; Taylor, R; Thomas, P; Thorne, K A; Thorne, K S; Thrane, E; Thuring, A; Tokmakov, K V; Tomlinson, C; Toncelli, A; Tonelli, M; Torre, O; Torres, C; Torrie, C I; Tournefier, E; Travasso, F; Traylor, G; Tseng, K; Ugolini, D; Vahlbruch, H; Vajente, G; Brand, J F J van den; Broeck, C Van Den; van der Putten, S; van Veggel, A A; Vass, S; Vasuth, M; Vaulin, R; Vavoulidis, M; Vecchio, A; Vedovato, G; Veitch, J; Veitch, P J; Veltkamp, C; Verkindt, D; Vetrano, F; Vicere, A; Villar, A E; Vinet, J -Y; Vitale, S; Vitale, S; Vocca, H; Vorvick, C; Vyatchanin, S P; Wade, A; Wade, L; Wade, M; Waldman, S J; Wallace, L; Wan, Y; Wang, M; Wang, X; Wang, Z; Wanner, A; Ward, R L; Was, M; Weinert, M; Weinstein, A J; Weiss, R; Wen, L; Wessels, P; West, M; Westphal, T; Wette, K; Whelan, J T; Whitcomb, S E; White, D J; Whiting, B F; Wilkinson, C; Willems, P A; Williams, L; Williams, R; Willke, B; Winkelmann, L; Winkler, W; Wipf, C C; Wiseman, A G; Wittel, H; Woan, G; Wooley, R; Worden, J; Yakushin, I; Yamamoto, H; Yamamoto, K; Yamamoto, K; Yancey, C C; Yang, H; Yeaton-Massey, D; Yoshida, S; Yu, P; Yvert, M; Zadrozny, A; Zanolin, M; Zendri, J -P; Zhang, F; Zhang, L; Zhang, W; Zhao, C; Zotov, N; Zucker, M E; Zweizig, J

    2012-01-01

    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.

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

    Science.gov (United States)

    Blackburn, L.; Camp, J. B.; Cannizzo, J.; Stroeer, A. S.

    2012-01-01

    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 Mass 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 Mass , for non-spinning sources, the rate density upper limit is 0.13 per Mpc(exp 3) per Myr at the 90% confidence level.

  7. Cosmological black holes and white holes with time-dependent mass

    CERN Document Server

    da Silva, Alan M; Molina, C

    2015-01-01

    We consider the causal structure of generalized uncharged McVittie spacetimes with increasing central mass $m (t)$ and positive Hubble factor $H (t)$. Under physically reasonable conditions, namely, a big bang singularity in the past, a positive cosmological constant and an upper limit to the central mass, we prove that the patch of the spacetime described by the cosmological time and areal radius coordinates is always geodesically incomplete, which implies the presence of event horizons in the spacetime. We also show that, depending on the asymptotic behavior of the $m$ and $H$ functions, the generalized McVittie spacetime can have a single black hole, a black-hole/white-hole pair or, differently from classic fixed-mass McVittie, a single white hole. A simple criterion is given to distinguish the different causal structures.

  8. Two stellar-mass black holes in the globular cluster M22.

    Science.gov (United States)

    Strader, Jay; Chomiuk, Laura; Maccarone, Thomas J; Miller-Jones, James C A; Seth, Anil C

    2012-10-04

    Hundreds of stellar-mass black holes probably form in a typical globular star cluster, with all but one predicted to be ejected through dynamical interactions. Some observational support for this idea is provided by the lack of X-ray-emitting binary stars comprising one black hole and one other star ('black-hole/X-ray binaries') in Milky Way globular clusters, even though many neutron-star/X-ray binaries are known. Although a few black holes have been seen in globular clusters around other galaxies, the masses of these cannot be determined, and some may be intermediate-mass black holes that form through exotic mechanisms. Here we report the presence of two flat-spectrum radio sources in the Milky Way globular cluster M22, and we argue that these objects are black holes of stellar mass (each ∼10-20 times more massive than the Sun) that are accreting matter. We find a high ratio of radio-to-X-ray flux for these black holes, consistent with the larger predicted masses of black holes in globular clusters compared to those outside. The identification of two black holes in one cluster shows that ejection of black holes is not as efficient as predicted by most models, and we argue that M22 may contain a total population of ∼5-100 black holes. The large core radius of M22 could arise from heating produced by the black holes.

  9. X-ray Timing of Stellar Mass Black Holes

    CERN Document Server

    Tomsick, John A; Homan, Jeroen; Kaaret, Philip; Barret, Didier; Schnittman, Jeremy

    2009-01-01

    X-ray timing observations of accreting stellar mass black holes have shown that they can produce signals with such short time scales that we must be probing very close to the innermost stable circular orbit that is predicted by the theory of General Relativity (GR). These signals are quasi-periodic oscillations (QPOs), and both the high-frequency variety (HFQPOs, which have frequencies in the 40-450 Hz range) as well as the 0.1-10 Hz low-frequency type have the potential to provide tests of GR in the strong field limit. An important step on the path to GR tests is to constrain the physical black hole properties, and the straightforward frequency measurements that are possible with X-ray timing may provide one of the cleanest measurements of black hole spins. While current X-ray satellites have uncovered these phenomenona, the HFQPOs are weak signals, and future X-ray timing missions with larger effective area are required for testing the candidate theoretical QPO mechanisms. Another main goal in the study of ...

  10. Radio Detections During Two State Transitions of the Intermediate-Mass Black Hole HLX-1

    Science.gov (United States)

    Webb, Natalie; Cseh, David; Lenc, Emil; Godet, Olivier; Barret, Didier; Corbel, Stephane; Farrell, Sean; Fender, Robert; Gehrels, Neil; Heywood, Ian

    2012-01-01

    Relativistic jets are streams of plasma moving at appreciable fractions of the speed of light. They have been observed from stellar-mass black holes (approx. 3 to 20 solar masses) as well as supermassive black holes (approx.. 10(exp 6) to 10(exp 9) Solar Mass) found in the centers of most galaxies. Jets should also be produced by intermediate-mass black holes (approx. 10(exp 2) to 10(exp 5) Solar Mass), although evidence for this third class of black hole has, until recently, been weak. We report the detection of transient radio emission at the location of the intermediate-mass black hole candidate ESO 243-49 HLX-1, which is consistent with a discrete jet ejection event. These observations also allow us to refine the mass estimate of the black hole to be between approx. 9 × 10(exp 3) Solar Mass and approx. 9 × 10(exp 4) Solar Mass.

  11. Stellar populations across the black hole mass - velocity dispersion relation

    CERN Document Server

    Martín-Navarro, Ignacio; Bosch, Remco C E van den; Romanowsky, Aaron J; Forbes, Duncan A

    2016-01-01

    Coevolution between supermassive black holes (BHs) and their host galaxies is universally adopted in models for galaxy formation. In the absence of feedback from active galactic nuclei, simulated massive galaxies keep forming stars in the local Universe. From an observational point of view, however, such coevolution remains unclear. We present a stellar population analysis of galaxies with direct BH mass measurements and the BH mass-{\\sigma} relation as a working framework. We find that over-massive BH galaxies, i.e., galaxies lying above the best-fitting BH mass-{\\sigma} line, tend to be older and more {\\alpha}-element enhanced than under-massive BH galaxies. The scatter in the BH mass-{\\sigma}-[{\\alpha}/Fe] plane is significantly lower than in the standard BH mass-{\\sigma} relation. We interpret this trend as an imprint of active galactic nucleus feedback on the star formation histories of massive galaxies.

  12. Hairy mass bound in the Einstein-Born-Infeld black hole

    OpenAIRE

    Myung, Yun Soo; Moon, Taeyoon

    2012-01-01

    We study the Einstein-Born-Infeld (EBI) theory where the hairy black hole was found as the EBI black hole by using Hod's idea. The hair extends beyond the photon-sphere of the EBI black hole spacetimes. We show that the region beyond the photon-sphere involves more than half of the total hair's mass, which respects Hod's conjectured bound.

  13. Mass inflation inside non-Abelian black holes

    CERN Document Server

    Breitenlohner, P; Maison, D; Breitenlohner, Peter; Lavrelashvili, George; Maison, Dieter

    1997-01-01

    The interior geometry of static, spherically symmetric black holes of the Einstein-Yang-Mills-Higgs theory is analyzed. It is found that in contrast to the Abelian case generically no inner (Cauchy) horizon is formed inside non-Abelian black holes. Instead the solutions come close to a Cauchy horizon but then undergo an enormous growth of the mass function, a phenomenon which can be termed `mass inflation' in analogy to what is observed for perturbations of the Reissner-Nordstr{ø}m solution. A significant difference between the theories with and without a Higgs field is observed. Without a Higgs field the YM field induces repeated cycles of mass inflation -- taking the form of violent `explosions' -- interrupted by quiescent periods and subsequent approaches to an almost Cauchy horizon. With the Higgs field no such cycles occur. Besides the generic solutions there are non-generic families with a Schwarzschild, Reissner-Nordstr{ø}m and a pseudo Reissner-Nordstr{ø}m type singularity at $r=0$

  14. Dynamical Black Hole Masses of BL Lac Objects from the Sloan Digital Sky Survey

    NARCIS (Netherlands)

    Plotkin, Richard M.; Markoff, Sera; Trager, Scott C.; Anderson, Scott F.

    2012-01-01

    We measure black hole masses for 71 BL Lac objects from the Sloan Digital Sky Survey (SDSS) with redshifts out to z ∼ 0.4. We perform spectral decompositions of their nuclei from their host galaxies and measure their stellar velocity dispersions. Black hole masses are then derived from the black hol

  15. Dynamical black hole masses of BL Lac objects from the Sloan Digital Sky Survey

    NARCIS (Netherlands)

    Plotkin, R. M.; Markoff, S.; Trager, S. C.; Anderson, S. F.

    2011-01-01

    We measure black hole masses for 71 BL Lac objects from the Sloan Digital Sky Survey with redshifts out to z similar to 0.4. We perform spectral decompositions of their nuclei from their host galaxies and measure their stellar velocity dispersions. Black hole masses are then derived from the black h

  16. Precise Masses of Black Holes in the Nuclei of Nearby Active Galaxies

    Science.gov (United States)

    Braatz, James A., III; Kuo, C.; Greene, J.; Condon, J.; Schenker, M.; Reid, M.; Impellizzeri, V.; Henkel, C.; Zaw, I.; Lo, K. Y.

    2010-01-01

    Most elliptical and bulged spiral galaxies contain a nuclear black hole having a mass that correlates with the bulge velocity dispersion (σ). This M-σ relation suggests there is a strong link between the formation of the nuclear black hole and the formation of its host galaxy. The relationship, however, is poorly constrained for low-mass (measurements. In addition, optically measured BH masses can be uncertain by a factor of a few. Water vapor masers in the nuclei of AGN can trace the rotation curve of gas directly in the black hole's sphere of influence, and provide precise black hole masses (uncertainty measurements of black hole masses. Here we present recent VLBI maser maps and black hole masses measured as part of this program.

  17. The mass of the black hole in LMC X-3

    CERN Document Server

    Val-Baker, A K F; Negueruela, I

    2016-01-01

    New high resolution, optical spectroscopy of the high mass X-ray binary LMC X-3, shows the spectral type of the donor star changes with phase due to irradiation by the X-ray source. We find the spectral type is likely to be B5V, and only appears as B3V when viewing the heated side of the donor. Combining our measurements with those previously published, and taking into account the effects of X-ray irradiation, results in a value for the donor star radial velocity semi-amplitude of 256.7 +/- 4.9 km/s. We find the mass of the black hole lies in the range 9.5 - 13.6 solar masses.

  18. Shedding light on the black hole mass spectrum

    CERN Document Server

    Spera, Mario; Mapelli, Michela

    2016-01-01

    The mass spectrum of stellar black holes (BHs) is highly uncertain. Theoretical models of BH formation strongly depend on the efficiency of stellar winds of the progenitor star and on the supernova (SN) explosion mechanism. We discuss the BH mass spectrum we obtain using SEVN, a new public population-synthesis code that includes up-to-date stellar-wind prescriptions and several SN explosion models. Our models indicate a sub-solar metallicity environment for the progenitors of the gravitational wave source GW150914. We show that our models predict substantially larger BH masses (up to ~100 Msun) than other population synthesis codes, at low metallicity. In this proceeding, we also discuss the impact of pair-instability SNe on our previously published models.

  19. The Masses and Spins of Neutron Stars and Stellar-Mass Black Holes

    CERN Document Server

    Miller, M Coleman

    2014-01-01

    Stellar-mass black holes and neutron stars represent extremes in gravity, density, and magnetic fields. They therefore serve as key objects in the study of multiple frontiers of physics. In addition, their origin (mainly in core-collapse supernovae) and evolution (via accretion or, for neutron stars, magnetic spindown and reconfiguration) touch upon multiple open issues in astrophysics. In this review, we discuss current mass and spin measurements and their reliability for neutron stars and stellar-mass black holes, as well as the overall importance of spins and masses for compact object astrophysics. Current masses are obtained primarily through electromagnetic observations of binaries, although future microlensing observations promise to enhance our understanding substantially. The spins of neutron stars are straightforward to measure for pulsars, but the birth spins of neutron stars are more difficult to determine. In contrast, even the current spins of stellar-mass black holes are challenging to measure. ...

  20. Black hole mass, jet power and accretion in AGN

    CERN Document Server

    Chen, Yong-Yun; Xiong, Dingrong; Yu, Xiaoling

    2015-01-01

    We study the relation between accretion, black hole mass and jet power in AGN, by using a large group of blazars detected by the Fermi Large Area Telescope and radio galaxies. Our main results are as follows. (i) The jet power of FSRQs and FRII-HEG depends on the black hole mass, which suggests that the FSRQs and FRII-HEG are in Radiation-Pressure Dominated regime. The jet power of BL Lacs and FRI-LEG depends on the accretion, which suggests that the BL Lacs and FRI-LEG are in the Gas-Pressure Dominated regime. (ii) We find that most of FSRQs and BL Lacs have $\\rm{P_{jet}>L_{BZ}^{max}}$, which suggests that the Blandford-Znajek mechanism is insufficient to explain the jet power of these objects. (iii) The FSRQs are roughly separated from BL Lacs by the Ledlow-Owen's dividing line in the $\\rm{\\log P_{jet}-\\log M}$ plane, which supports the unified scheme of AGN. (iv) The FSRQs and BL Lacs have a clear division at $\\rm{L_{bol}/L_{Edd}\\sim0.01}$, and the distribution of Eddington ratios of BL Lacs and FSRQs exhi...

  1. Radio detections during two state transitions of the intermediate-mass black hole HLX-1.

    Science.gov (United States)

    Webb, Natalie; Cseh, David; Lenc, Emil; Godet, Olivier; Barret, Didier; Corbel, Stephane; Farrell, Sean; Fender, Robert; Gehrels, Neil; Heywood, Ian

    2012-08-01

    Relativistic jets are streams of plasma moving at appreciable fractions of the speed of light. They have been observed from stellar-mass black holes (~3 to 20 solar masses, M(⊙)) as well as supermassive black holes (~10(6) to 10(9) M(⊙)) found in the centers of most galaxies. Jets should also be produced by intermediate-mass black holes (~10(2) to 10(5) M(⊙)), although evidence for this third class of black hole has, until recently, been weak. We report the detection of transient radio emission at the location of the intermediate-mass black hole candidate ESO 243-49 HLX-1, which is consistent with a discrete jet ejection event. These observations also allow us to refine the mass estimate of the black hole to be between ~9 × 10(3) M(⊙) and ~9 × 10(4) M(⊙).

  2. Two ten-billion-solar-mass black holes at the centres of giant elliptical galaxies.

    Science.gov (United States)

    McConnell, Nicholas J; Ma, Chung-Pei; Gebhardt, Karl; Wright, Shelley A; Murphy, Jeremy D; Lauer, Tod R; Graham, James R; Richstone, Douglas O

    2011-12-08

    Observational work conducted over the past few decades indicates that all massive galaxies have supermassive black holes at their centres. Although the luminosities and brightness fluctuations of quasars in the early Universe suggest that some were powered by black holes with masses greater than 10 billion solar masses, the remnants of these objects have not been found in the nearby Universe. The giant elliptical galaxy Messier 87 hosts the hitherto most massive known black hole, which has a mass of 6.3 billion solar masses. Here we report that NGC 3842, the brightest galaxy in a cluster at a distance from Earth of 98 megaparsecs, has a central black hole with a mass of 9.7 billion solar masses, and that a black hole of comparable or greater mass is present in NGC 4889, the brightest galaxy in the Coma cluster (at a distance of 103 megaparsecs). These two black holes are significantly more massive than predicted by linearly extrapolating the widely used correlations between black-hole mass and the stellar velocity dispersion or bulge luminosity of the host galaxy. Although these correlations remain useful for predicting black-hole masses in less massive elliptical galaxies, our measurements suggest that different evolutionary processes influence the growth of the largest galaxies and their black holes.

  3. Biases in Virial Black Hole Masses: An SDSS Perspective

    CERN Document Server

    Shen, Yue; Strauss, Michael; Richards, Gordon T; Schneider, Donald P

    2007-01-01

    We compile black hole (BH) masses for $\\sim 60,000$ quasars in the redshift range $0.1 \\lesssim z \\lesssim 4.5$ included in the Fifth Data Release of the Sloan Digital Sky Survey (SDSS), using virial BH mass estimators based on the \\hbeta, \\MgII, and \\CIV emission lines. We find that: (1) within our sample, the widths of the three lines follow log-normal distributions, with means and dispersions that do not depend strongly on luminosity or redshift;(2) the \\MgII- and \\hbeta-estimated BH masses are consistent with one another; and (3) the \\CIV BH mass estimator may be more severely affected by a disk wind component than the \\MgII and \\hbeta estimators, giving a positive bias in mass correlated with the \\CIV-\\MgII blueshift. Most SDSS quasars have virial BH masses in the range $10^8-10^9 M_\\odot$. There is a clear upper mass limit of $\\sim 3\\times 10^9-10^{10} M_\\odot$ for active BHs at $z \\gtrsim 2$, decreasing at lower redshifts. Making the reasonable assumptions that the underlying BH mass distribution decre...

  4. An intermediate-mass black hole in the centre of the globular cluster 47 Tucanae.

    Science.gov (United States)

    Kızıltan, Bülent; Baumgardt, Holger; Loeb, Abraham

    2017-02-08

    Intermediate-mass black holes should help us to understand the evolutionary connection between stellar-mass and super-massive black holes. However, the existence of intermediate-mass black holes is still uncertain, and their formation process is therefore unknown. It has long been suspected that black holes with masses 100 to 10,000 times that of the Sun should form and reside in dense stellar systems. Therefore, dedicated observational campaigns have targeted globular clusters for many decades, searching for signatures of these elusive objects. All candidate signatures appear radio-dim and do not have the X-ray to radio flux ratios required for accreting black holes. Based on the lack of an electromagnetic counterpart, upper limits of 2,060 and 470 solar masses have been placed on the mass of a putative black hole in 47 Tucanae (NGC 104) from radio and X-ray observations, respectively. Here we show there is evidence for a central black hole in 47 Tucanae with a mass of solar masses when the dynamical state of the globular cluster is probed with pulsars. The existence of an intermediate-mass black hole in the centre of one of the densest clusters with no detectable electromagnetic counterpart suggests that the black hole is not accreting at a sufficient rate to make it electromagnetically bright and therefore, contrary to expectations, is gas-starved. This intermediate-mass black hole might be a member of an electromagnetically invisible population of black holes that grow into supermassive black holes in galaxies.

  5. An intermediate-mass black hole in the centre of the globular cluster 47 Tucanae

    Science.gov (United States)

    Kızıltan, Bülent; Baumgardt, Holger; Loeb, Abraham

    2017-02-01

    Intermediate-mass black holes should help us to understand the evolutionary connection between stellar-mass and super-massive black holes. However, the existence of intermediate-mass black holes is still uncertain, and their formation process is therefore unknown. It has long been suspected that black holes with masses 100 to 10,000 times that of the Sun should form and reside in dense stellar systems. Therefore, dedicated observational campaigns have targeted globular clusters for many decades, searching for signatures of these elusive objects. All candidate signatures appear radio-dim and do not have the X-ray to radio flux ratios required for accreting black holes. Based on the lack of an electromagnetic counterpart, upper limits of 2,060 and 470 solar masses have been placed on the mass of a putative black hole in 47 Tucanae (NGC 104) from radio and X-ray observations, respectively. Here we show there is evidence for a central black hole in 47 Tucanae with a mass of solar masses when the dynamical state of the globular cluster is probed with pulsars. The existence of an intermediate-mass black hole in the centre of one of the densest clusters with no detectable electromagnetic counterpart suggests that the black hole is not accreting at a sufficient rate to make it electromagnetically bright and therefore, contrary to expectations, is gas-starved. This intermediate-mass black hole might be a member of an electromagnetically invisible population of black holes that grow into supermassive black holes in galaxies.

  6. Analytic study of mass segregation around a massive black hole

    CERN Document Server

    Keshet, Uri; Alexander, Tal

    2009-01-01

    We analyze the distribution of stars of arbitrary mass function g(m) around a massive black hole (MBH). Unless g is strongly dominated by light stars, the steady-state distribution function approaches a power-law in specific energy x=-E/(m*sigma^2)mass averaged over m*g*x_{max}^p. For light-dominated g, p becomes non-linear in m and can grow as large as 3/2 - much steeper than previously thought. A simple prescription for the stellar density profile around MBHs is provided.

  7. Mass inflation and chaotic behaviour inside hairy black holes

    Science.gov (United States)

    Breitenlohner, Peter; Lavrelashvili, George; Maison, Dieter

    1998-07-01

    We analyze the interior geometry of static, spherically symmetric black holes of the Einstein-Yang-Mills-Higgs theory. Generically the solutions exhibit a behaviour that may be described as ``mass inflation'', although with a remarkable difference between the cases with and without a Higgs field. Without Higgs field the YM field induces a kind of cyclic behaviour leading to repeated cycles of mass inflation - taking the form of violent explosions - interrupted by quiescent periods and subsequent approaches to an almost Cauchy horizon. With the Higgs field no such cycles occur in the asymptotic behaviour. In addition there are non-generic families with a Schwarzschild and a Reissner-Nordstrøm type singularity at r=0, respectively.

  8. Determining Central Black Hole Masses in Distant Active Galaxies

    DEFF Research Database (Denmark)

    Vestergaard, Marianne

    2002-01-01

    of a factor less than 2 in the primary methods used to measure the central masses of nearby inactive and active galaxies, namely resolved gas and stellar kinematics in the underlying host galaxy and reverberation-mapping techniques. The UV relationship holds good potential for being a powerful tool to study...... stresses the need for better observational constraints to be placed on this relationship. The empirically calibrated relationships presented here will be applied to quasar samples in forthcoming work.......An empirical relationship, of particular interest for studies of high redshift active galactic nuclei (AGNs) and quasars, between the masses of their central black-holes and rest-frame ultraviolet (UV) parameters measured in single-epoch AGN spectra is presented. This relationship is calibrated...

  9. The Future of Direct Supermassive Black Hole Mass Estimates

    CERN Document Server

    Batcheldor, D

    2009-01-01

    (Abridged) The repeated discovery of supermassive black holes (SMBHs) at the centers of galactic bulges, and the discovery of relations between the SMBH mass (M) and the properties of these bulges, has been fundamental in directing our understanding of both galaxy and SMBH formation and evolution. However, there are still many questions surrounding the SMBH - galaxy relations. For example, are the scaling relations linear and constant throughout cosmic history, and do all SMBHs lie on the scaling relations? These questions can only be answered by further high quality direct M estimates from a wide range in redshift. In this paper we determine the observational requirements necessary to directly determine SMBH masses, across cosmological distances, using current M modeling techniques. We also discuss the SMBH detection abilities of future facilities. We find that if different M modeling techniques, using different spectral features, can be shown to be consistent, then both 30 m ground- and 16 m space-based tel...

  10. A lower bound for the mass of axisymmetric connected black hole data sets

    CERN Document Server

    Chruściel, Piotr T

    2011-01-01

    We present a generalisation of the Brill-type proof of positivity of mass for axisymmetric initial data to initial data sets with black hole boundaries. The argument leads to a strictly positive lower bound for the mass of simply connected, connected axisymmetric black hole data sets in terms of the mass of a reference Schwarzschild metric.

  11. Determining Central Black Hole Masses in Distant Active Galaxies

    CERN Document Server

    Vestergaard, M

    2002-01-01

    An empirical relationship, of particular interest for studies of high redshift active galactic nuclei (AGNs) and quasars, between the masses of their central black-holes and rest-frame ultraviolet (UV) parameters measured in single-epoch AGN spectra is presented. This relationship is calibrated to recently measured reverberation masses of low-redshift AGNs and quasars. An empirical relationship between single-epoch rest-frame optical spectrophotometric measurements and the central masses is also presented. The UV relationship allows reasonable estimates of the central masses to be made of high-redshift AGNs and quasars for which these masses cannot be directly or easily measured by the techniques applicable to the lower luminosity, nearby AGNs. The central mass obtained by this method can be estimated to within a factor of ~3 for most objects. This is reasonable given the intrinsic uncertainty of a factor less than 2 in the primary methods used to measure the central masses of nearby inactive and active galax...

  12. Hairy mass bound in the Einstein-Born-Infeld black hole

    CERN Document Server

    Myung, Yun Soo

    2012-01-01

    We study the Einstein-Born-Infeld (EBI) theory where hairy black hole was found as the EBI black hole by using Hod's idea. The hair extends beyond the photon-sphere of the EBI black hole spacetimes. We show that the region beyond the photon-sphere involves more than half of the total hair's mass. However, the hairy mass bound proposed by Hod is not suitable for accounting the hair (EBIon) distributed in the whole spacetimes. Hence, we propose a new hairy mass bound for the EBI black hole.

  13. Stellar-mass black holes and ultraluminous x-ray sources.

    Science.gov (United States)

    Fender, Rob; Belloni, Tomaso

    2012-08-03

    We review the likely population, observational properties, and broad implications of stellar-mass black holes and ultraluminous x-ray sources. We focus on the clear empirical rules connecting accretion and outflow that have been established for stellar-mass black holes in binary systems in the past decade and a half. These patterns of behavior are probably the keys that will allow us to understand black hole feedback on the largest scales over cosmological time scales.

  14. The connection between black hole mass and Doppler boosted emission in BL Lacertae type objects

    OpenAIRE

    Leon-Tavares, J.; Valtaoja, E.; V. H. Chavushyan; Tornikoski, M.; Anorve, C.; Nieppola, E.; Lahteenmaki, A.

    2010-01-01

    We investigate the relationship between black hole mass (MBH) and Doppler boosted emission for BL Lacertae type objects (BL Lacs) detected in the SDSS and FIRST surveys. The synthesis of stellar population and bidimensional decomposition methods allows us to disentangle the components of the host galaxy from that of the nuclear black hole in their optical spectra and images, respectively. We derive estimates of black hole masses via stellar velocity dispersion and bulge luminosity. We find th...

  15. Correcting CIV-Based Virial Black Hole Masses

    CERN Document Server

    Coatman, Liam; Banerji, Manda; Richards, Gordon T; Hennawi, Joseph F; Prochaska, J Xavier

    2016-01-01

    The CIV broad emission line is visible in optical spectra to redshifts exceeding z~5. CIV has long been known to exhibit significant displacements to the blue and these `blueshifts' almost certainly signal the presence of strong outflows. As a consequence, single-epoch virial black hole (BH) mass estimates derived from CIV velocity-widths are known to be systematically biased compared to masses from the hydrogen Balmer lines. Using a large sample of 230 high-luminosity (log $L_{\\rm Bol}$ = 45.5-48 erg/s), redshift 1.55000 km/s. Using the monotonically increasing relationship between the CIV blueshift and the mass ratio BH(CIV)/BH(H$\\alpha$) we derive an empirical correction to all CIV BH-masses. The scatter between the corrected CIV masses and the Balmer masses is 0.24 dex at low CIV blueshifts (~0 km/s) and just 0.10 dex at high blueshifts (~3000 km/s), compared to 0.40 dex before the correction. The correction depends only on the CIV line properties - i.e. full-width at half maximum and blueshift - and can ...

  16. Correcting C IV-based virial black hole masses

    Science.gov (United States)

    Coatman, Liam; Hewett, Paul C.; Banerji, Manda; Richards, Gordon T.; Hennawi, Joseph F.; Prochaska, J. Xavier

    2017-02-01

    The C IVλλ1498,1501 broad emission line is visible in optical spectra to redshifts exceeding z ˜ 5. C IV has long been known to exhibit significant displacements to the blue and these `blueshifts' almost certainly signal the presence of strong outflows. As a consequence, single-epoch virial black hole (BH) mass estimates derived from C IV velocity widths are known to be systematically biased compared to masses from the hydrogen Balmer lines. Using a large sample of 230 high-luminosity (LBol = 1045.5-1048 erg s-1), redshift 1.5 < z < 4.0 quasars with both C IV and Balmer line spectra, we have quantified the bias in C IV BH masses as a function of the C IV blueshift. C IV BH masses are shown to be a factor of 5 larger than the corresponding Balmer-line masses at C IV blueshifts of 3000 km s-1and are overestimated by almost an order of magnitude at the most extreme blueshifts, ≳5000 km s-1. Using the monotonically increasing relationship between the C IV blueshift and the mass ratio BH(C IV)/BH(Hα), we derive an empirical correction to all C IV BH masses. The scatter between the corrected C IV masses and the Balmer masses is 0.24 dex at low C IV blueshifts (˜0 km s-1) and just 0.10 dex at high blueshifts (˜3000 km s-1), compared to 0.40 dex before the correction. The correction depends only on the C IV line properties - i.e. full width at half-maximum and blueshift - and can therefore be applied to all quasars where C IV emission line properties have been measured, enabling the derivation of unbiased virial BH-mass estimates for the majority of high-luminosity, high-redshift, spectroscopically confirmed quasars in the literature.

  17. Neutrino pair annihilation near accreting, stellar-mass black holes

    CERN Document Server

    Birkl, R; Janka, H T; Müller, E

    2006-01-01

    We investigate the energy-momentum deposition due to neutrino-antineutrino annihilation in the vicinity of axisymmetric, accreting black holes (BHs) by numerically ray-tracing neutrino trajectories in a Kerr space-time. Hyperaccreting stellar-mass BHs are widely considered as energy sources that can drive ultrarelativistic outflows with the potential to produce gamma-ray bursts. In contrast to earlier works, we provide an extensive and detailed parameter study of the influence of general relativistic (GR) effects and of different neutrinosphere geometries. These include idealized thin disks, tori, and spheres, or are constructed as non-selfgravitating equilibrium matter distributions for varied BH rotation. Considering isothermal neutrinospheres with the same temperature and surface area, we confirm previous results that compared to Newtonian calculations, GR effects increase the annihilation rate measured by an observer at infinity by a factor of 2 when the neutrinosphere is a disk. However, in case of a tor...

  18. Novel Approach to the Dark Matter Problem: Primordial Intermediate-Mass Black Holes

    CERN Document Server

    Frampton, Paul H

    2016-01-01

    A discussion at a Scientific American level of the idea that the constituents of the dark mater in galactic halos are primordial intermediate-mass black holes with masses between ten and one hundred thousand times the solar mass.

  19. LISA extreme-mass-ratio inspiral events as probes of the black hole mass function

    CERN Document Server

    Gair, Jonathan R; Volonteri, Marta

    2010-01-01

    One of the sources of gravitational waves for the proposed space-based gravitational wave detector, the Laser Interferometer Space Antenna (LISA), are the inspirals of compact objects into supermassive black holes in the centres of galaxies - extreme-mass-ratio inspirals (EMRIs). Using LISA observations, we will be able to measure the parameters of each EMRI system detected to very high precision. However, the statistics of the set of EMRI events observed by LISA will be more important in constraining astrophysical models than extremely precise measurements for individual systems. The black holes to which LISA is most sensitive are in a mass range that is difficult to probe using other techniques, so LISA provides an almost unique window onto these objects. In this paper we explore, using Bayesian techniques, the constraints that LISA EMRI observations can place on the mass function of black holes at low redshift. We describe a general framework for approaching inference of this type --- using multiple observ...

  20. Supermassive Black Holes in Active Galactic Nuclei. II. Calibration of the Black Hole Mass-Velocity Dispersion Relationship for Active Galactic Nuclei

    DEFF Research Database (Denmark)

    Onken, Christopher A.; Ferrarese, Laura; Merritt, David

    2004-01-01

    We calibrate reverberation-based black hole masses in active galactic nuclei (AGNs) by using the correlation between black hole mass, M, and bulge/spheroid stellar velocity dispersion, sigma. We use new measurements of sigma for 6 AGNs and published velocity dispersions for 10 others......, in conjunction with improved reverberation mapping results, to determine the scaling factor required to bring reverberation-based black hole masses into agreement with the quiescent galaxy M-sigma relationship. The scatter in the AGN black hole masses is found to be less than a factor of 3. The current...

  1. A Relationship between Supermassive Black Hole Mass and the Total Gravitational Mass of the Host Galaxy

    CERN Document Server

    Bandara, Kaushala; Simard, Luc

    2009-01-01

    We investigate the correlation between the mass of a central supermassive black hole and the total gravitational mass of the host galaxy (M_tot). The results are based on 43 galaxy-scale strong gravitational lenses from the Sloan Lens ACS (SLACS) Survey whose black hole masses were estimated through two scaling relations: the relation between black hole mass and Sersic index (M_bh - n) and the relation between black hole mass and stellar velocity dispersion (M_bh - sigma). We use the enclosed mass within R_200, the radius within which the density profile of the early type galaxy exceeds the critical density of the Universe by a factor of 200, determined by gravitational lens models fitted to HST imaging data, as a tracer of the total gravitational mass. The best fit correlation, where M_bh is determined from M_bh - sigma relation, is log(M_bh) = (8.18 +/- 0.11) + (1.55 +/- 0.31) (log(M_tot) - 13.0) over 2 orders of magnitude in M_bh. From a variety of tests, we find that we cannot reliably infer a connection ...

  2. The masses and spins of neutron stars and stellar-mass black holes

    Energy Technology Data Exchange (ETDEWEB)

    Miller, M. Coleman, E-mail: miller@astro.umd.edu [University of Maryland, Department of Astronomy and Joint Space-Science Institute, College Park, MD 20742-2421 (United States); Miller, Jon M. [University of Michigan, Department of Astronomy, 500 Church Street, Ann Arbor, MI 48109-1042 (United States)

    2015-01-10

    Stellar-mass black holes and neutron stars represent extremes in gravity, density, and magnetic fields. They therefore serve as key objects in the study of multiple frontiers of physics. In addition, their origin (mainly in core-collapse supernovae) and evolution (via accretion or, for neutron stars, magnetic spindown and reconfiguration) touch upon multiple open issues in astrophysics. In this review, we discuss current mass and spin measurements and their reliability for neutron stars and stellar-mass black holes, as well as the overall importance of spins and masses for compact object astrophysics. Current masses are obtained primarily through electromagnetic observations of binaries, although future microlensing observations promise to enhance our understanding substantially. The spins of neutron stars are straightforward to measure for pulsars, but the birth spins of neutron stars are more difficult to determine. In contrast, even the current spins of stellar-mass black holes are challenging to measure. As we discuss, major inroads have been made in black hole spin estimates via analysis of iron lines and continuum emission, with reasonable agreement when both types of estimate are possible for individual objects, and future X-ray polarization measurements may provide additional independent information. We conclude by exploring the exciting prospects for mass and spin measurements from future gravitational wave detections, which are expected to revolutionize our understanding of strong gravity and compact objects.

  3. On black hole masses, radio-loudness and bulge luminosities of Seyfert galaxies

    CERN Document Server

    Wu, X B; Wu, Xue-Bing

    2001-01-01

    We estimated black hole masses for 9 Seyfert 1 and 13 Seyfert 2 galaxies in the Palomar and CfA bright Seyfert samples using the tight correlation between black hole mass and bulge velocity dispersion. Combining other 13 Seyfert 1s and 2 Seyfert 2s in these samples but with black hole masses measured recently by reverberation mapping and stellar/gas dynamics, we studied the correlations of black hole masses with radio loudness and bulge luminosities for a sample of 37 Seyfert galaxies. We found that if radio-loudness is measured using the optical and radio luminosities of the nuclear components, the black hole masses of radio-loud Seyfert 1s tend to increase with the radio-loudness. The black hole masses of all Seyfert galaxies increase with the radio power, but Seyfert galaxies have larger radio powers than nearby galaxies with the same black hole masses. In addition, the correlation between black hole masses and bulge V-band luminosities for Seyfert galaxies is consistent with that found for quasars and nor...

  4. Strong mass segregation around a massive black hole

    CERN Document Server

    Alexander, Tal

    2008-01-01

    We show that the mass-segregation solution for the steady state distribution of stars around a massive black hole (MBH) has two branches: the known weak segregation solution (Bahcall & Wolf 1977), and a newly discovered strong segregation solution, presented here. The nature of the solution depends on the heavy-to-light stellar mass ratio M_H/M_L and on the unbound population number ratio N_H/N_L, through the relaxational coupling parameter \\Delta=4 N_H M_H^2 /[N_L M_L^2(3+M_H/M_L)]. When the heavy stars are relatively common (\\Delta>>1), they scatter frequently on each other. This efficient self-coupling leads to weak mass segregation, where the stars form n \\propto r^{-\\alpha_M} mass-dependent cusps near the MBH, with indices \\alpha_H=7/4 for the heavy stars and 3/2<\\alpha_L<7/4 for the light stars (i.e. \\max(\\alpha_H-\\alpha_L)~=1/4). However, when the heavy stars are relatively rare (\\Delta<<1), they scatter mostly on light stars, sink to the center by dynamical friction and settle into a m...

  5. THE (BLACK HOLE)-BULGE MASS SCALING RELATION AT LOW MASSES

    Energy Technology Data Exchange (ETDEWEB)

    Graham, Alister W. [Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Hawthorn, VIC 3122 (Australia); Scott, Nicholas [Sydney Institute for Astronomy, School of Physics, University of Sydney, NSW 2006 (Australia)

    2015-01-01

    Several recent papers have reported on the occurrence of active galactic nuclei (AGNs) containing undermassive black holes relative to a linear scaling relation between black hole mass (M {sub bh}) and host spheroid stellar mass (M {sub sph,} {sub *}). However, dramatic revisions to the M {sub bh}-M {sub sph,} {sub *} and M {sub bh}-L {sub sph} relations, based on samples containing predominantly inactive galaxies, have recently identified a new steeper relation at M {sub bh} ≲ (2-10) × 10{sup 8} M {sub ☉}, roughly corresponding to M {sub sph,} {sub *} ≲ (0.3-1) × 10{sup 11} M {sub ☉}. We show that this steeper, quadratic-like M {sub bh}-M {sub sph,} {sub *} relation defined by the Sérsic galaxies, i.e., galaxies without partially depleted cores, roughly tracks the apparent offset of the AGN having 10{sup 5} ≲ M {sub bh}/M {sub ☉} ≲ 0.5 × 10{sup 8}. That is, these AGNs are not randomly offset with low black hole masses, but also follow a steeper (nonlinear) relation. As noted by Busch et al., confirmation or rejection of a possible AGN offset from the steeper M {sub bh}-M {sub sph,} {sub *} relation defined by the Sérsic galaxies will benefit from improved stellar mass-to-light ratios for the spheroids hosting these AGNs. Several implications for formation theories are noted. Furthermore, reasons for possible under- and overmassive black holes, the potential existence of intermediate mass black holes (<10{sup 5} M {sub ☉}), and the new steep (black hole)-(nuclear star cluster) relation, M{sub bh}∝M{sub nc}{sup 2.7±0.7}, are also discussed.

  6. The head-on collision of two equal mass black holes

    CERN Document Server

    Anninos, P; Seidel, E; Smarr, L L; Suen, W M; Hobill, David; Seidel, Edward; Smarr, Larry; Suen, Wai Mo

    1995-01-01

    We study the head-on collision of two equal mass, nonrotating black holes. Various initial configurations are investigated, including holes which are initially surrounded by a common apparent horizon to holes that are separated by about 20M, where M is the mass of a single black hole. We have extracted both \\ell = 2 and \\ell=4 gravitational waveforms resulting from the collision. The normal modes of the final black hole dominate the spectrum in all cases studied. The total energy radiated is computed using several independent methods, and is typically less than 0.002 M. We also discuss an analytic approach to estimate the total gravitational radiation emitted in the collision by generalizing point particle dynamics to account for the finite size and internal dynamics of the two black holes. The effects of the tidal deformations of the horizons are analysed using the membrane paradigm of black holes. We find excellent agreement between the numerical results and the analytic estimates.

  7. On a general class of regular rotating black holes based on a smeared mass distribution

    Directory of Open Access Journals (Sweden)

    Alexis Larranaga

    2015-04-01

    Full Text Available In this work we investigate the behavior of a new general class of rotating regular black holes based on a non-Gaussian smeared mass distribution. It is shown that the existence of a fundamental minimal length cures the well-known problems in the terminal phase of black hole evaporation, since we find that there is a finite maximum temperature that the black hole reaches before cooling down to absolute zero, so that the evaporation ends up in a zero temperature extremal black hole whose mass and size depends on the value of the fundamental length and on the rotation parameter of the black hole. We also study the geodesic structure in these spacetimes and calculate the shadows that these black holes produce.

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

    CERN Document Server

    Miller, J M

    2006-01-01

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

  9. The Masses of Black Holes with Wolf-Rayet Companions

    Science.gov (United States)

    Laycock, Silas; Steiner, James F.; Maccarone, Thomas J.; Christodoulou, Dimitris M.; Binder, Breanna A.; Yang, Jun; Cappallo, Rigel

    2016-04-01

    Black Holes with Wolf-Rayet companions represent a channel for forming the most massive stellar BHs. The recent, stunning LIGO detection of the gravitational wave signature from a merging stellar BH binary points to the importance of understanding the progenitor systems formation and evolution. The BH+WR binary IC 10 X-1 holds important clues to the puzzle, by helping establish the upper observed BH mass and pointing to an association between maximum possible BH mass and low metallicity environments. However, securing dynamical mass determiniations for WR+BH binaries appears to be complicated by interaction between the radiation field of the BH and the stellar wind. This causes a substantial change to our understanding of IC 10 X-1, and by extension to the mass distribution of BH binaries. A high precision ephemeris derived from a decade of Chandra/XMM X-ray timing observations, when combined with the optical RV curve, reveals a surprizing simultenaity of mid X-ray eclipse and the maximum blueshift velocity of He II emission lines. The optical emission lines appear to originate in a shielded sector of the WR star's stellar wind which escapes total X-ray ionization by the compact object. Unravelling this projection effect is necessary to obtain the system's true mass function. Complementary Chandra, XMM and NuStar datasets offer new insights into the mass and spin of the BH, and the structure of the photo-ionized wind. We will discuss possible routes toward the mass function in BH+WR binaries via multi-wavelength observations, and the additional leverage provided by further constraining the orbital period derivative.

  10. On Accelerated Black Holes

    CERN Document Server

    Letelier, P S; Letelier, Patricio S.; Oliveira, Samuel R.

    1998-01-01

    The C-metric is revisited and global interpretation of some associated spacetimes are studied in some detail. Specially those with two event horizons, one for the black hole and another for the acceleration. We found that the spacetime fo an accelerated Schwarzschild black hole is plagued by either conical singularities or lack of smoothness and compactness of the black hole horizon. By using standard black hole thermodynamics we show that accelerated black holes have higher Hawking temperature than Unruh temperature. We also show that the usual upper bound on the product of the mass and acceleration parameters (<1/sqrt(27)) is just a coordinate artifact. The main results are extended to accelerated Kerr black holes. We found that they are not changed by the black hole rotation.

  11. Natal Kicks of Stellar-Mass Black Holes by Asymmetric Mass Ejection in Fallback Supernovae

    CERN Document Server

    Janka, H -Thomas

    2013-01-01

    Integrating trajectories of low-mass X-ray binaries containing black holes within the Galactic potential, Repetto, Davies & Sigurdsson recently showed that the large distances of some systems above the Galactic plane can only be explained if black holes receive appreciable natal kicks. Surprisingly, they found that the distribution of black hole kick velocities (rather than that of the momenta) should be similar to that of neutron stars. Here I argue that this result can be understood if neutron star and black hole kicks are a consequence of large-scale asymmetries created in the supernova ejecta by the explosion mechanism. The corresponding anisotropic gravitational attraction of the asymmetrically expelled matter does not only accelerate new-born neutron stars by the "gravitational tug-boat mechanism". It can also lead to delayed black-hole formation by asymmetric fallback of the slowest parts of the initial ejecta onto the transiently existing neutron star, in course of which the momentum of the black ...

  12. Toward Precision Supermassive Black Hole Masses Using Megamaser Disks

    Science.gov (United States)

    van den Bosch, Remco C. E.; Greene, Jenny E.; Braatz, James A.; Constantin, Anca; Kuo, Cheng-Yu

    2016-03-01

    Megamaser disks provide the most precise and accurate extragalactic supermassive black hole (BH) masses. Here we describe a search for megamasers in nearby galaxies using the Green Bank Telescope (GBT). We focus on galaxies where we believe that we can resolve the gravitational sphere of influence of the BH and derive a stellar or gas dynamical measurement with optical or NIR observations. Since there are only a handful of super massive BHs that have direct BH mass measurements from more than one method, even a single galaxy with a megamaser disk and a stellar dynamical BH mass would provide necessary checks on the stellar dynamical methods. We targeted 87 objects from the Hobby-Eberly Telescope Massive Galaxy Survey, and detected no new maser disks. Most of the targeted objects are elliptical galaxies with typical stellar velocity dispersions of 250 km s-1 and distances within 130 Mpc. We discuss the implications of our non-detections, whether they imply a threshold X-ray luminosity required for masing, or possibly reflect the difficulty of maintaining a masing disk around much more massive (≳ {10}8 {M}⊙ ) BHs at a low Eddington ratio. Given the power of maser disks for probing BH accretion and demographics, we suggest that future maser searches should endeavour to remove remaining sample biases, in order to sort out the importance of these covariant effects.

  13. A Note on Physical Mass and the Thermodynamics of AdS-Kerr Black Holes

    CERN Document Server

    McInnes, Brett

    2015-01-01

    As with any black hole, asymptotically anti-de Sitter Kerr black holes are described by a small number of parameters, including a "mass parameter" $M$ that reduces to the AdS-Schwarzschild mass in the limit of vanishing angular momentum. In sharp contrast to the asymptotically flat case, the horizon area of such a black hole increases with the angular momentum parameter $a$ if one fixes $M$; this appears to mean that the Penrose process in this case would violate the Second Law of black hole thermodynamics. We show that the correct procedure is to fix not $M$ but rather the "physical" mass $E=M/(1-a^2/L^2)^2$; this is motivated by the First Law. For then the horizon area decreases with $a$. We recommend that $E$ always be used as the mass: for example, in attempts to "over-spin" AdS-Kerr black holes.

  14. Mass and Angular Momentum of Black Holes in Three Dimensional Gravity Theories with First Order Formalism

    CERN Document Server

    Nam, Soonkeon

    2016-01-01

    We apply the Wald formalism to obtain masses and angular momenta of black holes in three dimensional gravity theories using first order formalism. Wald formalism suggests mass and angular momentum of black hole as an integration of some charge variation form at its boundary. The action of the three dimensional gravity theories can be represented by the form including some auxiliary fields. As well-known examples we have calculated mass and angular momentum of some black holes in topologically massive gravity and new massive gravity theories using first order formalism. We have also calculated mass and angular momentum of BTZ black hole and new type black hole in minimal massive gravity theory with the action represented by first order formalism.

  15. Mass Functions of the Active Black Holes in Distant Quasars from the Sloan Digital Sky Survey Data Release 3

    DEFF Research Database (Denmark)

    Vestergaard, Marianne; Fan, X.; Tremonti, C. A.

    2007-01-01

    We present the mass functions of actively accreting supermassive black holes over the redshift range 0.3......We present the mass functions of actively accreting supermassive black holes over the redshift range 0.3...

  16. Oscillatory and Power-law Mass Inflation in Non-Abelian Black Holes

    CERN Document Server

    Galtsov, D V; Zotov, M Yu

    1997-01-01

    Interior structure of non-Abelian black holes is shown to exhibit in a general case either an oscillating mass-inflationary behavior, or power-law behavior with a divergent mass function. In both cases no Cauchy horizon forms.

  17. Powerful, Rotating Disk Winds from Stellar-mass Black Holes

    CERN Document Server

    Miller, J M; Kaastra, J; Kallman, T; King, A L; Proga, D; Raymond, J; Reynolds, C S

    2015-01-01

    We present an analysis of ionized X-ray disk winds observed in the Fe K band of four stellar-mass black holes observed with Chandra, including 4U 1630-47, GRO J1655-40, H 1743-322, and GRS 1915+105. High-resolution photoionization grids were generated in order to model the data. Third-order gratings spectra were used to resolve complex absorption profiles into atomic effects and multiple velocity components. The Fe XXV line is found to be shaped by contributions from the intercombination line (in absorption), and the Fe XXVI line is detected as a spin-orbit doublet. The data require 2-3 absorption zones, depending on the source. The fastest components have velocities approaching or exceeding 0.01c, increasing mass outflow rates and wind kinetic power by orders of magnitude over prior single-zone models. The first-order spectra require re-emission from the wind, broadened by a degree that is loosely consistent with Keplerian orbital velocities at the photoionization radius. This suggests that disk winds are ro...

  18. Dark matter haloes determine the masses of supermassive black holes

    CERN Document Server

    Booth, C M

    2009-01-01

    The energy and momentum deposited by the radiation from accretion onto the supermassive black holes (BHs) that reside at the centres of virtually all galaxies can halt or even reverse gas inflow, providing a natural mechanism for supermassive BHs to regulate their growth and to couple their properties to those of their host galaxies. However, it remains unclear whether this self-regulation occurs on the scale at which the BH is gravitationally dominant, on that of the stellar bulge, the galaxy, or that of the entire dark matter halo. To answer this question, we use self-consistent simulations of the co-evolution of the BH and galaxy populations that reproduce the observed correlations between the masses of the BHs and the properties of their host galaxies. We first confirm unambiguously that the BHs regulate their growth: the amount of energy that the BHs inject into their surroundings remains unchanged when the fraction of the accreted rest mass energy that is injected, is varied by four orders of magnitude....

  19. Black Holes across the Mass Spectrum-from Stellar Mass BH to ULXs and AGN

    Science.gov (United States)

    Mushotzky, Richard

    2006-01-01

    I will discuss the observational characteristics of black holes and how they compare across the 10^8 range in mass and as a function of luminosity and apparent Eddington ratio. I will concentrate on the broad band spectrum, the timing signatures and the energy budget of these objects. In particular I will stress the similarities and differences in the x-ray spectra and power density spectra of AGN, ultraluminous x-ray sources and galactic black holes as a function of 'state'. I will also discuss the nature of the Fe K line and other diagnostics of the regions near the event horizon.

  20. Modified viscosity in accretion disks. Application to Galactic black hole binaries, intermediate mass black holes and AGN

    CERN Document Server

    Grzędzielski, Mikołaj; Czerny, Bożena; Wu, Qingwen

    2016-01-01

    Black holes surrounded by accretion disks are present in the Universe in different scales of masses, from microquasars up to the Active Galactic Nuclei. The current picture of the accretion disk theory remains still ad hoc, due the complexity of the magnetic field action. In addition, the accretion disks at high Eddington rates can be radiation-pressure dominated and, according to some of the heating prescriptions, thermally unstable. The observational verification of their resulting variability patterns may shed the light on both the role of radiation pressure and magnetic field in the accretion process. We compute the structure and time evolution of an accretion disk. We supplement this model with a modified viscosity prescription, which can to some extent describe the magnetization of the disk. We study the results for a large grid of models and derive conclusions separately for different scales of black hole masses. We show the dependences between the flare, or outburst, duration, its amplitude and period...

  1. Black holes

    CERN Document Server

    Chrúsciel, P T

    2002-01-01

    This paper is concerned with several not-quantum aspects of black holes, with emphasis on theoretical and mathematical issues related to numerical modeling of black hole space-times. Part of the material has a review character, but some new results or proposals are also presented. We review the experimental evidence for existence of black holes. We propose a definition of black hole region for any theory governed by a symmetric hyperbolic system of equations. Our definition reproduces the usual one for gravity, and leads to the one associated with the Unruh metric in the case of Euler equations. We review the global conditions which have been used in the Scri-based definition of a black hole and point out the deficiencies of the Scri approach. Various results on the structure of horizons and apparent horizons are presented, and a new proof of semi-convexity of horizons based on a variational principle is given. Recent results on the classification of stationary singularity-free vacuum solutions are reviewed. ...

  2. Extreme mass ratio inspiral rates: dependence on the massive black hole mass

    CERN Document Server

    Hopman, Clovis

    2009-01-01

    We study the rate at which stars spiral into a massive black hole (MBH) due to the emission of gravitational waves (GWs), as a function of the mass M of the MBH. In the context of our model, it is shown analytically that the rate approximately depends on the MBH mass as M^{-1/4}. Numerical simulations confirm this result, and show that for all MBH masses, the event rate is highest for stellar black holes, followed by white dwarfs, and lowest for neutron stars. The Laser Interferometer Space Antenna (LISA) is expected to see hundreds of these extreme mass ratio inspirals per year. Since the event rate derived here formally diverges as M->0, the model presented here cannot hold for MBHs of masses that are too low, and we discuss what the limitations of the model are.

  3. Observational Constraints on Quasar Black Hole Mass Distributions, Eddington Ratio Distributions, and Lifetimes

    DEFF Research Database (Denmark)

    Kelly, Brandon C.; Vestergaard, Marianne; Fan, X.

    2010-01-01

    I will present the black hole mass function (BHMF) of broad line quasars in the SDSS DR3. We employ a powerful Bayesian statistical technique that corrects for incompleteness and the statistical uncertainty in the mass estimates. We find evidence that the most massive black hole appeared as quasars...... earlier in the universe, and that most quasars are not radiating at or near the Eddington limit. I will also present constraints on the quasar lifetime and maximum black hole mass, derived from the mass functions....

  4. Exploring radio and jet properties across the black hole mass scale

    NARCIS (Netherlands)

    van Oers, P.C.N.

    2016-01-01

    Some black holes are bright in radio while others are not. In this thesis we explore why, relating the radio emission to the relativistic jet phenomenon and examining how the emission behaves across the entire observed, 8 magnitude wide black hole mass scale. First we model detailed broadband spectr

  5. The fundamental plane of accretion onto black holes with dynamical masses

    NARCIS (Netherlands)

    K. Gültekin; E.M. Cackett; J.M. Miller; T. Di Matteo; S. Markoff; D.O. Richstone

    2009-01-01

    Black hole accretion and jet production are areas of intensive study in astrophysics. Recent work has found a relation between radio luminosity, X-ray luminosity, and black hole mass. With the assumption that radio and X-ray luminosities are suitable proxies for jet power and accretion power, respec

  6. QCD against BlackHoles of Stellar Mass

    CERN Document Server

    Royzen, Ilya I

    2012-01-01

    In course of the consolidation of nucleon (neutron) spacing inside a compact star, two key factors are expected to come into play side by side: the lack of self-stabilization against shutting into black hole (BH) and forthcoming phase transition - color deconfinement and QCD-vacuum reconstruction - within the nuclear matter the star is composed of. These phenomena bring the star to evolve in the quite different (opposite) ways and should be taken into account at once, as the gravitational compression is considered. Under the above transition, which is expected to occur within any supermassive neutron star (NS), the hadronic-phase (HPh) vacuum - a coherent state of gluon- and chiral $q\\bar q$-condensates - turns, first near the star center, into the "empty" (perturbation) subhadronic-phase (SHPh) one and, thus, pre-existing (very high) vacuum pressure falls there down rather abruptly; as a result, the "cold" star starts collapsing almost freely into the new vacuum. If the stellar mass is sufficiently large, th...

  7. Calculating the mass spectrum of primordial black holes

    CERN Document Server

    Young, Sam; Sasaki, Misao

    2014-01-01

    We reinspect the calculation for the mass fraction of primordial black holes (PBHs) which are formed from primordial perturbations, finding that performing the calculation using the comoving curvature perturbation $\\mathcal{R}_{c}$ in the standard way vastly overestimates the number of PBHs, by many orders of magnitude. This is because PBHs form shortly after horizon entry, meaning modes significantly larger than the PBH are unobservable and should not affect whether a PBH forms or not - this important effect is not taken into account by smoothing the distribution in the standard fashion. We discuss alternative methods and argue that the density contrast, $\\Delta$, should be used instead as super-horizon modes are damped by a factor $k^{2}$. We make a comparison between using a Press-Schechter approach and peaks theory, finding that the two are in close agreement in the region of interest. We also investigate the effect of varying the spectral index, and the running of the spectral index, on the abundance of ...

  8. A new mass scale, implications on black hole evaporation and holography

    CERN Document Server

    Burikham, Piyabut; Wuthicharn, Taum

    2016-01-01

    We consider a new mass scale $M_{T}=(\\hbar^{2}\\sqrt{\\Lambda}/G)^{1/3}$ constructed from dimensional analysis by using $G$, $\\hbar$ and $\\Lambda$ and discuss its physical interpretation. Based on the Generalized Uncertainty Relation, a black hole with age comparable to the universe would stop radiating when the mass reaches a new mass scale $M'_{T}=c(\\hbar/G^{2}\\sqrt{\\Lambda})^{1/3}$ at which its temperature corresponds to the mass $M_{T}$. Black hole remnants could have masses ranging from a Planck mass to a trillion kilograms. Holography persists even when the uncertainty relation is modified to the Minimum Length Uncertainty Relation~(MLUR). The remnant black hole entropy is proportional to the surface area of the black hole in unit of the Planck area in arbitrary noncompact dimensions.

  9. A black-hole mass measurement from molecular gas kinematics in NGC4526.

    Science.gov (United States)

    Davis, Timothy A; Bureau, Martin; Cappellari, Michele; Sarzi, Marc; Blitz, Leo

    2013-02-21

    The masses of the supermassive black holes found in galaxy bulges are correlated with a multitude of galaxy properties, leading to suggestions that galaxies and black holes may evolve together. The number of reliably measured black-hole masses is small, and the number of methods for measuring them is limited, holding back attempts to understand this co-evolution. Directly measuring black-hole masses is currently possible with stellar kinematics (in early-type galaxies), ionized-gas kinematics (in some spiral and early-type galaxies) and in rare objects that have central maser emission. Here we report that by modelling the effect of a black hole on the kinematics of molecular gas it is possible to fit interferometric observations of CO emission and thereby accurately estimate black-hole masses. We study the dynamics of the gas in the early-type galaxy NGC 4526, and obtain a best fit that requires the presence of a central dark object of 4.5(+4.2)(-3.1) × 10(8) solar masses (3σ confidence limit). With the next-generation millimetre-wavelength interferometers these observations could be reproduced in galaxies out to 75 megaparsecs in less than 5 hours of observing time. The use of molecular gas as a kinematic tracer should thus allow one to estimate black-hole masses in hundreds of galaxies in the local Universe, many more than are accessible with current techniques.

  10. Asymptotic Black Holes

    CERN Document Server

    Ho, Pei-Ming

    2016-01-01

    Following earlier works on the KMY model of black-hole formation and evaporation, we construct the metric for a matter sphere in gravitational collapse, with the back-reaction of pre-Hawking radiation taken into consideration. The mass distribution and collapsing velocity of the matter sphere are allowed to have an arbitrary radial dependence. We find that a generic gravitational collapse asymptote to a universal configuration which resembles a black hole but without horizon. This approach clarifies several misunderstandings about black-hole formation and evaporation, and provides a new model for black-hole-like objects in the universe.

  11. Asymptotic black holes

    Science.gov (United States)

    Ho, Pei-Ming

    2017-04-01

    Following earlier works on the KMY model of black-hole formation and evaporation, we construct the metric for a matter sphere in gravitational collapse, with the back-reaction of pre-Hawking radiation taken into consideration. The mass distribution and collapsing velocity of the matter sphere are allowed to have an arbitrary radial dependence. We find that a generic gravitational collapse asymptote to a universal configuration which resembles a black hole but without horizon. This approach clarifies several misunderstandings about black-hole formation and evaporation, and provides a new model for black-hole-like objects in the universe.

  12. Pulsar timing can constrain primordial black holes in the LIGO mass window

    CERN Document Server

    Schutz, Katelin

    2016-01-01

    The recent discovery of gravitational waves from merging black holes has generated interest in primordial black holes as a possible component of the dark matter. In this paper, we show that pulsar timing may soon have sufficient data to constrain $1$-$1000\\,M_{\\odot}$ primordial black holes via the non-detection of a third-order Shapiro time delay as the black holes move around the Galactic halo. We present the results of a Monte Carlo simulation which suggests that future data from known pulsars may be capable of constraining the PBH density more stringently than other existing methods in the mass range ~1-30$\\,M_{\\odot}$. We find that timing new pulsars discovered using the proposed Square Kilometre Array may constrain primordial black holes in this mass range to comprise less than ~1-10% of the dark matter.

  13. Pulsar timing can constrain primordial black holes in the LIGO mass window

    Science.gov (United States)

    Schutz, Katelin; Liu, Adrian

    2017-01-01

    The recent discovery of gravitational waves from merging black holes has generated interest in primordial black holes as a possible component of dark matter. In this paper, we show that pulsar timing may soon have sufficient data to constrain 1 - 1000 M⊙ primordial black holes (PBHs) via the nondetection of a third-order Shapiro time delay as the black holes move around the Galactic halo. We present the results of a Monte Carlo simulation which suggests that future data from known pulsars may be capable of constraining the PBH density more stringently than other existing methods in the mass range ˜1 - 30 M⊙ . We find that timing new pulsars discovered using the proposed Square Kilometre Array may constrain primordial black holes in this mass range to comprise less than ˜1 %- 10 % of the dark matter.

  14. THE CLOSE STELLAR COMPANIONS TO INTERMEDIATE-MASS BLACK HOLES

    Energy Technology Data Exchange (ETDEWEB)

    MacLeod, Morgan; Ramirez-Ruiz, Enrico [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Trenti, Michele [School of Physics, The University of Melbourne, VIC 3010 (Australia)

    2016-03-01

    When embedded in dense cluster cores, intermediate-mass black holes (IMBHs) acquire close stellar or stellar-remnant companions. These companions are not only gravitationally bound, but also tend to hierarchically isolate from other cluster stars through series of multibody encounters. In this paper we study the demographics of IMBH companions in compact star clusters through direct N-body simulations. We study clusters initially composed of 10{sup 5} or 2 × 10{sup 5} stars with IMBHs of 75 and 150 solar masses, and we follow their evolution for 6–10 Gyr. A tight, innermost binary pair of IMBH and stellar object rapidly forms. The IMBH has a companion with an orbital semimajor axis at least three times tighter than the second-most-bound object over 90% of the time. These companionships have typical periods on the order of years and are subject to cycles of exchange and destruction. The most frequently observed, long-lived pairings persist for ∼10{sup 7} years. The demographics of IMBH companions in clusters are diverse: they include both main-sequence, giant stars and stellar remnants. Companion objects may reveal the presence of an IMBH in a cluster in one of several ways. The most-bound companion stars routinely suffer grazing tidal interactions with the IMBH, offering a dynamical mechanism to produce repeated flaring episodes like those seen in the IMBH candidate HLX-1. The stellar winds of companion stars provide a minimum quiescent accretion rate for IMBHs, with implications for radio searches for IMBH accretion in globular clusters. Finally, gravitational wave inspirals of compact objects occur with promising frequency.

  15. Testing a scale-independent method to measure the mass of black holes

    CERN Document Server

    Gliozzi, M; Satyapal, S; Price, D M; Jang, I

    2011-01-01

    Estimating the black hole mass at the center of galaxies is a fundamental step not only for understanding the physics of accretion, but also for the cosmological evolution of galaxies. Recently a new method, based solely on X-ray data, was successfully applied to determine the black hole mass in Galactic systems. Since X-rays are thought to be produced via Comptonization process both in stellar and supermassive black holes, in principle, the same method may be applied to estimate the mass in supermassive black holes. In this work we test this hypothesis by performing a systematic analysis of a sample of AGNs, whose black hole mass has been already determined via reverberation mapping and which possess high quality XMM-Newton archival data. The good agreement obtained between the black hole masses derived with this novel scaling technique and the reverberation mapping values suggests that this method is robust and works equally well on stellar and supermassive black holes, making it a truly scale-independent t...

  16. Establishing a relation between the mass and the spin of stellar-mass black holes.

    Science.gov (United States)

    Banerjee, Indrani; Mukhopadhyay, Banibrata

    2013-08-09

    Stellar mass black holes (SMBHs), forming by the core collapse of very massive, rapidly rotating stars, are expected to exhibit a high density accretion disk around them developed from the spinning mantle of the collapsing star. A wide class of such disks, due to their high density and temperature, are effective emitters of neutrinos and hence called neutrino cooled disks. Tracking the physics relating the observed (neutrino) luminosity to the mass, spin of black holes (BHs) and the accretion rate (M) of such disks, here we establish a correlation between the spin and mass of SMBHs at their formation stage. Our work shows that spinning BHs are more massive than nonspinning BHs for a given M. However, slowly spinning BHs can turn out to be more massive than spinning BHs if M at their formation stage was higher compared to faster spinning BHs.

  17. A 17-billion-solar-mass black hole in a group galaxy with a diffuse core.

    Science.gov (United States)

    Thomas, Jens; Ma, Chung-Pei; McConnell, Nicholas J; Greene, Jenny E; Blakeslee, John P; Janish, Ryan

    2016-04-21

    Quasars are associated with and powered by the accretion of material onto massive black holes; the detection of highly luminous quasars with redshifts greater than z = 6 suggests that black holes of up to ten billion solar masses already existed 13 billion years ago. Two possible present-day 'dormant' descendants of this population of 'active' black holes have been found in the galaxies NGC 3842 and NGC 4889 at the centres of the Leo and Coma galaxy clusters, which together form the central region of the Great Wall--the largest local structure of galaxies. The most luminous quasars, however, are not confined to such high-density regions of the early Universe; yet dormant black holes of this high mass have not yet been found outside of modern-day rich clusters. Here we report observations of the stellar velocity distribution in the galaxy NGC 1600--a relatively isolated elliptical galaxy near the centre of a galaxy group at a distance of 64 megaparsecs from Earth. We use orbit superposition models to determine that the black hole at the centre of NGC 1600 has a mass of 17 billion solar masses. The spatial distribution of stars near the centre of NGC 1600 is rather diffuse. We find that the region of depleted stellar density in the cores of massive elliptical galaxies extends over the same radius as the gravitational sphere of influence of the central black holes, and interpret this as the dynamical imprint of the black holes.

  18. Black Holes in Our Universe: Do They Inch Up the Mass Ladder?

    Indian Academy of Sciences (India)

    Prajval Shastri

    2017-03-01

    Current technologies have enabled glimpses at the many facetsof black holes, which we know to be plentiful in our cosmos.A panoramic view of the evidence for them is presented hereacross the large range of masses that they span.

  19. How Much Mass do Supermassive Black Holes Eat in their Old Age?

    CERN Document Server

    Hopkins, P F; Hernquist, L; Hopkins, Philip F.; Narayan, Ramesh; Hernquist, Lars

    2005-01-01

    We consider the distribution of local supermassive black hole Eddington ratios and accretion rates, accounting for the dependence of radiative efficiency and bolometric corrections on the accretion rate. We find that black hole mass growth, both of the integrated mass density and the masses of most individual objects, must be dominated by an earlier, radiatively efficient, high accretion rate stage, and not by the radiatively inefficient low accretion rate phase in which most local supermassive black holes are currently observed. This conclusion is particularly true of supermassive black holes in elliptical host galaxies, as expected if they have undergone merger activity in the past which would fuel quasar activity and rapid growth. We discuss models of the time evolution of accretion rates and show that they all predict significant mass growth in a prior radiatively efficient state. The only way to avoid this conclusion is through careful fine-tuning of the accretion/quasar timescale to a value that is inco...

  20. Do floating orbits in extreme mass ratio binary black holes exist?

    CERN Document Server

    Kapadia, Shasvath J; Glampedakis, Kostas

    2013-01-01

    This paper examines the possibility of floating or non-decaying orbits for extreme mass ratio binary black holes. In the adiabatic approximation, valid in the extreme mass ratio case, if the orbital flux lost due to gravitational radiation reaction is compensated for by the orbital flux gained from the spins of the black holes via superradiant scattering (or, equivalently, tidal acceleration) the orbital decay would be stalled, causing the binary to "float". We show that this flux balance is not, in practice, possible for extreme mass ratio binary black holes with circular equatorial orbits; furthermore, adding eccentricity and inclination to the orbits will not significantly change this null result, thus ruling out the possibility of floating orbits for extreme mass ratio binary black holes. We also argue that binaries consisting of material bodies dense and massive enough to generate gravitational waves detectable by any kind of gravitational wave detector are also unlikely to float. Using a multipolar anal...

  1. The mass of the black hole in LMC X-3

    Energy Technology Data Exchange (ETDEWEB)

    Orosz, Jerome A. [Department of Astronomy, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182-1221 (United States); Steiner, James F.; McClintock, Jeffrey E. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Buxton, Michelle M.; Bailyn, Charles D. [Department of Astronomy, Yale University, P.O. Box 208101, New Haven, CT 06520-8101 (United States); Steeghs, Danny [Department of Physics, University of Warwick, Coventry, CV4 7AL, UK and Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Guberman, Alec [Byram Hills High School, 12 Tripp Lane, Armonk, NY 10504 (United States); Torres, Manuel A. P., E-mail: jorosz@mail.sdsu.edu, E-mail: jsteiner@cfa.harvard.edu, E-mail: jem@cfa.harvard.edu, E-mail: michelle.buxton@yale.edu, E-mail: charles.bailyn@yale.edu, E-mail: D.T.H.Steeghs@warwick.ac.uk, E-mail: alec.guberman@stonybrook.edu, E-mail: M.Torres@sron.nl [SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht (Netherlands)

    2014-10-20

    We analyze a large set of new and archival photometric and spectroscopic observations of LMC X-3 to arrive at a self-consistent dynamical model for the system. Using echelle spectra obtained with the Magellan Inamori Kyocera Echelle instrument on the 6.5 m Magellan Clay telescope and the UVES instrument on the second 8.2 m Very Large Telescope, we find a velocity semiamplitude for the secondary star of K {sub 2} = 241.1 ± 6.2 km s{sup –1}, where the uncertainty includes an estimate of the systematic error caused by X-ray heating. Using the spectra, we also find a projected rotational velocity of V {sub rot}sin i = 118.5 ± 6.6 km s{sup –1}. From an analysis of archival B and V light curves as well as new B and V light curves from the SMARTS 1.3 m telescope, we find an inclination of i = 69.°84 ± 0.°37 for models that do not include X-ray heating and an inclination of i = 69.°24 ± 0.°72 for models that incorporate X-ray heating. Adopting the latter inclination measurement, we find masses of 3.63 ± 0.57 M {sub ☉} and 6.98 ± 0.56 M {sub ☉} for the companion star and the black hole, respectively. We briefly compare our results with earlier work and discuss some of their implications.

  2. Improved Dynamical Constraints on the Mass of the Central Black Hole in NGC 404

    Science.gov (United States)

    Nguyen, Dieu D.; Seth, Anil C.; den Brok, Mark; Neumayer, Nadine; Cappellari, Michele; Barth, Aaron J.; Caldwell, Nelson; Williams, Benjamin F.; Binder, Breanna

    2017-02-01

    We explore the nucleus of the nearby 109 {M}ȯ early-type galaxy, NGC 404, using Hubble Space Telescope (HST)/STIS spectroscopy and WFC3 imaging. We first present evidence for nuclear variability in UV, optical, and infrared filters over a time period of 15 years. This variability adds to the already substantial evidence for an accreting black hole at the center of NGC 404. We then redetermine the dynamical black hole mass in NGC 404 including modeling of the nuclear stellar populations. We combine HST/STIS spectroscopy with WFC3 images to create a local color–M/L relation derived from stellar population modeling of the STIS data. We then use this to create a mass model for the nuclear region. We use Jeans modeling to fit this mass model to adaptive optics stellar kinematic observations from Gemini/NIFS. From our stellar dynamical modeling, we find a 3σ upper limit on the black hole mass of 1.5× {10}5 {M}ȯ . Given the accretion evidence for a black hole, this upper limit makes NGC 404 the lowest mass central black hole with dynamical mass constraints. We find that the kinematics of H2 emission line gas show evidence for non-gravitational motions preventing the use of gas dynamical modeling to constrain the black hole mass. Our stellar population modeling also reveals that the central, counter-rotating region of the nuclear cluster is dominated by ∼1 Gyr old populations.

  3. Numerical Relativity in D dimensional space-times: Collisions of unequal mass black holes

    Energy Technology Data Exchange (ETDEWEB)

    Witek, Helvi; Cardoso, Vitor; Sperhake, Ulrich [CENTRA, Departamento de Fisica, Instituto Superior Tecnico, Universidade Tecnica de Lisboa - UTL, Av. Rovisco Pais 1, 1049 Lisboa (Portugal); Gualtieri, Leonardo [Dipartimento di Fisica, Universita di Roma ' Sapienza' and Sezione INFN Roma1, P.A. Moro 5, 00185, Roma (Italy); Herdeiro, Carlos [Departamento de Fisica da Universidade de Aveiro, Campus de Santiago, 3810-183 Aveiro (Portugal); Zilhao, Miguel, E-mail: helvi.witek@ist.utl.pt [Centro de Fisica do Porto - CFP, Departamento de Fisica e Astronomia, Faculdade de Ciencias da Universidade do Porto - FCUP, Rua do Campo Alegre, 4169-007 Porto (Portugal)

    2011-09-22

    We present unequal mass head-on collisions of black holes in D = 5 dimensional space-times. We have simulated BH systems with mass ratios q 1,1/2, 1/3, 1/4. We extract the total energy radiated throughout the collision and compute the linear momentum flux and the recoil velocity of the final black hole. The numerical results show very good agreement with point particle calculations when extrapolated to this limit.

  4. Eddington-limited accretion and the black hole mass function at redshift 6

    CERN Document Server

    Willott, Chris J; Arzoumanian, Doris; Bergeron, Jacqueline; Crampton, David; Delorme, Philippe; Hutchings, John B; Omont, Alain; Reyle, Celine; Schade, David

    2010-01-01

    We present discovery observations of a quasar in the Canada-France High-z Quasar Survey (CFHQS) at redshift z=6.44. We also use near-IR spectroscopy of nine CFHQS quasars at z~6 to determine black hole masses. These are compared with similar estimates for more luminous Sloan Digital Sky Survey (SDSS) quasars to investigate the relationship between black hole mass and quasar luminosity. We find a strong correlation between MgII FWHM and UV luminosity and that most quasars at this early epoch are accreting close to the Eddington limit. Thus these quasars appear to be in an early stage of their life cycle where they are building up their black hole mass exponentially. Combining these results with the quasar luminosity function, we derive the black hole mass function at z=6. Our black hole mass function is ~10^4 times lower than at z=0 and substantially below estimates from previous studies. The main uncertainties which could increase the black hole mass function are a larger population of obscured quasars at hig...

  5. A Global Spectral Study of Stellar-Mass Black Holes with Unprecedented Sensitivity

    Science.gov (United States)

    Garci, Javier

    There are two well established populations of black holes: (i) stellar-mass black holes with masses in the range 5 to 30 solar masses, many millions of which are present in each galaxy in the universe, and (ii) supermassive black holes with masses in the range millions to billions of solar masses, which reside in the nucleus of most galaxies. Supermassive black holes play a leading role in shaping galaxies and are central to cosmology. However, they are hard to study because they are dim and they scarcely vary on a human timescale. Luckily, their variability and full range of behavior can be very effectively studied by observing their stellar-mass cousins, which display in miniature the full repertoire of a black hole over the course of a single year. The archive of data collected by NASA's Rossi X-ray Timing Explorer (RXTE) during its 16 year mission is of first importance for the study of stellar-mass black holes. While our ultimate goal is a complete spectral analysis of all the stellar-mass black hole data in the RXTE archive, the goal of this proposal is the global study of six of these black holes. The two key methodologies we bring to the study are: (1) Our recently developed calibration tool that increases the sensitivity of RXTE's detector by up to an order of magnitude; and (2) the leading X-ray spectral "reflection" models that are arguably the most effective means currently available for probing the effects of strong gravity near the event horizon of a black hole. For each of the six black holes, we will fit our models to all the archived spectral data and determine several key parameters describing the black hole and the 10-million-degree gas that surrounds it. Of special interest will be our measurement of the spin (or rate of rotation) of each black hole, which can be as high as tens of thousands of RPM. Profoundly, all the properties of an astronomical black hole are completely defined by specifying its spin and its mass. The main goal of this

  6. Quiescence correlates strongly with directly-measured black hole mass in central galaxies

    CERN Document Server

    Terrazas, Bryan A; Henriques, Bruno M B; White, Simon D M; Cattaneo, Andrea; Woo, Joanna

    2016-01-01

    Roughly half of all stars reside in galaxies without significant ongoing star formation. However, galaxy formation models indicate that it is energetically challenging to suppress the cooling of gas and the formation of stars in galaxies that lie at the centers of their dark matter halos. In this Letter, we show that the dependence of quiescence on black hole and stellar mass is a powerful discriminant between differing models for the mechanisms that suppress star formation. Using observations of 91 star-forming and quiescent central galaxies with directly-measured black hole masses, we find that quiescent galaxies host more massive black holes than star-forming galaxies with similar stellar masses. This observational result is in qualitative agreement with models that assume that effective, more-or-less continuous AGN feedback suppresses star formation, strongly suggesting the importance of the black hole in producing quiescence in central galaxies.

  7. Quiescence Correlates Strongly with Directly Measured Black Hole Mass in Central Galaxies

    Science.gov (United States)

    Terrazas, Bryan A.; Bell, Eric F.; Henriques, Bruno M. B.; White, Simon D. M.; Cattaneo, Andrea; Woo, Joanna

    2016-10-01

    Roughly half of all stars reside in galaxies without significant ongoing star formation. However, galaxy formation models indicate that it is energetically challenging to suppress the cooling of gas and the formation of stars in galaxies that lie at the centers of their dark matter halos. In this Letter, we show that the dependence of quiescence on black hole and stellar mass is a powerful discriminant between differing models for the mechanisms that suppress star formation. Using observations of 91 star-forming and quiescent central galaxies with directly measured black hole masses, we find that quiescent galaxies host more massive black holes than star-forming galaxies with similar stellar masses. This observational result is in qualitative agreement with models that assume that effective, more-or-less continuous active galactic nucleus feedback suppresses star formation, strongly suggesting the importance of the black hole in producing quiescence in central galaxies.

  8. Growth of Primordial Black Holes

    Science.gov (United States)

    Harada, Tomohiro

    Primordial black holes have important observational implications through Hawking evaporation and gravitational radiation as well as being a candidate for cold dark matter. Those black holes are assumed to have formed in the early universe typically with the mass scale contained within the Hubble horizon at the formation epoch and subsequently accreted mass surrounding them. Numerical relativity simulation shows that primordial black holes of different masses do not accrete much, which contrasts with a simplistic Newtonian argument. We see that primordial black holes larger than the 'super-horizon' primordial black holes have decreasing energy and worm-hole like struture, suggesting the formation through quamtum processes.

  9. Constraining the formation of black-holes in short-period Black-Hole Low-Mass X-ray Binaries

    CERN Document Server

    Repetto, Serena

    2015-01-01

    The formation of stellar mass black holes is still very uncertain. Two main uncertainties are the amount of mass ejected in the supernova event (if any) and the magnitude of the natal kick the black hole receives at birth (if any). Repetto et al. (2012), studying the position of Galactic X-ray binaries containing black holes, found evidence for black holes receiving high natal kicks at birth. In this Paper we extend that study, taking into account the previous binary evolution of the sources as well. The seven short-period black-hole X-ray binaries that we use, are compact binaries consisting of a low-mass star orbiting a black hole in a period less than $1$ day. We trace their binary evolution backwards in time, from the current observed state of mass-transfer, to the moment the black hole was formed, and we add the extra information on the kinematics of the binaries. We find that several systems could be explained by no natal kick, just mass ejection, while for two systems (and possibly more) a high kick is...

  10. Constraining black hole masses in low-accreting AGN using X-ray spectra

    CERN Document Server

    Jang, I; Hughes, C; Titarchuk, L

    2014-01-01

    In a recent work we demonstrated that a novel X-ray scaling method, originally introduced for Galactic black holes (GBHs), can be reliably extended to estimate the mass of supermassive black holes accreting at a moderate to high level. Here we investigate the limits of applicability of this method to low-accreting active galactic nuclei, using a control sample with good-quality X-ray data and dynamically measured mass. For low-accreting AGNs, because the basic assumption that the photon index positively correlates with the accretion rate no longer holds the X-ray scaling method cannot be used. Nevertheless, the inverse correlation in the Gamma-Lx/LEdd diagram, found in several low-accreting black holes and confirmed by this sample, can be used to constrain black hole mass within a factor of ~10 from the dynamically determined values. We provide a simple recipe to determine black hole mass using solely X-ray spectral data, which can be used as a sanity check for black hole mass determination based on indirect ...

  11. The characteristic black hole mass resulting from direct collapse in the early Universe

    Science.gov (United States)

    Latif, M. A.; Schleicher, D. R. G.; Schmidt, W.; Niemeyer, J. C.

    2013-12-01

    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 haloes with Tvir ≥ 104 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 20 000 yr 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 105 M⊙ are formed in the presence of strong Lyman-Werner flux which leads to an isothermal collapse. The characteristic mass is about two times higher in LES compared to the implicit large eddy simulations. The accretion rates increase with time and reach a maximum value of 10 M⊙ yr-1 after 104 yr. Our results show that the direct collapse model is clearly feasible as it provides the expected mass of the seed black holes.

  12. A 400-solar-mass black hole in the galaxy M82.

    Science.gov (United States)

    Pasham, Dheeraj R; Strohmayer, Tod E; Mushotzky, Richard F

    2014-09-04

    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 of 3.32 ± 0.06 hertz and 5.07 ± 0.06 hertz. Assuming that we can extrapolate the inverse-mass scaling that holds for stellar-mass black holes, we estimate the black hole mass of M82 X-1 to be 428 ± 105 solar masses. In addition, we can estimate the mass using the relativistic precession model, from which we get a value of 415 ± 63 solar masses.

  13. Prospects for measuring supermassive black hole masses with future extremely large telescopes

    Energy Technology Data Exchange (ETDEWEB)

    Do, Tuan; Wright, Shelley A. [Dunlap Institute for Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto M5S 3H4, ON (Canada); Barth, Aaron J.; Barton, Elizabeth J. [Department of Physics and Astronomy, 4129 Frederick Reines Hall, University of California, Irvine, CA 92697-4575 (United States); Simard, Luc [Herzberg Institute of Astrophysics, National Research Council of Canada, Victoria, BC, V9E 2E7 (Canada); Larkin, James E. [Physics and Astronomy Department, University of California, Los Angeles, CA 90095-1547 (United States); Moore, Anna M. [Caltech Optical Observatories, California Institute of Technology, Pasadena, CA (United States); Wang, Lianqi; Ellerbroek, Brent [TMT Observatory Corporation Instrumentation Department, Pasadena, CA (United States)

    2014-04-01

    The next generation of giant-segmented mirror telescopes (>20 m) will enable us to observe galactic nuclei at much higher angular resolution and sensitivity than ever before. These capabilities will introduce a revolutionary shift in our understanding of the origin and evolution of supermassive black holes by enabling more precise black hole mass measurements in a mass range that is unreachable today. We present simulations and predictions of the observations of nuclei that will be made with the Thirty Meter Telescope (TMT) and the adaptive optics assisted integral-field spectrograph IRIS, which is capable of diffraction-limited spectroscopy from Z band (0.9 μm) to K band (2.2 μm). These simulations, for the first time, use realistic values for the sky, telescope, adaptive optics system, and instrument to determine the expected signal-to-noise ratio of a range of possible targets spanning intermediate mass black holes of ∼10{sup 4} M {sub ☉} to the most massive black holes known today of >10{sup 10} M {sub ☉}. We find that IRIS will be able to observe Milky Way mass black holes out the distance of the Virgo Cluster, and will allow us to observe many more of the brightest cluster galaxies where the most massive black holes are thought to reside. We also evaluate how well the kinematic moments of the velocity distributions can be constrained at the different spectral resolutions and plate scales designed for IRIS. We find that a spectral resolution of ∼8000 will be necessary to measure the masses of intermediate mass black holes. By simulating the observations of galaxies found in Sloan Digital Sky Survey DR7, we find that over 10{sup 5} massive black holes will be observable at distances between 0.005 < z < 0.18 with the estimated sensitivity and angular resolution provided by access to Z-band (0.9 μm) spectroscopy from IRIS and the TMT adaptive optics system. These observations will provide the most accurate dynamical measurements of black hole masses to

  14. Primordial Black Hole Baryogenesis

    CERN Document Server

    Baumann, D; Turok, N G; Baumann, Daniel; Steinhardt, Paul J.; Turok, Neil

    2007-01-01

    We reconsider the possibility that the observed baryon asymmetry was generated by the evaporation of primordial black holes that dominated the early universe. We present a simple derivation showing that the baryon asymmetry is insensitive to the initial black hole density and the cosmological model but is sensitive to the temperature-dependence of the CP and baryon-violating (or lepton-violating) interactions. We also consider the possibility that black holes stop evaporating and form Planck-mass remnants that act as dark matter. We show that primordial black holes cannot simultaneously account for both the observed baryon asymmetry and the (remnant) dark matter density unless the magnitude of CP violation is much greater than expected from most particle physics models. Finally, we apply these results to ekpyrotic/cyclic models, in which primordial black holes may form when branes collide. We find that obtaining the observed baryon asymmetry is compatible with the other known constraints on parameters.

  15. Three probable stellar-mass black holes. Master's thesis

    Energy Technology Data Exchange (ETDEWEB)

    Fry, D.W.

    1988-01-01

    According to the theory of general relativity, a spherically symmetric self-gravitating body whose radius/mass ratio in Schwarzchild coordinates decreases to the critical value of 2 must collapse to a point singularity. Such an object is termed a black hole, since out to a characteristic radius known as the event horizon, not even photons can escape its strong gravitational field. It has been postulated that such a field could serve to compress and heat accreting gas, which would then emit soft x rays, signalling the black hole's presence. One accretion model is that of a black hole in binary orbit with a normal luminous star which is ejecting part of its mass, some of which is captured by the companion black hole and emits x rays before disappearing inside the event horizon. Objects consisting of degenerate nuclear matter known as neutron stars, and whose existence has been well established, could also serve as the x ray companion in such a system. One way to distinguish between a neutron star and a black hole is to measure their mass, for if casualty is to be preserved, a neutron star cannot exceed about 3 solar masses, while the mass of a black hole is arbitrary. A lower limit on the mass of the x-ray emitter in a binary system can be determined if the orbital period, projected orbital velocity, and mass or radius of the luminous companion star can be measured via conventional astronomical methods. Presently, three binary systems so appear to contain an x-ray emitter whose mass exceeds 3 solar masses and must likely be a black hole. They are Cygnus X-1, LMC X-3, and A0620-00.

  16. Perturbative effects of spinning black holes in the extreme mass-ratio limit

    Energy Technology Data Exchange (ETDEWEB)

    Nakano, Hiroyuki; Campanelli, Manuela; Lousto, Carlos O; Zlochower, Yosef, E-mail: nakano@astro.rit.edu, E-mail: manuela@astro.rit.edu, E-mail: lousto@astro.rit.edu, E-mail: yosef@astro.rit.edu [Center for Computational Relativity and Gravitation, School of Mathematical Sciences, Rochester Institute of Technology, Rochester, NY 14623 (United States)

    2011-07-07

    Recently, we proposed an enhancement of the Regge-Wheeler-Zerilli formalism for first-order perturbations about a Schwarzschild background that includes first-order corrections due to the background black-hole spin in the black-hole perturbation approach. Using this formalism, we analytically investigate gravitational wave emission and linear momentum flux from a head-on collision of two spinning black holes in the extreme mass-ratio limit. The result derived in the lowest slow-motion and weak-field approximations here is consistent with the post-Newtonian calculation.

  17. Effect of scalar field mass on gravitating charged scalar solitons and black holes in a cavity

    CERN Document Server

    Ponglertsakul, Supakchai

    2016-01-01

    We study soliton and black hole solutions of Einstein charged scalar field theory in cavity. We examine the effect of introducing a scalar field mass on static, spherically symmetric solutions of the field equations. We focus particularly on the spaces of soliton and black hole solutions, as well as studying their stability under linear, spherically symmetric perturbations of the metric, electromagnetic field, and scalar field.

  18. Massive particles' tunnelling radiation from the black hole with a mass-quadruple moment

    Institute of Scientific and Technical Information of China (English)

    Han Yi-Wen

    2007-01-01

    In this paper, we extend Zhang and Zhao's recent work to the black hole with a mass-quadruple moment. The behaviour of the tunnelling massive particles is investigated, and the emission rate at which massive particles tunnel across the event horizon of the black hole is calculated. The result is consistent with an underlying unitary theory, and takes the same functional form as that of a massless particle.

  19. Effect of scalar field mass on gravitating charged scalar solitons and black holes in a cavity

    Science.gov (United States)

    Ponglertsakul, Supakchai; Winstanley, Elizabeth

    2017-01-01

    We study soliton and black hole solutions of Einstein charged scalar field theory in cavity. We examine the effect of introducing a scalar field mass on static, spherically symmetric solutions of the field equations. We focus particularly on the spaces of soliton and black hole solutions, as well as studying their stability under linear, spherically symmetric perturbations of the metric, electromagnetic field, and scalar field.

  20. A Black Hole Mass Determination for the Compact Galaxy Mrk 1216

    Science.gov (United States)

    Walsh, Jonelle L.; van den Bosch, Remco C. E.; Gebhardt, Karl; Yıldırım, Akın; Gültekin, Kayhan; Husemann, Bernd; Richstone, Douglas O.

    2017-02-01

    Mrk 1216 is a nearby, early-type galaxy with a small effective radius of 2.8 kpc and a large stellar velocity dispersion of 308 km s‑1 for its K-band luminosity of 1.4× {10}11 {L}ȯ . Using integral field spectroscopy assisted by adaptive optics from Gemini North, we measure spatially resolved stellar kinematics within ∼450 pc of the galaxy nucleus. The galaxy exhibits regular rotation with velocities of ±180 km s‑1 and a sharply peaked velocity dispersion profile that reaches 425 km s‑1 at the center. We fit axisymmetric, orbit-based dynamical models to the combination of these high angular resolution kinematics, large-scale kinematics extending to roughly three effective radii, and Hubble Space Telescope imaging, resulting in a constraint of the mass of the central black hole in Mrk 1216. After exploring several possible sources of systematics that commonly affect stellar-dynamical black hole mass measurements, we find a black hole mass of {M}{BH}=(4.9+/- 1.7)× {10}9 {M}ȯ and an H-band stellar mass-to-light ratio of {{{\\Upsilon }}}H=1.3+/- 0.4 {{{\\Upsilon }}}ȯ (1σ uncertainties). Mrk 1216 is consistent with the local black hole mass–stellar velocity dispersion relation, but is a factor of ∼5–10 larger than expectations from the black hole mass–bulge luminosity and black hole mass–bulge mass correlations when conservatively using the galaxy’s total luminosity or stellar mass. This behavior is quite similar to the extensively studied compact galaxy NGC 1277. Resembling the z∼ 2 quiescent galaxies, Mrk 1216 may be a passively evolved descendant, and perhaps reflects a previous era when galaxies contained over-massive black holes relative to their bulge luminosities/masses, and the growth of host galaxies had yet to catch up.

  1. Rapid and Bright Stellar-mass Binary Black Hole Mergers in Active Galactic Nuclei

    Science.gov (United States)

    Bartos, Imre; Kocsis, Bence; Haiman, Zoltán; Márka, Szabolcs

    2017-02-01

    The Laser Interferometer Gravitational-wave Observatory (LIGO) found direct evidence for double black hole binaries emitting gravitational waves. Galactic nuclei are expected to harbor the densest population of stellar-mass black holes. A significant fraction (∼ 30 % ) of these black holes can reside in binaries. We examine the fate of the black hole binaries in active galactic nuclei, which get trapped in the inner region of the accretion disk around the central supermassive black hole. We show that binary black holes can migrate into and then rapidly merge within the disk well within a Salpeter time. The binaries may also accrete a significant amount of gas from the disk, well above the Eddington rate. This could lead to detectable X-ray or gamma-ray emission, but would require hyper-Eddington accretion with a few percent radiative efficiency, comparable to thin disks. We discuss implications for gravitational-wave observations and black hole population studies. We estimate that Advanced LIGO may detect ∼20 such gas-induced binary mergers per year.

  2. Holography, mass area relation and discrete quantum spectrum of black holes

    CERN Document Server

    Lochan, Kinjalk

    2015-01-01

    The quantum genesis of Hawking radiation is a long-standing puzzle in black hole physics. Semi-classically one can argue that the spectrum of radiation emitted by a black hole look very much sparse unlike what is expected from a thermal object. It was demonstrated through a simple quantum model that a quantum black hole will retain a discrete profile, at least in the weak energy regime. However, it was suggested that this discreteness might be an artifact of the simplicity of eigenspectrum of the model considered. Different quantum theories can, in principle, give rise to different complicated spectra and make the radiation from black hole dense enough in transition lines, to make them look continuous in profile. We show that such a hope from a geometry-quantized black hole is not realized as long as large enough black holes are dubbed with holographic relation which tells that the entropy of the black hole can be obtained from the area of the horizon and they have a classical mass area relation. We show that...

  3. Estimates of black-hole natal kick velocities from observations of low-mass X-ray binaries

    CERN Document Server

    Mandel, Ilya

    2015-01-01

    The birth kicks of black holes, arising from asymmetric mass ejection or neutrino emission during core-collapse supernovae, are of great interest for both observationally constraining supernova models and population-synthesis studies of binary evolution. Recently, several efforts were undertaken to estimate black hole birth kicks from observations of black-hole low-mass X-ray binaries. We follow up on this work, specifically focussing on the highest estimated black-hole kick velocities. We find that existing observations do not require black hole birth kicks in excess of approximately 100 km/s, although higher kicks are not ruled out.

  4. The Dynamical Evolution of Stellar-Mass Black Holes in Dense Star Clusters

    Science.gov (United States)

    Morscher, Maggie

    Globular clusters are gravitationally bound systems containing up to millions of stars, and are found ubiquitously in massive galaxies, including the Milky Way. With densities as high as a million stars per cubic parsec, they are one of the few places in the Universe where stars interact with one another. They therefore provide us with a unique laboratory for studying how gravitational interactions can facilitate the formation of exotic systems, such as X-ray binaries containing black holes, and merging double black hole binaries, which are produced much less efficiently in isolation. While telescopes can provide us with a snapshot of what these dense clusters look like at present, we must rely on detailed numerical simulations to learn about their evolution. These simulations are quite challenging, however, since dense star clusters are described by a complicated set of physical processes occurring on many different length and time scales, including stellar and binary evolution, weak gravitational scattering encounters, strong resonant binary interactions, and tidal stripping by the host galaxy. Until very recently, it was not possible to model the evolution of systems with millions of stars, the actual number contained in the largest clusters, including all the relevant physics required describe these systems accurately. The Northwestern Group's Henon Monte Carlo code, CMC, which has been in development for over a decade, is a powerful tool that can be used to construct detailed evolutionary models of large star clusters. With its recent parallelization, CMC is now capable of addressing a particularly interesting unsolved problem in astrophysics: the dynamical evolution of stellar black holes in dense star clusters. Our current understanding of the stellar initial mass function and massive star evolution suggests that young globular clusters may have formed hundreds to thousands of stellar-mass black holes, the remnants of stars with initial masses from 20 - 100

  5. Black Hole Critical Phenomena Without Black Holes

    CERN Document Server

    Liebling, S L

    2000-01-01

    Studying the threshold of black hole formation via numerical evolution has led to the discovery of fascinating nonlinear phenomena. Power-law mass scaling, aspects of universality, and self-similarity have now been found for a large variety of models. However, questions remain. Here I briefly review critical phenomena, discuss some recent results, and describe a model which demonstrates similar phenomena without gravity.

  6. Mass-dependent evolution of the relation between supermassive black hole mass and host spheroid mass since z ~ 1

    CERN Document Server

    Kisaka, Shota

    2010-01-01

    We investigate the evolution of supermassive black hole mass (M_BH) and the host spheroid mass (M_sph) in order to track the history of the M_BH-M_sph relationship. The typical mass increase of M_BH is calculated by a continuity equation and accretion history, which is estimated from the active galactic nucleus (AGN) luminosity function. The increase in M_sph is also calculated by using a continuity equation and a star formation model, which uses observational data for the formation rate and stellar mass function. We find that the black hole to spheroid mass ratio is expected to be substantially unchanged since z~1.2 for high mass objects (M_BH>10^8.5M_SUN and M_sph>10^11.3M_SUN). In the same redshift range, the spheroid mass is found to increase more rapidly than the black hole mass if M_sph>10^11M_SUN. The proposed mass-dependent model is consistent with the current available observational data in the M_BH-M_sph diagram.

  7. Estimate black hole masses of AGNs using ultraviolet emission line properties

    CERN Document Server

    Kong, M Z; Wang, R; Han, J L; Kong, Min-Zhi; Wu, Xue-Bing; Wang, Ran; Han, Jin-Lin

    2005-01-01

    Based on the measured sizes of broad line region of the reverberation-mapping AGN sample, two new empirical relations are introduced to estimate the central black hole masses of radio-loud high-redshift ($z > 0.5$) AGNs. First, using the archival $IUE/HST$ spectroscopy data at UV band for the reverberation-mapping objects, we obtained two new empirical relations between the BLR size and \\Mg/\\C emission line luminosity. Secondly, using the newly determined black hole masses of the reverberation-mapping sample for calibration, two new relationships for determination of black hole mass with the full width of half maximum and the luminosity of \\Mg/\\C line are also found. We then apply the relations to estimate the black hole masses of AGNs in Large Bright Quasar Surveyq and a sample of radio-loud quasars. For the objects with small radio-loudness, the black hole mass estimated using the $R_{\\rm BLR} - L_{\\eMg/\\eC}$ relation is consistent with that from the $R_{BLR} - L_{3000\\AA/1350 \\AA}$ relation. But for radio-...

  8. Bias in C IV-based quasar black hole mass scaling relationships from reverberation mapped samples

    CERN Document Server

    Brotherton, Michael S; Shang, Zhaohui; DiPompeo, M A

    2015-01-01

    The masses of the black holes powering quasars represent a fundamental parameter of active galaxies. Estimates of quasar black hole masses using single-epoch spectra are quite uncertain, and require quantitative improvement. We recently identified a correction for C IV $\\lambda$1549-based scaling relationships used to estimate quasar black hole masses that relies on the continuum-subtracted peak flux ratio of the ultraviolet emission-line blend Si IV + OIV] (the $\\lambda$1400 feature) to that of C IV. This parameter correlates with the suite of associated quasar spectral properties collectively known as "Eigenvector 1" (EV1). Here we use a sample of 85 quasars with quasi-simultaneous optical-ultraviolet spectrophotometry to demonstrate how biases in the average EV1 properties can create systematic biases in C IV-based black hole mass scaling relationships. This effect results in nearly an order of magnitude moving from objects with small $$, which have overestimated black hole masses, to objects with large $$...

  9. Intermediate-mass black holes in globular clusters: observations and simulations

    CERN Document Server

    Lützgendorf, Nora; Gebhardt, Karl; Baumgardt, Holger; Kruijssen, Diederik; Noyola, Eva; Neumayer, Nadine; de Zeeuw, Tim; Feldmeier, Anja; van der Helm, Edwin; Pelupessy, Inti; Zwart, Simon Portegies

    2015-01-01

    The study of intermediate-mass black holes (IMBHs) is a young and promising field of research. Formed by runaway collisions of massive stars in young and dense stellar clusters, intermediate-mass black holes could still be present in the centers of globular clusters, today. Our group investigated the presence of intermediate-mass black holes for a sample of 10 Galactic globular clusters. We measured the inner kinematic profiles with integral-field spectroscopy and determined masses or upper limits of central black holes in each cluster. In combination with literature data we further studied the positions of our results on known black-hole scaling relations (such as M_bh - sigma) and found a similar but flatter correlation for IMBHs. Applying cluster evolution codes, the change in the slope could be explained with the stellar mass loss occurring in clusters in a tidal field over its life time. Furthermore, we present results from several numerical simulations on the topic of IMBHs and integral field units (IFU...

  10. Indication for an intermediate-mass black hole in the globular cluster NGC 5286 from kinematics

    CERN Document Server

    Feldmeier, A; Neumayer, N; Kissler-Patig, M; Gebhardt, K; Baumgardt, H; Noyola, E; de Zeeuw, P T; Jalali, B

    2013-01-01

    Intermediate-mass black holes (IMBHs, 10^2-10^5 M_sun) fill the gap between stellar-mass black holes and supermassive black holes (SMBHs). Simulations have shown that IMBHs may form in dense star clusters, and therefore may still be present in these smaller stellar systems. We investigate the Galactic globular cluster NGC 5286 for indications of a central IMBH using spectroscopic data from VLT/FLAMES, velocity measurements from the Rutgers Fabry Perot at CTIO, and photometric data from HST. We run analytic spherical and axisymmetric Jeans models with different central black-hole masses, anisotropy, mass-to-light ratio, and inclination. Further, we compare the data to a grid of N-body simulations without tidal field. Additionally, we use one N-body simulation to check the results of the spherical Jeans models for the total cluster mass. Both the Jeans models and the N-body simulations favor the presence of a central black hole in NGC 5286 and our detection is at the 1- to 1.5-sigma level. From the spherical Je...

  11. Towards an Extended Binary Black Hole Search using Advanced LIGO: from Stellar to Intermediate-Mass

    Science.gov (United States)

    Mukherjee, Debnandini; LIGO Scientific Collaboration; Virgo Collaboration Collaboration

    2017-01-01

    Intermediate mass black hole (IMBH) binaries, make up the mass space between stellar-mass and super massive black holes, with their total mass in the range of about 100 to 100,000 solar masses. Detection of IMBH mergers would help us explore their formation channels. The IMBH search is currently sensitive to coalescences of black hole binaries covering a total mass range between 50-600 solar masses. Recent publications in astrophysics point to the physical importance of the IMBH search (they may shed light on certain supernova mechanisms). In light of the conclusion of the 1st Advanced LIGO search conducted between September 2015 and January 2016 (O1 run), I will provide an update on the IMBH search (software GstLAL based, using matched-filter) on this data and will discuss the feasibility of including the IMBH search with the stellar-mass black hole search space (total mass range 2-100 solar masses), thus achieving a combined search for future runs. NSF PHY-1607585.

  12. Black holes in stellar-mass binary systems: expiating original spin?

    Science.gov (United States)

    King, Andrew; Nixon, Chris

    2016-10-01

    We investigate systematically whether accreting black hole systems are likely to reach global alignment of the black hole spin and its accretion disc with the binary plane. In low-mass X-ray binaries (LMXBs), there is only a modest tendency to reach such global alignment, and it is difficult to achieve fully: except for special initial conditions, we expect misalignment of the spin and orbital planes by ˜1 rad for most of the LMXB lifetime. The same is expected in high-mass X-ray binaries. A fairly close approach to global alignment is likely in most stellar-mass ultraluminous X-ray binary systems (ULXs) where the companion star fills its Roche lobe and transfers mass on a thermal or nuclear time-scale to a black hole of lower mass. These systems are unlikely to show orbital eclipses, as their emission cones are close to the hole's spin axis. This offers a potential observational test, as models for ULXs invoking intermediate-mass black holes do predict eclipses for ensembles of ≳ 10 systems. Recent observational work shows that eclipses are either absent or extremely rare in ULXs, supporting the picture that most ULXs are stellar-mass binaries with companion stars more massive than the accretor.

  13. A Lower Limit on the Halo Mass to form Supermassive Black Holes

    CERN Document Server

    Dotan, Calanit; Shaviv, Nir J

    2011-01-01

    We consider a scenario where supermassive black holes form through direct accumulation of gas at the centre of proto-galaxies. In the first stage, the accumulated gas forms a super-massive star whose core collapses when the nuclear fuel is exhausted, forming a black hole of $M_{\\rm BH} \\approx 100 M_{\\sun}$. As the black hole starts accreting, it inflates the surrounding dense gas into an almost hydrostatic self-gravitating envelope, with at least 10-100 times the mass of the hole. We find that these "quasistars" suffer extremely high rates of mass loss through winds from their envelopes, in analogy to very massive stars such as eta-Carinae. Only for envelope masses greater than 2.8 \\times 10^{5} (M_{\\rm BH}/100 M_{\\sun})^{9/11} is the envelope evaporation time-scale longer than the accretion time-scale of the black hole. This relation thus constitutes a "threshold growth line" above which quasistars can grow their internal black holes. Accretion rates can be 10 to 100 times the Eddington rate. The quasistars...

  14. The black hole - bulge mass relation in active and inactive galaxies

    OpenAIRE

    McLure, R. J.; Dunlop, J. S.

    2002-01-01

    New virial black-hole mass estimates are presented for a sample of 72 AGN covering three decades in optical luminosity. Using a model in which the AGN broad-line region (BLR) has a flattened geometry, we investigate the M_{bh)-L_{bulge} relation for a combined 90-object sample, consisting of the AGN plus a sample of 18 nearby inactive elliptical galaxies with dynamical black-hole mass measurements. It is found that, for all reasonable mass-to-light ratios, the M_{bh}-L_{bulge} relation is equ...

  15. Enhancing our Search for Missing Intermediate Mass Black Holes Using Advanced LIGO

    Science.gov (United States)

    Jani, Karan; LIGO Scientific Collaboration; Virgo Collaboration Collaboration

    2017-01-01

    The current generation of ground-based gravitational-wave detectors are most sensitive to mergers of intermediate-mass black holes (IMBH), with search volume of cosmological distances of redshift 1 and detectable total-mass up to 1000M⊙ . Two independent searches for binary black holes, matched-filtering and transient burst, are specifically configured to look for IMBH binaries in Advanced LIGO. I summarize the results from both these searches during the first observing run of Advanced LIGO and narrate our plans to enhance detection volume and detectable total-mass.

  16. Determination of Black Hole Masses in Galactic Black Hole Binaries using Scaling of Spectral and Variability Characteristics

    CERN Document Server

    Shaposhnikov, Nickolai

    2009-01-01

    We present a study of correlations between X-ray spectral and timing properties observed from a number of Galactic Black Hole (BH) binaries during hard-soft state spectral evolution. We analyze 17 transition episodes from 8 BH sources observed with RXTE. Our scaling technique for BH mass determination uses a correlation between spectral index and quasi-periodic oscillation (QPO) frequency. In addition, we use a correlation between index and the normalization of the disk "seed" component to cross-check the BH mass determination and estimate the distance to the source. While the index-QPO correlations for two given sources contain information on the ratio of the BH masses in those sources, the index-normalization correlations depend on the ratio of the BH masses and the distance square ratio. In fact, the index-normalization correlation also discloses the index-mass accretion rate saturation effect given that the normalization of disk "seed" photon supply is proportional to the disk mass accretion rate. We pres...

  17. Constraining the formation of black holes in short-period black hole low-mass X-ray binaries

    Science.gov (United States)

    Repetto, Serena; Nelemans, Gijs

    2015-11-01

    The formation of stellar-mass black holes (BHs) is still very uncertain. Two main uncertainties are the amount of mass ejected in the supernova (SN) event (if any) and the magnitude of the natal kick (NK) the BH receives at birth (if any). Repetto et al., studying the position of Galactic X-ray binaries containing BHs, found evidence for BHs receiving high NKs at birth. In this paper, we extend that study, taking into account the previous binary evolution of the sources as well. The seven short-period BH X-ray binaries that we use are compact binaries consisting of a low-mass star orbiting a BH in a period less than 1 d. We trace their binary evolution backwards in time, from the current observed state of mass transfer, to the moment the BH was formed, and we add the extra information on the kinematics of the binaries. We find that several systems could be explained by no NK, just mass ejection, while for two systems (and possibly more) a high kick is required. So unless the latter have an alternative formation, such as within a globular cluster, we conclude that at least some BHs get high kicks. This challenges the standard picture that BH kicks would be scaled down from neutron star kicks. Furthermore, we find that five systems could have formed with a non-zero NK but zero mass ejected (i.e. no SN) at formation, as predicted by neutrino-driven NKs.

  18. The Black Hole Mass-Bulge Luminosity Relationship for Active Galactic Nuclei From Reverberation Mapping and Hubble Space Telescope Imaging

    DEFF Research Database (Denmark)

    Bentz, Misty C.; Peterson, Bradley M.; Pogge, Richard W.

    2009-01-01

    We investigate the relationship between black hole mass and bulge luminosity for active galactic nuclei (AGNs) with reverberation-based black hole mass measurements and bulge luminosities from two-dimensional decompositions of Hubble Space Telescope host galaxy images. We find that the slope...... of the relationship for AGNs is 0.76-0.85 with an uncertainty of ~0.1, somewhat shallower than the M BH vprop L 1.0±0.1 relationship that has been fit to nearby quiescent galaxies with dynamical black hole mass measurements. This difference is somewhat perplexing, as the AGN black hole masses include an overall...

  19. The Influence of Black Hole Mass and Accretion Rate on the FRI/FRII Radio Galaxy Dichotomy

    Science.gov (United States)

    Wold, M.; Lacy, M.; Armus, L.

    We use medium resolution optical spectra of 3CR radio galaxies to estimate their black hole masses and accretion rates. Black hole masses are found from central stellar velocity dispersions, and accretion rates are derived from narrow emission-line luminosities. The sample covers both Fanaroff-Riley (FR) classes; the more powerful FRIIs and the less powerful FRIs. We find that FRIs and FRIIs separate in diagrams of radio luminosity and narrow-line luminosity versus black hole mass. This suggests that, at a given black hole mass, the FRIIs accrete more efficiently, or accrete more matter, than FRIs.

  20. Remnant mass, spin, and recoil from spin aligned black-hole binaries

    CERN Document Server

    Healy, James; Zlochower, Yosef

    2014-01-01

    We perform a set of 36 nonprecessing black-hole binary simulations with spins either aligned or counteraligned with the orbital angular momentum in order to model the final mass, spin, and recoil of the merged black hole as a function of the individual black hole spin magnitudes and the mass ratio of the progenitors. We find that the maximum recoil for these configurations is $V_{max}=526\\pm23\\,km/s$, which occurs when the progenitor spins are maximal, the mass ratio is $q_{max}=m_1/m_2=0.623\\pm0.038$, the smaller black-hole spin is aligned with the orbital angular momentum, and the larger black-hole spin is counteraligned ($\\alpha_1=-\\alpha_2=1$). This maximum recoil is about $80\\,km/s$ larger than previous estimates, but most importantly, because the maximum occurs for smaller mass ratios, the probability for a merging binary to recoil faster than $400\\,km/s$ can be as large as $17\\%$, while the probability for recoils faster than $250\\, km/s$ can be as large as $45\\%$. We provide explicit phenomenological ...

  1. The Formation of Supermassive Black Holes from Low-Mass Pop III Seeds

    CERN Document Server

    Whalen, Daniel J

    2011-01-01

    The existence of 10$^9$ M$_{\\odot}$ black holes (BH) in massive galaxies by $z \\sim 7$ is one of the great unsolved mysteries in cosmological structure formation. One leading model argues that they originate from much smaller seeds at high redshift and then accrete at the Eddington limit down to the epoch of reionization, which requires that they have constant access to rich supplies of fuel. Because early numerical simulations suggested that many first stars had masses $\\gtrsim 100$ M$_{\\odot}$, the supermassive black hole (SMBH) seeds in this model were 100 - 300 M$_{\\odot}$ black holes formed by Pop III stars at $z \\sim 20$. However, there is growing numerical and observational evidence that most Pop III stars were tens of solar masses, not hundreds, and consequently that 20 - 140 M$_{\\odot}$ black holes may have been much more plentiful at high redshift. We have examined low-mass Pop III black holes as potential seeds of SMBH and find that the mass range for possible seeds is severely constrained. Progeni...

  2. Estimating Black Hole Masses of AGNs using Ultraviolet Emission Line Properties

    Institute of Scientific and Technical Information of China (English)

    Min-Zhi Kong; Xue-Bing Wu; Ran Wang; Jin-Lin Han

    2006-01-01

    Based on measured broad line region sizes in the reverberation-mapping AGN sample, two new empirical relations are introduced to estimate the central black hole masses of radio-loud high-redshift (z > 0.5) AGNs. First, using the archival IUE/HST spectroscopy data at UV band for the reverberation-mapping objects, we obtained two new empirical relations between the BLR size and Mg Ⅱ/C Ⅳ emission line luminosity. Secondly, using the newly determined black hole masses of the reverberation-mapping sample as calibration, we found two new relationships for determining the black hole mass with the full width at half maximum and the luminosity of Mg Ⅱ/C Ⅳ line. We then apply the relations to estimate the black hole masses of the AGNs in the Large Bright Quasar Survey and a sample of radio-loud quasars. For the objects with small radio-loudness, the black hole mass estimated using the RBLR-LMg Ⅱ/C Ⅳ relation is consistent with that from the RBLR-L3000(A)/1350(A) relation. For radio-loud AGNs, however, the mass estimated from the RBLR-LMg Ⅱ/C Ⅳ relation is systematically lower than that from the continuum luminosity L3000 (A)/1350 (A).Because jets could have significant contributions to the UV/optical continuum luminosity of radio-loud AGNs,we emphasize once again that for radio-loud AGNs, the emission line luminosity may be a better tracer of the ionizing luminosity than the continuum luminosity, so that the relations between the BLR size and UV emission line luminosities should be used to estimate the black hole masses of high redshift radio-loud AGNs.

  3. A method to constrain mass and spin of GRB black hole central engine within the NDAF $\

    CERN Document Server

    Liu, Tong; Zhao, Xiao-Hong; Zhang, Fu-Wen; Zhang, Bing

    2015-01-01

    Black holes (BHs) hide themselves behind various astronomical phenomena, and their properties, i.e., mass and spin, are usually difficult to constrain. One leading candidate for the central engine model of gamma-ray bursts (GRBs) invokes a stellar mass BH and a neutrino-dominated accretion flow (NDAF), with the relativistic jet launched due to neutrino-anti-neutrino ($\

  4. Super-Critical Growth of Massive Black Holes from Stellar-Mass Seeds

    CERN Document Server

    Madau, Piero; Dotti, Massimo

    2014-01-01

    We consider super-critical accretion with angular momentum onto stellar-mass black holes as a possible mechanism for growing billion-solar-mass holes from light seeds at early times. We use the radiatively-inefficient "slim disk" solution -- advective, optically thick flows that generalize the standard geometrically thin disk model -- to show how mildly super-Eddington intermittent accretion may significantly ease the problem of assembling the first massive black holes when the Universe was less than 0.8 Gyr old. Because of the low radiative efficiencies of slim disks around non-rotating as well as rapidly rotating holes, the mass e-folding timescale in this regime is nearly independent of the spin parameter. The conditions that may lead to super-critical growth in the early Universe are briefly discussed.

  5. Black holes in stellar-mass binary systems: expiating original spin?

    CERN Document Server

    King, Andrew

    2016-01-01

    We investigate systematically whether accreting black hole systems are likely to reach global alignment of the black hole spin and its accretion disc with the binary plane. In low-mass X-ray binaries (LMXBs) there is only a modest tendency to reach such global alignment, and it is difficult to achieve fully: except for special initial conditions we expect misalignment of the spin and orbital planes by ~1 radian for most of the LMXB lifetime. The same is expected in high-mass X-ray binaries (HMXBs). A fairly close approach to global alignment is likely in most stellar-mass ultraluminous X-ray binary systems (ULXs) where the companion star fills its Roche lobe and transfers on a thermal timescale to a black hole of lower mass. These systems are unlikely to show orbital eclipses, as their emission cones are close to the hole's spin axis. This offers a potential observational test, as models for ULXs invoking intermediate-mass black holes do predict eclipses for ensembles of > ~10 systems. Recent observational wo...

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

    CERN Document Server

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

    2013-01-01

    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...

  7. On the Black Hole - Bulge Mass Ratios in Narrow-Line Seyfert 1 Galaxies

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    We present estimated ratios of the central black hole mass to the bulgemass (Mbh/Mbulge) for 15 Narrow Line Seyfert 1 galaxies (NLS1s). It is found thatNLS1s apparently have lower mass ratios: the average mass ratio is about 1 × 10-4with a spread of 2, which is one order of magnitude lower than for Broad Line AGNsand quiescent galaxies. This lower value, as compared to that established essentiallyfor all other types of galaxies, can be accounted for by an underestimation of theblack hole masses and an overestimation of the bulge masses in the NLS1s.

  8. Limits on the Mass and Abundance of Primordial Black Holes from Quasar Gravitational Microlensing

    Science.gov (United States)

    Mediavilla, E.; Jiménez-Vicente, J.; Muñoz, J. A.; Vives-Arias, H.; Calderón-Infante, J.

    2017-02-01

    The idea that dark matter can be made of intermediate-mass primordial black holes (PBHs) in the 10 M ⊙ ≲ M ≲ 200 M ⊙ range has recently been reconsidered, particularly in the light of the detection of gravitational waves by the LIGO experiment. The existence of even a small fraction of dark matter in black holes should nevertheless result in noticeable quasar gravitational microlensing. Quasar microlensing is sensitive to any type of compact objects in the lens galaxy, to their abundance, and to their mass. We have analyzed optical and X-ray microlensing data from 24 gravitationally lensed quasars to estimate the abundance of compact objects in a very wide range of masses. We conclude that the fraction of mass in black holes or any type of compact objects is negligible outside of the 0.05 M ⊙ ≲ M ≲ 0.45 M ⊙ mass range and that it amounts to 20% ± 5% of the total matter, in agreement with the expected masses and abundances of the stellar component. Consequently, the existence of a significant population of intermediate-mass PBHs appears to be inconsistent with current microlensing observations. Therefore, primordial massive black holes are a very unlikely source of the gravitational radiation detected by LIGO.

  9. The closest black holes

    CERN Document Server

    Fender, Rob; Heywood, Ian

    2013-01-01

    Starting from the assumption that there is a large population (> 10^8) of isolated, stellar-mass black holes (IBH) distributed throughout our galaxy, we consider the detectable signatures of accretion from the interstellar medium (ISM) that may be associated with such a population. We simulate the nearby (radius 250 pc) part of this population, corresponding to the closest ~35 000 black holes, using current best estimates of the mass distribution of stellar mass black holes combined with two models for the velocity distribution of stellar-mass IBH which bracket likely possibilities. We distribute this population of objects appropriately within the different phases of the ISM and calculate the Bondi-Hoyle accretion rate, modified by a further dimensionless efficiency parameter \\lambda. Assuming a simple prescription for radiatively inefficient accretion at low Eddington ratios, we calculate the X-ray luminosity of these objects, and similarly estimate the radio luminosity from relations found empirically for b...

  10. A mass of less than 15 solar masses for the black hole in an ultraluminous X-ray source.

    Science.gov (United States)

    Motch, C; Pakull, M W; Soria, R; Grisé, F; Pietrzyński, G

    2014-10-01

    Most ultraluminous X-ray sources have a typical set of properties not seen in Galactic stellar-mass black holes. They have luminosities of more than 3 × 10(39) ergs per second, unusually soft X-ray components (with a typical temperature of less than about 0.3 kiloelectronvolts) and a characteristic downturn in their spectra above about 5 kiloelectronvolts. Such puzzling properties have been interpreted either as evidence of intermediate-mass black holes or as emission from stellar-mass black holes accreting above their Eddington limit, analogous to some Galactic black holes at peak luminosity. Recently, a very soft X-ray spectrum was observed in a rare and transient stellar-mass black hole. Here we report that the X-ray source P13 in the galaxy NGC 7793 is in a binary system with a period of about 64 days and exhibits all three canonical properties of ultraluminous sources. By modelling the strong optical and ultraviolet modulations arising from X-ray heating of the B9Ia donor star, we constrain the black hole mass to be less than 15 solar masses. Our results demonstrate that in P13, soft thermal emission and spectral curvature are indeed signatures of supercritical accretion. By analogy, ultraluminous X-ray sources with similar X-ray spectra and luminosities of up to a few times 10(40) ergs per second can be explained by supercritical accretion onto massive stellar-mass black holes.

  11. C IV emission-line properties and systematic trends in quasar black hole mass estimates

    Science.gov (United States)

    Coatman, Liam; Hewett, Paul C.; Banerji, Manda; Richards, Gordon T.

    2016-09-01

    Black hole masses are crucial to understanding the physics of the connection between quasars and their host galaxies and measuring cosmic black hole-growth. At high redshift, z ≳ 2.1, black hole masses are normally derived using the velocity width of the C IV λ λ1548, 1550 broad emission line, based on the assumption that the observed velocity widths arise from virial-induced motions. In many quasars, the C IV emission line exhibits significant blue asymmetries (`blueshifts') with the line centroid displaced by up to thousands of km s-1 to the blue. These blueshifts almost certainly signal the presence of strong outflows, most likely originating in a disc wind. We have obtained near-infrared spectra, including the Hα λ6565 emission line, for 19 luminous (LBol = 46.5-47.5 erg s-1) Sloan Digital Sky Survey quasars, at redshifts 2 blueshifts present in the population. A strong correlation between C IV velocity width and blueshift is found and, at large blueshifts, >2000 km s-1, the velocity widths appear to be dominated by non-virial motions. Black hole masses, based on the full width at half-maximum of the C IV emission line, can be overestimated by a factor of 5 at large blueshifts. A larger sample of quasar spectra with both C IV and H β, or Hα, emission lines will allow quantitative corrections to C IV-based black hole masses as a function of blueshift to be derived. We find that quasars with large C IV blueshifts possess high Eddington luminosity ratios and that the fraction of high-blueshift quasars in a flux-limited sample is enhanced by a factor of approximately 4 relative to a sample limited by black hole mass.

  12. Growing massive black holes through super-critical accretion of stellar-mass seeds

    CERN Document Server

    Lupi, A; Dotti, M; Fiacconi, D; Mayer, L; Madau, P

    2015-01-01

    The rapid assembly of the massive black holes that power the luminous quasars observed at $z \\sim 6-7$ remains a puzzle. Various direct collapse models have been proposed to head-start black hole growth from initial seeds with masses $\\sim 10^5\\,\\rm M_\\odot$, which can then reach a billion solar mass while accreting at the Eddington limit. Here we propose an alternative scenario based on radiatively inefficient super-critical accretion of stellar-mass holes embedded in the gaseous circum-nuclear discs (CNDs) expected to exist in the cores of high redshift galaxies. Our sub-pc resolution hydrodynamical simulations show that stellar-mass holes orbiting within the central 100 pc of the CND bind to very high density gas clumps that arise from the fragmentation of the surrounding gas. Owing to the large reservoir of dense cold gas available, a stellar-mass black hole allowed to grow at super-Eddington rates according to the "slim disc" solution can increase its mass by 3 orders of magnitudes within a few million y...

  13. A Population of Relic Intermediate-Mass Black Holes in the Halo of the Milky Way

    CERN Document Server

    Rashkov, Valery

    2013-01-01

    If "seed" central black holes were common in the subgalactic building blocks that merged to form present-day massive galaxies, then relic intermediate-mass black holes (IMBHs) should be present in the Galactic bulge and halo. We use a particle tagging technique to dynamically populate the N-body Via Lactea II high-resolution simulation with black holes, and assess the size, properties, and detectability of the leftover population. The method assigns a black hole to the most tightly bound central particle of each subhalo at infall according to an extrapolation of the M_BH-sigma_* relation, and self-consistently follows the accretion and disruption of Milky Way progenitor dwarfs and their holes in a cosmological "live" host from high redshift to today. We show that, depending on the minimum stellar velocity dispersion, sigma_m, below which central black holes are assumed to be increasingly rare, as many as ~2000 (sigma_m=3 km/s) or as few as ~70 (sigma_m=12 km/s) IMBHs may be left wandering in the halo of the M...

  14. Jetted Tidal Disruptions of Stars as a Flag of Intermediate Mass Black Holes at High Redshifts

    CERN Document Server

    Fialkov, Anastasia

    2016-01-01

    Tidal disruption events (TDEs) of stars by single or binary supermassive black holes (SMBHs) brighten galactic nuclei and reveal a population of otherwise dormant black holes. Adopting event rates from the literature, we aim to establish general trends in the redshift evolution of the TDE number counts and their observable signals. We pay particular attention to two types of TDEs which are expected to be observable out to high redshifts, namely (i) jetted TDEs whose luminosity is boosted by relativistic beaming, and (ii) TDEs around binary black holes. We show that the brightest (jetted) TDEs are expected to be produced by massive black hole binaries if the occupancy of intermediate mass black holes (IMBHs) in low mass galaxies is high. The same binary population will also provide gravitational wave sources for eLISA. In addition, we find that the shape of the X-ray luminosity function of TDEs strongly depends on the occupancy of IMBHs and could be used to constrain scenarios of SMBH formation. Finally, we ma...

  15. Energy, momentum and mass outflows and feedback from thick accretion discs around rotating black holes

    CERN Document Server

    Sadowski, A; Penna, R; Zhu, Y

    2013-01-01

    A set of long-duration general relativistic magnetohydrodynamic simulations of radiatively inefficient accretion discs around rotating black holes are presented, and are used to estimate the energy, mass and momentum outflow rates from such systems. Outflows occur via two fairly distinct modes: a relativistic jet and a sub-relativistic wind. The jet power depends strongly on the black hole spin and on the magnetic flux at the horizon. Unless these are very small, the energy output in the jet dominates over that in the wind. In the limit of a rapidly spinning black hole accreting in the magnetically arrested limit, when the magnetic flux at the black hole is maximum, the jet power exceeds the total rate of accretion of rest mass energy. However, because of strong collimation, the jet probably does not have a significant effect on its surrounding. In the case of an accreting supermassive black hole, external feedback via a jet is likely important only on the largest galaxy cluster scales. The power in the wind ...

  16. Intermediate-mass black holes in globular clusters: observations and simulations - Update

    Science.gov (United States)

    Lützgendorf, Nora; Kissler-Patig, Markus; Gebhardt, Karl; Baumgardt, Holger; Kruijssen, Diederik; Noyola, Eva; Neumayer, Nadine; de Zeeuw, Tim; Feldmeier-Krause, Anja; van der Helm, Edwin; Pelupessy, Inti; Zwart, Simon Portegies

    2017-03-01

    The study of intermediate-mass black holes (IMBHs) is a young and promising field of research. If IMBH exist, they could explain the rapid growth of supermassive black holes by acting as seeds in the early stage of galaxy formation. Formed by runaway collisions of massive stars in young and dense stellar clusters, intermediate-mass black holes could still be present in the centers of globular clusters, today. We measured the inner kinematic profiles with integral-field spectroscopy for 10 Galactic globular cluster and determined masses or upper limits of central black holes. In combination with literature data we further studied the positions of our results on known black-hole scaling relations (such as M • - σ) and found a similar but flatter correlation for IMBHs. Applying cluster evolution codes, the change in the slope could be explained with the stellar mass loss occurring in clusters in a tidal field over its life time. Furthermore, we present results from several numerical simulations on the topic of IMBHs and integral field units (IFUs). N-body simulations were used to simulate IFU data cubes. For the specific case of NGC 6388 we simulated two different IFU techniques and found that velocity dispersion measurements from individual velocities are strongly biased towards lower values due to blends of neighbouring stars and background light. In addition, we use the Astrophysical Multipurpose Software Environment (AMUSE) to combine gravitational physics, stellar evolution and hydrodynamics to simulate the accretion of stellar winds onto a black hole. We find that the S-stars need to provide very strong winds in order to explain the accretion rate in the galactic center.

  17. On the evolution of the intrinsic scatter in black hole versus galaxy mass relations

    CERN Document Server

    Hirschmann, M; Burkert, A; Naab, T; Genel, S; Somerville, R

    2010-01-01

    We present results on the evolution of the intrinsic scatter of black hole masses considering different implementations of a model in which black holes only grow via mergers. We demonstrate how merger driven growth affects the correlations between black hole mass and host bulge mass. The simple case of an initially log-normal distributed scatter in black hole and bulge masses combined with random merging within the galaxy population results in a decreasing scatter with merging generation/number as predicted by the Central-limit theorem. In general we find that the decrease in scatter {\\sigma} is well approximated by {\\sigma}merg(m) = {\\sigma}ini \\times (m + 1)^(-a/2) with a = 0.42 for a range of mean number of mergers m 100) we find a convergence to a = 0.61. This is valid for a wide range of different initial distributions, refill-scenarios or merger mass-ratios. Growth scenarios based on halo merger trees of a (100 Mpc)^3 dark matter LambdaCDM-simulation show a similar behaviour with a scatter decrease of ...

  18. Black Hole Masses of Intermediate-Redshift Quasars: Near Infrared Spectroscopy

    CERN Document Server

    Dietrich, Matthias; Grupe, Dirk; Komossa, S

    2009-01-01

    We present near-infrared spectra of ten luminous, intermediate redshift quasars observed with SofI at the NTT of ESO/La Silla. With these rest-frame optical spectra we probe the Hb -[OIII] emission line region. Using the standard scaling relation involving the width of the Hb line and the continuum luminosity, we measure black hole masses in the range of ~2x10^9 to 10^10 Msol. We also used SDSS spectra to probe MgII2798 and CIV1549 emission lines and used these for black hole mass measurements as well. The massive black holes we observe could not have grown by simple radiatively efficient accretion at the observed accretion rate starting from seeds of up to thousand solar masses. About 10% of the observed black hole mass must have been accumulated by earlier merger events and radiatively inefficient accretion. Radiatively efficient accretion would further grow these BHs to masses of several 10^9 Msol in 2 to 3 e-folding times i.e. in several 10^8yrs. The Hb-based Eddington luminosity ratios are in the range o...

  19. Black hole critical phenomena without black holes

    Indian Academy of Sciences (India)

    Steven L Liebling

    2000-10-01

    Studying the threshold of black hole formation via numerical evolution has led to the discovery of fascinating nonlinear phenomena. Power-law mass scaling, aspects of universality, and self-similarity have now been found for a large variety of models. However, questions remain. Here I briefly review critical phenomena, discuss some recent results, and describe a model which demonstrates similar phenomena without gravity.

  20. N -body modelling of globular clusters: masses, mass-to-light ratios and intermediate-mass black holes

    Science.gov (United States)

    Baumgardt, H.

    2017-01-01

    We have determined the masses and mass-to-light ratios of 50 Galactic globular clusters by comparing their velocity dispersion and surface brightness profiles against a large grid of 900 N-body simulations of star clusters of varying initial concentration, size and central black hole mass fraction. Our models follow the evolution of the clusters under the combined effects of stellar evolution and two-body relaxation allowing us to take the effects of mass segregation and energy equipartition between stars self-consistently into account. For a subset of 16 well-observed clusters, we also derive their kinematic distances. We find an average mass-to-light ratio of Galactic globular clusters of =1.98 ± 0.03, which agrees very well with the expected M/L ratio if the initial mass function (IMF) of the clusters was a standard Kroupa or Chabrier mass function. We do not find evidence for a decrease in the average mass-to-light ratio with metallicity. The surface brightness and velocity dispersion profiles of most globular clusters are incompatible with the presence of intermediate-mass black holes (IMBHs) with more than a few thousand M⊙ in them. The only clear exception is ω Cen, where the velocity dispersion profile provides strong evidence for the presence of a ˜40 000 M⊙ IMBH in the centre of the cluster.

  1. N-body modeling of globular clusters: Masses, mass-to-light ratios and intermediate-mass black holes

    Science.gov (United States)

    Baumgardt, H.

    2016-10-01

    We have determined the masses and mass-to-light ratios of 50 Galactic globular clusters by comparing their velocity dispersion and surface brightness profiles against a large grid of 900 N-body simulations of star clusters of varying initial concentration, size and central black hole mass fraction. Our models follow the evolution of the clusters under the combined effects of stellar evolution and two-body relaxation allowing us to take the effects of mass segregation and energy equipartition between stars self-consistently into account. For a subset of 16 well observed clusters we also derive their kinematic distances. We find an average mass-to-light ratio of Galactic globular clusters of =1.98 ± 0.03, which agrees very well with the expected M/L ratio if the initial mass function (IMF) of the clusters was a standard Kroupa or Chabrier mass function. We do not find evidence for a decrease of the average mass-to-light ratio with metallicity. The surface brightness and velocity dispersion profiles of most globular clusters are incompatible with the presence of intermediate-mass black holes (IMBHs) with more than a few thousand M⊙ in them. The only clear exception is ω Cen, where the velocity dispersion profile provides strong evidence for the presence of a ˜40,000 M⊙ IMBH in the centre of the cluster.

  2. Astrophysical Black Holes in the Physical Universe

    CERN Document Server

    Zhang, Shuang-Nan

    2010-01-01

    In this chapter I focus on asking and answering the following questions: (1) What is a black hole? Answer: There are three types of black holes, namely mathematical black holes, physical black holes and astrophysical black holes. An astrophysical black hole, with mass distributed within its event horizon but not concentrated at the singularity point, is not a mathematical black hole. (2) Can astrophysical black holes be formed in the physical universe? Answer: Yes, at least this can be done with gravitational collapse. (3) How can we prove that what we call astrophysical black holes are really black holes? Answer: Finding direct evidence of event horizon is not the way to go. Instead I propose five criteria which meet the highest standard for recognizing new discoveries in experimental physics and observational astronomy. (4) Do we have sufficient evidence to claim the existence of astrophysical black holes in the physical universe? Answer: Yes, astrophysical black holes have been found at least in some galac...

  3. Improved Dynamical Constraints on the Mass of the central Black Hole in NGC 404

    CERN Document Server

    Nguyen, Dieu D; Brok, Mark den; Neumayer, Nadine; Cappellari, Michele; Barth, Aaron J; Caldwell, Nelson; Williams, Benjamin F; Binder, Breanna

    2016-01-01

    We explore the nucleus of the nearby 10$^9$\\Msun~early-type galaxy (ETGs), NGC~404, using \\emph{Hubble Space Telescope} (\\hst)/STIS spectroscopy and WFC3 imaging. We first present evidence for nuclear variability in UV, optical, and infrared filters over a time period of 15~years. This variability adds to the already substantial evidence for an accreting black hole at the center of NGC~404. We then redetermine the dynamical black hole mass in NGC~404 including modeling of the nuclear stellar populations. We combine \\hst/STIS spectroscopy with WFC3 images to create a local color--\\ml~relation derived from stellar population modeling of the STIS data. We then use this to create a mass model for the nuclear region. We use Jeans modeling to fit this mass model to adaptive optics (AO) stellar kinematic observations from Gemini/NIFS. From our stellar dynamical modeling, we find a 3$\\sigma$ upper limit on the black hole mass of $1.5\\times10^5$\\Msun. Given the accretion evidence for a black hole, this upper limit mak...

  4. Observational Evidence for Intermediate-Mass Black Holes in Ultra-luminous X-ray Sources

    CERN Document Server

    Colbert, E J M

    2004-01-01

    Evidence is mounting that some Ultra-luminous X-ray sources (ULXs) may contain accreting intermediate-mass black holes (IMBHs). We review the current observational evidence for IMBH-ULXs. While low-luminosity ULXs with L_X ~ 10^40 ergs, we suggest that this class of ULXs is generally powered by accreting IMBHs.

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

    DEFF Research Database (Denmark)

    Denney, Kelly D.; Peterson, Bradley M.; Dietrich, Matthias

    2008-01-01

    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...

  6. The jet power, radio loudness and black hole mass in radio loud AGNs

    CERN Document Server

    Liu, Y; Gu, M F; Liu, Yi; Jiang, Dong Rong; Gu, Min Feng

    2006-01-01

    The jet formation is thought to be closely connected with the mass of central supermassive black hole in Active Galactic Nuclei. The radio luminosity commonly used in investigating this issue is merely an indirect measure of the energy transported through the jets from the central engine, and severely Doppler boosted in core-dominated radio quasars. In this work, we investigate the relationship between the jet power and black hole mass, by estimating the jet power using extrapolated extended 151 MHz flux density from the VLA 5 GHz extended radio emission, for a sample of 146 radio loud quasars complied from literature. After removing the effect of relativistic beaming in the radio and optical emission, we find a significant intrinsic correlation between the jet power and black hole mass. It strongly implies that the jet power, so as jet formation, is closely connected with the black hole mass.To eliminate the beaming effect in the conventional radio loudness, we define a new radio loudness as the ratio of the...

  7. Upper limits on the mass of supermassive black holes from HST/STIS archival data

    NARCIS (Netherlands)

    Corsini, E. M.; Beifiori, A.; Bontá, E. D.; Pizzella, A.; Coccato, L.; Sarzi, M.; Bertola, F.

    2006-01-01

    Abstract: The growth of supermassive black holes (SBHs) appears to be closely linked with the formation of spheroids. There is a pressing need to acquire better statistics on SBH masses, since the existing samples are preferentially weighted toward early-type galaxies with very massive SBHs. With th

  8. Evidence for an Intermediate Mass Black Hole in NGC 5408 X-1

    Science.gov (United States)

    Strohmayer, Tod E.; Mushotzky, Richard F.

    2009-01-01

    We report the discovery with XMM-Newton of correlated spectral and timing behavior in the ultraluminous X-ray source (ULX) NGC 5408 X-1. An approx. 100 ksec pointing with XMM/Newton obtained in January, 2008 reveals a strong 10 mHz QPO in the > 1 keV flux, as well as flat-topped, band limited noise breaking to a power law. The energy spectrum is again dominated by two components, a 0.16 keV thermal disk and a power-law with an index of approx. 2.5. These new measurements, combined with results from our previous January 2006 pointing in which we first detected QPOs, show for the first time in a ULX a pattern of spectral and temporal correlations strongly analogous to that seen in Galactic black hole sources, but at much higher X-ray luminosity and longer characteristic time-scales. We find that the QPO frequency is proportional to the inferred disk flux, while the QPO and broad-band noise amplitude (root mean squared, rms) are inversely proportional to the disk flux. Assuming that QPO frequency scales inversely with black hole mass at a given power-law spectral index we derive mass estimates using the observed QPO frequency - spectral index relations from five stellar-mass black hole systems with dynamical mass constraints. The results from all sources are consistent with a mass range for NGC 5408 X-1 from 1000 - 9000 Stellar mass. We argue that these are conservative limits, and a more likely range is from 2000 - 5000 Stellar mass. Moreover, the recent relation from Gierlinski et al. that relates black hole mass to the strength of variability at high frequencies (above the break in the power spectrum), and the variability plane results of McHardy et al. and Koerding et al., are also suggestive of such a. high mass for NGC 5408 X-1. Importantly, none of the above estimates appears consistent with a black hole mass less than approx. 1000 Stellar mass for NGC 5408 X-1. We argue that these new findings strongly support the conclusion that NGC 5408 X-1 harbors an

  9. Hawking Radiation of Mass Generating Particles from Dyonic Reissner–Nordström Black Hole

    Indian Academy of Sciences (India)

    I. Sakalli; A Ovgun

    2016-09-01

    The Hawking radiation is considered as a quantum tunneling process, which can be studied in the framework of the Hamilton--Jacobi method. In this study, we present the wave equation for a mass generating massive and charged scalar particle (boson). In sequel, we analyse the quantum tunneling of these bosons from a generic 4-dimensional spherically symmetric black hole. We apply the Hamilton--Jacobi formalism to derive the radial integral solution for the classically forbidden action which leads to the tunneling probability. To support our arguments, we take the dyonic Reissner--Nordström black hole as a test background. Comparing the tunneling probability obtained with the Boltzmann formula, we succeed in reading the standard Hawking temperature of the dyonic Reissner–Nordström black hole.

  10. Binary Black Hole Mergers from Globular Clusters: Masses, Merger Rates, and the Impact of Stellar Evolution

    CERN Document Server

    Rodriguez, Carl L; Rasio, Frederic A

    2016-01-01

    Expanding upon our previous work (Rodriguez et al., 2015), we study merging binary black holes formed in globular clusters using our Monte Carlo approach to stellar dynamics. We have created a new set of 52 cluster models with different masses, metallicities, and radii to fully characterize the binary black hole merger rate. These models include all the relevant dynamical processes (such as two-body relaxation, strong encounters, and three-body binary formation) and agree well with detailed direct N-body simulations. In addition, we have enhanced our stellar evolution algorithms with updated metallicity-dependent stellar wind and supernova prescriptions, allowing us to compare our results directly to the most recent population synthesis predictions for merger rates from isolated binary evolution. We explore the relationship between a cluster's global properties and the population of binary black holes that it produces. In particular, we derive a numerically calibrated relationship between the merger times of ...

  11. The physics of the relativistic counter-streaming instability that drives mass inflation inside black holes

    CERN Document Server

    Hamilton, Andrew J S

    2008-01-01

    If you fall into a real astronomical black hole (choosing a supermassive black hole, to make sure that the tidal forces don't get you first), then you will probably meet your fate not at a central singularity, but rather in the exponentially growing, relativistic counter-streaming instability at the inner horizon first pointed out by Poisson & Israel (1990), who called it mass inflation. The purpose of this paper is to present a clear exposition of the physical cause and consequence of inflation in spherical, charged black holes. Inflation acts like a particle accelerator in that it accelerates cold ingoing and outgoing streams through each other to prodigiously high energies. Inflation feeds on itself: the acceleration is powered by the gravity produced by the streaming energy.

  12. Black holes and beyond

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-02-01

    Belief in the existence of black holes is the ultimate act of faith for a physicist. First suggested by the English clergyman John Michell in the year 1784, the gravitational pull of a black hole is so strong that nothing - not even light - can escape. Gravity might be the weakest of the fundamental forces but black-hole physics is not for the faint-hearted. Black holes present obvious problems for would-be observers because they cannot, by definition, be seen with conventional telescopes - although before the end of the decade gravitational-wave detectors should be able to study collisions between black holes. Until then astronomers can only infer the existence of a black hole from its gravitational influence on other matter, or from the X-rays emitted by gas and dust as they are dragged into the black hole. However, once this material passes through the 'event horizon' that surrounds the black hole, we will never see it again - not even with X-ray specs. Despite these observational problems, most physicists and astronomers believe that black holes do exist. Small black holes a few kilometres across are thought to form when stars weighing more than about two solar masses collapse under the weight of their own gravity, while supermassive black holes weighing millions of solar masses appear to be present at the centre of most galaxies. Moreover, some brave physicists have proposed ways to make black holes - or at least event horizons - in the laboratory. The basic idea behind these 'artificial black holes' is not to compress a large amount of mass into a small volume, but to reduce the speed of light in a moving medium to less than the speed of the medium and so create an event horizon. The parallels with real black holes are not exact but the experiments could shed new light on a variety of phenomena. The first challenge, however, is to get money for the research. One year on from a high-profile meeting on artificial black holes in London, for

  13. Exploring the unusually high black hole-to-bulge mass ratios in NGC4342 and NGC4291: the asynchronous growth of bulges and black holes

    CERN Document Server

    Bogdan, Akos; Zhuravleva, Irina; Mihos, J Christopher; Kraft, Ralph P; Harding, Paul; Guo, Qi; Li, Zhiyuan; Churazov, Eugene; Vikhlinin, Alexey; Nulsen, Paul E J; Schindler, Sabine; Jones, Christine

    2012-01-01

    We study two nearby, early-type galaxies, NGC4342 and NGC4291, that host unusually massive black holes relative to their low stellar mass. The observed black hole-to-bulge mass ratios of NGC4342 and NGC4291 are ~6.9% and ~1.9%, respectively, which significantly exceed the typical observed ratio of ~0.2%. As a consequence of the exceedingly large black hole-to-bulge mass ratios, NGC4342 and NGC4291 are ~5.1 sigma and ~3.4 sigma outliers from the M_BH - M_bulge scaling relation, respectively. In this paper we explore the origin of the unusually high black hole-to-bulge mass ratio. Based on Chandra X-ray observations of the hot gas content of NGC4342 and NGC4291, we compute gravitating mass profiles, and conclude that both galaxies reside in massive dark matter halos, which extend well beyond the stellar light. The presence of dark matter halos around NGC4342 and NGC4291 and a deep optical image of the environment of NGC4342 indicate that tidal stripping, in which >90% of the stellar mass was lost, cannot explai...

  14. A stellar-mass black hole population in the globular cluster NGC 6101?

    CERN Document Server

    Peuten, Miklos; Gieles, Mark; Gualandris, Alessia; Henault-Brunet, Vincent

    2016-01-01

    Dalessandro et al. observed a similar distribution for blue straggler stars and main-sequence turn-off stars in the Galactic globular cluster NGC 6101, and interpreted this feature as an indication that this cluster is not mass-segregated. Using direct N-body simulations, we find that a significant amount of mass segregation is expected for a cluster with the mass, radius and age of NGC 6101. Therefore, the absence of mass segregation cannot be explained by the argument that the cluster is not yet dynamically evolved. By varying the retention fraction of stellar-mass black holes, we show that segregation is not observable in clusters with a high black hole retention fraction (>50% after supernova kicks and >50% after dynamical evolution). Yet all model clusters have the same amount of mass segregation in terms of the decline of the mean mass of stars and remnants with distance to the centre. We also discuss how kinematics can be used to further constrain the presence of a stellar-mass black hole population an...

  15. Prospects for measuring supermassive black hole masses with future extremely large telescopes

    CERN Document Server

    Do, Tuan; Barth, Aaron J; Barton, Elizabeth J; Simard, Luc; Larkin, James E; Moore, Anna M; Wang, Lianqi; Ellerbroek, Brent

    2014-01-01

    The next generation of giant-segmented mirror telescopes ($>$ 20 m) will enable us to observe galactic nuclei at much higher angular resolution and sensitivity than ever before. These capabilities will introduce a revolutionary shift in our understanding of the origin and evolution of supermassive black holes by enabling more precise black hole mass measurements in a mass range that is unreachable today. We present simulations and predictions of the observations of nuclei that will be made with the Thirty Meter Telescope (TMT) and the adaptive optics assisted integral-field spectrograph IRIS, which is capable of diffraction-limited spectroscopy from $Z$ band (0.9 $\\mu$m) to $K$ band (2.2 $\\mu$m). These simulations, for the first time, use realistic values for the sky, telescope, adaptive optics system, and instrument, to determine the expected signal-to-noise ratio of a range of possible targets spanning intermediate mass black holes of $\\sim10^4$ \\msun to the most massive black holes known today of $>10^{10}...

  16. Investigating the AGN activity and black hole masses in Low Surface brightness galaxies

    CERN Document Server

    Subramanian., Smitha; Das., Mousumi; George., Koshy; Sivarani, T; Prabhu, T P

    2015-01-01

    We present an analysis of the optical nuclear spectra from the active galactic nuclei (AGN) in a sample of giant low surface brightness (GLSB) galaxies. GLSB galaxies are extreme late type spirals that are large, isolated and poorly evolved compared to regular spiral galaxies. Earlier studies have indicated that their nuclei have relatively low mass black holes. Using data from the Sloan Digital Sky Survey (SDSS), we selected a sample of 30 GLSB galaxies that showed broad H$\\alpha$ emission lines in their AGN spectra. In some galaxies such as UGC 6284, the broad component of H$\\alpha$ is more related to outflows rather than the black hole. One galaxy (UGC 6614) showed two broad components in H$\\alpha$, one associated with the black hole and the other associated with an outflow event. We derived the nuclear black hole (BH) masses of 29 galaxies from their broad H$\\alpha$ parameters. We find that the nuclear BH masses lie in the range $10^{5}-10^{7} M_{\\odot}$. The bulge stellar velocity dispersion $\\sigma_{e}$...

  17. GW151226: Observation of Gravitational Waves from a 22-Solar-Mass Binary Black Hole Coalescence

    Science.gov (United States)

    Abbott, B. P.; Abbott, R.; Abbott, T. D.; Abernathy, M. R.; Acernese, F.; Ackley, K.; Adams, C.; Adams, T.; Addesso, P.; Adhikari, R. X.; Adya, V. B.; Affeldt, C.; Agathos, M.; Agatsuma, K.; Aggarwal, N.; Aguiar, O. D.; Aiello, L.; Ain, A.; Ajith, P.; Allen, B.; Allocca, A.; Altin, P. A.; Anderson, S. B.; Anderson, W. G.; Arai, K.; Araya, M. C.; Arceneaux, C. C.; Areeda, J. S.; Arnaud, N.; Arun, K. G.; Ascenzi, S.; Ashton, G.; Ast, M.; Aston, S. M.; Astone, P.; Aufmuth, P.; Aulbert, C.; Babak, S.; Bacon, P.; Bader, M. K. M.; Baker, P. T.; Baldaccini, F.; Ballardin, G.; Ballmer, S. W.; Barayoga, J. C.; Barclay, S. E.; Barish, B. C.; Barker, D.; Barone, F.; Barr, B.; Barsotti, L.; Barsuglia, M.; Barta, D.; Bartlett, J.; Bartos, I.; Bassiri, R.; Basti, A.; Batch, J. C.; Baune, C.; Bavigadda, V.; Bazzan, M.; Bejger, M.; Bell, A. S.; Berger, B. K.; Bergmann, G.; Berry, C. P. L.; Bersanetti, D.; Bertolini, A.; Betzwieser, J.; Bhagwat, S.; Bhandare, R.; Bilenko, I. A.; Billingsley, G.; Birch, J.; Birney, R.; Birnholtz, O.; Biscans, S.; Bisht, A.; Bitossi, M.; Biwer, C.; Bizouard, M. A.; Blackburn, J. K.; Blair, C. D.; Blair, D. G.; Blair, R. M.; Bloemen, S.; Bock, O.; Boer, M.; Bogaert, G.; Bogan, C.; Bohe, A.; Bond, C.; Bondu, F.; Bonnand, R.; Boom, B. A.; Bork, R.; Boschi, V.; Bose, S.; Bouffanais, Y.; Bozzi, A.; Bradaschia, C.; Brady, P. R.; Braginsky, V. B.; Branchesi, M.; Brau, J. E.; Briant, T.; Brillet, A.; Brinkmann, M.; Brisson, V.; Brockill, P.; Broida, J. E.; Brooks, A. F.; Brown, D. A.; Brown, D. D.; Brown, N. M.; Brunett, S.; Buchanan, C. C.; Buikema, A.; Bulik, T.; Bulten, H. J.; Buonanno, A.; Buskulic, D.; Buy, C.; Byer, R. L.; Cabero, M.; Cadonati, L.; Cagnoli, G.; Cahillane, C.; Calderón Bustillo, J.; Callister, T.; Calloni, E.; Camp, J. B.; Cannon, K. C.; Cao, J.; Capano, C. D.; Capocasa, E.; Carbognani, F.; Caride, S.; Casanueva Diaz, J.; Casentini, C.; Caudill, S.; Cavaglià, M.; Cavalier, F.; Cavalieri, R.; Cella, G.; Cepeda, C. B.; Cerboni Baiardi, L.; Cerretani, G.; Cesarini, E.; Chamberlin, S. J.; Chan, M.; Chao, S.; Charlton, P.; Chassande-Mottin, E.; Cheeseboro, B. D.; Chen, H. Y.; Chen, Y.; Cheng, C.; Chincarini, A.; Chiummo, A.; Cho, H. S.; Cho, M.; Chow, J. H.; Christensen, N.; Chu, Q.; Chua, S.; Chung, S.; Ciani, G.; Clara, F.; Clark, J. A.; Cleva, F.; Coccia, E.; Cohadon, P.-F.; Colla, A.; Collette, C. G.; Cominsky, L.; Constancio, M.; Conte, A.; Conti, L.; Cook, D.; Corbitt, T. R.; Cornish, N.; Corsi, A.; Cortese, S.; Costa, C. A.; Coughlin, M. W.; Coughlin, S. B.; Coulon, J.-P.; Countryman, S. T.; Couvares, P.; Cowan, E. E.; Coward, D. M.; Cowart, M. J.; Coyne, D. C.; Coyne, R.; Craig, K.; Creighton, J. D. E.; Cripe, J.; Crowder, S. G.; Cumming, A.; Cunningham, L.; Cuoco, E.; Dal Canton, T.; Danilishin, S. L.; D'Antonio, S.; Danzmann, K.; Darman, N. S.; Dasgupta, A.; Da Silva Costa, C. F.; Dattilo, V.; Dave, I.; Davier, M.; Davies, G. S.; Daw, E. J.; Day, R.; De, S.; DeBra, D.; Debreczeni, G.; Degallaix, J.; De Laurentis, M.; Deléglise, S.; Del Pozzo, W.; Denker, T.; Dent, T.; Dergachev, V.; De Rosa, R.; DeRosa, R. T.; DeSalvo, R.; Devine, R. C.; Dhurandhar, S.; Díaz, M. C.; Di Fiore, L.; Di Giovanni, M.; Di Girolamo, T.; Di Lieto, A.; Di Pace, S.; Di Palma, I.; Di Virgilio, A.; Dolique, V.; Donovan, F.; Dooley, K. L.; Doravari, S.; Douglas, R.; Downes, T. P.; Drago, M.; Drever, R. W. P.; Driggers, J. C.; Ducrot, M.; Dwyer, S. E.; Edo, T. B.; Edwards, M. C.; Effler, A.; Eggenstein, H.-B.; Ehrens, P.; Eichholz, J.; Eikenberry, S. S.; Engels, W.; Essick, R. C.; Etzel, T.; Evans, M.; Evans, T. M.; Everett, R.; Factourovich, M.; Fafone, V.; Fair, H.; Fairhurst, S.; Fan, X.; Fang, Q.; Farinon, S.; Farr, B.; Farr, W. M.; Favata, M.; Fays, M.; Fehrmann, H.; Fejer, M. M.; Fenyvesi, E.; Ferrante, I.; Ferreira, E. C.; Ferrini, F.; Fidecaro, F.; Fiori, I.; Fiorucci, D.; Fisher, R. P.; Flaminio, R.; Fletcher, M.; Fong, H.; Fournier, J.-D.; Frasca, S.; Frasconi, F.; Frei, Z.; Freise, A.; Frey, R.; Frey, V.; Fritschel, P.; Frolov, V. V.; Fulda, P.; Fyffe, M.; Gabbard, H. A. G.; Gair, J. R.; Gammaitoni, L.; Gaonkar, S. G.; Garufi, F.; Gaur, G.; Gehrels, N.; Gemme, G.; Geng, P.; Genin, E.; Gennai, A.; George, J.; Gergely, L.; Germain, V.; Ghosh, Abhirup; Ghosh, Archisman; Ghosh, S.; Giaime, J. A.; Giardina, K. D.; Giazotto, A.; Gill, K.; Glaefke, A.; Goetz, E.; Goetz, R.; Gondan, L.; González, G.; Gonzalez Castro, J. M.; Gopakumar, A.; Gordon, N. A.; Gorodetsky, M. L.; Gossan, S. E.; Gosselin, M.; Gouaty, R.; Grado, A.; Graef, C.; Graff, P. B.; Granata, M.; Grant, A.; Gras, S.; Gray, C.; Greco, G.; Green, A. C.; Groot, P.; Grote, H.; Grunewald, S.; Guidi, G. M.; Guo, X.; Gupta, A.; Gupta, M. K.; Gushwa, K. E.; Gustafson, E. K.; Gustafson, R.; Hacker, J. J.; Hall, B. R.; Hall, E. D.; Hamilton, H.; Hammond, G.; Haney, M.; Hanke, M. M.; Hanks, J.; Hanna, C.; Hannam, M. D.; Hanson, J.; Hardwick, T.; Harms, J.; Harry, G. M.; Harry, I. W.; Hart, M. J.; Hartman, M. T.; Haster, C.-J.; Haughian, K.; Healy, J.; Heidmann, A.; Heintze, M. C.; Heitmann, H.; Hello, P.; Hemming, G.; Hendry, M.; Heng, I. S.; Hennig, J.; Henry, J.; Heptonstall, A. W.; Heurs, M.; Hild, S.; Hoak, D.; Hofman, D.; Holt, K.; Holz, D. E.; Hopkins, P.; Hough, J.; Houston, E. A.; Howell, E. J.; Hu, Y. M.; Huang, S.; Huerta, E. A.; Huet, D.; Hughey, B.; Husa, S.; Huttner, S. H.; Huynh-Dinh, T.; Indik, N.; Ingram, D. R.; Inta, R.; Isa, H. N.; Isac, J.-M.; Isi, M.; Isogai, T.; Iyer, B. R.; Izumi, K.; Jacqmin, T.; Jang, H.; Jani, K.; Jaranowski, P.; Jawahar, S.; Jian, L.; Jiménez-Forteza, F.; Johnson, W. W.; Johnson-McDaniel, N. K.; Jones, D. I.; Jones, R.; Jonker, R. J. G.; Ju, L.; K, Haris; Kalaghatgi, C. V.; Kalogera, V.; Kandhasamy, S.; Kang, G.; Kanner, J. B.; Kapadia, S. J.; Karki, S.; Karvinen, K. S.; Kasprzack, M.; Katsavounidis, E.; Katzman, W.; Kaufer, S.; Kaur, T.; Kawabe, K.; Kéfélian, F.; Kehl, M. S.; Keitel, D.; Kelley, D. B.; Kells, W.; Kennedy, R.; Key, J. S.; Khalili, F. Y.; Khan, I.; Khan, S.; Khan, Z.; Khazanov, E. A.; Kijbunchoo, N.; Kim, Chi-Woong; Kim, Chunglee; Kim, J.; Kim, K.; Kim, N.; Kim, W.; Kim, Y.-M.; Kimbrell, S. J.; King, E. J.; King, P. J.; Kissel, J. S.; Klein, B.; Kleybolte, L.; Klimenko, S.; Koehlenbeck, S. M.; Koley, S.; Kondrashov, V.; Kontos, A.; Korobko, M.; Korth, W. Z.; Kowalska, I.; Kozak, D. B.; Kringel, V.; Krishnan, B.; Królak, A.; Krueger, C.; Kuehn, G.; Kumar, P.; Kumar, R.; Kuo, L.; Kutynia, A.; Lackey, B. D.; Landry, M.; Lange, J.; Lantz, B.; Lasky, P. D.; Laxen, M.; Lazzarini, A.; Lazzaro, C.; Leaci, P.; Leavey, S.; Lebigot, E. O.; Lee, C. H.; Lee, H. K.; Lee, H. M.; Lee, K.; Lenon, A.; Leonardi, M.; Leong, J. R.; Leroy, N.; Letendre, N.; Levin, Y.; Lewis, J. B.; Li, T. G. F.; Libson, A.; Littenberg, T. B.; Lockerbie, N. A.; Lombardi, A. L.; London, L. T.; Lord, J. E.; Lorenzini, M.; Loriette, V.; Lormand, M.; Losurdo, G.; Lough, J. D.; Lousto, C. O.; Lück, H.; Lundgren, A. P.; Lynch, R.; Ma, Y.; Machenschalk, B.; MacInnis, M.; Macleod, D. M.; Magaña-Sandoval, F.; Magaña Zertuche, L.; Magee, R. M.; Majorana, E.; Maksimovic, I.; Malvezzi, V.; Man, N.; Mandel, I.; Mandic, V.; Mangano, V.; Mansell, G. L.; Manske, M.; Mantovani, M.; Marchesoni, F.; Marion, F.; Márka, S.; Márka, Z.; Markosyan, A. S.; Maros, E.; Martelli, F.; Martellini, L.; Martin, I. W.; Martynov, D. V.; Marx, J. N.; Mason, K.; Masserot, A.; Massinger, T. J.; Masso-Reid, M.; Mastrogiovanni, S.; Matichard, F.; Matone, L.; Mavalvala, N.; Mazumder, N.; McCarthy, R.; McClelland, D. E.; McCormick, S.; McGuire, S. C.; McIntyre, G.; McIver, J.; McManus, D. J.; McRae, T.; McWilliams, S. T.; Meacher, D.; Meadors, G. D.; Meidam, J.; Melatos, A.; Mendell, G.; Mercer, R. A.; Merilh, E. L.; Merzougui, M.; Meshkov, S.; Messenger, C.; Messick, C.; Metzdorff, R.; Meyers, P. M.; Mezzani, F.; Miao, H.; Michel, C.; Middleton, H.; Mikhailov, E. E.; Milano, L.; Miller, A. L.; Miller, A.; Miller, B. B.; Miller, J.; Millhouse, M.; Minenkov, Y.; Ming, J.; Mirshekari, S.; Mishra, C.; Mitra, S.; Mitrofanov, V. P.; Mitselmakher, G.; Mittleman, R.; Moggi, A.; Mohan, M.; Mohapatra, S. R. P.; Montani, M.; Moore, B. C.; Moore, C. J.; Moraru, D.; Moreno, G.; Morriss, S. R.; Mossavi, K.; Mours, B.; Mow-Lowry, C. M.; Mueller, G.; Muir, A. W.; Mukherjee, Arunava; Mukherjee, D.; Mukherjee, S.; Mukund, N.; Mullavey, A.; Munch, J.; Murphy, D. J.; Murray, P. G.; Mytidis, A.; Nardecchia, I.; Naticchioni, L.; Nayak, R. K.; Nedkova, K.; Nelemans, G.; Nelson, T. J. N.; Neri, M.; Neunzert, A.; Newton, G.; Nguyen, T. T.; Nielsen, A. B.; Nissanke, S.; Nitz, A.; Nocera, F.; Nolting, D.; Normandin, M. E. N.; Nuttall, L. K.; Oberling, J.; Ochsner, E.; O'Dell, J.; Oelker, E.; Ogin, G. H.; Oh, J. J.; Oh, S. H.; Ohme, F.; Oliver, M.; Oppermann, P.; Oram, Richard J.; O'Reilly, B.; O'Shaughnessy, R.; Ottaway, D. J.; Overmier, H.; Owen, B. J.; Pai, A.; Pai, S. A.; Palamos, J. R.; Palashov, O.; Palomba, C.; Pal-Singh, A.; Pan, H.; Pankow, C.; Pannarale, F.; Pant, B. C.; Paoletti, F.; Paoli, A.; Papa, M. A.; Paris, H. R.; Parker, W.; Pascucci, D.; Pasqualetti, A.; Passaquieti, R.; Passuello, D.; Patricelli, B.; Patrick, Z.; Pearlstone, B. L.; Pedraza, M.; Pedurand, R.; Pekowsky, L.; Pele, A.; Penn, S.; Perreca, A.; Perri, L. M.; Pfeiffer, H. P.; Phelps, M.; Piccinni, O. J.; Pichot, M.; Piergiovanni, F.; Pierro, V.; Pillant, G.; Pinard, L.; Pinto, I. M.; Pitkin, M.; Poe, M.; Poggiani, R.; Popolizio, P.; Post, A.; Powell, J.; Prasad, J.; Predoi, V.; Prestegard, T.; Price, L. R.; Prijatelj, M.; Principe, M.; Privitera, S.; Prix, R.; Prodi, G. A.; Prokhorov, L.; Puncken, O.; Punturo, M.; Puppo, P.; Pürrer, M.; Qi, H.; Qin, J.; Qiu, S.; Quetschke, V.; Quintero, E. A.; Quitzow-James, R.; Raab, F. J.; Rabeling, D. S.; Radkins, H.; Raffai, P.; Raja, S.; Rajan, C.; Rakhmanov, M.; Rapagnani, P.; Raymond, V.; Razzano, M.; Re, V.; Read, J.; Reed, C. M.; Regimbau, T.; Rei, L.; Reid, S.; Reitze, D. H.; Rew, H.; Reyes, S. D.; Ricci, F.; Riles, K.; Rizzo, M.; Robertson, N. A.; Robie, R.; Robinet, F.; Rocchi, A.; Rolland, L.; Rollins, J. G.; Roma, V. J.; Romano, J. D.; Romano, R.; Romanov, G.; Romie, J. H.; Rosińska, D.; Rowan, S.; Rüdiger, A.; Ruggi, P.; Ryan, K.; Sachdev, S.; Sadecki, T.; Sadeghian, L.; Sakellariadou, M.; Salconi, L.; Saleem, M.; Salemi, F.; Samajdar, A.; Sammut, L.; Sanchez, E. J.; Sandberg, V.; Sandeen, B.; Sanders, J. R.; Sassolas, B.; Sathyaprakash, B. S.; Saulson, P. R.; Sauter, O. E. S.; Savage, R. L.; Sawadsky, A.; Schale, P.; Schilling, R.; Schmidt, J.; Schmidt, P.; Schnabel, R.; Schofield, R. M. S.; Schönbeck, A.; Schreiber, E.; Schuette, D.; Schutz, B. F.; Scott, J.; Scott, S. M.; Sellers, D.; Sengupta, A. S.; Sentenac, D.; Sequino, V.; Sergeev, A.; Setyawati, Y.; Shaddock, D. A.; Shaffer, T.; Shahriar, M. S.; Shaltev, M.; Shapiro, B.; Shawhan, P.; Sheperd, A.; Shoemaker, D. H.; Shoemaker, D. M.; Siellez, K.; Siemens, X.; Sieniawska, M.; Sigg, D.; Silva, A. D.; Singer, A.; Singer, L. P.; Singh, A.; Singh, R.; Singhal, A.; Sintes, A. M.; Slagmolen, B. J. J.; Smith, J. R.; Smith, N. D.; Smith, R. J. E.; Son, E. J.; Sorazu, B.; Sorrentino, F.; Souradeep, T.; Srivastava, A. K.; Staley, A.; Steinke, M.; Steinlechner, J.; Steinlechner, S.; Steinmeyer, D.; Stephens, B. C.; Stevenson, S. P.; Stone, R.; Strain, K. A.; Straniero, N.; Stratta, G.; Strauss, N. A.; Strigin, S.; Sturani, R.; Stuver, A. L.; Summerscales, T. Z.; Sun, L.; Sunil, S.; Sutton, P. J.; Swinkels, B. L.; Szczepańczyk, M. J.; Tacca, M.; Talukder, D.; Tanner, D. B.; Tápai, M.; Tarabrin, S. P.; Taracchini, A.; Taylor, R.; Theeg, T.; Thirugnanasambandam, M. P.; Thomas, E. G.; Thomas, M.; Thomas, P.; Thorne, K. A.; Thrane, E.; Tiwari, S.; Tiwari, V.; Tokmakov, K. V.; Toland, K.; Tomlinson, C.; Tonelli, M.; Tornasi, Z.; Torres, C. V.; Torrie, C. I.; Töyrä, D.; Travasso, F.; Traylor, G.; Trifirò, D.; Tringali, M. C.; Trozzo, L.; Tse, M.; Turconi, M.; Tuyenbayev, D.; Ugolini, D.; Unnikrishnan, C. S.; Urban, A. L.; Usman, S. A.; Vahlbruch, H.; Vajente, G.; Valdes, G.; Vallisneri, M.; van Bakel, N.; van Beuzekom, M.; van den Brand, J. F. J.; Van Den Broeck, C.; Vander-Hyde, D. C.; van der Schaaf, L.; van Heijningen, J. V.; van Veggel, A. A.; Vardaro, M.; Vass, S.; Vasúth, M.; Vaulin, R.; Vecchio, A.; Vedovato, G.; Veitch, J.; Veitch, P. J.; Venkateswara, K.; Verkindt, D.; Vetrano, F.; Viceré, A.; Vinciguerra, S.; Vine, D. J.; Vinet, J.-Y.; Vitale, S.; Vo, T.; Vocca, H.; Vorvick, C.; Voss, D. V.; Vousden, W. D.; Vyatchanin, S. P.; Wade, A. R.; Wade, L. E.; Wade, M.; Walker, M.; Wallace, L.; Walsh, S.; Wang, G.; Wang, H.; Wang, M.; Wang, X.; Wang, Y.; Ward, R. L.; Warner, J.; Was, M.; Weaver, B.; Wei, L.-W.; Weinert, M.; Weinstein, A. J.; Weiss, R.; Wen, L.; Weßels, P.; Westphal, T.; Wette, K.; Whelan, J. T.; Whiting, B. F.; Williams, R. D.; Williamson, A. R.; Willis, J. L.; Willke, B.; Wimmer, M. H.; Winkler, W.; Wipf, C. C.; Wittel, H.; Woan, G.; Woehler, J.; Worden, J.; Wright, J. L.; Wu, D. S.; Wu, G.; Yablon, J.; Yam, W.; Yamamoto, H.; Yancey, C. C.; Yu, H.; Yvert, M.; ZadroŻny, A.; Zangrando, L.; Zanolin, M.; Zendri, J.-P.; Zevin, M.; Zhang, L.; Zhang, M.; Zhang, Y.; Zhao, C.; Zhou, M.; Zhou, Z.; Zhu, X. J.; Zucker, M. E.; Zuraw, S. E.; Zweizig, J.; Boyle, M.; Hemberger, D.; Kidder, L. E.; Lovelace, G.; Ossokine, S.; Scheel, M.; Szilagyi, B.; Teukolsky, S.; LIGO Scientific Collaboration; Virgo Collaboration

    2016-06-01

    We report the observation of a gravitational-wave signal produced by the coalescence of two stellar-mass black holes. The signal, GW151226, was observed by the twin detectors of the Laser Interferometer Gravitational-Wave Observatory (LIGO) on December 26, 2015 at 03:38:53 UTC. The signal was initially identified within 70 s by an online matched-filter search targeting binary coalescences. Subsequent off-line analyses recovered GW151226 with a network signal-to-noise ratio of 13 and a significance greater than 5 σ . The signal persisted in the LIGO frequency band for approximately 1 s, increasing in frequency and amplitude over about 55 cycles from 35 to 450 Hz, and reached a peak gravitational strain of 3. 4-0.9+0.7×10-22 . The inferred source-frame initial black hole masses are 14.2-3.7+8.3 M⊙ and 7. 5-2.3+2.3 M⊙, and the final black hole mass is 20.8-1.7+6.1 M⊙. We find that at least one of the component black holes has spin greater than 0.2. This source is located at a luminosity distance of 44 0-190+180 Mpc corresponding to a redshift of 0.0 9-0.04+0.03. All uncertainties define a 90% credible interval. This second gravitational-wave observation provides improved constraints on stellar populations and on deviations from general relativity.

  18. GW151226: Observation of Gravitational Waves from a 22-Solar-Mass Binary Black Hole Coalescence

    CERN Document Server

    ,

    2016-01-01

    We report the observation of a gravitational-wave signal produced by the coalescence of two stellar-mass black holes. The signal, GW151226, was observed by the twin detectors of the Laser Interferometer Gravitational-Wave Observatory (LIGO) on December 26, 2015 at 03:38:53 UTC. The signal was initially identified within 70 s by an online matched-filter search targeting binary coalescences. Subsequent off-line analyses recovered GW151226 with a network signal-to-noise ratio of 13 and a significance greater than 5 $\\sigma$. The signal persisted in the LIGO frequency band for approximately 1 s, increasing in frequency and amplitude over about 55 cycles from 35 to 450 Hz, and reached a peak gravitational strain of $3.4_{-0.9}^{+0.7} \\times 10^{-22}$. The inferred source-frame initial black hole masses are $14.2_{-3.7}^{+8.3} M_{\\odot}$ and $7.5_{-2.3}^{+2.3} M_{\\odot}$ and the final black hole mass is $20.8_{-1.7}^{+6.1} M_{\\odot}$. We find that at least one of the component black holes has spin greater than 0.2....

  19. CIV Emission Line Properties and Systematic Trends in Quasar Black Hole Mass Estimates

    CERN Document Server

    Coatman, Liam; Banerji, Manda; Richards, Gordon T

    2016-01-01

    Black-hole masses are crucial to understanding the physics of the connection between quasars and their host galaxies and measuring cosmic black hole-growth. At high redshift, z > 2.1, black hole masses are normally derived using the velocity-width of the CIV broad emission line, based on the assumption that the observed velocity-widths arise from virial-induced motions. In many quasars, the CIV-emission line exhibits significant blue asymmetries (`blueshifts') with the line centroid displaced by up to thousands of km/s to the blue. These blueshifts almost certainly signal the presence of strong outflows, most likely originating in a disc wind. We have obtained near-infrared spectra, including the H$\\alpha$ emission line, for 19 luminous ($L_{Bol}$ = 46.5-47.5 erg/s) Sloan Digital Sky Survey quasars, at redshifts 2 2000 km/s, the velocity-widths appear to be dominated by non-virial motions. Black-hole masses, based on the full width at half maximum of the CIV-emission line, can be overestimated by a factor of...

  20. Empirical Constraints on the Evolution of the Relationship between Black Hole and Galaxy Mass: Scatter Matters

    OpenAIRE

    Somerville, Rachel S.

    2009-01-01

    I investigate whether useful constraints on the evolution of the relationship between galaxy mass and black hole (BH) mass can be obtained from recent measurements of galaxy stellar mass functions and QSO bolometric luminosity functions at high redshift. I assume a simple power-law relationship between galaxy mass and BH mass, as implied by BH mass measurements at low redshift, and consider only evolution in the zero-point of the relation. I argue that one can obtain a lower limit on the zero...

  1. Synchrotron peak luminosity,black hole mass and Eddington ratio for SDSS flat-spectrum radio quasars

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    For a sample of 185 flat-spectrum radio quasars(FSRQs) constructed from the SDSS DR3 quasar catalog,we found a significant correlation between the synchrotron peak luminosity and both the black hole mass and Eddington ratio.This implies that the physics of its jet formation is not only tightly related with the black hole mass,but also with the accretion rate.We verify that the synchrotron peak luminosity can be a better indicator of jet emission than 5 GHz luminosity,through comparing the relationships between each of these two parameters and both black hole mass and Eddington ratio.The fundamental plane of black hole activity for our FSRQs is established as Lr ∝ L0x.80 ± 0.06 Mbh -0.04 ± 0.09 with a weak dependence on black hole mass,however,the scatter is significant.

  2. Unification of the Fundamental Plane and Super-Massive Black Holes Masses

    CERN Document Server

    Bosch, Remco van den

    2016-01-01

    According to the Virial Theorem, all gravitational systems in equilibrium sit on a plane in the 3D parameter space defined by their mass, size and second moment of the velocity tensor. While these quantities cannot be directly observed, there are suitable proxies: the luminosity Lk, half-light radius Re and dispersion sigma_e. These proxies indeed lie on a very tight Fundamental Plane (FP). How do the black holes in the centers of galaxies relate to the FP? Their masses are known to exhibit no strong correlation with total galaxy mass, but they do correlate weakly with bulge mass (when present), and extremely well with the velocity dispersion through the Mbh = sigma_e^5.3 relation. These facts together imply that a tight plane must also exist defined by black hole mass, total galaxy mass and size. Here I show that this is indeed the case using a heterogeneous set of 225 black holes. The sample includes BHs from zero to 10 billion solar masses and host galaxies ranging from low surface brightness dwarfs, throu...

  3. A mass estimate of an intermediate-mass black hole in omega Centauri

    CERN Document Server

    Miocchi, P

    2010-01-01

    Context. The problem of the existence of intermediate-mass black holes (IMBHs) at the centre of globular clusters is a hot and controversial topic in current astrophysical research with important implications in stellar and galaxy formation. Aims. In this paper, we aim at giving further support to the presence of an IMBH in omega Centauri and at providing an independent estimate of its mass. Methods. We employed a self-consistent spherical model with anisotropic velocity distribution. It consists in a generalisation of the King model by including the Bahcall-Wolf distribution function in the IMBH vicinity. Results. By the parametric fitting of the model to recent HST/ACS data for the surface brightness profile, we found an IMBH to cluster total mass ratio of M_BH/M = 5.8(+0.9-1.2) x 10^(-3). It is also found that the model yields a fit of the line-of-sight velocity dispersion profile that is better without mass segregation than in the segregated case. This confirms the current thought of a non-relaxed status ...

  4. Black holes and the multiverse

    Science.gov (United States)

    Garriga, Jaume; Vilenkin, Alexander; Zhang, Jun

    2016-02-01

    Vacuum bubbles may nucleate and expand during the inflationary epoch in the early universe. After inflation ends, the bubbles quickly dissipate their kinetic energy; they come to rest with respect to the Hubble flow and eventually form black holes. The fate of the bubble itself depends on the resulting black hole mass. If the mass is smaller than a certain critical value, the bubble collapses to a singularity. Otherwise, the bubble interior inflates, forming a baby universe, which is connected to the exterior FRW region by a wormhole. A similar black hole formation mechanism operates for spherical domain walls nucleating during inflation. As an illustrative example, we studied the black hole mass spectrum in the domain wall scenario, assuming that domain walls interact with matter only gravitationally. Our results indicate that, depending on the model parameters, black holes produced in this scenario can have significant astrophysical effects and can even serve as dark matter or as seeds for supermassive black holes. The mechanism of black hole formation described in this paper is very generic and has important implications for the global structure of the universe. Baby universes inside super-critical black holes inflate eternally and nucleate bubbles of all vacua allowed by the underlying particle physics. The resulting multiverse has a very non-trivial spacetime structure, with a multitude of eternally inflating regions connected by wormholes. If a black hole population with the predicted mass spectrum is discovered, it could be regarded as evidence for inflation and for the existence of a multiverse.

  5. Characterizing Black Hole Mergers

    Science.gov (United States)

    Baker, John; Boggs, William Darian; Kelly, Bernard

    2010-01-01

    Binary black hole mergers are a promising source of gravitational waves for interferometric gravitational wave detectors. Recent advances in numerical relativity have revealed the predictions of General Relativity for the strong burst of radiation generated in the final moments of binary coalescence. We explore features in the merger radiation which characterize the final moments of merger and ringdown. Interpreting the waveforms in terms of an rotating implicit radiation source allows a unified phenomenological description of the system from inspiral through ringdown. Common features in the waveforms allow quantitative description of the merger signal which may provide insights for observations large-mass black hole binaries.

  6. How objective is black hole entropy?

    CERN Document Server

    Lau, Y K

    1994-01-01

    The objectivity of black hole entropy is discussed in the particular case of a Schwarzchild black hole. Using Jaynes' maximum entropy formalism and Euclidean path integral evaluation of partition function, it is argued that in the semiclassical limit when the fluctutation of metric is neglected, the black hole entropy of a Schwarzchild black hole is equal to the maximal information entropy of an observer whose sole knowledge of the black hole is its mass. Black hole entropy becomes a measure of number of its internal mass eigenstates in accordance with the Boltzmann principle only in the limit of negligible relative mass fluctutation. {}From the information theoretic perspective, the example of a Schwarzchild black hole seems to suggest that black hole entropy is no different from ordinary thermodynamic entropy. It is a property of the experimental data of a black hole, rather than being an intrinsic physical property of a black hole itself independent of any observer. However, it is still weakly objective in...

  7. A 17-billion-solar-mass black hole in a group galaxy with a diffuse core

    CERN Document Server

    Thomas, Jens; McConnell, Nicholas J; Greene, Jenny E; Blakeslee, John P; Janish, Ryan

    2016-01-01

    Quasars are associated with and powered by the accretion of material onto massive black holes; the detection of highly luminous quasars with redshifts greater than z = 6 suggests that black holes of up to ten billion solar masses already existed 13 billion years ago. Two possible present-day dormant descendants of this population of active black holes have been found in the galaxies NGC 3842 and NGC 4889 at the centres of the Leo and Coma galaxy clusters, which together form the central region of the Great Wall - the largest local structure of galaxies. The most luminous quasars, however, are not confined to such high-density regions of the early Universe; yet dormant black holes of this high mass have not yet been found outside of modern-day rich clusters. Here we report observations of the stellar velocity distribution in the galaxy NGC 1600 - a relatively isolated elliptical galaxy near the centre of a galaxy group at a distance of 64 Mpc from Earth. We use orbit superposition models to determine that the ...

  8. Masses of Nearby Supermassive Black Holes with Very-Long Baseline Interferometry

    CERN Document Server

    Johannsen, Tim; Gillessen, Stefan; Marrone, Daniel P; Ozel, Feryal; Doeleman, Sheperd S; Fish, Vincent L

    2012-01-01

    Dynamical mass measurements to date have allowed determinations of the mass M and the distance D of the galactic center black hole Sgr A* as well as those of other nearby supermassive black holes. In the case of Sgr A*, these measurements are limited by a degeneracy between the mass and distance scaling roughly as M ~ D^2. Future very-long baseline interferometric observations will image a bright and narrow ring surrounding the shadow of the supermassive black hole, if its accretion flow is optically thin. In this paper, we show that the combination of dynamical measurements and VLBI imaging of the ring of Sgr A* breaks the degeneracy between mass and distance. We estimate the signal to noise ratio of near-future VLBI arrays consisting of five to six stations and simulate measurements of the mass and distance of Sgr A* using the expected size of the ring image and existing data of stellar ephemerides. We demonstrate that VLBI observations at 1 mm can already improve the error on the mass by a factor of three ...

  9. The Black Hole Mass - Pitch Angle Relation of Type I AGN In Spiral Galaxies

    Science.gov (United States)

    Schilling, Amanda; Jones, Logan; Hughes, John A.; Barrows, R. Scott; Kennefick, Julia D.

    2017-01-01

    A relationship between the mass of supermassive black holes, M, at the center of galaxies and the pitch angle, P, a measure of tightness of spiral arms, was recently reported by Berrier, et al. (2013 ApJ 769, 132) for late type galaxies. The relationship, established for a local sample, shows that spiral galaxies with tighter pitch angles host higher mass black holes. In this work, we explore the M-P relation for a sample of 50 low to moderate redshift (0.04mass scaling relations to estimate black-hole mass. Pitch angles were measured using a 2DFFT technique (Davis, et al., 2012 ApJS 199, 33). We find that the M-P relation for the higher redshift, AGN sample differs from that of the local sample and discuss the possibility of AGN feedback by looking at a proposed Fundamental Plane for late-type galaxies - a correlation between bulge mass, disk mass, and spiral-arm pitch angle (Davis, et al. 2015, ApJ 802, L13).

  10. Black hole accretion discs

    CERN Document Server

    Lasota, Jean-Pierre

    2015-01-01

    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.

  11. Life inside black holes

    CERN Document Server

    Dokuchaev, V I

    2012-01-01

    We consider test planet and photon orbits of the third kind inside a black hole, which are stable, periodic and neither come out of the black hole nor terminate at the singularity. Interiors of supermassive black holes may be inhabited by advanced civilizations living on planets with the third-kind orbits. In principle, one can get information from the interiors of black holes by observing their white hole counterparts.

  12. A mass estimate of an intermediate-mass black hole in ω Centauri

    Science.gov (United States)

    Miocchi, P.

    2010-05-01

    Context. The problem of the existence of intermediate-mass black holes (IMBHs) at the centre of globular clusters is a hot and controversial topic in current astrophysical research with important implications in stellar and galaxy formation. Aims: The purpose of this paper is to provide further evidence on the presence of an IMBH in ω Centauri and to give an independent estimate of its mass. Methods: We employed a self-consistent spherical model with anisotropic velocity distribution. It consists in a generalisation of the King model by including the Bahcall-Wolf distribution function in the IMBH vicinity. Results: By the parametric fitting of the model to recent HST/ACS data for the surface brightness profile, we found an IMBH to cluster total mass ratio of M_bullet /M = 5.8-1.2+0.9 × 10-3. It is also found that the model yields a fit of the line-of-sight velocity dispersion profile that is better without mass segregation than in the segregated case. This confirms the current thought of a non-relaxed status for this peculiar cluster. The best fit model to the kinematic data leads, moreover, to a cluster total mass estimate of M = (3.1 ± 0.3) × 106 M_⊙, thus giving an IMBH mass in the range 1.3×104 confidence level). A slight degree of radial velocity anisotropy in the outer region (r ⪆ 12') is required to match the outer surface brightness profile.

  13. A 15.65-solar-mass black hole in an eclipsing binary in the nearby spiral galaxy M 33.

    Science.gov (United States)

    Orosz, Jerome A; McClintock, Jeffrey E; Narayan, Ramesh; Bailyn, Charles D; Hartman, Joel D; Macri, Lucas; Liu, Jiefeng; Pietsch, Wolfgang; Remillard, Ronald A; Shporer, Avi; Mazeh, Tsevi

    2007-10-18

    Stellar-mass black holes are found in X-ray-emitting binary systems, where their mass can be determined from the dynamics of their companion stars. Models of stellar evolution have difficulty producing black holes in close binaries with masses more than ten times that of the Sun (>10; ref. 4), which is consistent with the fact that the most massive stellar black holes known so far all have masses within one standard deviation of 10. Here we report a mass of (15.65 +/- 1.45) for the black hole in the recently discovered system M 33 X-7, which is located in the nearby galaxy Messier 33 (M 33) and is the only known black hole that is in an eclipsing binary. To produce such a massive black hole, the progenitor star must have retained much of its outer envelope until after helium fusion in the core was completed. On the other hand, in order for the black hole to be in its present 3.45-day orbit about its (70.0 +/- 6.9) companion, there must have been a 'common envelope' phase of evolution in which a significant amount of mass was lost from the system. We find that the common envelope phase could not have occurred in M 33 X-7 unless the amount of mass lost from the progenitor during its evolution was an order of magnitude less than what is usually assumed in evolutionary models of massive stars.

  14. Uncertainties of the masses of black holes and Eddington ratios in AGN

    CERN Document Server

    Collin, S

    2006-01-01

    Black hole masses in Active Galactic Nuclei have been determined in 35 objects through reverberation mapping of the emission line region. I mention some uncertainties of the method, such as the ``scale factor'' relating the Virial Product to the mass, which depends on the unknown structure and dynamics of the Broad Line Region. When the black hole masses are estimated indirectly using the empirical size-luminosity relation deduced from this method, the uncertainties can be larger, especially when the relation is extrapolated to high and low masses and/or luminosities. In particular they lead to Eddington ratios of the order of unity in samples of Narrow Line Seyfert 1. As the optical-UV luminosity is provided by the accretion disk, the accretion rates can be determined and are found to be much larger than the Eddington rates. So, accretion must be performed at a super-critical rate through a slim disk, resulting in rapid growth of the black holes. The alternative is that the mass determination is wrong at thi...

  15. Investigating the AGN activity and black hole masses in low surface brightness galaxies

    Science.gov (United States)

    Subramanian, Smitha; Sethuram, Ramya; Das, Mousumi; George, Koshy; Thirupathi, Sivarani; Prabhu, Tushar P.

    2016-02-01

    We present an analysis of the optical nuclear spectra from the active galactic nuclei (AGN) in a sample of giant low surface brightness (GLSB) galaxies. GLSB galaxies are extreme late type spirals that are large, isolated and poorly evolved compared to regular spiral galaxies. Earlier studies have indicated that their nuclei have relatively low mass black holes. Using data from the Sloan Digital Sky Survey (SDSS), we selected a sample of 30 GLSB galaxies that showed broad Hα emission lines in their AGN spectra. In some galaxies such as UGC 6284, the broad component of Hα is more related to outflows rather than the black hole. One galaxy (UGC 6614) showed two broad components in Hα, one associated with the black hole and the other associated with an outflow event. We derived the nuclear black hole (BH) masses of 29 galaxies from their broad Hα parameters. We find that the nuclear BH masses lie in the range 105 - 107 M⊙. The bulge stellar velocity dispersion σ e was determined from the underlying stellar spectra. We compared our results with the existing BH mass - velocity dispersion (M BH-σ e ) correlations and found that the majority of our sample lie in the low BH mass regime and below the M BH-σ e correlation. The effects of galaxy orientation in the measurement of σ e and the increase of σ e due to the effects of bar are probable reasons for the observed offset for some galaxies, but in many galaxies the offset is real. A possible explanation for the M BH-σ e offset could be lack of mergers and accretion events in the history of these galaxies which leads to a lack of BH-bulge co-evolution.

  16. The Black Hole - Bulge Mass Relation in Megamaser Host Galaxies

    CERN Document Server

    Läsker, Ronald; Seth, Anil; van de Ven, Glenn; Braatz, James A; Henkel, Christian; Lo, K Y

    2016-01-01

    We present HST images for nine megamaser disk galaxies with the primary goal of studying photometric BH-galaxy scaling relations. The megamaser disks provide the highest-precision extragalactic BH mass measurements, while our high-resolution HST imaging affords us the opportunity to decompose the complex nuclei of their late-type hosts in detail. Based on the morphologies and shapes of the galaxy nuclei, we argue that most of these galaxies' central regions contain secularly evolving components (pseudo-bulges), and in many cases we photometrically identify co-existing "classical" bulge components as well. Using these decompositions, we draw the following conclusions: (1) The megamaser BH masses span two orders of magnitude ($10^6$ -- $10^8 M_\\odot$) while the stellar mass of their spiral host galaxies are all $\\sim 10^{11} M_\\odot$ within a factor of three; (2) the BH masses at a given bulge mass or total stellar mass in the megamaser host spiral galaxies tend to be lower than expected, when compared to an ex...

  17. Universal charge-mass relation: From black holes to atomic nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Hod, Shahar, E-mail: shaharhod@gmail.co [The Ruppin Academic Center, Emeq Hefer 40250 (Israel); The Hadassah Institute, Jerusalem 91010 (Israel)

    2010-10-04

    The cosmic censorship hypothesis, introduced by Penrose forty years ago, is one of the corner stones of general relativity. This conjecture asserts that spacetime singularities that arise in gravitational collapse are always hidden inside of black holes. The elimination of a black-hole horizon is ruled out by this principle because that would expose naked singularities to distant observers. We test the consistency of this prediction in a gedanken experiment in which a charged object is swallowed by a charged black hole. We find that the validity of the cosmic censorship conjecture requires the existence of a charge-mass bound of the form q{<=}{mu}{sup 2/3}E{sub c}{sup -1/3}, where q and {mu} are the charge and mass of the physical system respectively, and E{sub c} is the critical electric field for pair-production. Applying this bound to charged atomic nuclei, one finds an upper limit on the number Z of protons in a nucleus of given mass number A: Z{<=}Z{sup *}={alpha}{sup -1/3}A{sup 2/3}, where {alpha}=e{sup 2}/h is the fine structure constant. We test the validity of this novel bound against the (Z,A)-relation of atomic nuclei as deduced from the Weizsaecker semi-empirical mass formula.

  18. A Low-mass Black Hole in the Nearby Seyfert Galaxy UGC 06728

    Science.gov (United States)

    Bentz, Misty C.; Batiste, Merida; Seals, James; Garcia, Karen; Kuzio de Naray, Rachel; Peters, Wesley; Anderson, Matthew D.; Jones, Jeremy; Lester, Kathryn; Machuca, Camilo; Parks, J. Robert; Pope, Crystal L.; Revalski, Mitchell; Roberts, Caroline A.; Saylor, Dicy; Sevrinsky, R. Andrew; Turner, Clay

    2016-11-01

    We present the results of a recent reverberation mapping campaign for UGC 06728, a nearby low-luminosity Seyfert 1 in a late-type galaxy. Nightly monitoring in the spring of 2015 allowed us to determine an Hβ time delay of τ =1.4+/- 0.8 days. Combined with the width of the variable Hβ line profile, we determine a black hole mass of {M}{BH}=(7.1+/- 4.0)× {10}5 {M}⊙ . We also constrain the bulge stellar velocity dispersion from higher-resolution long-slit spectroscopy along the galaxy minor axis and find {σ }\\star =51.6+/- 4.9 km s-1. The measurements presented here are in good agreement with both the {R}{BLR}{--}L relationship and the {M}{BH}{--}{σ }\\star relationship for active galactic nuclei. Combined with a previously published spin measurement, our mass determination for UGC 06728 makes it the lowest-mass black hole that has been fully characterized, and thus an important object to help anchor the low-mass end of black hole evolutionary models.

  19. Accretion Disks Around Binary Black Holes of Unequal Mass: GRMHD Simulations Near Decoupling

    Science.gov (United States)

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

    2013-01-01

    We report on simulations in general relativity of magnetized disks onto black hole binaries. We vary the binary mass ratio from 1:1 to 1:10 and evolve the systems when they orbit near the binary disk decoupling radius. We compare (surface) density profiles, accretion rates (relative to a single, non-spinning black hole), variability, effective alpha-stress levels and luminosities as functions of the mass ratio. We treat the disks in two limiting regimes: rapid radiative cooling and no radiative cooling. The magnetic field lines clearly reveal jets emerging from both black hole horizons and merging into one common jet at large distances. The magnetic fields give rise to much stronger shock heating than the pure hydrodynamic flows, completely alter the disk structure, and boost accretion rates and luminosities. Accretion streams near the horizons are among the densest structures; in fact, the 1:10 no-cooling evolution results in a refilling of the cavity. The typical effective temperature in the bulk of the disk is approx. 10(exp5) (M / 10(exp 8)M solar mass (exp -1/4(L/L(sub edd) (exp 1/4K) yielding characteristic thermal frequencies approx. 10 (exp 15) (M /10(exp 8)M solar mass) (exp -1/4(L/L (sub edd) (1+z) (exp -1)Hz. These systems are thus promising targets for many extragalactic optical surveys, such as LSST, WFIRST, and PanSTARRS.

  20. Further Evidence for a Supermassive Black Hole Mass - Pitch Angle Relation

    CERN Document Server

    Berrier, Joel C; Kennefick, Daniel; Kennefick, Julia D; Seigar, Marc S; Barrows, R Scott; Hartley, Matthew; Shields, Doug; Bentz, Misty C; Lacy, Claud H S

    2013-01-01

    We present new and stronger evidence for a previously reported relationship between galactic spiral arm pitch angle P (a measure of the tightness of spiral structure) and the mass M_BH of a disk galaxy's nuclear supermassive black hole (SMBH). We use an improved method to accurately measure the spiral arm pitch angle in disk galaxies to generate quantitative data on this morphological feature for 34 galaxies with directly measured black hole masses. We find a relation of log(M/M_sun) = (8.21 +/- 0.16) - (0.062 +/- 0.009)P. This method is compared with other means of estimating black hole mass to determine its effectiveness and usefulness relative to other existing relations. We argue that such a relationship is predicted by leading theories of spiral structure in disk galaxies, including the density wave theory. We propose this relationship as a tool for estimating SMBH masses in disk galaxies. This tool is potentially superior when compared to other methods for this class of galaxy, and has the advantage of ...

  1. Further evidence for a supermassive black hole mass-pitch angle relation

    Energy Technology Data Exchange (ETDEWEB)

    Berrier, Joel C.; Kennefick, Daniel; Kennefick, Julia D.; Hartley, Matthew; Lacy, Claud H. S. [Department of Physics, University of Arkansas, 825 West Dickson Street, Fayetteville, AR 72701 (United States); Davis, Benjamin L.; Barrows, Robert Scott; Shields, Doug [Arkansas Center for Space and Planetary Sciences, University of Arkansas, 202 Old Field House, Fayetteville, AR 72701 (United States); Seigar, Marc S. [Department of Physics and Astronomy, University of Arkansas at Little Rock, 2801 South University Avenue, Little Rock, AR 72204 (United States); Bentz, Misty C. [Department of Physics and Astronomy, Georgia State University, Atlanta, GA 30303 (United States)

    2013-06-01

    We present new and stronger evidence for a previously reported relationship between galactic spiral arm pitch angle P (a measure of the tightness of spiral structure) and the mass M {sub BH} of a disk galaxy's nuclear supermassive black hole (SMBH). We use an improved method to accurately measure the spiral arm pitch angle in disk galaxies to generate quantitative data on this morphological feature for 34 galaxies with directly measured black hole masses. We find a relation of log (M/M {sub ☉}) = (8.21 ± 0.16) – (0.062 ± 0.009)P. This method is compared with other means of estimating black hole mass to determine its effectiveness and usefulness relative to other existing relations. We argue that such a relationship is predicted by leading theories of spiral structure in disk galaxies, including the density wave theory. We propose this relationship as a tool for estimating SMBH masses in disk galaxies. This tool is potentially superior when compared to other methods for this class of galaxy and has the advantage of being unambiguously measurable from imaging data alone.

  2. AGN Activity and Black Hole Masses in Low Surface Brightness Galaxies

    CERN Document Server

    Ramya, S; Das, M

    2011-01-01

    We present medium resolution optical spectroscopy of a sample of nine Low Surface Brightness (LSB) galaxies. For those that show clear signatures of AGN emission, we have disentangled the AGN component from stellar light and any Fe I and Fe II contribution. We have decomposed the H_alpha line into narrow and broad components and determined the velocities of the broad components; typical values lie between 900--2500 km/s. Of the galaxies in our study, UGC 6614, UGC 1922, UGC 6968 and LSBC F568-6 (Malin~2) show clear signatures of AGN activity. We have calculated the approximate black hole masses for these galaxies from the H_alpha line emission using the virial approximation. The black hole masses are ~3x10^{5} M_sun for three galaxies and lie in the intermediate mass black holes domain rather than the supermassive range. UGC 6614 harbors a BH of mass 3.8x10^{6} M_sun; it also shows an interesting feature blueward of H_alpha and H_beta implying outflow of gas or a one-sided jet streaming towards us. We have al...

  3. A Low-Mass Black Hole in the Nearby Seyfert Galaxy UGC 06728

    CERN Document Server

    Bentz, Misty C; Seals, James; Garcia, Karen; de Naray, Rachel Kuzio; Peters, Wesley; Anderson, Matthew D; Jones, Jeremy; Lester, Kathryn; Machuca, Camilo; Parks, J Robert; Pope, Crystal L; Revalski, Mitchell; Roberts, Caroline A; Saylor, Dicy; Sevrinsky, R Andrew; Turner, Clay

    2016-01-01

    We present the results of a recent reverberation mapping campaign for UGC 06728, a nearby low-luminosity Seyfert 1 in a late-type galaxy. Nightly monitoring in the spring of 2015 allowed us to determine an H$\\beta$ time delay of $\\tau = 1.4 \\pm 0.8$ days. Combined with the width of the variable H$\\beta$ line profile, we determine a black hole mass of $M_{\\rm BH} = (7.1 \\pm 4.0) \\times 10^5$ M$_{\\odot}$. We also constrain the bulge stellar velocity dispersion from higher-resolution long slit spectroscopy along the galaxy minor axis and find $\\sigma_{\\star} = 51.6 \\pm 4.9$ km s$^{-1}$. The measurements presented here are in good agreement with both the $R_{\\rm BLR} - L$ relationship and the $M_{\\rm BH}-\\sigma_{\\star}$ relationship for AGNs. Combined with a previously published spin measurement, our mass determination for UGC 06728 makes it the lowest-mass black hole that has been fully characterized, and thus an important object to help anchor the low-mass end of black hole evolutionary models.

  4. Black hole hair removal

    Science.gov (United States)

    Banerjee, Nabamita; Mandal, Ipsita; Sen, Ashoke

    2009-07-01

    Macroscopic entropy of an extremal black hole is expected to be determined completely by its near horizon geometry. Thus two black holes with identical near horizon geometries should have identical macroscopic entropy, and the expected equality between macroscopic and microscopic entropies will then imply that they have identical degeneracies of microstates. An apparent counterexample is provided by the 4D-5D lift relating BMPV black hole to a four dimensional black hole. The two black holes have identical near horizon geometries but different microscopic spectrum. We suggest that this discrepancy can be accounted for by black hole hair — degrees of freedom living outside the horizon and contributing to the degeneracies. We identify these degrees of freedom for both the four and the five dimensional black holes and show that after their contributions are removed from the microscopic degeneracies of the respective systems, the result for the four and five dimensional black holes match exactly.

  5. Black Hole Hair Removal

    CERN Document Server

    Banerjee, Nabamita; Sen, Ashoke

    2009-01-01

    Macroscopic entropy of an extremal black hole is expected to be determined completely by its near horizon geometry. Thus two black holes with identical near horizon geometries should have identical macroscopic entropy, and the expected equality between macroscopic and microscopic entropies will then imply that they have identical degeneracies of microstates. An apparent counterexample is provided by the 4D-5D lift relating BMPV black hole to a four dimensional black hole. The two black holes have identical near horizon geometries but different microscopic spectrum. We suggest that this discrepancy can be accounted for by black hole hair, -- degrees of freedom living outside the horizon and contributing to the degeneracies. We identify these degrees of freedom for both the four and the five dimensional black holes and show that after their contributions are removed from the microscopic degeneracies of the respective systems, the result for the four and five dimensional black holes match exactly.

  6. Detecting intermediate mass black holes in globular clusters with machine learning

    CERN Document Server

    Pasquato, Mario

    2016-01-01

    Mergers of stellar-mass black holes were recently observed in the gravitational wave window opened by LIGO. This puts the spotlight on dense stellar systems and their ability to create intermediate-mass black holes (IMBHs) through repeated merging. Unfortunately, attempts at direct and indirect IMBH detection in star clusters in the nearby universe have proven inconclusive as of now. Indirect detection methods attempt to constrain IMBHs through their effect on star cluster photometric and kinematic observables. They are usually based on looking for a specific, physically motivated signature. While this approach is justified, it may be suboptimal in its usage of the available data. Here I present a new indirect detection method, based on machine learning, that is unaffected by these restrictions. I reduce the scientific question whether a star cluster hosts an IMBH to a classification problem in the machine learning framework. I present preliminary results to illustrate how machine learning models are trained ...

  7. Mapping the Broad-band Spectrum of a New Candidate Intermediate Mass Black Hole

    Science.gov (United States)

    Farrell, Sean

    2014-10-01

    We request joint XMM-Newton & HST observations of a new intermediate mass black hole candidate in the galaxy LEDA 87326 to map the broad-band spectral energy distribution from X-ray to near-IR. Previous observations with the XMM-Newton EPIC and OM cameras detected an X-ray source with an observed 0.2-10 keV luminosity of 6E41 erg/s, with the X-ray spectrum dominated by a hard power law and the UV/optical data consistent with thermal emission from a cool (~0.08 keV) accretion disc. The high X-ray luminosity and low disc temperature imply a black hole mass > 4000 Msun. By observing this source simultaneously with XMM-Newton and the HST we will confirm that the observed optical emission is from an accretion disc and determine whether any reprocessing in the outer disc is present.

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

    DEFF Research Database (Denmark)

    Denney, Kelly D.; Bentz, Misty C.; Peterson, Bradley M.

    2006-01-01

    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. Head-on collisions of unequal mass black holes in D=5 dimensions

    CERN Document Server

    Witek, Helvi; Gualtieri, Leonardo; Herdeiro, Carlos; Sperhake, Ulrich; Zilhao, Miguel

    2010-01-01

    We study head-on collisions of unequal mass black hole binaries in D=5 space-time dimensions, with mass ratios between 1:1 and 1:4. Information about gravitational radiation is extracted by using the Kodama-Ishibashi gauge-invariant formalism and details of the apparent horizon of the final black hole. For the first time, we present waveforms, total integrated energy and momentum for this process. Our results show surprisingly good agreement, within 5% or less, with those extrapolated from linearized, point-particle calculations. Our results also show that consistency with the area theorem bound requires that the same process in a large number of spacetime dimensions must display new features.

  10. The central black hole masses for the γ-ray loud blazars

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The Large Area Telescope (LAT) on the Fermi Gamma-ray Space Telescope (formerly GLAST) provides an increase in sensitivity and has detected rapid variability of gamma-ray sources.The variability time scales detected from the gamma-ray loud blazars by LAT and EGRET,and gamma-ray luminosity are used to estimate the central black hole masses.In this work,we find that the lower limits of central black hole masses are in a range of (0.3-24)×107M⊙,which are compared with those obtained by other authors.Our results are consistent with other authors’ results.Also,the Lorentz factor,Γ,and the propagation angle,θ,are obtained for 18 blazars for which superluminal motions are known.

  11. Estimation of mass outflow rates from viscous relativistic accretion discs around black holes

    CERN Document Server

    Chattopadhyay, Indranil

    2016-01-01

    We investigated flow in Schwarzschild metric, around a non-rotating black hole and obtained self-consistent accretion - ejection solution in full general relativity. We covered the whole of parameter space in the advective regime to obtain shocked, as well as, shock-free accretion solution. We computed the jet streamline using von - Zeipel surfaces and projected the jet equations of motion on to the streamline and solved them simultaneously with the accretion disc equations of motion. We found that steady shock cannot exist {for $\\alpha \\gsim0.06$} in the general relativistic prescription, but is lower if mass - loss is considered too. We showed that for fixed outer boundary, the shock moves closer to the horizon with increasing viscosity parameter. The mass outflow rate increases as the shock moves closer to the black hole, but eventually decreases, maximizing at some intermediate value of shock {location}. The jet terminal speed increases with stronger shocks, quantitatively speaking, the terminal speed of ...

  12. Megamaser Disks Reveal a Broad Distribution of Black Hole Mass in Spiral Galaxies

    CERN Document Server

    Greene, Jenny E; Kim, Minjin; Laesker, Ronald; Goulding, Andy D; Gao, Feng; Braatz, James A; Henkel, Christian; Condon, James; Lo, Fred K Y; Zhao, Wei

    2016-01-01

    We use new precision measurements of black hole masses from water megamaser disks to investigate scaling relations between macroscopic galaxy properties and supermassive black hole (BH) mass. The megamaser-derived BH masses span 10^6-10^8 M_sun, while all the galaxy properties that we examine (including stellar mass, central mass density, central velocity dispersion) lie within a narrow range. Thus, no galaxy property correlates tightly with M_BH in ~L* spiral galaxies. Of them all, stellar velocity dispersion provides the tightest relation, but at fixed sigma* the mean megamaser M_BH are offset by -0.6+/-0.1 dex relative to early-type galaxies. Spiral galaxies with non-maser dynamical BH masses do not show this offset. At low mass, we do not yet know the full distribution of BH mass at fixed galaxy property; the non-maser dynamical measurements may miss the low-mass end of the BH distribution due to inability to resolve the spheres of influence and/or megamasers may preferentially occur in lower-mass BHs.

  13. Black holes and the multiverse

    CERN Document Server

    Garriga, Jaume; Zhang, Jun

    2015-01-01

    Vacuum bubbles may nucleate and expand during the inflationary epoch in the early universe. After inflation ends, the bubbles quickly dissipate their kinetic energy; they come to rest with respect to the Hubble flow and eventually form black holes. The fate of the bubble itself depends on the resulting black hole mass. If the mass is smaller than a certain critical value, the bubble collapses to a singularity. Otherwise, the bubble interior inflates, forming a baby universe, which is connected to the exterior FRW region by a wormhole. A similar black hole formation mechanism operates for spherical domain walls nucleating during inflation. As an illustrative example, we studied the black hole mass spectrum in the domain wall scenario, assuming that domain walls interact with matter only gravitationally. Our results indicate that, depending on the model parameters, black holes produced in this scenario can have significant astrophysical effects and can even serve as dark matter or as seeds for supermassive blac...

  14. Noncommutative black holes

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-DomInguez, J C [Instituto de Fisica de la Universidad de Guanajuato PO Box E-143, 37150 Leoen Gto. (Mexico); Obregon, O [Instituto de Fisica de la Universidad de Guanajuato PO Box E-143, 37150 Leoen Gto. (Mexico); RamIrez, C [Facultad de Ciencias FIsico Matematicas, Universidad Autonoma de Puebla, PO Box 1364, 72000 Puebla (Mexico); Sabido, M [Instituto de Fisica de la Universidad de Guanajuato PO Box E-143, 37150 Leoen Gto. (Mexico)

    2007-11-15

    We study noncommutative black holes, by using 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 Hawking's temperature and entropy for the 'noncommutative' Schwarzschild black hole.

  15. Black Hole Thermodynamics

    Science.gov (United States)

    Israel, Werner

    This chapter reviews the conceptual developments on black hole thermodynamics and the attempts to determine the origin of black hole entropy in terms of their horizon area. The brick wall model and an operational approach are discussed. An attempt to understand at the microlevel how the quantum black hole acquires its thermal properties is included. The chapter concludes with some remarks on the extension of these techniques to describing the dynamical process of black hole evaporation.

  16. Adaptive Optics Assisted 3D spectroscopy observations for black hole mass measurements

    OpenAIRE

    Pastorini, Guia

    2006-01-01

    The very high spatial resolution provided by Adaptive Optics assisted spectroscopic observations at 8m-class telescopes (e.g. with SINFONI at the VLT) will allow to greatly increase the number of direct black hole (BH) mass measurements which is currently very small. This is a fundamental step to investigate the tight link between galaxy evolution and BH growth, revealed by the existing scaling relations between $M_{BH}$ and galaxy structural parameters. I present preliminary results from SIN...

  17. Re-scrutiny of a best intermediate mass black hole candidate M82 X-1

    Science.gov (United States)

    Liu, Jifeng; Xu, Xiaojie; Qiu, Yanli; Wang, Song

    2015-08-01

    While several recent works on ultraluminous X-ray sources show some of them to be stellar mass black holes or even neutron stars with special radiation mechanisms, M82 X-1 remains one of the best intermediate mass black hole candidates in the local universe. It exhibits amazing properties including quasi-periodic oscillations and extremely high X-ray luminosities suggesting an intermediate mass black hole, a 62-day orbital period from RXTE observations suggestive of a supergiant secondary, and possible radio flare emission that could result from relativistic beaming. Recently we have re-scrutinized this source with a wealth of data from Chandra, Swift/XRT and Hubble, and found three surprises about M82 X-1. Firstly, there is an X-ray transient that is only 1" away from M82 X-1, which has a peak luminosity only 1% of M82 X-1 and is usually hidden in the shadow of M82 X-1. This X-ray transient is associated with the previously reported radio flare. Secondly, two years' Swift/XRT observations, with much much better spatial resolution than RXTE observations, have shown that the 62-day period comes from another nearby less brighter ultra-luminous X-ray source, but definitely not from M82 X-1. Thirdly, we find an optical counterpart for M82 X-1 within the newly obtained 0.4" error circle on Hubble images, and its spectral energy distribution from Hubble photometry shows that it has excessive Halpha emission but no excessive SII emission. This lack of excessive SII emission suggests that the Halpha emission is not from the surrounding nebula but from an accretion disk. The monitoring of this Halpha emission line will allow us to determine the mass of the black hole via dynamical means.

  18. Core-dominance parameter, black hole mass and jet-disc connection in Fermi blazars

    OpenAIRE

    Chen, Y. Y.; Zhang, X.; Zhang, H. J.; X. L. Yu

    2015-01-01

    We study the relationship between jet power and accretion for Fermi and non-Fermi blazars, respectively. We also compare the relevant parameter between them. Our main results are as follows. (i) Fermi and non-Fermi blazars have significant difference in redshift, black hole mass, and broad line luminosity. (ii) Fermi blazars have higher average core-dominance parameter than non-Fermi blazars, which suggests that Fermi blazars have strong beaming effect. (iii) We find significant correlation b...

  19. Power-law mass inflation in Einstein-Yang-Mills-Higgs black holes

    CERN Document Server

    Galtsov, D V

    1997-01-01

    Analytical formulas are presented describing a generic singularity inside the static spherically symmetric black holes in the SU(2) Einstein-Yang-Mills-Higgs theories with triplet or doublet Higgs field. The singularity is spacelike and exhibits a `power-low mass inflation'. Alternatively this asymptotic may be interpreted as a pointlike singularity with a non-vanishing shear in the Kantowski-Sachs anisotropic cosmology.

  20. Monopole black hole skyrmions

    OpenAIRE

    Moss, I. G.; Shiiki, N.; Winstanley, E.

    2000-01-01

    Charged black hole solutions with pion hair are discussed. These can be\\ud used to study monopole black hole catalysis of proton decay.\\ud There also exist\\ud multi-black hole skyrmion solutions with BPS monopole behaviour.

  1. THE BLACK HOLE MASS-GALAXY LUMINOSITY RELATIONSHIP FOR SLOAN DIGITAL SKY SURVEY QUASARS

    Energy Technology Data Exchange (ETDEWEB)

    Salviander, S.; Shields, G. A. [Department of Astronomy, University of Texas, Austin, TX 78712 (United States); Bonning, E. W., E-mail: triples@astro.as.utexas.edu, E-mail: shields@astro.as.utexas.edu, E-mail: erin.bonning@emory.edu [Department of Physics, Emory University, Atlanta, GA 30322 (United States)

    2015-02-01

    We investigate the relationship between the mass of the central supermassive black hole, M {sub BH}, and the host galaxy luminosity, L {sub gal}, in a sample of quasars from the Sloan Digital Sky Survey Data Release 7. We use composite quasar spectra binned by black hole mass and redshift to assess galaxy features that would otherwise be overwhelmed by noise in individual spectra. The black hole mass is calculated using the photoionization method, and the host galaxy luminosity is inferred from the depth of the Ca II H+K features in the composite spectra. We evaluate the evolution in the M {sub BH}-L {sub gal} relationship by examining the redshift dependence of Δ log M {sub BH}, the offset in M {sub BH} from the local M {sub BH}-L {sub gal} relationship. There is little systematic trend in Δ log M {sub BH} out to z = 0.8. Using the width of the [O III] emission line as a proxy for the stellar velocity dispersion, σ{sub *}, we find agreement of our derived host luminosities with the locally observed Faber-Jackson relation. This supports the utility of the width of the [O III] line as a proxy for σ{sub *} in statistical studies.

  2. The Source of Mass Accreted by the Central Black Hole in Cooling Flow Clusters

    CERN Document Server

    Soker, N

    2006-01-01

    This paper reports the study of the cold-feedback heating in cooling flow clusters. In the cold-feedback model the mass accreted by the central black hole originates in non-linear over-dense blobs of gas residing in an extended region (r ~ 5-30 kpc); these blobs are originally hot, but then cool faster than their environment and sink toward the center. The intra-cluster medium (ICM) entropy profile must be shallow for the blobs to reach the center as cold blobs. I build a toy model to explore the role of the entropy profile and the population of dense blobs in the cold-feedback mechanism. The mass accretion rate by the central black hole is determined by the cooling time of the ICM, the entropy profile, and the presence of inhomogeneities. The mass accretion rate determines the energy injected by the black hole back to the ICM. These active galactic nucleus (AGN) outbursts not only heat the ICM, but also change the entropy profile in the cluster and cause inhomogeneities that are the seeds of future dense blo...

  3. GW151226: Observation of Gravitational Waves from a 22-Solar-Mass Binary Black Hole Coalescence.

    Science.gov (United States)

    Abbott, B P; Abbott, R; Abbott, T D; Abernathy, M R; Acernese, F; Ackley, K; Adams, C; Adams, T; Addesso, P; Adhikari, R X; Adya, V B; Affeldt, C; Agathos, M; Agatsuma, K; Aggarwal, N; Aguiar, O D; Aiello, L; Ain, A; Ajith, P; Allen, B; Allocca, A; Altin, P A; Anderson, S B; Anderson, W G; Arai, K; Araya, M C; Arceneaux, C C; Areeda, J S; Arnaud, N; Arun, K G; Ascenzi, S; Ashton, G; Ast, M; Aston, S M; Astone, P; Aufmuth, P; Aulbert, C; Babak, S; Bacon, P; Bader, M K M; Baker, P T; Baldaccini, F; Ballardin, G; Ballmer, S W; Barayoga, J C; Barclay, S E; Barish, B C; Barker, D; Barone, F; Barr, B; Barsotti, L; Barsuglia, M; Barta, D; Bartlett, J; Bartos, I; Bassiri, R; Basti, A; Batch, J C; Baune, C; Bavigadda, V; Bazzan, M; Bejger, M; Bell, A S; Berger, B K; Bergmann, G; Berry, C P L; Bersanetti, D; Bertolini, A; Betzwieser, J; Bhagwat, S; Bhandare, R; Bilenko, I A; Billingsley, G; Birch, J; Birney, R; Birnholtz, O; Biscans, S; Bisht, A; Bitossi, M; Biwer, C; Bizouard, M A; Blackburn, J K; Blair, C D; Blair, D G; Blair, R M; Bloemen, S; Bock, O; Boer, M; Bogaert, G; Bogan, C; Bohe, A; Bond, C; Bondu, F; Bonnand, R; Boom, B A; Bork, R; Boschi, V; Bose, S; Bouffanais, Y; Bozzi, A; Bradaschia, C; Brady, P R; Braginsky, V B; Branchesi, M; Brau, J E; Briant, T; Brillet, A; Brinkmann, M; Brisson, V; Brockill, P; Broida, J E; Brooks, A F; Brown, D A; Brown, D D; Brown, N M; Brunett, S; Buchanan, C C; Buikema, A; Bulik, T; Bulten, H J; Buonanno, A; Buskulic, D; Buy, C; Byer, R L; Cabero, M; Cadonati, L; Cagnoli, G; Cahillane, C; Calderón Bustillo, J; Callister, T; Calloni, E; Camp, J B; Cannon, K C; Cao, J; Capano, C D; Capocasa, E; Carbognani, F; Caride, S; Casanueva Diaz, J; Casentini, C; Caudill, S; Cavaglià, M; Cavalier, F; Cavalieri, R; Cella, G; Cepeda, C B; Cerboni Baiardi, L; Cerretani, G; Cesarini, E; Chamberlin, S J; Chan, M; Chao, S; Charlton, P; Chassande-Mottin, E; Cheeseboro, B D; Chen, H Y; Chen, Y; Cheng, C; Chincarini, A; Chiummo, A; Cho, H S; Cho, M; Chow, J H; Christensen, N; Chu, Q; Chua, S; Chung, S; Ciani, G; Clara, F; Clark, J A; Cleva, F; Coccia, E; Cohadon, P-F; Colla, A; Collette, C G; Cominsky, L; Constancio, M; Conte, A; Conti, L; Cook, D; Corbitt, T R; Cornish, N; Corsi, A; Cortese, S; Costa, C A; Coughlin, M W; Coughlin, S B; Coulon, J-P; Countryman, S T; Couvares, P; Cowan, E E; Coward, D M; Cowart, M J; Coyne, D C; Coyne, R; Craig, K; Creighton, J D E; Cripe, J; Crowder, S G; Cumming, A; Cunningham, L; Cuoco, E; Dal Canton, T; Danilishin, S L; D'Antonio, S; Danzmann, K; Darman, N S; Dasgupta, A; Da Silva Costa, C F; Dattilo, V; Dave, I; Davier, M; Davies, G S; Daw, E J; Day, R; De, S; DeBra, D; Debreczeni, G; Degallaix, J; De Laurentis, M; Deléglise, S; Del Pozzo, W; Denker, T; Dent, T; Dergachev, V; De Rosa, R; DeRosa, R T; DeSalvo, R; Devine, R C; Dhurandhar, S; Díaz, M C; Di Fiore, L; Di Giovanni, M; Di Girolamo, T; Di Lieto, A; Di Pace, S; Di Palma, I; Di Virgilio, A; Dolique, V; Donovan, F; Dooley, K L; Doravari, S; Douglas, R; Downes, T P; Drago, M; Drever, R W P; Driggers, J C; Ducrot, M; Dwyer, S E; Edo, T B; Edwards, M C; Effler, A; Eggenstein, H-B; Ehrens, P; Eichholz, J; Eikenberry, S S; Engels, W; Essick, R C; Etzel, T; Evans, M; Evans, T M; Everett, R; Factourovich, M; Fafone, V; Fair, H; Fairhurst, S; Fan, X; Fang, Q; Farinon, S; Farr, B; Farr, W M; Favata, M; Fays, M; Fehrmann, H; Fejer, M M; Fenyvesi, E; Ferrante, I; Ferreira, E C; Ferrini, F; Fidecaro, F; Fiori, I; Fiorucci, D; Fisher, R P; Flaminio, R; Fletcher, M; Fong, H; Fournier, J-D; Frasca, S; Frasconi, F; Frei, Z; Freise, A; Frey, R; Frey, V; Fritschel, P; Frolov, V V; Fulda, P; Fyffe, M; Gabbard, H A G; Gair, J R; Gammaitoni, L; Gaonkar, S G; Garufi, F; Gaur, G; Gehrels, N; Gemme, G; Geng, P; Genin, E; Gennai, A; George, J; Gergely, L; Germain, V; Ghosh, Abhirup; Ghosh, Archisman; Ghosh, S; Giaime, J A; Giardina, K D; Giazotto, A; Gill, K; Glaefke, A; Goetz, E; Goetz, R; Gondan, L; González, G; Gonzalez Castro, J M; Gopakumar, A; Gordon, N A; Gorodetsky, M L; Gossan, S E; Gosselin, M; Gouaty, R; Grado, A; Graef, C; Graff, P B; Granata, M; Grant, A; Gras, S; Gray, C; Greco, G; Green, A C; Groot, P; Grote, H; Grunewald, S; Guidi, G M; Guo, X; Gupta, A; Gupta, M K; Gushwa, K E; Gustafson, E K; Gustafson, R; Hacker, J J; Hall, B R; Hall, E D; Hamilton, H; Hammond, G; Haney, M; Hanke, M M; Hanks, J; Hanna, C; Hannam, M D; Hanson, J; Hardwick, T; Harms, J; Harry, G M; Harry, I W; Hart, M J; Hartman, M T; Haster, C-J; Haughian, K; Healy, J; Heidmann, A; Heintze, M C; Heitmann, H; Hello, P; Hemming, G; Hendry, M; Heng, I S; Hennig, J; Henry, J; Heptonstall, A W; Heurs, M; Hild, S; Hoak, D; Hofman, D; Holt, K; Holz, D E; Hopkins, P; Hough, J; Houston, E A; Howell, E J; Hu, Y M; Huang, S; Huerta, E A; Huet, D; Hughey, B; Husa, S; Huttner, S H; Huynh-Dinh, T; Indik, N; Ingram, D R; Inta, R; Isa, H N; Isac, J-M; Isi, M; Isogai, T; Iyer, B R; Izumi, K; Jacqmin, T; Jang, H; Jani, K; Jaranowski, P; Jawahar, S; Jian, L; Jiménez-Forteza, F; Johnson, W W; Johnson-McDaniel, N K; Jones, D I; Jones, R; Jonker, R J G; Ju, L; K, Haris; Kalaghatgi, C V; Kalogera, V; Kandhasamy, S; Kang, G; Kanner, J B; Kapadia, S J; Karki, S; Karvinen, K S; Kasprzack, M; Katsavounidis, E; Katzman, W; Kaufer, S; Kaur, T; Kawabe, K; Kéfélian, F; Kehl, M S; Keitel, D; Kelley, D B; Kells, W; Kennedy, R; Key, J S; Khalili, F Y; Khan, I; Khan, S; Khan, Z; Khazanov, E A; Kijbunchoo, N; Kim, Chi-Woong; Kim, Chunglee; Kim, J; Kim, K; Kim, N; Kim, W; Kim, Y-M; Kimbrell, S J; King, E J; King, P J; Kissel, J S; Klein, B; Kleybolte, L; Klimenko, S; Koehlenbeck, S M; Koley, S; Kondrashov, V; Kontos, A; Korobko, M; Korth, W Z; Kowalska, I; Kozak, D B; Kringel, V; Krishnan, B; Królak, A; Krueger, C; Kuehn, G; Kumar, P; Kumar, R; Kuo, L; Kutynia, A; Lackey, B D; Landry, M; Lange, J; Lantz, B; Lasky, P D; Laxen, M; Lazzarini, A; Lazzaro, C; Leaci, P; Leavey, S; Lebigot, E O; Lee, C H; Lee, H K; Lee, H M; Lee, K; Lenon, A; Leonardi, M; Leong, J R; Leroy, N; Letendre, N; Levin, Y; Lewis, J B; Li, T G F; Libson, A; Littenberg, T B; Lockerbie, N A; Lombardi, A L; London, L T; Lord, J E; Lorenzini, M; Loriette, V; Lormand, M; Losurdo, G; Lough, J D; Lousto, C O; Lück, H; Lundgren, A P; Lynch, R; Ma, Y; Machenschalk, B; MacInnis, M; Macleod, D M; Magaña-Sandoval, F; Magaña Zertuche, L; Magee, R M; Majorana, E; Maksimovic, I; Malvezzi, V; Man, N; Mandel, I; Mandic, V; Mangano, V; Mansell, G L; Manske, M; Mantovani, M; Marchesoni, F; Marion, F; Márka, S; Márka, Z; Markosyan, A S; Maros, E; Martelli, F; Martellini, L; Martin, I W; Martynov, D V; Marx, J N; Mason, K; Masserot, A; Massinger, T J; Masso-Reid, M; Mastrogiovanni, S; Matichard, F; Matone, L; Mavalvala, N; Mazumder, N; McCarthy, R; McClelland, D E; McCormick, S; McGuire, S C; McIntyre, G; McIver, J; McManus, D J; McRae, T; McWilliams, S T; Meacher, D; Meadors, G D; Meidam, J; Melatos, A; Mendell, G; Mercer, R A; Merilh, E L; Merzougui, M; Meshkov, S; Messenger, C; Messick, C; Metzdorff, R; Meyers, P M; Mezzani, F; Miao, H; Michel, C; Middleton, H; Mikhailov, E E; Milano, L; Miller, A L; Miller, A; Miller, B B; Miller, J; Millhouse, M; Minenkov, Y; Ming, J; Mirshekari, S; Mishra, C; Mitra, S; Mitrofanov, V P; Mitselmakher, G; Mittleman, R; Moggi, A; Mohan, M; Mohapatra, S R P; Montani, M; Moore, B C; Moore, C J; Moraru, D; Moreno, G; Morriss, S R; Mossavi, K; Mours, B; Mow-Lowry, C M; Mueller, G; Muir, A W; Mukherjee, Arunava; Mukherjee, D; Mukherjee, S; Mukund, N; Mullavey, A; Munch, J; Murphy, D J; Murray, P G; Mytidis, A; Nardecchia, I; Naticchioni, L; Nayak, R K; Nedkova, K; Nelemans, G; Nelson, T J N; Neri, M; Neunzert, A; Newton, G; Nguyen, T T; Nielsen, A B; Nissanke, S; Nitz, A; Nocera, F; Nolting, D; Normandin, M E N; Nuttall, L K; Oberling, J; Ochsner, E; O'Dell, J; Oelker, E; Ogin, G H; Oh, J J; Oh, S H; Ohme, F; Oliver, M; Oppermann, P; Oram, Richard J; O'Reilly, B; O'Shaughnessy, R; Ottaway, D J; Overmier, H; Owen, B J; Pai, A; Pai, S A; Palamos, J R; Palashov, O; Palomba, C; Pal-Singh, A; Pan, H; Pankow, C; Pannarale, F; Pant, B C; Paoletti, F; Paoli, A; Papa, M A; Paris, H R; Parker, W; Pascucci, D; Pasqualetti, A; Passaquieti, R; Passuello, D; Patricelli, B; Patrick, Z; Pearlstone, B L; Pedraza, M; Pedurand, R; Pekowsky, L; Pele, A; Penn, S; Perreca, A; Perri, L M; Pfeiffer, H P; Phelps, M; Piccinni, O J; Pichot, M; Piergiovanni, F; Pierro, V; Pillant, G; Pinard, L; Pinto, I M; Pitkin, M; Poe, M; Poggiani, R; Popolizio, P; Post, A; Powell, J; Prasad, J; Predoi, V; Prestegard, T; Price, L R; Prijatelj, M; Principe, M; Privitera, S; Prix, R; Prodi, G A; Prokhorov, L; Puncken, O; Punturo, M; Puppo, P; Pürrer, M; Qi, H; Qin, J; Qiu, S; Quetschke, V; Quintero, E A; Quitzow-James, R; Raab, F J; Rabeling, D S; Radkins, H; Raffai, P; Raja, S; Rajan, C; Rakhmanov, M; Rapagnani, P; Raymond, V; Razzano, M; Re, V; Read, J; Reed, C M; Regimbau, T; Rei, L; Reid, S; Reitze, D H; Rew, H; Reyes, S D; Ricci, F; Riles, K; Rizzo, M; Robertson, N A; Robie, R; Robinet, F; Rocchi, A; Rolland, L; Rollins, J G; Roma, V J; Romano, J D; Romano, R; Romanov, G; Romie, J H; Rosińska, D; Rowan, S; Rüdiger, A; Ruggi, P; Ryan, K; Sachdev, S; Sadecki, T; Sadeghian, L; Sakellariadou, M; Salconi, L; Saleem, M; Salemi, F; Samajdar, A; Sammut, L; Sanchez, E J; Sandberg, V; Sandeen, B; Sanders, J R; Sassolas, B; Sathyaprakash, B S; Saulson, P R; Sauter, O E S; Savage, R L; Sawadsky, A; Schale, P; Schilling, R; Schmidt, J; Schmidt, P; Schnabel, R; Schofield, R M S; Schönbeck, A; Schreiber, E; Schuette, D; Schutz, B F; Scott, J; Scott, S M; Sellers, D; Sengupta, A S; Sentenac, D; Sequino, V; Sergeev, A; Setyawati, Y; Shaddock, D A; Shaffer, T; Shahriar, M S; Shaltev, M; Shapiro, B; Shawhan, P; Sheperd, A; Shoemaker, D H; Shoemaker, D M; Siellez, K; Siemens, X; Sieniawska, M; Sigg, D; Silva, A D; Singer, A; Singer, L P; Singh, A; Singh, R; Singhal, A; Sintes, A M; Slagmolen, B J J; Smith, J R; Smith, N D; Smith, R J E; Son, E J; Sorazu, B; Sorrentino, F; Souradeep, T; Srivastava, A K; Staley, A; Steinke, M; Steinlechner, J; Steinlechner, S; Steinmeyer, D; Stephens, B C; Stevenson, S P; Stone, R; Strain, K A; Straniero, N; Stratta, G; Strauss, N A; Strigin, S; Sturani, R; Stuver, A L; Summerscales, T Z; Sun, L; Sunil, S; Sutton, P J; Swinkels, B L; Szczepańczyk, M J; Tacca, M; Talukder, D; Tanner, D B; Tápai, M; Tarabrin, S P; Taracchini, A; Taylor, R; Theeg, T; Thirugnanasambandam, M P; Thomas, E G; Thomas, M; Thomas, P; Thorne, K A; Thrane, E; Tiwari, S; Tiwari, V; Tokmakov, K V; Toland, K; Tomlinson, C; Tonelli, M; Tornasi, Z; Torres, C V; Torrie, C I; Töyrä, D; Travasso, F; Traylor, G; Trifirò, D; Tringali, M C; Trozzo, L; Tse, M; Turconi, M; Tuyenbayev, D; Ugolini, D; Unnikrishnan, C S; Urban, A L; Usman, S A; Vahlbruch, H; Vajente, G; Valdes, G; Vallisneri, M; van Bakel, N; van Beuzekom, M; van den Brand, J F J; Van Den Broeck, C; Vander-Hyde, D C; van der Schaaf, L; van Heijningen, J V; van Veggel, A A; Vardaro, M; Vass, S; Vasúth, M; Vaulin, R; Vecchio, A; Vedovato, G; Veitch, J; Veitch, P J; Venkateswara, K; Verkindt, D; Vetrano, F; Viceré, A; Vinciguerra, S; Vine, D J; Vinet, J-Y; Vitale, S; Vo, T; Vocca, H; Vorvick, C; Voss, D V; Vousden, W D; Vyatchanin, S P; Wade, A R; Wade, L E; Wade, M; Walker, M; Wallace, L; Walsh, S; Wang, G; Wang, H; Wang, M; Wang, X; Wang, Y; Ward, R L; Warner, J; Was, M; Weaver, B; Wei, L-W; Weinert, M; Weinstein, A J; Weiss, R; Wen, L; Weßels, P; Westphal, T; Wette, K; Whelan, J T; Whiting, B F; Williams, R D; Williamson, A R; Willis, J L; Willke, B; Wimmer, M H; Winkler, W; Wipf, C C; Wittel, H; Woan, G; Woehler, J; Worden, J; Wright, J L; Wu, D S; Wu, G; Yablon, J; Yam, W; Yamamoto, H; Yancey, C C; Yu, H; Yvert, M; Zadrożny, A; Zangrando, L; Zanolin, M; Zendri, J-P; Zevin, M; Zhang, L; Zhang, M; Zhang, Y; Zhao, C; Zhou, M; Zhou, Z; Zhu, X J; Zucker, M E; Zuraw, S E; Zweizig, J; Boyle, M; Hemberger, D; Kidder, L E; Lovelace, G; Ossokine, S; Scheel, M; Szilagyi, B; Teukolsky, S

    2016-06-17

    We report the observation of a gravitational-wave signal produced by the coalescence of two stellar-mass black holes. The signal, GW151226, was observed by the twin detectors of the Laser Interferometer Gravitational-Wave Observatory (LIGO) on December 26, 2015 at 03:38:53 UTC. The signal was initially identified within 70 s by an online matched-filter search targeting binary coalescences. Subsequent off-line analyses recovered GW151226 with a network signal-to-noise ratio of 13 and a significance greater than 5σ. The signal persisted in the LIGO frequency band for approximately 1 s, increasing in frequency and amplitude over about 55 cycles from 35 to 450 Hz, and reached a peak gravitational strain of 3.4_{-0.9}^{+0.7}×10^{-22}. The inferred source-frame initial black hole masses are 14.2_{-3.7}^{+8.3}M_{⊙} and 7.5_{-2.3}^{+2.3}M_{⊙}, and the final black hole mass is 20.8_{-1.7}^{+6.1}M_{⊙}. We find that at least one of the component black holes has spin greater than 0.2. This source is located at a luminosity distance of 440_{-190}^{+180}  Mpc corresponding to a redshift of 0.09_{-0.04}^{+0.03}. All uncertainties define a 90% credible interval. This second gravitational-wave observation provides improved constraints on stellar populations and on deviations from general relativity.

  4. Black hole mass estimate for a sample of radio-loud narrow-line Seyfert 1 galaxies

    CERN Document Server

    Calderone, G; Colpi, M; Dotti, M

    2012-01-01

    We discuss the relationship between a standard Shakura & Sunyaev (1973) accretion disk model and the Big Blue Bump (BBB) observed in Type 1 AGN, and propose a new method to estimate black hole masses. We apply this method to a sample of 23 radio-loud narrow-line Seyfert 1 (RL-NLS1) galaxies, using data from WISE (Wide-field Infrared Survey Explorer), SDSS (Sloan Digital Sky Survey) and GALEX. Our black hole mass estimates are at least a factor $\\sim$6 above previous results based on single epoch virial methods, while the Eddington ratios are correspondingly lower. Hence, the black hole masses of RL-NLS1 galaxies are typically above $10^8 M_{\\sun}$, in agreement with the typical black hole mass of blazars.

  5. Measuring Intermediate-Mass Black-Hole Binaries with Advanced Gravitational Wave Detectors.

    Science.gov (United States)

    Veitch, John; Pürrer, Michael; Mandel, Ilya

    2015-10-02

    We perform a systematic study to explore the accuracy with which the parameters of intermediate-mass black-hole binary systems can be measured from their gravitational wave (GW) signatures using second-generation GW detectors. We make use of the most recent reduced-order models containing inspiral, merger, and ringdown signals of aligned-spin effective-one-body waveforms to significantly speed up the calculations. We explore the phenomenology of the measurement accuracies for binaries with total masses between 50M(⊙) and 500M(⊙) and mass ratios between 0.1 and 1. We find that (i) at total masses below ∼200M(⊙), where the signal-to-noise ratio is dominated by the inspiral portion of the signal, the chirp mass parameter can be accurately measured; (ii) at higher masses, the information content is dominated by the ringdown, and total mass is measured more accurately; (iii) the mass of the lower-mass companion is poorly estimated, especially at high total mass and more extreme mass ratios; and (iv) spin cannot be accurately measured for our injection set with nonspinning components. Most importantly, we find that for binaries with nonspinning components at all values of the mass ratio in the considered range and at a network signal-to-noise ratio of 15, analyzed with spin-aligned templates, the presence of an intermediate-mass black hole with mass >100M(⊙) can be confirmed with 95% confidence in any binary that includes a component with a mass of 130M(⊙) or greater.

  6. Relativistic mergers of black hole binaries have large, similar masses, low spins and are circular

    CERN Document Server

    Amaro-Seoane, Pau

    2015-01-01

    Gravitational waves are a prediction of general relativity, and with ground-based detectors now running in their advanced configuration, we will soon be able to measure them directly for the first time. Binaries of stellar-mass black holes are among the most interesting sources for these detectors. Unfortunately, the many different parameters associated with the problem make it difficult to promptly produce a large set of waveforms for the search in the data stream. To reduce the number of templates to develop, and hence speed up the search, one must restrict some of the physical parameters to a certain range of values predicted by either (electromagnetic) observations or theoretical modeling. This allows one to avoid the need to blindly cover the whole parameter space. In this work we show that "hyperstellar" black holes (HSBs) with masses $30 \\lesssim M_{\\rm BH}/M_{\\odot} \\lesssim 100$, i.e black holes significantly larger than the nominal $10\\,M_{\\odot}$, will have an associated low value for the spin, i.e...

  7. Myers–Perry black holes with scalar hair and a mass gap

    Directory of Open Access Journals (Sweden)

    Yves Brihaye

    2014-12-01

    Full Text Available 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 J1=J2≡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 [1]. 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.

  8. Myers–Perry black holes with scalar hair and a mass gap

    Energy Technology Data Exchange (ETDEWEB)

    Brihaye, Yves [Physique–Mathématique, Universite de Mons-Hainaut, Mons (Belgium); Herdeiro, Carlos; Radu, Eugen [Departamento de Física da Universidade de Aveiro and I3N, Campus de Santiago, 3810-183 Aveiro (Portugal)

    2014-12-12

    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{sub 1}=J{sub 2}≡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 [1]. 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.

  9. The Observed Galactic Annihilation Line. Possible Signature of the Cluster for Accreting Small Mass Black Holes

    CERN Document Server

    Titarchuk, L; Titarchuk, Lev; Chardonnet, Pascal

    2006-01-01

    Compton Gamma Ray Observatory, OSSE, SMM, TGRS, balloon and recent INTEGRAL data reveal a feature of the 0.511 MeV annihilation radiation of the Galactic Center with a flux of approximately 5x 10^{-4}~0.511 MeV photons cm^{-2} s^{-1}. We argue that e+e- pairs can be generated when the X-ray radiation photons and ~10-30 MeV photons interact with each other in the compact region in the proximity of the Galactic Center black hole. In fact, disks formed near black holes of 10^{17} g mass should emit the ~ 10 MeV temperature blackbody radiation. If positron e+ sources are producing about 10^{42} e+ s^{-1} near the Galactic Center they would annihilate on the way out and result in 0.511 MeV emission. We suggest that the annihilation radiation can be an observational consequence of the interaction of the accretion disk radiation of the SMall Mass Black Holes (SMMBHs) with X-ray radiation in the Galactic Center. This is probably the only way to identify and observe these SMMBHs.

  10. Formation of Massive Black Holes in Dense Star Clusters. II. IMF and Primordial Mass Segregation

    CERN Document Server

    Goswami, Sanghamitra; Bierbaum, Matt; Rasio, Frederic A

    2011-01-01

    A promising mechanism to form intermediate-mass black holes (IMBHs) is the runaway merger in dense star clusters, where main-sequence stars collide and form a very massive star (VMS), which then collapses to a black hole. In this paper we study the effects of primordial mass segregation and the importance of the stellar initial mass function (IMF) on the runaway growth of VMSs using a dynamical Monte Carlo code for N-body systems with N as high as 10^6 stars. Our code now includes an explicit treatment of all stellar collisions. We place special emphasis on the possibility of top-heavy IMFs, as observed in some very young massive clusters. We find that both primordial mass segregation and the shape of the IMF affect the rate of core collapse of star clusters and thus the time of the runaway. When we include primordial mass segregation we generally see a decrease in core collapse time (tcc). Moreover, primordial mass segregation increases the average mass in the core, thus reducing the central relaxation time,...

  11. A Measurement of the Black Hole Mass in NGC 1097 Using ALMA

    Science.gov (United States)

    Onishi, K.; Iguchi, S.; Sheth, K.; Kohno, K.

    2015-06-01

    We present an estimate of the mass of the supermassive black hole (SMBH) in the nearby type-1 Seyfert galaxy NGC 1097 using Atacamma Large Millimeter/submillimeter Array (ALMA) observations of dense gas kinematics. Dense molecular gas dynamics are traced with HCN(J=1-0) and HC{{O}+}(J=1-0) emission lines. Assuming a host galaxy inclination of 46{}^\\circ , we derive an SMBH mass, {{M}BH}=1.40-0.32+0.27× {{10}8 }{{M}⊙ }, and an I-band mass to light ratio to be 5.14-0.04+0.03, using HCN(J=1-0). The estimated parameters are consistent between the two emission lines. The measured SMBH mass is in good agreement with the SMBH mass and bulge velocity dispersion relationship. Our result showcases ALMA’s potential for deriving accurate SMBH masses, especially for nearby late-type galaxies. Larger samples and accurate SMBH masses will further elucidate the relationship between the black hole (BH) and host galaxy properties and constrain the coevolutionary growth of galaxies and BHs.

  12. A Measurement of the Black-Hole Mass in NGC 1097 using ALMA

    CERN Document Server

    Onishi, Kyoko; Sheth, Kartik; Kohno, Kotaro

    2015-01-01

    We present an estimate of the mass of the supermassive black hole (SMBH) in the nearby type-1 Seyfert galaxy \\object{NGC 1097} using Atacamma Large Millimeter/Submillimeter Array (ALMA) observations of dense gas kinematics. Dense molecular gas dynamics are traced with ${\\rm HCN} (J=1-0)$ and ${\\rm HCO^{+}} (J=1-0)$ emission lines. Assuming a host galaxy inclination of $46^{\\circ}$, we derive a SMBH mass, $M_{\\rm BH}=1.40^{+0.27}_{-0.32} \\times 10^{8}M_{\\odot}$, and an I-band mass to light ratio to be $5.14^{+0.03}_{-0.04}$, using ${\\rm HCN} (J=1-0)$. The estimated parameters are consistent between the two emission lines. The measured SMBH mass is in good agreement with the SMBH mass and bulge velocity dispersion relationship. Our result showcases ALMA's potential for deriving accurate SMBH masses, especially for nearby late-type galaxies. Larger samples and accurate SMBH masses will further elucidate the relationship between the black hole (BH) and host galaxy properties and constrain the coevolutionary growt...

  13. Magnetic massive stars as progenitors of "heavy" stellar-mass black holes

    CERN Document Server

    Petit, V; MacInnis, R; Cohen, D H; Townsend, R H D; Wade, G A; Thomas, S L; Owocki, S P; Puls, J; ud-Doula, J A

    2016-01-01

    The groundbreaking detection of gravitational waves produced by the inspiralling and coalescence of the black hole (BH) binary GW150914 confirms the existence of "heavy" stellar-mass BHs with masses >25 Msun. Initial modelling of the system by Abbott et al. (2016a) supposes that the formation of black holes with such large masses from the evolution of single massive stars is only feasible if the wind mass-loss rates of the progenitors were greatly reduced relative to the mass-loss rates of massive stars in the Galaxy, concluding that heavy BHs must form in low-metallicity (Z 25 Msun such as those inferred to compose GW150914, could be the natural end-point of evolution of magnetic massive stars in a solar-metallicity environment. Using the MESA code, we developed a new grid of single, non-rotating, solar metallicity evolutionary models for initial ZAMS masses from 40-80 Msun that include, for the first time, the quenching of the mass loss due to a realistic dipolar surface magnetic field. The new models predi...

  14. N-body modeling of globular clusters: Masses, mass-to-light ratios and intermediate-mass black holes

    CERN Document Server

    Baumgardt, Holger

    2016-01-01

    We have determined the masses and mass-to-light ratios of 50 Galactic globular clusters by comparing their velocity dispersion and surface brightness profiles against a large grid of 900 N-body simulations of star clusters of varying initial concentration, size and central black hole mass fraction. Our models follow the evolution of the clusters under the combined effects of stellar evolution and two-body relaxation allowing us to take the effects of mass segregation and energy equipartition between stars self-consistently into account. For a subset of 16 well observed clusters we also derive their kinematic distances. We find an average mass-to-light ratio of Galactic globular clusters of $=1.98 \\pm 0.03$, which agrees very well with the expected M/L ratio if the initial mass function of the clusters was a standard Kroupa or Chabrier mass function. We do not find evidence for a decrease of the average mass-to-light ratio with metallicity. The surface brightness and velocity dispersion profiles of most globul...

  15. Do Circumnuclear Dense Gas Disks Drive Mass Accretion onto Supermassive Black Holes?

    Science.gov (United States)

    Izumi, Takuma; Kawakatu, Nozomu; Kohno, Kotaro

    2016-08-01

    We present a positive correlation between the mass of dense molecular gas ({M}{{dense}}) of ˜100 pc scale circumnuclear disks (CNDs) and the black hole mass accretion rate ({\\dot{M}}{{BH}}) in a total of 10 Seyfert galaxies, based on data compiled from the literature and an archive (median aperture θ med = 220 pc). A typical {M}{{dense}} of CNDs is 107-8 {M}⊙ , estimated from the luminosity of the dense gas tracer, the HCN(1-0) emission line. Because dense molecular gas is the site of star formation, this correlation is virtually equivalent to the one between the nuclear star-formation rate and {\\dot{M}}{{BH}} revealed previously. Moreover, the {M}{{dense}}{--}{\\dot{M}}{{BH}} correlation was tighter for CND-scale gas than for the gas on kiloparsec or larger scales. This indicates that CNDs likely play an important role in fueling black holes, whereas greater than kiloparesec scale gas does not. To demonstrate a possible approach for studying the CND-scale accretion process with the Atacama Large Millimeter/submillimeter Array, we used a mass accretion model where angular momentum loss due to supernova explosions is vital. Based on the model prediction, we suggest that only the partial fraction of the mass accreted from the CND ({\\dot{M}}{{acc}}) is consumed as {\\dot{M}}{{BH}}. However, {\\dot{M}}{{acc}} agrees well with the total nuclear mass flow rate (i.e., {\\dot{M}}{{BH}} + outflow rate). Although these results are still tentative with large uncertainties, they support the view that star formation in CNDs can drive mass accretion onto supermassive black holes in Seyfert galaxies.

  16. Inference on gravitational waves from coalescences of stellar-mass compact objects and intermediate-mass black holes

    Science.gov (United States)

    Haster, Carl-Johan; Wang, Zhilu; Berry, Christopher P. L.; Stevenson, Simon; Veitch, John; Mandel, Ilya

    2016-04-01

    Gravitational waves from coalescences of neutron stars or stellar-mass black holes into intermediate-mass black holes (IMBHs) of ≳100 solar masses represent one of the exciting possible sources for advanced gravitational-wave detectors. These sources can provide definitive evidence for the existence of IMBHs, probe globular-cluster dynamics, and potentially serve as tests of general relativity. We analyse the accuracy with which we can measure the masses and spins of the IMBH and its companion in intermediate-mass-ratio coalescences. We find that we can identify an IMBH with a mass above 100 M⊙ with 95 per cent confidence provided the massive body exceeds 130 M⊙. For source masses above ˜200 M⊙, the best measured parameter is the frequency of the quasi-normal ringdown. Consequently, the total mass is measured better than the chirp mass for massive binaries, but the total mass is still partly degenerate with spin, which cannot be accurately measured. Low-frequency detector sensitivity is particularly important for massive sources, since sensitivity to the inspiral phase is critical for measuring the mass of the stellar-mass companion. We show that we can accurately infer source parameters for cosmologically redshifted signals by applying appropriate corrections. We investigate the impact of uncertainty in the model gravitational waveforms and conclude that our main results are likely robust to systematics.

  17. Charged Lifshitz Black Holes

    OpenAIRE

    Dehghani, M. H.; Pourhasan, R.; Mann, R. B.

    2011-01-01

    We investigate modifications of the Lifshitz black hole solutions due to the presence of Maxwell charge in higher dimensions for arbitrary $z$ and any topology. We find that the behaviour of large black holes is insensitive to the topology of the solutions, whereas for small black holes significant differences emerge. We generalize a relation previously obtained for neutral Lifshitz black branes, and study more generally the thermodynamic relationship between energy, entropy, and chemical pot...

  18. Penrose inequalities and a positive mass theorem for charged black holes in higher dimension

    CERN Document Server

    de Lima, Levi Lopes; Lozório, Weslley; Silva, Juscelino

    2014-01-01

    We use the inverse mean curvature flow to establish Penrose-type inequalities for time-symmetric Einstein-Maxwell initial data sets which can be suitably embedded as a hypersurface in Euclidean space $\\mathbb R^{n+1}$, $n\\geq 3$. In particular, we prove a positive mass theorem for this class of charged black holes. As an application we show that the conjectured upper bound for the area in terms of the mass and the charge, which in dimension $n=3$ is relevant in connection with the Cosmic Censorship Conjecture, always holds under the natural assumption that the horizon is stable as a minimal hypersurface.

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

    OpenAIRE

    Laor, Ari

    2001-01-01

    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 si...

  20. Evidence for Broad-Line Region Outflows and Their Impact on Black Hole Mass Measurements

    DEFF Research Database (Denmark)

    Denney, K. D.; Assef, R. J.; Horne, K.

    2012-01-01

    could not be fully and accurately interpreted from the 1D velocity-resolved reverberation signal. From the VDM, an outflow component to the emission remains possible but appears to be in addition to an underlying, disk-like BLR structure consistent in size with the measured reverberation lag. The black...... hole (BH) mass derived from this data is therefore secure from any uncertainties possibly derived from gravitationally unbound gas contributing to the emission. Additionally, we demonstrate that BLR emission from the C IV ¿1549 broad emission line can reliably be used as a virial BH mass estimator...

  1. Why do galaxies stop forming stars? I. The passive fraction - black hole mass relation for central galaxies

    CERN Document Server

    Bluck, Asa F L; Patton, David R; Simard, Luc; Mendel, J Trevor; Teimoorinia, Hossein; Moreno, Jorge; Starkenburg, Else

    2014-01-01

    We derive the dependence of the fraction of passive central galaxies on the mass of their supermassive black holes for a sample of over 400,000 SDSS galaxies at z < 0.2. Our large sample contains galaxies in a wide range of environments, with stellar masses 8 < log(M*/Msun) < 12, spanning the entire morphological spectrum from pure disks to spheroids. We derive estimates for the black hole masses from measured central velocity dispersions and bulge masses, using a variety of published empirical relationships. We find a very strong dependence of the passive fraction on black hole mass, which is largely unaffected by the details of the black hole mass estimate. Moreover, the passive fraction relationship with black hole mass remains strong and tight even at fixed values of galaxy stellar mass (M*), dark matter halo mass (Mhalo), and bulge-to-total stellar mass ratio (B/T). Whereas, the passive fraction dependence on M*, Mhalo and B/T is weak at fixed MBH. These observations show that, for central galax...

  2. Exploring mass-scaling physics and outflow geometry in accreting black holes

    Science.gov (United States)

    Connors, Riley Michael Thomas

    2017-01-01

    One of the main tasks facing studies of black hole accretion in both black hole X-ray binaries (XRB) and Active Galactic Nuclei (AGN) is to break spectral model-fitting degeneracies. We explore two methods of simultaneous spectral modelling to reduce these degeneracies: (a) simultaneous fitting of XRBs and AGN, and (b) folding in timing properties in a novel way to better understand the outflow evolution of XRBs during outburst.It is a long-standing idea that AGN are scaled up versions of XRBs, such that the physics of accretion cares only about accretion rate, and not the black hole mass. We show that this principle of scale-invariance may provide us with a way to break degeneracies in broadband spectral modelling of both XRBs and AGN, focusing primarily on low-luminosity sources where degeneracies are more prevalent. We simultaneously model the broadband spectra of the two most quiescent (LX ~ 10-9 LEdd) accreting black holes on opposite ends of the mass scale, the XRB A0620-00 and Sgr A*, the Galactic centre supermassive black hole (during bright flaring). We use an outflow-dominated model capable of reproducing the broadband spectrum from radio to X-ray frequencies, co-evolving parameters that are representative of the mass-scaling properties. Such a method reduces the degeneracies in our model parameters, contributing to answering this question regarding the dominant emission mechanisms.We adopt a similar technique to investigate how spatial parameters of an XRB outflow can be better understood by tracking our model parameters as a function of the XRB variability properties during outburst, focusing in particular on GX 339-4. I shall discuss how utilising a novel characterisation of the timing properties of XRBs allows us to do this in a simple, quantitative way.We are currently developing our models further to incorporate the most up-to-date disc reflection routines in order to describe the jet/disc interaction more accurately. I shall briefly discuss this

  3. Inference on gravitational waves from coalescences of stellar-mass compact objects and intermediate-mass black holes

    CERN Document Server

    Haster, Carl-Johan; Berry, Christopher P L; Stevenson, Simon; Veitch, John; Mandel, Ilya

    2015-01-01

    Gravitational waves from coalescences of neutron stars or stellar-mass black holes into intermediate-mass black holes (IMBHs) of $\\gtrsim 100$ solar masses represent one of the exciting possible sources for advanced gravitational-wave detectors. These sources can provide definitive evidence for the existence of IMBHs, probe globular-cluster dynamics, and potentially serve as tests of general relativity. We analyse the accuracy with which we can measure the masses and spins of the IMBH and its companion in intermediate-mass ratio coalescences. We find that we can identify an IMBH with a mass above $100 ~ M_\\odot$ with $95\\%$ confidence provided the massive body exceeds $130 ~ M_\\odot$. For source masses above $\\sim200 ~ M_\\odot$, the best measured parameter is the frequency of the quasi-normal ringdown. Consequently, the total mass is measured better than the chirp mass for massive binaries, but the total mass is still partly degenerate with spin, which cannot be accurately measured. Low-frequency detector sen...

  4. Mid-Infrared Selected Quasars I: Virial Black Hole Mass and Eddington Ratios

    CERN Document Server

    Dai, Y Sophia; Bergeron, Jacqueline; Fazio, Giovanni G; Huang, Jia-Sheng; Wilkes, Belinda J; Willmer, Christopher N A; Omont, Alain; Papovich, Casey

    2014-01-01

    We provide a catalog of 391 mid-infrared-selected (MIR, 24$\\mu$m) broad-emission-line (BEL, type 1) quasars in the 22 deg$^2$ SWIRE Lockman Hole field. This quasar sample is selected in the MIR from Spitzer MIPS with $S_{\\rm 24} > 400\\mu$Jy, jointly with an optical magnitude limit of r (AB) $ 19.1$. We then investigate the continuum luminosity and line profiles of these MIR quasars, and estimate their virial black hole masses and the Eddington ratios. The SMBH mass shows evidence of downsizing, though the Eddington ratios remain constant at $1 < z < 4$. Compared to point sources in the same redshift range, extended sources at $z < 1$ show systematically lower Eddington ratios. The catalog and spectra are publicly available online.

  5. Relativistic mergers of black hole binaries have large, similar masses, low spins and are circular

    Science.gov (United States)

    Amaro-Seoane, Pau; Chen, Xian

    2016-05-01

    Gravitational waves are a prediction of general relativity, and with ground-based detectors now running in their advanced configuration, we will soon be able to measure them directly for the first time. Binaries of stellar-mass black holes are among the most interesting sources for these detectors. Unfortunately, the many different parameters associated with the problem make it difficult to promptly produce a large set of waveforms for the search in the data stream. To reduce the number of templates to develop, one must restrict some of the physical parameters to a certain range of values predicted by either (electromagnetic) observations or theoretical modelling. In this work, we show that `hyperstellar' black holes (HSBs) with masses 30 ≲ MBH/M⊙ ≲ 100, i.e black holes significantly larger than the nominal 10 M⊙, will have an associated low value for the spin, i.e. a < 0.5. We prove that this is true regardless of the formation channel, and that when two HSBs build a binary, each of the spin magnitudes is also low, and the binary members have similar masses. We also address the distribution of the eccentricities of HSB binaries in dense stellar systems using a large suite of three-body scattering experiments that include binary-single interactions and long-lived hierarchical systems with a highly accurate integrator, including relativistic corrections up to O(1/c^5). We find that most sources in the detector band will have nearly zero eccentricities. This correlation between large, similar masses, low spin and low eccentricity will help to accelerate the searches for gravitational-wave signals.

  6. Stellar Populations across the Black Hole Mass-Velocity Dispersion Relation

    Science.gov (United States)

    Martín-Navarro, Ignacio; Brodie, Jean P.; van den Bosch, Remco C. E.; Romanowsky, Aaron J.; Forbes, Duncan A.

    2016-11-01

    Coevolution between supermassive black holes (BH) and their host galaxies is universally adopted in models for galaxy formation. In the absence of feedback from active galactic nuclei (AGNs), simulated massive galaxies keep forming stars in the local universe. From an observational point of view, however, such coevolution remains unclear. We present a stellar population analysis of galaxies with direct BH mass measurements and the BH mass-σ relation as a working framework. We find that over-massive BH galaxies, i.e., galaxies lying above the best-fitting BH mass-σ line, tend to be older and more α-element-enhanced than under-massive BH galaxies. The scatter in the BH mass-σ-[α/Fe] plane is significantly lower than that in the standard BH mass-σ relation. We interpret this trend as an imprint of AGN feedback on the star formation histories of massive galaxies.

  7. When Charged Black Holes Merge

    Science.gov (United States)

    Kohler, Susanna

    2016-08-01

    Most theoretical models assume that black holes arent charged. But a new study shows that mergers of charged black holes could explain a variety of astrophysical phenomena, from fast radio bursts to gamma-ray bursts.No HairThe black hole no hair theorem states that all black holes can be described by just three things: their mass, their spin, and their charge. Masses and spins have been observed and measured, but weve never measured the charge of a black hole and its widely believed that real black holes dont actually have any charge.That said, weve also never shown that black holes dont have charge, or set any upper limits on the charge that they might have. So lets suppose, for a moment, that its possible for a black hole to be charged. How might that affect what we know about the merger of two black holes? A recent theoretical study by Bing Zhang (University of Nevada, Las Vegas) examines this question.Intensity profile of a fast radio burst, a sudden burst of radio emission that lasts only a few milliseconds. [Swinburne Astronomy Productions]Driving TransientsZhangs work envisions a pair of black holes in a binary system. He argues that if just one of the black holes carries charge possibly retained by a rotating magnetosphere then it may be possible for the system to produce an electromagnetic signal that could accompany gravitational waves, such as a fast radio burst or a gamma-ray burst!In Zhangs model, the inspiral of the two black holes generates a global magnetic dipole thats perpendicular to the plane of the binarys orbit. The magnetic flux increases rapidly as the separation between the black holes decreases, generating an increasingly powerful magnetic wind. This wind, in turn, can give rise to a fast radio burst or a gamma-ray burst, depending on the value of the black holes charge.Artists illustration of a short gamma-ray burst, thought to be caused by the merger of two compact objects. [ESO/A. Roquette]Zhang calculates lower limits on the charge

  8. Resource Letter BH-2: Black Holes

    CERN Document Server

    Gallo, Elena

    2008-01-01

    This resource letter is designed to guide students, educators, and researchers through (some of) the literature on black holes. Both the physics and astrophysics of black holes are discussed. Breadth has been emphasized over depth, and review articles over primary sources. We include resources ranging from non-technical discussions appropriate for broad audiences to technical reviews of current research. Topics addressed include classification of stationary solutions, perturbations and stability of black holes, numerical simulations, collisions, the production of gravity waves, black hole thermodynamics and Hawking radiation, quantum treatments of black holes, black holes in both higher and lower dimensions, and connections to nuclear and condensed matter physics. On the astronomical end, we also cover the physics of gas accretion onto black holes, relativistic jets, gravitationally red-shifted emission lines, evidence for stellar-mass black holes in binary systems and super-massive black holes at the centers...

  9. Simultaneous Ultraviolet and Optical Emission-line Profiles of Quasars: Implications for Black Hole Mass Determination

    CERN Document Server

    Ho, Luis C; Dong, Xiao-Bo; Greene, Jenny E; Ponti, Gabriele

    2012-01-01

    The X-shooter instrument on the VLT was used to obtain spectra of seven moderate-redshift quasars simultaneously covering the spectral range 3000 Ang to 2.5 microns. At z ~ 1.5, most of the prominent broad emission lines in the ultraviolet to optical region are captured in their rest frame. We use this unique dataset, which mitigates complications from source variability, to intercompare the line profiles of C IV 1549, C III] 1909, Mg II 2800, and Halpha and evaluate their implications for black hole mass estimation. We confirm that Mg II and the Balmer lines share similar kinematics and that they deliver mutually consistent black hole mass estimates with minimal internal scatter (< 0.1 dex) using the latest virial mass estimators. Although no virial mass formalism has yet been calibrated for C III], this line does not appear promising for such an application because of the large spread of its velocity width compared to lines of both higher and lower ionization; part of the discrepancy may be due to the di...

  10. Intermediate$-$mass black holes from Population III remnants in the first galactic nuclei

    CERN Document Server

    Ryu, Taeho; Perna, Rosalba; Haiman, Zoltan

    2016-01-01

    We report the formation of intermediate-mass black holes (IMBHs) in suites of numerical $N$-body simulations of Population III remnant black holes (BHs) embedded in gas-rich protogalaxies at redshifts $z\\gtrsim10$. We model the effects of gas drag on the BHs' orbits, and allow BHs to grow via gas accretion, including a mode of hyper-Eddington accretion in which photon trapping and rapid gas inflow suppress any negative radiative feedback. Most initial BH configurations lead to the formation of one (but never more than one) IMBH in the center of the protogalaxy, reaching a mass of $10^{3-5}\\mathrm{M}_{\\odot}$ through hyper-Eddington growth. Our results suggest a viable pathway to forming the earliest massive BHs in the centers of early galaxies. We also find that the nuclear IMBH typically captures a stellar-mass BH companion, making these systems observable in gravitational waves as extreme mass-ratio inspirals (EMRIs) with \\textit{eLISA}.

  11. Kicking massive black holes off clusters: Intermediate-mass ratio inspirals

    CERN Document Server

    Konstantinidis, Symeon; Kokkotas, Kostas D

    2011-01-01

    Contrary to supermassive and stellar-mass black holes (SBHs), the existence of intermediate-mass black holes (IMBHs) with masses ranging between 100 and 10,000 Msun has not yet been confirmed. The main problem in the detection is that the innermost stellar kinematics of globular clusters (GCs), the natural loci to IMBHs, are very difficult to resolve. However, if IMBHs reside in the center of GCs, a possibility is that they interact dynamically with their enviroment. A binary formed with the IMBH and a compact object of the GC would naturally lead to a prominent source of gravitational radiation, detectable with future observatories. We run for the first time direct-summation integrations of GCs with an IMBH including the dynamical evolution of the IMBH with the stellar system and relativistic effects, such as energy loss in gravitational waves (GWs) and periapsis shift, and gravitational recoil. We find in one of our models an intermediate-mass ratio inspiral (IMRI), which leads to a merger with a recoiling ...

  12. Black-hole mass estimates for a homogeneous sample of bright flat-spectrum radio quasars

    CERN Document Server

    Castignani, Gianluca; Lapi, Andrea; De Zotti, Gianfranco; Celotti, Annalisa; Danese, Luigi

    2013-01-01

    We have selected a complete sample of flat-spectrum radio quasars (FSRQs) from the WMAP 7-yr catalog within the SDSS area, all with measured redshift, and have compared the black hole mass estimates based on fitting a standard accretion disk model to the `blue bump' with those obtained from the commonly used single epoch virial method. The sample comprises 79 objects with a flux density limit of 1 Jy at 23 GHz, 54 of which (68%) have a clearly detected `blue bump'. Thirty-four of the latter have, in the literature, black hole mass estimates obtained with the virial method. The mass estimates obtained from the two methods are well correlated. If the calibration factor of the virial relation is set to $f=4.5$, well within the range of recent estimates, the mean logarithmic ratio of the two mass estimates is equal to zero with a dispersion close to the estimated uncertainty of the virial method. The fact that the two independent methods agree so closely in spite of the potentially large uncertainties associated ...

  13. Inspiral, merger and ringdown of unequal mass black hole binaries: a multipolar analysis

    CERN Document Server

    Berti, E; Cardoso, V; González, J A; Hannam, M; Husa, S; Sperhake, U; Berti, Emanuele; Bruegmann, Bernd; Cardoso, Vitor; Gonzalez, Jose A.; Hannam, Mark; Husa, Sascha; Sperhake, Ulrich

    2007-01-01

    We study the inspiral, merger and ringdown of unequal mass black hole binaries by analyzing a catalogue of numerical simulations for seven different values of the mass ratio (from q=M2/M1=1 to q=4). We compare numerical and Post-Newtonian results by projecting the waveforms onto spin-weighted spherical harmonics, characterized by angular indices (l,m). We find that the Post-Newtonian equations predict remarkably well the relation between the wave amplitude and the orbital frequency for each (l,m), and that the convergence of the Post-Newtonian series to the numerical results is non-monotonic. To leading order the total energy emitted in the merger phase scales like eta^2 and the spin of the final black hole scales like eta, where eta=q/(1+q)^2 is the symmetric mass ratio. We study the multipolar distribution of the radiation, finding that odd-l multipoles are suppressed in the equal mass limit. Higher multipoles carry a larger fraction of the total energy as q increases. We introduce and compare three differe...

  14. Prospects for intermediate mass black hole binary searches with advanced gravitational-wave detectors

    CERN Document Server

    Mazzolo, G; Drago, M; Necula, V; Pankow, C; Prodi, G A; Re, V; Tiwari, V; Vedovato, G; Yakushin, I; Klimenko, S

    2014-01-01

    We estimated the sensitivity of the upcoming advanced, ground-based gravitational-wave observatories (the upgraded LIGO and Virgo and the KAGRA interferometers) to coalescing intermediate mass black hole binaries (IMBHB). We added waveforms modeling the gravitational radiation emitted by IMBHBs to detectors' simulated data and searched for the injected signals with the coherent WaveBurst algorithm. The tested binary's parameter space covers non-spinning IMBHBs with source-frame total masses between 50 and 1050 $\\text{M}_{\\odot}$ and mass ratios between $1/6$ and 1$\\,$. We found that advanced detectors could be sensitive to these systems up to a range of a few Gpc. A theoretical model was adopted to estimate the expected observation rates, yielding up to a few tens of events per year. Thus, our results indicate that advanced detectors will have a reasonable chance to collect the first direct evidence for intermediate mass black holes and open a new, intriguing channel for probing the Universe over cosmological...

  15. Extremal Hairy Black Holes

    CERN Document Server

    Gonzalez, P A; Saavedra, Joel; Vasquez, Yerko

    2014-01-01

    We consider a gravitating system consisting of a scalar field minimally coupled to gravity with a self-interacting potential and an U(1) electromagnetic field. Solving the coupled Einstein-Maxwell-scalar system we find exact hairy charged black hole solutions with the scalar field regular everywhere. We go to the zero temperature limit and we study the effect of the scalar field on the near horizon geometry of an extremal black hole. We find that except a critical value of the charge of the black hole there is also a critical value of the charge of the scalar field beyond of which the extremal black hole is destabilized. We study the thermodynamics of these solutions and we find that if the space is flat then at low temperature the Reissner-Nordstr\\"om black hole is thermodynamically preferred, while if the space is AdS the hairy charged black hole is thermodynamically preferred at low temperature.

  16. Astrophysical black holes

    CERN Document Server

    Gorini, Vittorio; Moschella, Ugo; Treves, Aldo; Colpi, Monica

    2016-01-01

    Based on graduate school lectures in contemporary relativity and gravitational physics, this book gives a complete and unified picture of the present status of theoretical and observational properties of astrophysical black holes. The chapters are written by internationally recognized specialists. They cover general theoretical aspects of black hole astrophysics, the theory of accretion and ejection of gas and jets, stellar-sized black holes observed in the Milky Way, the formation and evolution of supermassive black holes in galactic centers and quasars as well as their influence on the dynamics in galactic nuclei. The final chapter addresses analytical relativity of black holes supporting theoretical understanding of the coalescence of black holes as well as being of great relevance in identifying gravitational wave signals. With its introductory chapters the book is aimed at advanced graduate and post-graduate students, but it will also be useful for specialists.

  17. As above, so below: exploiting mass scaling in black hole accretion to break degeneracies in spectral interpretation

    CERN Document Server

    Markoff, Sera; Gallo, Elena; Hynes, Robert; Wilms, Jörn; Plotkin, Richard M; Maitra, Dipankar; Silva, Catia V; Drappeau, Samia

    2015-01-01

    Over the last decade, the evidence is mounting that several aspects of black hole accretion physics proceed in a mass-invariant way. One of the best examples of this scaling is the empirical "Fundamental Plane of Black Hole Accretion" relation linking mass, radio and X-ray luminosity over eight orders of magnitude in black hole mass. The currently favored theoretical interpretation of this relation is that the physics governing power output in weakly accreting black holes depends more on relative accretion rate than on mass. In order to test this theory, we explore whether a mass-invariant approach can simultaneously explain the broadband spectral energy distributions from two black holes at opposite ends of the mass scale but at similar Eddington accretion fractions. We find that the same model, with the same value of several fitted physical parameters expressed in mass-scaling units to enforce self-similarity, can provide a good description of two datasets from V404 Cyg and M81*, a stellar and supermassive ...

  18. Perturbations around black holes

    CERN Document Server

    Wang, B

    2005-01-01

    Perturbations around black holes have been an intriguing topic in the last few decades. They are particularly important today, since they relate to the gravitational wave observations which may provide the unique fingerprint of black holes' existence. Besides the astrophysical interest, theoretically perturbations around black holes can be used as testing grounds to examine the proposed AdS/CFT and dS/CFT correspondence.

  19. Quasistars: Accreting black holes inside massive envelopes

    CERN Document Server

    Begelman, Mitchell C; Armitage, Philip J

    2007-01-01

    We study the structure and evolution of "quasistars," accreting black holes embedded within massive hydrostatic gaseous envelopes. These configurations may model the early growth of supermassive black hole seeds. The accretion rate onto the black hole adjusts so that the luminosity carried by the convective envelope equals the Eddington limit for the total mass. This greatly exceeds the Eddington limit for the black hole mass alone, leading to rapid growth of the black hole. We use analytic models and numerical stellar structure calculations to study the structure and evolution of quasistars. We derive analytically the scaling of the photospheric temperature with the black hole mass and envelope mass, and show that it decreases with time as the black hole mass increases. Once the photospheric temperature becomes lower than 10000 K, the photospheric opacity drops precipitously and the photospheric temperature hits a limiting value, analogous to the Hayashi track for red giants and protostars, below which no hy...

  20. The head-on collision of two equal mass black holes numerical methods

    CERN Document Server

    Anninos, P; Seidel, E; Smarr, L L; Suen, W M; Anninos, Peter; Hobill, David; Seidel, Edward; Smarr, Larry; Suen, Wai Mo

    1994-01-01

    The head-on collision of two nonrotating axisymmetric equal mass black holes is treated numerically. We take as initial data the single parameter family of time-symmetric solutions discovered by Misner which consists of two Einstein-Rosen bridges that can be placed arbitrarily distant from one another. A number of problems associated with previous attempts to evolve these data sets have been overcome. In this article, we discuss our choices for coordinate systems, gauges, and the numerical algorithms that we have developed to evolve this system.

  1. Stellar mass black holes in star clusters: gravitational wave emission and detection rates

    OpenAIRE

    Banerjee, Sambaran

    2011-01-01

    We investigate the dynamics of stellar-mass black holes (BH) in star clusters focusing on the dynamical formation of BH-BH binaries, which are very important sources of gravitational waves (GW). We examine the properties of these BH-BH binaries through direct N-body computations of Plummer clusters, having initially N(0) = 5 X 10^4, typically a few of them dynamically harden to the extent that they can merge via GW emission within the cluster. Also, for each of such clusters, there are a few ...

  2. On the possibilities of mass loss from an advective accretion disc around stationary black holes

    CERN Document Server

    Das, Santabrata; Nandi, Anuj; Sarkar, Biplob

    2014-01-01

    We study the coupled disc-jet system around the black hole where the outflow solutions are obtained in terms of the inflow parameters. We observe that an advective accretion disc can eject outflows/jets for wide range of viscosity parameter. However, such possibility is reduced if the cooling is active as the energy dissipative process inside the disc. For mass outflow, we obtain the parameter space spanned by the inflow angular momentum and the viscosity in terms of cooling and quantify the limits of viscosity parameter.

  3. Intermediate-mass-ratio black-hole binaries: numerical relativity meets perturbation theory.

    Science.gov (United States)

    Lousto, Carlos O; Nakano, Hiroyuki; Zlochower, Yosef; Campanelli, Manuela

    2010-05-28

    We study black-hole binaries in the intermediate-mass-ratio regime 0.01≲q≲0.1 with a new technique that makes use of nonlinear numerical trajectories and efficient perturbative evolutions to compute waveforms at large radii for the leading and nonleading (ℓ, m) modes. As a proof-of-concept, we compute waveforms for q=1/10. We discuss applications of these techniques for LIGO and VIRGO data analysis and the possibility that our technique can be extended to produce accurate waveform templates from a modest number of fully nonlinear numerical simulations.

  4. On the Correlation between Radio Properties and Black Hole Mass of Quasars

    Institute of Scientific and Technical Information of China (English)

    Xue-Guang Zhang; Ting-Gui Wang; You-Jun Lu

    2003-01-01

    The question whether the radio properties of quasars are related tothe mass of the central black hole or the accretion rate is important for our un-derstanding of the formation of relativistic jets, but no consensus has been reachedfrom statistical analyses. Using two large quasar samples, one radio-selected, oneoptical-selected, we re-examined these relations and find that previous differencesbetween radio- and optical- selected samples can be ascribed, at least partly, to theeffect of the narrow line component. All previous claimed correlations are muchweaker, if exist at all.

  5. A nonsingular rotating black hole

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Sushant G. [Jamia Millia Islamia, Centre for Theoretical Physics, New Delhi (India); University of KwaZulu-Natal, Astrophysics and Cosmology Research Unit, School of Mathematical Sciences, Durban (South Africa)

    2015-11-15

    The spacetime singularities in classical general relativity are inevitable, as predicated by the celebrated singularity theorems. However, it is a general belief that singularities do not exist in Nature and that they are the limitations of the general relativity. In the absence of a welldefined quantum gravity, models of regular black holes have been studied. We employ a probability distribution inspired mass function m(r) to replace the Kerr black hole mass M to represent a nonsingular rotating black hole that is identified asymptotically (r >> k, k > 0 constant) exactly as the Kerr-Newman black hole, and as the Kerr black hole when k = 0. The radiating counterpart renders a nonsingular generalization of Carmeli's spacetime as well as Vaidya's spacetime, in the appropriate limits. The exponential correction factor changing the geometry of the classical black hole to remove the curvature singularity can also be motivated by quantum arguments. The regular rotating spacetime can also be understood as a black hole of general relativity coupled to nonlinear electrodynamics. (orig.)

  6. Slowly balding black holes

    CERN Document Server

    Lyutikov, Maxim

    2011-01-01

    The "no hair" theorem, a key result in General Relativity, states that an isolated black hole is defined by only three parameters: mass, angular momentum, and electric charge; this asymptotic state is reached on a light-crossing time scale. We find that the "no hair" theorem is not formally applicable for black holes formed from collapse of a rotating neutron star. Rotating neutron stars can self-produce particles via vacuum breakdown forming a highly conducting plasma magnetosphere such that magnetic field lines are effectively "frozen-in" the star both before and during collapse. In the limit of no resistivity, this introduces a topological constraint which prohibits the magnetic field from sliding off the newly-formed event horizon. As a result, during collapse of a neutron star into a black hole, the latter conserves the number of magnetic flux tubes $N_B = e \\Phi_\\infty /(\\pi c \\hbar)$, where $\\Phi_\\infty \\approx 2 \\pi^2 B_{NS} R_{NS}^3 /(P_{\\rm NS} c)$ is the initial magnetic flux through the hemisphere...

  7. Linear dilaton black holes

    CERN Document Server

    Clément, G; Leygnac, C; Clement, Gerard; Gal'tsov, Dmitri; Leygnac, Cedric

    2003-01-01

    We present new solutions to Einstein-Maxwell-dilaton-axion (EMDA) gravity in four dimensions describing black holes which asymptote to the linear dilaton background. In the non-rotating case they can be obtained as the limiting geometry of dilaton black holes. The rotating solutions (possibly endowed with a NUT parameter) are constructed using a generating technique based on the Sp(4,R) duality of the EMDA system. In a certain limit (with no event horizon present) our rotating solutions coincide with supersymmetric Israel-Wilson-Perjes type dilaton-axion solutions. In presence of an event horizon supersymmetry is broken. The temperature of the static black holes is constant, and their mass does not depend on it, so the heat capacity is zero. We investigate geodesics and wave propagation in these spacetimes and find superradiance in the rotating case. Because of the non-asymptotically flat nature of the geometry, certain modes are reflected from infinity, in particular, all superradiant modes are confined. Thi...

  8. Searching for intermediate-mass black holes in globular clusters with gravitational microlensing

    CERN Document Server

    Kains, N; Sahu, K C; Calamida, A

    2016-01-01

    We discuss the potential of the gravitational microlensing method as a unique tool to detect unambiguous signals caused by intermediate-mass black holes in globular clusters. We select clusters near the line of sight to the Galactic Bulge and the Small Magellanic Cloud, estimate the density of background stars for each of them, and carry out simulations in order to estimate the probabilities of detecting the astrometric signatures caused by black hole lensing. We find that for several clusters, the probability of detecting such an event is significant with available archival data from the Hubble Space Telescope. Specifically, we find that M 22 is the cluster with the best chances of yielding an IMBH detection via astrometric microlensing. If M 22 hosts an IMBH of mass $10^5M_\\odot$, then the probability that at least one star will yield a detectable signal over an observational baseline of 20 years is $\\sim 86\\%$, while the probability of a null result is around $14\\%$. For an IMBH of mass $10^6M_\\odot$, the ...

  9. The Megamaser Cosmology Project.IX. Black hole masses for three maser galaxies

    CERN Document Server

    Gao, F; Reid, M J; Condon, J J; Greene, J E; Henkel, C; Impellizzeri, C M V; Lo, K Y; Kuo, C Y; Pesce, D W; Wagner, J; Zhao, W

    2016-01-01

    As part of the Megamaser Cosmology Project (MCP), we present VLBI maps of nuclear water masers toward five galaxies. The masers originate in sub-parsec circumnuclear disks. For three of the galaxies, we fit Keplerian rotation curves to estimate their supermassive black hole (SMBH) masses, and determine (2.9 $\\pm$ 0.3) $\\times~10^{6}M_\\odot$ for J0437+2456, (1.7 $\\pm$ 0.1) $\\times~10^{7}M_\\odot$ for ESO 558$-$G009, and (1.1 $\\pm$ 0.2) $\\times~10^{7}M_\\odot$ for NGC 5495. In the other two galaxies, Mrk 1029 and NGC 1320, the geometry and dynamics are more complicated and preclude robust black hole mass estimates. Including our new results, we compiled a list of 15 VLBI-confirmed disk maser galaxies with robust SMBH mass measurements. With this sample, we confirm the empirical relation of $R_{out} \\propto 0.3 M_{SMBH}$ reported in Wardle & Yusef-Zadeh (2012). We also find a tentative correlation between maser disk outer radii and WISE luminosity. We find no correlations of maser disk size with X-ray 2-10 keV...

  10. The Lick AGN Monitoring Project: Recalibrating Single-Epoch Virial Black Hole Mass Estimates

    CERN Document Server

    Park, Daeseong; Treu, Tommaso; Barth, Aaron J; Bentz, Misty C; Bennert, Vardha N; Canalizo, Gabriela; Filippenko, Alexei V; Gates, Elinor; Greene, Jenny E; Malkan, Matthew A; Walsh, Jonelle

    2011-01-01

    We investigate the calibration and uncertainties of black hole mass estimates based on the single-epoch (SE) method, using homogeneous and high-quality multi-epoch spectra obtained by the Lick Active Galactic Nucleus (AGN) Monitoring Project for 9 local Seyfert 1 galaxies with black hole masses < 10^8 M_sun. By decomposing the spectra into their AGN and stellar components, we study the variability of the single-epoch Hbeta line width (full width at half-maximum intensity, FWHM_Hbeta; or dispersion, sigma_Hbeta) and of the AGN continuum luminosity at 5100A (L_5100). From the distribution of the "virial products" (~ FWHM_Hbeta^2 L_5100^0.5 or sigma_Hbeta^2 L_5100^0.5) measured from SE spectra, we estimate the uncertainty due to the combined variability as ~ 0.05 dex (12%). This is subdominant with respect to the total uncertainty in SE mass estimates, which is dominated by uncertainties in the size-luminosity relation and virial coefficient, and is estimated to be ~ 0.46 dex (factor of ~ 3). By comparing the...

  11. The Mass of the Black Hole in the X-ray Binary Nova Muscae 1991

    CERN Document Server

    Wu, Jianfeng; McClintock, Jeffrey E; Hasan, Imran; Bailyn, Charles D; Gou, Lijun; Chen, Zihan

    2016-01-01

    The optical counterpart of the black-hole soft X-ray transient Nova Muscae 1991 has brightened by $\\Delta{V}\\approx0.8$ mag since its return to quiescence 23 years ago. We present the first clear evidence that the brightening of soft X-ray transients in quiescence occurs at a nearly linear rate. This discovery, and our precise determination of the disk component of emission obtained using our $simultaneous$ photometric and spectroscopic data, have allowed us to identify and accurately model archival ellipsoidal light curves of the highest quality. The simultaneity, and the strong constraint it provides on the component of disk emission, is a key element of our work. Based on our analysis of the light curves, and our earlier measurements of the mass function and mass ratio, we have obtained for Nova Muscae 1991 the first accurate estimates of its systemic inclination $i=43.2^{+2.1}_{-2.7}$ deg, and black hole mass $M=11.0^{+2.1}_{-1.4}\\ M_\\odot$. Based on our determination of the radius of the secondary, we es...

  12. Neutron stars versus black holes: probing the mass gap with LIGO/Virgo

    CERN Document Server

    Littenberg, Tyson B; Coughlin, Scott; Kalogera, Vicky; Holz, Daniel E

    2015-01-01

    The inspirals and mergers of binary systems comprised of black holes (BHs) and/or neutron stars (NSs) are expected to be abundant sources for ground-based gravitational-wave (GW) detectors. We assess the capabilities of Advanced LIGO and Virgo to measure component masses using inspiral waveform models which include spin-precession effects by studying a large ensemble of plausible GW sources. We make quantitative predictions for how well LIGO and Virgo will be able to distinguish between black holes and neutron stars and appraise the prospect of using LIGO/Virgo observations to definitively confirm, or reject, the existence of a putative "mass gap" between NSs ($m\\leq3\\ M_\\odot$) and BHs ($m\\geq 5\\ M_\\odot$). We find sources with the smaller mass component satisfying $m_2 \\lesssim1.5\\ M_\\odot$ to be unambiguously identified as containing at least one NS, while systems with $m_2\\gtrsim6\\ M_\\odot$ will be confirmed binary BHs. However, binary BHs with $m_2<5\\ M_\\odot$ (i.e., in the gap) cannot be distinguishe...

  13. The Black-Hole Mass in M87 from Gemini/NIFS Adaptive Optics Observations

    CERN Document Server

    Gebhardt, Karl; Richstone, Douglas; Lauer, Tod R; Faber, S M; Gultekin, Kayhan; Murphy, Jeremy; Tremaine, Scott

    2011-01-01

    We present the stellar kinematics in the central 2" of the luminous elliptical galaxy M87 (NGC 4486), using laser adaptive optics to feed the Gemini telescope integral-field spectrograph, NIFS. The velocity dispersion rises to 480 km/s at 0.2". We combine these data with extensive stellar kinematics out to large radii to derive a black-hole mass equal to (6.6+-0.4)x10^9 Msun, using orbit-based axisymmetric models and including only the NIFS data in the central region. Including previously-reported ground-based data in the central region drops the uncertainty to 0.25x10^9 Msun with no change in the best-fit mass; however, we rely on the values derived from the NIFS-only data in the central region in order to limit systematic differences. The best-fit model shows a significant increase in the tangential velocity anisotropy of stars orbiting in the central region with decreasing radius; similar to that seen in the centers of other core galaxies. The black-hole mass is insensitive to the inclusion of a dark halo ...

  14. A Reverberation-Based Black Hole Mass for MCG-06-30-15

    CERN Document Server

    Bentz, Misty C; Crenshaw, D Michael; Horne, Keith; Street, Rachel; Ou-Yang, Benjamin

    2016-01-01

    We present the results of a reverberation campaign targeting MGC-06-30-15. Spectrophotometric monitoring and broad-band photometric monitoring over the course of 4 months in the spring of 2012 allowed a determination of a time delay in the broad H$\\beta$ emission line of $\\tau=5.3\\pm1.8$ days in the rest frame of the AGN. Combined with the width of the variable portion of the emission line, we determine a black hole mass of $M_{\\rm BH} = (1.6 \\pm 0.4) \\times 10^6$ M$_{\\odot}$. Both the H$\\beta$ time delay and the black hole mass are in good agreement with expectations from the $R_{\\rm BLR}$-$L$ and $M_{\\rm BH}-\\sigma_{\\star}$ relationships for other reverberation-mapped AGNs. The H$\\beta$ time delay is also in good agreement with the relationship between H$\\beta$ and broad-band near-IR delays, in which the effective BLR size is $\\sim 4-5$ times smaller than the inner edge of the dust torus. Additionally, the reverberation-based mass is in good agreement with estimates from the X-ray power spectral density bre...

  15. A Fast Method to Predict Distributions of Binary Black Hole Masses Based on Gaussian Process Regression

    Science.gov (United States)

    Yun, Yuqi; Zevin, Michael; Sampson, Laura; Kalogera, Vassiliki

    2017-01-01

    With more observations from LIGO in the upcoming years, we will be able to construct an observed mass distribution of black holes to compare with binary evolution simulations. This will allow us to investigate the physics of binary evolution such as the effects of common envelope efficiency and wind strength, or the properties of the population such as the initial mass function.However, binary evolution codes become computationally expensive when running large populations of binaries over a multi-dimensional grid of input parameters, and may simulate accurately only for a limited combination of input parameter values. Therefore we developed a fast machine-learning method that utilizes Gaussian Mixture Model (GMM) and Gaussian Process (GP) regression, which together can predict distributions over the entire parameter space based on a limited number of simulated models. Furthermore, Gaussian Process regression naturally provides interpolation errors in addition to interpolation means, which could provide a means of targeting the most uncertain regions of parameter space for running further simulations.We also present a case study on applying this new method to predicting chirp mass distributions for binary black hole systems (BBHs) in Milky-way like galaxies of different metallicities.

  16. Estimation of mass outflow rates from viscous relativistic accretion discs around black holes

    Science.gov (United States)

    Chattopadhyay, Indranil; Kumar, Rajiv

    2016-07-01

    We investigated flow in Schwarzschild metric, around a non-rotating black hole and obtained self-consistent accretion-ejection solution in full general relativity. We covered the whole of parameter space in the advective regime to obtain shocked, as well as, shock-free accretion solution. We computed the jet streamline using von Zeipel surfaces and projected the jet equations of motion on to the streamline and solved them simultaneously with the accretion disc equations of motion. We found that steady shock cannot exist beyond α ≳ 0.06 in the general relativistic prescription, but is lower if mass-loss is considered too. We showed that for fixed outer boundary, the shock moves closer to the horizon with increasing viscosity parameter. The mass outflow rate increases as the shock moves closer to the black hole, but eventually decreases, maximizing at some intermediate value of shock location. The jet terminal speed increases with stronger shocks; quantitatively speaking, the terminal speed of jets vj∞ > 0.1 if rsh < 20rg. The maximum of the outflow rate obtained in the general relativistic regime is less than 6 per cent of the mass accretion rate.

  17. A Reverberation-based Black Hole Mass for MCG-06-30-15

    Science.gov (United States)

    Bentz, Misty C.; Cackett, Edward M.; Crenshaw, D. Michael; Horne, Keith; Street, Rachel; Ou-Yang, Benjamin

    2016-10-01

    We present the results of a reverberation campaign targeting MGC-06-30-15. Spectrophotometric monitoring and broad-band photometric monitoring over the course of four months in spring 2012 allowed a determination of a time delay in the broad Hβ emission line of τ = 5.3 ± 1.8 days in the rest frame of the active galactic nucleus (AGN). Combined with the width of the variable portion of the emission line, we determine a black hole mass of M BH = (1.6 ± 0.4) × 106 M ⊙. Both the Hβ time delay and the black hole mass are in good agreement with expectations from the R BLR-L and M BH-σ ⋆ relationships for other reverberation-mapped AGNs. The Hβ time delay is also in good agreement with the relationship between Hβ and broad-band near-IR delays, in which the effective size of the broad-line region is ˜4-5 times smaller than the inner edge of the dust torus. Additionally, the reverberation-based mass is in good agreement with estimates from the scaling relationship of the break in the X-ray power spectral density, and with constraints based on stellar kinematics derived from integral field spectroscopy of the inner ˜0.5 kpc of the galaxy.

  18. Regulation of Black Hole Winds and Jets Across the Mass Scale

    CERN Document Server

    King, Ashley L; Raymond, John; Fabian, Andy C; Reynolds, Chris S; Gultekin, Kayhan; Cackett, Edward M; Allen, Steven W; Proga, Daniel; Kallman, Tim R

    2012-01-01

    We present a study of the mechanical power generated by both winds and jets across the black hole mass scale. We begin with the study of ionized X-ray winds and present a uniform analysis using Chandra grating spectra. The high quality grating spectra facilitate the characterization of the outflow velocity, ionization and column density of the absorbing gas. We find that the kinetic power of the winds scales with increasing bolometric luminosity as log(L_wind) \\propto (1.57 \\pm 0.07) log(L_Bol). This means that SMBH may be more efficient than stellar-mass black holes in launching winds. In addition, the simplicity of the scaling may suggest common driving mechanisms across the mass scale. For comparison, we next examine jet production, estimating jet power based on the energy required to inflate local bubbles. The jet relation is log(L_Jet)\\propto (1.18\\pm0.24) log(L_Bol). The energetics of the bubble associated with Cygnus X-1 are particularly difficult to determine, and the bubble could be a background SNR....

  19. Measuring intermediate mass black hole binaries with advanced gravitational wave detectors

    CERN Document Server

    Veitch, John; Mandel, Ilya

    2015-01-01

    We perform a systematic study to explore the accuracy with which the parameters of intermediate-mass black-hole binary systems can be measured from their gravitational wave (GW) signatures using second-generation GW detectors. We make use of the most recent reduced-order models containing inspiral, merger and ringdown signals of aligned-spin effective-one-body waveforms (SEOBNR) to significantly speed up the calculations. We explore the phenomenology of the measurement accuracies for binaries with total masses between 50 and 500 $M_\\odot$ and mass ratios between 0.1 and 1. We find that (i) at total masses below ~200 $M_\\odot$, where the signal-to-noise-ratio is dominated by the inspiral portion of the signal, the chirp mass parameter can be accurately measured; (ii) at higher masses, the information content is dominated by the ringdown, and total mass is measured more accurately; (iii) the mass of the lower-mass companion is poorly estimated, especially at high total mass and more extreme mass ratios; (iv) sp...

  20. A note on the black hole remnant

    OpenAIRE

    Xiang, Li

    2006-01-01

    Analyzing the tunneling probability of a Schwarzschild black hole with a negative log-area correction to Bekenstein-Hawking entropy, I argue that this correction may be closely related to a black hole remnant. The value for the minimal black hole mass is also discussed.

  1. On Quantum Contributions to Black Hole Growth

    NARCIS (Netherlands)

    Spaans, M.

    2013-01-01

    The effects of Wheeler’s quantum foam on black hole growth are explored from an astrophysical per- spective. Quantum fluctuations in the form of mini (10−5 g) black holes can couple to macroscopic black holes and allow the latter to grow exponentially in mass on a time scale of 109 years. Consequent

  2. Charged Black Holes in New Massive Gravity

    OpenAIRE

    Ghodsi, Ahmad; Moghadassi, Mohammad

    2010-01-01

    We construct charged black hole solutions to three-dimensional New Massive Gravity (NMG), by adding electromagnetic Maxwell and Chern-Simons actions. We find charged black holes in the form of warped AdS_3 and "log" solutions in specific critical point. The entropy, mass and angular momentum of these black holes are computed.

  3. Formation of Supermassive Black Holes

    CERN Document Server

    Volonteri, Marta

    2010-01-01

    Evidence shows that massive black holes reside in most local galaxies. Studies have also established a number of relations between the MBH mass and properties of the host galaxy such as bulge mass and velocity dispersion. These results suggest that central MBHs, while much less massive than the host (~ 0.1%), are linked to the evolution of galactic structure. In hierarchical cosmologies, a single big galaxy today can be traced back to the stage when it was split up in hundreds of smaller components. Did MBH seeds form with the same efficiency in small proto-galaxies, or did their formation had to await the buildup of substantial galaxies with deeper potential wells? I briefly review here some of the physical processes that are conducive to the evolution of the massive black hole population. I will discuss black hole formation processes for `seed' black holes that are likely to place at early cosmic epochs, and possible observational tests of these scenarios.

  4. Space, time, and black holes

    Energy Technology Data Exchange (ETDEWEB)

    Darling, D.

    1980-10-01

    A discussion of Einstein's General Relativity and how it can explain black holes is included. The key idea of general relativity being that gravitational forces are a direct outcome of local curvature of space-time. The more mass something has the deeper the depression or well it causes in space-time. Black holes are supermassive objects, hence their gravity well is so steep even light can't escape. The three properties associated with a black hole are mass angular momentum, and electric charge. Non-rotating, Schwarzchild, and rotating, Kerr, black holes are studied. A Kruskal-Szekeres diagram for each type is given and explained. (SC)

  5. Magnetic fields around black holes

    Science.gov (United States)

    Garofalo, David A. G.

    Active Galactic Nuclei are the most powerful long-lived objects in the universe. They are thought to harbor supermassive black holes that range from 1 million solar masses to 1000 times that value and possibly greater. Theory and observation are converging on a model for these objects that involves the conversion of gravitational potential energy of accreting gas to radiation as well as Poynting flux produced by the interaction of the rotating spacetime and the electromagnetic fields originating in the ionized accretion flow. The presence of black holes in astrophysics is taking center stage, with the output from AGN in various forms such as winds and jets influencing the formation and evolution of the host galaxy. This dissertation addresses some of the basic unanswered questions that plague our current understanding of how rotating black holes interact with their surrounding magnetized accretion disks to produce the enormous observed energy. Two magnetic configurations are examined. The first involves magnetic fields connecting the black hole with the inner accretion disk and the other involves large scale magnetic fields threading the disk and the hole. We study the effects of the former type by establishing the consequences that magnetic torques between the black hole and the inner accretion disk have on the energy dissipation profile. We attempt a plausible explanation to the observed "Deep Minimum" state in the Seyfert galaxy MCG-6- 30-15. For the latter type of magnetic geometry, we study the effects of the strength of the magnetic field threading the black hole within the context of the cherished Blandford & Znajek mechanism for black hole spin energy extraction. We begin by addressing the problem in the non-relativistic regime where we find that the black hole-threading magnetic field is stronger for greater disk thickness, larger magnetic Prandtl number, and for a larger accretion disk. We then study the problem in full relativity where we show that our

  6. Mass and angular momentum of black holes in low-energy heterotic string theory

    Science.gov (United States)

    Peng, Jun-Jin

    2016-04-01

    We investigate conserved charges in the low-energy effective field theory describing heterotic string theory. Starting with a general Lagrangian that consists of a metric, a scalar field, a vector gauge field, together with a two-form potential, we derive off-shell Noether potentials of the Lagrangian and generalize the Abbott-Deser-Tekin (ADT) formalism to the off-shell level by establishing one-to-one correspondence between the ADT potential and the off-shell Noether potential. It is proved that the off-shell generalized ADT formalism is conformally invariant. Then, we apply the formulation to compute mass and angular momentum of the four-dimensional Kerr-Sen black hole and the five-dimensional rotating charged black string in the string frame without a necessity to transform the metrics into the Einstein frame.

  7. Mass and angular momentum of black holes in low-energy heterotic string theory

    CERN Document Server

    Peng, Jun-Jin

    2016-01-01

    We investigate conserved charges in the low-energy effective field theory describing heterotic string theory. Starting with a general Lagrangian that consists of a metric, a scalar field, a vector gauge field, together with a two-form potential, we derive off-shell Noether potentials of the Lagrangian and generalize the Abbott-Deser-Tekin (ADT) formalism to the off-shell level by establishing one-to-one correspondence between the ADT potential and the off-shell Noether potential. It is proved that the off-shell generalized ADT formalism is conformally invariant. Then we apply the formulation to compute mass and angular momentum of the four-dimensional Kerr-Sen black hole and the five-dimensional rotating charged black string in the string frame without a necessity to transform the metrics into the Einstein frame.

  8. Megamaser Disks Reveal a Broad Distribution of Black Hole Mass in Spiral Galaxies

    Science.gov (United States)

    Greene, J. E.; Seth, A.; Kim, M.; Läsker, R.; Goulding, A.; Gao, F.; Braatz, J. A.; Henkel, C.; Condon, J.; Lo, K. Y.; Zhao, W.

    2016-08-01

    We use new precision measurements of black hole (BH) masses from water megamaser disks to investigate scaling relations between macroscopic galaxy properties and supermassive BH mass. The megamaser-derived BH masses span 106-108 {M}⊙ , while all the galaxy properties that we examine (including total stellar mass, central mass density, and central velocity dispersion) lie within a narrower range. Thus, no galaxy property correlates tightly with {M}{BH} in ˜L* spiral galaxies as traced by megamaser disks. Of them all, stellar velocity dispersion provides the tightest relation, but at fixed {σ }* the mean megamaser {M}{BH} are offset by -0.6 ± 0.1 dex relative to early-type galaxies. Spiral galaxies with non-maser dynamical BH masses do not appear to show this offset. At low mass, we do not yet know the full distribution of BH mass at fixed galaxy property; the non-maser dynamical measurements may miss the low-mass end of the BH distribution due to an inability to resolve their spheres of influence and/or megamasers may preferentially occur in lower-mass BHs.

  9. Mass Gap for Black-Hole Formation in Higher-Derivative and Ghost-Free Gravity

    Science.gov (United States)

    Frolov, Valeri P.

    2015-07-01

    We study a spherical gravitational collapse of a small mass in higher-derivative and ghost-free theories of gravity. By boosting a solution of linearized equations for a static point mass in such theories we obtain in the Penrose limit the gravitational field of an ultrarelativistic particle. Taking a superposition of such solutions we construct a metric of a collapsing null shell in the linearized higher-derivative and ghost-free gravity. The latter allows one to find the gravitational field of a thick null shell. By analyzing these solutions we demonstrate that in a wide class of the higher dimensional theories of gravity as well as for the ghost-free gravity there exists a mass gap for mini-black-hole production. We also found conditions when the curvature invariants remain finite at r =0 for the collapse of the thick null shell.

  10. Mass-gap for black hole formation in higher derivative and ghost free gravity

    CERN Document Server

    Frolov, Valeri P

    2015-01-01

    We study a spherical gravitational collapse of a small mass in higher derivative and ghost free theories of gravity. By boosting a solution of linearized equations for a static point mass in such theories we obtain in the Penrose limit the gravitational field of an ultra-relativistic particle. Taking a superposition of such solutions we construct a metric of a collapsing null shell in the linearized higher derivative and ghost free gravity. The latter allows one to find the gravitational field of a thick null shell. By analysing these solutions we demonstrate that in a wide class of the higher dimensional theories of gravity as well as for the ghost free gravity there exists a mass gap for the mini black hole production. We also found conditions when the curvature invariants remain finite at $r=0$ for the collapse of the thick null shell.

  11. The correlation of black hole mass with metallicity index of host spheroid

    CERN Document Server

    Kisaka, Shota; Otani, Yosuke

    2008-01-01

    We investigate the correlation between the mass of the supermassive black holes (SMBHs) and metal abundance, using existing data sets. The SMBH mass $M_{bh}$ is well correlated with integrated stellar feature of Mgb. For 28 galaxies, the best-fit $M_{bh}$-Mgb relation has a small scatter, which is an equivalent level with other well-known relation, such as a correlation between the stellar velocity dispersion and the mass. An averaged iron index $$ also positively correlates with $M_{bh}$, but the best-fit $M_{bh}$-$$ relation has a larger scatter. The difference comes from the synthesis and evolution mechanisms, and may be important for the SMBH and star formation history in the host spheroid.

  12. A Polarimetric Method for Measuring Black Hole Masses in Active Galactic Nuclei

    CERN Document Server

    Piotrovich, M Yu; Silant'ev, N A; Natsvlishvili, T M; Buliga, S D

    2015-01-01

    The structure of the broad emission line region (BLR) in active galactic nuclei (AGN) remains unclear. We test in this paper a flattened configuration model for BLR. The virial theorem, by taking into account the disc shape of BLR, allows us to get a direct connection between the mass of a supermassive black hole (SMBH) and the inclination angle of the accretion flow. The inclination angle itself is derived from the spectropolarimetric data on broad emission lines using the theory for the generation of polarized radiation developed by Sobolev and Chandrasekhar. As the result, the new estimates of SMBH masses in AGN with measured polarization of BLR are presented. It is crucial that the polarimetric data allow also to determine the value of the virial coefficient that is essential for determining SMBH masses.

  13. Geometric inequalities for black holes

    CERN Document Server

    Dain, Sergio

    2014-01-01

    It is well known that the three parameters that characterize the Kerr black hole (mass, angular momentum and horizon area) satisfy several important inequalities. Remarkably, some of these inequalities remain valid also for dynamical black holes. This kind of inequalities play an important role in the characterization of the gravitational collapse. They are closed related with the cosmic censorship conjecture. In this article recent results in this subject are reviewed.

  14. Mergers of neutron star black hole binaries with small mass ratios: nucleosynthesis, gamma-ray bursts and electromagnetic transients

    CERN Document Server

    Rosswog, S

    2005-01-01

    I discuss simulations of the coalescence of black hole neutron star binary systems with black hole masses between 14 and 20 \\msun. The calculations use a three-dimensional smoothed particle hydrodynamics code, a temperature-dependent, nuclear equation of state and a multi-flavor neutrino scheme. General relativistic effects are mimicked using the \\Pacz-Wiita pseudo-potential and gravitational radiation reaction forces. Opposite to previous, purely Newtonian calculations, in none of the explored cases episodic mass transfer occurs. The neutron star is always completely disrupted after most of its mass has been transferred directly into the hole. For black hole masses between 14 and 16 \\Msun an accretion disk forms, large parts of it, however, are inside the last stable orbit and therefore falling with large radial velocities into the hole. These disks are (opposite to the neutron star merger case) thin and -apart from a spiral shock- essentially cold. For higher mass black holes ($M_{\\rm BH} \\ge 18$ \\msun) alm...

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

    CERN Document Server

    Hopman, C; Alexander, Tal; Hopman, Clovis

    2006-01-01

    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.

  16. New Estimators of Black Hole Mass in Active Galactic Nuclei with Hydrogen Paschen Lines

    CERN Document Server

    Kim, Dohyeong; Kim, Minjin; 10.1088/0004-637X/724/1/386

    2010-01-01

    More than 50% of Active Galactic Nuclei (AGNs) are suspected to be red and affected by dust-obscuration. Meanwhile, popular spectral diagnostics of AGNs are based on optical or ultraviolet light, making the dust obscuration as a primary concern for understanding the general nature of AGNs and supermassive black holes residing in them. To provide with a method of investigating properties of the dusty AGNs, we derive new black hole (BH) mass estimators based on velocity widths and luminosities of Near Infrared (NIR) hydrogen emission lines such as P$\\alpha$ and P$\\beta$, and also investigate the line ratios of these Hydrogen lines. To derive the BH mass ($M_{\\rm BH}$) estimators, we used a sample of 37 unobscured Type-1 AGNs with a $M_{\\rm BH}$ range of $10^{6.8}$-$10^{9.4} M_{\\odot}$, where $M_{\\rm BH}$ come from either reverberation mapping method or single-epoch measurement method using Balmer lines. Our work shows that $M_{\\rm BH}$ can be estimated from the Paschen line luminosities and the velocity widths ...

  17. Revisiting the Scaling Relations of Black Hole Masses and Host Galaxy Properties

    CERN Document Server

    McConnell, Nicholas J

    2012-01-01

    New kinematic data and modeling efforts in the past few years have substantially expanded and revised dynamical measurements of black hole masses (Mbh) at the centers of nearby galaxies. Here we compile an updated sample of 72 black holes and their host galaxies, and present revised scaling relations between Mbh and stellar velocity dispersion (sigma), V-band luminosity (L), and bulge stellar mass (Mbulge), for different galaxy subsamples. Our best-fitting power law relations for the full galaxy sample are log(Mbh) = 8.33 + 5.57*log(sigma/200 kms), log(Mbh) = 9.23 + 1.11*log(L/10^{11} Lsun), and log(Mbh) = 8.46 + 1.05*log(Mbulge/10^{11} Msun). When the early- and late-type galaxies are fit separately, we obtain nearly identical slopes of ~5 for the Mbh-sigma relation but significantly different intercepts. Within early-type galaxies, we find a significantly higher intercept for galaxies with central core profiles than for those with central power-law profiles. At fixed sigma, our fits predict Mbh to be about ...

  18. Do Circumnuclear Dense Gas Disks Drive Mass Accretion onto Supermassive Black Holes?

    CERN Document Server

    Izumi, Takuma; Kohno, Kotaro

    2016-01-01

    We present a positive correlation between the mass of dense molecular gas ($M_{\\rm dense}$) of $\\sim 100$ pc scale circumnuclear disks (CNDs) and the black hole mass accretion rate ($\\dot{M}_{\\rm BH}$) in total 10 Seyfert galaxies, based on data compiled from the literature and an archive (median aperture $\\theta_{\\rm med}$ = 220 pc). A typical $M_{\\rm dense}$ of CNDs is 10$^{7-8}$ $M_\\odot$, estimated from the luminosity of the dense gas tracer, the HCN($1-0$) emission line. Because dense molecular gas is the site of star formation, this correlation is virtually equivalent to the one between nuclear star formation rate and $\\dot{M}_{\\rm BH}$ revealed previously. Moreover, the $M_{\\rm dense}-\\dot{M}_{\\rm BH}$ correlation was tighter for CND-scale gas than for the gas on kpc or larger scales. This indicates that CNDs likely play an important role in fueling black holes, whereas $>$kpc scale gas does not. To demonstrate a possible approach for studying the CND-scale accretion process with the Atacama Large Mill...

  19. Assisted inspirals of stellar mass black holes embedded in AGN discs: solving the `final au problem'

    Science.gov (United States)

    Stone, Nicholas C.; Metzger, Brian D.; Haiman, Zoltán

    2017-01-01

    We explore the evolution of stellar mass black hole binaries (BHBs) which are formed in the self-gravitating discs of active galactic nuclei (AGN). Hardening due to three-body scattering and gaseous drag are effective mechanisms that reduce the semimajor axis of a BHB to radii where gravitational waves take over, on time-scales shorter than the typical lifetime of the AGN disc. Taking observationally motivated assumptions for the rate of star formation in AGN discs, we find a rate of disc-induced BHB mergers (R ˜ 3 yr^{-1} Gpc^{-3}, but with large uncertainties) that is comparable with existing estimates of the field rate of BHB mergers, and the approximate BHB merger rate implied by the recent Advanced LIGO detection of GW150914. BHBs formed thorough this channel will frequently be associated with luminous AGN, which are relatively rare within the sky error regions of future gravitational wave detector arrays. This channel could also possess a (potentially transient) electromagnetic counterpart due to super-Eddington accretion on to the stellar mass black hole following the merger.

  20. Assisted Inspirals of Stellar Mass Black Holes Embedded in AGN Disks: Solving the "Final AU Problem"

    Science.gov (United States)

    Stone, Nicholas C.; Metzger, Brian D.; Haiman, Zoltán

    2016-09-01

    We explore the evolution of stellar mass black hole binaries (BHBs) which are formed in the self-gravitating disks of active galactic nuclei (AGN). Hardening due to three-body scattering and gaseous drag are effective mechanisms that reduce the semi-major axis of a BHB to radii where gravitational waves take over, on timescales shorter than the typical lifetime of the AGN disk. Taking observationally-motivated assumptions for the rate of star formation in AGN disks, we find a rate of disk-induced BHB mergers (R ˜ 3 yr^{-1} Gpc^{-3}, but with large uncertainties) that is comparable with existing estimates of the field rate of BHB mergers, and the approximate BHB merger rate implied by the recent Advanced LIGO detection of GW150914. BHBs formed thorough this channel will frequently be associated with luminous AGN, which are relatively rare within the sky error regions of future gravitational wave detector arrays. This channel could also possess a (potentially transient) electromagnetic counterpart due to super-Eddington accretion onto the stellar mass black hole following the merger.

  1. Short Timescale AGN X-ray Variability with EXOSAT: Black hole mass and Normalised Variability Amplitude

    CERN Document Server

    McHardy, I M

    2012-01-01

    The old EXOSAT medium energy measurements of high frequency (HF) AGN power spectral normalisation are re-examined in the light of accurate black hole mass determinations which were not available when these data were first published (Green et al 1993). It is found that the normalised variability amplitude (NVA), measured directly from the power spectrum, is proportional to M^{beta} where beta ~ -0.54 +/- 0.08. As NVA is the square root of the power, these observations show that the normalisation of the HF power spectrum for this sample of AGN varies very close to inversely with black hole mass. Almost the same value of $\\beta$ is obtained whether the quasar 3C273 is included in the sample or not, suggesting that the same process that drives X-ray variability in Seyfert galaxies applies also to 3C273. These observations support the work of Gierlinski et al (2008) who show that an almost exactly linear anticorrelation is required if the normalisations of the HF power spectra of AGN and X-ray binary systems are t...

  2. The mass density in black holes inferred from the X-ray background

    CERN Document Server

    Fabian, A C

    1999-01-01

    The X-ray Background (XRB) probably originates from the integrated X-ray emission of active galactic nuclei (AGN). Modelling of its flat spectrum implies considerable absorption in most AGN. Compton down-scattering means that sources in which the absorption is Compton thick are unlikely to be major contributors to the background intensity so the observed spectral intensity at about 30 keV is little affected by photoelectric absorption. Assuming that the intrinsic photon index of AGN is 2, we then use the 30 keV intensity of the XRB to infer the absorption-corrected energy density of the background. Soltan's argument then enables us to convert this to a mean local density in black holes, assuming an accretion efficiency of 0.1 and a mean AGN redshift of 2. The result is within a factor of two of that estimated by Haehnelt et al from the optically-determined black hole masses of Magorrian et al. We conclude that there is no strong need for any radiatively inefficient mode of accretion for building the masses of...

  3. Ejection of Hyper-Velocity Stars from the Galactic Centre by Intermediate-Mass Black Holes

    CERN Document Server

    Baumgardt, H; Zwart, S P; Baumgardt, Holger; Gualandris, Alessia; Zwart, Simon Portegies

    2006-01-01

    We have performed N-body simulations of the formation of hyper-velocity stars (HVS) in the centre of the Milky Way due to inspiralling intermediate-mass black holes (IMBHs). We considered IMBHs of different masses, all starting from circular orbits at an initial distance of 0.1 pc. We find that the IMBHs sink to the centre of the Galaxy due to dynamical friction, where they deplete the central cusp of stars. Some of these stars become HVS and are ejected with velocities sufficiently high to escape the Galaxy. Since the HVS carry with them information about their origin, in particular in the moment of ejection, the velocity distribution and the direction in which they escape the Galaxy, detecting a population of HVS will provide insight in the ejection processes and could therefore provide indirect evidence for the existence of IMBHs. Our simulations show that HVS are generated in short bursts which last only a few Myrs until the IMBH is swallowed by the supermassive black hole (SMBH). HVS are ejected almost i...

  4. A Method for Black Hole Mass Determination in Accretion Powered X-Ray Sources

    CERN Document Server

    Shrader, C R; Shrader, Chris; Titarchuk, Lev

    2003-01-01

    We describe a method for the determination of black-hole masses based on information inferred from high-energy spectra. It is required that the spectral energy distribution consist of thermal and Comptonized components. One can then, in principle, infer the depth of the gravitational potential well for sources of known distance. The thermal component is inferred by the integration of a blackbody spectral form over the disk. We assume that the color temperature distribution in the disk has a specific shape given by the Shakura-Sunyaev (1973) disk model which goes to zero at the inner disk radius and at infinity and has a maximum at 4.2 Schwarzchild radii. In this formulation there is only one parameter, the so called color correction factor, relating the apparent temperature to effective temperature which characterizes the thermal emission component. We have made use of improved Galactic black hole binary dynamical mass determinations to derive, in effect, an empirical calibration of this factor. We then prese...

  5. The Galactic Centre star S2 as a dynamical probe for intermediate-mass black holes

    CERN Document Server

    Gualandris, Alessia; Merritt, David

    2010-01-01

    We study the short-term effects of an intermediate mass black hole (IBH) on the orbit of star S2 (S02), the shortest period star known to orbit the supermassive black hole (SBH) in the centre of the Milky Way. Near-infrared imaging and spectroscopic observations allow an accurate determination of the orbit of the star. Given S2's short orbital period and large eccentricity, general relativity (GR) needs to be taken into account, and its effects are potentially measurable with current technology. We show that perturbations due to an IBH in orbit around the SBH can produce a shift in the apoapsis of S2 that is as large or even larger than the GR shift. An IBH will also induce changes in the plane of S2's orbit at a level as large as one degree per period. We apply observational orbital fitting techniques to simulations of the S-cluster in the presence of an IBH and find that an IBH more massive than about 1000 solar masses at the distance of the S-stars will be detectable at the next periapse passage of S2, whi...

  6. Detecting intermediate mass black holes in globular clusters with machine learning.

    Science.gov (United States)

    Pasquato, M.

    Mergers of stellar-mass black holes were recently observed in the gravitational wave window opened by LIGO. This puts the spotlight on dense stellar systems and their ability to create intermediate-mass black holes (IMBHs) through repeated merging. Unfortunately, attempts at direct and indirect IMBH detection in star clusters in the nearby universe have proven inconclusive as of now. Indirect detection methods attempt to constrain IMBHs through their effect on star cluster photometric and kinematic observables. They are usually based on looking for a specific, physically motivated signature. While this approach is justified, it may be suboptimal in its usage of the available data. Here I present a new indirect detection method, based on machine learning, that is unaffected by these restrictions. I reduce the scientific question whether a star cluster hosts an IMBH to a classification problem in the machine learning framework. I present preliminary results to illustrate how machine learning models are trained on simulated dataset and measure their performance on previously unseen, simulated data.

  7. Rotating black hole and quintessence

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Sushant G. [Jamia Millia Islamia, Centre for Theoretical Physics, New Delhi (India); University of KwaZulu-Natal, Astrophysics and Cosmology Research Unit, School of Mathematics, Statistics and Computer Science, Private Bag 54001, Durban (South Africa)

    2016-04-15

    We discuss spherically symmetric exact solutions of the Einstein equations for quintessential matter surrounding a black hole, which has an additional parameter (ω) due to the quintessential matter, apart from the mass (M). In turn, we employ the Newman-Janis complex transformation to this spherical quintessence black hole solution and present a rotating counterpart that is identified, for α = -e{sup 2} ≠ 0 and ω = 1/3, exactly as the Kerr-Newman black hole, and as the Kerr black hole when α = 0. Interestingly, for a given value of parameter ω, there exists a critical rotation parameter (a = a{sub E}), which corresponds to an extremal black hole with degenerate horizons, while for a < a{sub E}, it describes a nonextremal black hole with Cauchy and event horizons, and no black hole for a > a{sub E}. We find that the extremal value a{sub E} is also influenced by the parameter ω and so is the ergoregion. (orig.)

  8. A search of new samples of active galactic nuclei with low-mass black holes from SDSS

    Science.gov (United States)

    Liu, H.; Yuan, W.; Zhou, H.; Dong, X.-B.

    2016-02-01

    We report on the progress of our on-going work to search for low-mass black holes (LMBHs) in active galactic nuclei. The masses of black holes are estimated using the broad line width and luminosity obtained from one-epoch optical spectra. As the first step, we fitted the spectra of 1263 objects in the quasar catalog of the SDSS DR10 and obtained accurate measurement of the emission lines. Two AGNs are found to have M BH ~ 106 M⊙. The next step is to analyze the spectra of the DR10 galaxy sample, from which a much larger sample of low-mass AGNs is expected to be obtained.

  9. Dyonic Non-Abelian Black Holes

    CERN Document Server

    Brihaye, Y; Kunz, J; Tell, N

    1999-01-01

    We study static spherically symmetric dyonic black holes in Einstein-Yang-Mills-Higgs theory. As for the magnetic non-abelian black holes, the domain of existence of the dyonic non-abelian black holes is limited with respect to the horizon radius and the dimensionless coupling constant $\\alpha$, which is proportional to the ratio of vector meson mass and Planck mass. At a certain critical value of this coupling constant, $\\hat \\alpha$, the maximal horizon radius is attained. We derive analytically a relation between $\\hat numerically. Besides the fundamental dyonic non-abelian black holes, we study radially excited dyonic non-abelian black holes and globally regular gravitating dyons.

  10. Perturbing supersymmetric black hole

    CERN Document Server

    Onozawa, H; Mishima, T; Ishihara, H; Onozawa, Hisashi; Okamura, Takashi; Mishima, Takashi; Ishihara, Hideki

    1996-01-01

    An investigation of the perturbations of the Reissner-Nordstr\\"{o}m black hole in the N=2 supergravity is presented. In the extreme case, the black hole responds to the perturbation of each field in the same manner. This is possibly because we can match the modes of the graviton, gravitino, and photon using supersymmetry transformations.

  11. Black Hole Dynamic Potentials

    Indian Academy of Sciences (India)

    Koustubh Ajit Kabe

    2012-09-01

    In the following paper, certain black hole dynamic potentials have been developed definitively on the lines of classical thermodynamics. These potentials have been refined in view of the small differences in the equations of the laws of black hole dynamics as given by Bekenstein and those of thermodynamics. Nine fundamental black hole dynamical relations have been developed akin to the four fundamental thermodynamic relations of Maxwell. The specific heats , and , have been defined. For a black hole, these quantities are negative. The d equation has been obtained as an application of these fundamental relations. Time reversible processes observing constancy of surface gravity are considered and an equation connecting the internal energy of the black hole , the additional available energy defined as the first free energy function , and the surface gravity , has been obtained. Finally as a further application of the fundamental relations, it has been proved for a homogeneous gravitational field in black hole space times or a de Sitter black hole that $C_{\\Omega,\\Phi}-C_{J,Q}=\\kappa \\left[\\left(\\dfrac{\\partial J}{\\partial \\kappa}\\right)_{\\Omega,\\Phi}\\left(\\dfrac{\\partial \\Omega}{\\partial \\kappa}\\right)_{J,Q}+\\left(\\dfrac{\\partial Q}{\\partial \\kappa}\\right)_{\\Omega,\\Phi}\\left(\\dfrac{\\partial\\Phi}{\\partial \\kappa}\\right)_{J,Q}\\right]$. This is dubbed as the homogeneous fluid approximation in context of the black holes.

  12. Black holes matter

    DEFF Research Database (Denmark)

    Kragh, Helge Stjernholm

    2016-01-01

    Review essay, Marcia Bartusiak, Black Hole: How an Idea Abandoned by Newtonians, Hated by Einstein, and Gambled On by Hawking Became Loved (New Haven: Yale University Press, 2015).......Review essay, Marcia Bartusiak, Black Hole: How an Idea Abandoned by Newtonians, Hated by Einstein, and Gambled On by Hawking Became Loved (New Haven: Yale University Press, 2015)....

  13. Scattering by Black Holes

    CERN Document Server

    Andersson, N

    2000-01-01

    This is a chapter on Black-hole Scattering that was commissioned for an Encyclopaedia on Scattering edited by Pike and Sabatier, to be published by Academic Press. The chapter surveys wave propagation in black-hole spacetimes, diffraction effects in wave scattering, resonances, quasinormal modes and related topics.

  14. The Black Hole Universe Model

    Science.gov (United States)

    Zhang, Tianxi

    2014-06-01

    The black hole universe model is a multiverse model of cosmology recently developed by the speaker. According to this new model, our universe is a fully grown extremely supermassive black hole, which originated from a hot star-like black hole with several solar masses, and gradually grew up from a supermassive black hole with million to billion solar masses to the present state with trillion-trillion solar masses by accreting ambient matter or merging with other black holes. The entire space is structured with infinite layers or universes hierarchically. The innermost three layers include the universe that we live, the inside star-like and supermassive black holes called child universes, and the outside space called mother universe. The outermost layer is infinite in mass, radius, and entropy without an edge and limits to zero for both the matter density and absolute temperature. All layers are governed by the same physics and tend to expand physically in one direction (outward or the direction of increasing entropy). The expansion of a black hole universe decreases its density and temperature but does not alter the laws of physics. The black hole universe evolves iteratively and endlessly without a beginning. When one universe expands out, a new similar one is formed from inside star-like and supermassive black holes. In each of iterations, elements are resynthesized, matter is reconfigurated, and the universe is renewed rather than a simple repeat. The black hole universe is consistent with the Mach principle, observations, and Einsteinian general relativity. It has only one postulate but is able to explain all phenomena occurred in the universe with well-developed physics. The black hole universe does not need dark energy for acceleration and an inflation epoch for flatness, and thus has a devastating impact on the big bang model. In this talk, I will present how this new cosmological model explains the various aspects of the universe, including the origin

  15. A STACKED SEARCH FOR INTERMEDIATE-MASS BLACK HOLES IN 337 EXTRAGALACTIC STAR CLUSTERS

    Energy Technology Data Exchange (ETDEWEB)

    Wrobel, J. M. [National Radio Astronomy Observatory, P.O. Box O, Socorro, NM 87801 (United States); Nyland, K. E. [Netherlands Institute for Radio Astronomy, Postbus 2, 7990 AA, Dwingeloo (Netherlands); Miller-Jones, J. C. A., E-mail: jwrobel@nrao.edu, E-mail: nyland@astron.nl, E-mail: james.miller-jones@curtin.edu.au [International Centre for Radio Astronomy Research, Curtin University, GPO Box U1987, Perth, WA 6845 (Australia)

    2015-10-15

    Forbes et al. recently used the Hubble Space Telescope to localize hundreds of candidate star clusters in NGC 1023, an early-type galaxy at a distance of 11.1 Mpc. Old stars dominate the light of 92% of the clusters and intermediate-age stars dominate the light of the remaining 8%. Theory predicts that clusters with such ages can host intermediate-mass black holes (IMBHs) with masses To investigate this prediction, we used 264 s of 5.5 GHz data from the Karl G. Jansky Very Large Array to search for the radiative signatures of IMBH accretion from 337 candidate clusters in an image spanning 492″ (26 kpc) with a resolution of 0.″40 (22 pc). None of the individual clusters are detected, nor are weighted-mean image stacks of the 311 old clusters, the 26 intermediate-age clusters, and the 20 clusters with stellar masses The clusters thus lack radio analogs of HLX-1, a strong IMBH candidate in a cluster in the early-type galaxy ESO 243-49. This suggests that HLX-1 is accreting gas related to its cluster's light-dominating young stars. Alternatively, the HLX-1 phenomenon could be so rare that no radio analog is expected in NGC 1023. Also, using a formalism heretofore applied to star clusters in the Milky Way, the radio-luminosity upper limit for the massive-cluster stack corresponds to a 3σ IMBH mass of suggesting black hole mass fractions of.

  16. Cosmological Black Holes

    CERN Document Server

    Stornaiolo, C

    2002-01-01

    In this letter we propose the existence of low density black holes and discuss its compatibility with the cosmological observations. The origin of these black holes can be traced back to the collapse of long wavelength cosmological perturbations during the matter dominated era, when the densities are low enough to neglect any internal and thermal pressure. By introducing a threshold density $\\hat{\\rho}$ above which pressure and non-gravitational interactions become effective, we find the highest wavelength for the perturbations that can reach an equilibrium state instead of collapsing to a black hole. The low density black holes introduced here, if they exist, can be observed through weak and strong gravitational lensing effects. Finally we observe that we obtained here a cosmological model which is capable to explain in a qualitative way the void formation together with the value $\\Omega=1$. But we remark that it needs to be improved by considering non spherical symmetric black holes.

  17. Lifshitz Topological Black Holes

    CERN Document Server

    Mann, R B

    2009-01-01

    I find a class of black hole solutions to a (3+1) dimensional theory gravity coupled to abelian gauge fields with negative cosmological constant that has been proposed as the dual theory to a Lifshitz theory describing critical phenomena in (2+1) dimensions. These black holes are all asymptotic to a Lifshitz fixed point geometry and depend on a single parameter that determines both their area (or size) and their charge. Most of the solutions are obtained numerically, but an exact solution is also obtained for a particular value of this parameter. The thermodynamic behaviour of large black holes is almost the same regardless of genus, but differs considerably for small black holes. Screening behaviour is exhibited in the dual theory for any genus, but the critical length at which it sets in is genus-dependent for small black holes.

  18. Black Hole Thermodynamics

    CERN Document Server

    Carlip, S

    2014-01-01

    The discovery in the early 1970s that black holes radiate as black bodies has radically affected our understanding of general relativity, and offered us some early hints about the nature of quantum gravity. In this chapter I will review the discovery of black hole thermodynamics and summarize the many independent ways of obtaining the thermodynamic and (perhaps) statistical mechanical properties of black holes. I will then describe some of the remaining puzzles, including the nature of the quantum microstates, the problem of universality, and the information loss paradox.

  19. The Missing Link: Bayesian Detection and Measurement of Intermediate-Mass Black-Hole Binaries

    CERN Document Server

    Graff, Philip B; Sathyaprakash, B S

    2015-01-01

    We perform Bayesian analysis of gravitational-wave signals from non-spinning, intermediate-mass black-hole binaries (IMBHBs) with observed total mass, $M_{\\mathrm{obs}}$, from $50\\mathrm{M}_{\\odot}$ to $500\\mathrm{M}_{\\odot}$ and mass ratio $1\\mbox{--}4$ using advanced LIGO and Virgo detectors. We employ inspiral-merger-ringdown waveform models based on the effective-one-body formalism and include subleading modes of radiation beyond the leading $(2,2)$ mode. The presence of subleading modes increases signal power for inclined binaries and allows for improved accuracy and precision in measurements of the masses as well as breaking of extrinsic parameter degeneracies. For low total masses, $M_{\\mathrm{obs}} \\lesssim 50 \\mathrm{M}_{\\odot}$, the observed chirp mass $\\mathcal{M}_{\\rm obs} = M_{\\mathrm{obs}}\\,\\eta^{3/5}$ ($\\eta$ being the symmetric mass ratio) is better measured. In contrast, as increasing power comes from merger and ringdown, we find that the total mass $M_{\\mathrm{obs}}$ has better relative prec...

  20. Estimating the fossil disc mass during supermassive black hole mergers: the importance of torque implementation

    CERN Document Server

    Tazzari, Marco

    2015-01-01

    In this paper, we revisit the issue of estimating the "fossil" disc mass in the circumprimary disc, during the merger of a supermassive black hole binary. As the binary orbital decay speeds up due to the emission of gravitational waves, the gas in the circumprimary disc might be forced to accrete rapidly and could in principle provide a significant electromagnetic counterpart to the gravitational wave emission. Since the luminosity of such flare is proportional to the gaseous mass in the circumprimary disc, estimating such mass accurately is important. Previous investigations of this issue have produced contradictory results, with some authors estimating super-Eddington flares and large disc mass, while others suggesting that the "fossil" disc mass is very low, even less than a Jupiter mass. Here, we perform simple 1D calculations to show that such very low estimates of the disc mass are an artifact of the specific implementation of the tidal torque in 1D models. In particular, for moderate mass ratios of the...

  1. The High-Mass End of the Black Hole Mass Function: Mass Estimates in Brightest Cluster Galaxies

    CERN Document Server

    Bonta', E Dalla; Corsini, E M; Miralda-Escude', J; Coccato, L; Sarzi, M; Pizzella, A; Beifiori, A

    2008-01-01

    We present Hubble Space Telescope imaging and spectroscopic observations of three Brightest Cluster Galaxies, Abell 1836-BCG, Abell 2052-BCG, and Abell 3565-BCG, obtained with the Wide Field and Planetary Camera 2, the Advanced Camera for Surveys and the Space Telescope Imaging Spectrograph. The data provide detailed information on the structure and mass profile of the stellar component, the dust optical depth, and the spatial distribution and kinematics of the ionized gas within the innermost region of each galaxy. Dynamical models, which account for the observed stellar mass profile and include the contribution of a central supermassive black hole (SBH), are constructed to reproduce the kinematics derived from the Halpha and [N II](lambda 6548,6583) emission lines. Secure SBH detection with M_bh=3.61(+0.41,-0.50)x10^9 M_sun and M_bh=1.34(+0.21,-0.19)x10^9 M_sun, respectively, are obtained for Abell 1836-BCG and Abell 3565-BCG, which show regular rotation curves and strong central velocity gradients. In the ...

  2. Dumb holes: analogues for black holes.

    Science.gov (United States)

    Unruh, W G

    2008-08-28

    The use of sonic analogues to black and white holes, called dumb or deaf holes, to understand the particle production by black holes is reviewed. The results suggest that the black hole particle production is a low-frequency and low-wavenumber process.

  3. Stellar and Black Hole Mass Densities as Empirical Tracers of Co-evolution Show Lock-step Growth since $z{\\sim}3$

    OpenAIRE

    Schindler, Jan-Torge; Fan, Xiaohui; Duschl, Wolfgang J.

    2016-01-01

    At redshifts beyond $z{\\sim}1$ measuring the black hole galaxy relations proves to be a difficult task. The bright light of the AGN aggravates deconvolution of black hole and galaxy properties. On the other hand high redshift data on these relations is vital to understand in what ways galaxies and black holes co-evolve and in what ways they don't. In this work we use black hole (BHMDs) and stellar mass densities (SMDs) to constrain the possible co-evolution of black holes with their host gala...

  4. Recycled pulsars with black hole companions: the high-mass analogues of PSR B2303+46

    NARCIS (Netherlands)

    Sipior, M.S.; Portegies Zwart, S.F.; Nelemans, G.

    2004-01-01

    We investigate the possibility that mass transfer early in the evolution of a massive binary can effect a reversal of the end states of the two components, resulting in a neutron star that forms before a black hole. In this sense, such systems would comprise the high-mass analogues of white dwarf-ne

  5. Determining Central Black Hole Masses in Distant Active Galaxies and Quasars. II. Improved Optical and UV Scaling Relationships

    DEFF Research Database (Denmark)

    Vestergaard, Marianne; Peterson, B. M.

    2006-01-01

    We present four improved empirical relationships useful for estimating the central black hole mass in nearby AGNs and distant luminous quasars alike using either optical or UV single-epoch spectroscopy. These mass-scaling relationships between line widths and luminosity are based on recently...

  6. Penrose inequalities and a positive mass theorem for charged black holes in higher dimensions

    Science.gov (United States)

    Lopes de Lima, Levi; Girão, Frederico; Lozório, Weslley; Silva, Juscelino

    2016-02-01

    We use the inverse mean curvature flow to establish Penrose-type inequalities for time-symmetric Einstein-Maxwell initial data sets which can be suitably embedded as a hypersurface in Euclidean space {{{R}}}n+1, n≥slant 3. In particular, we prove a positive mass theorem for this class of charged black holes. As an application, we show that the conjectured upper bound for the area in terms of the mass and the charge, which in dimension n = 3 is relevant in connection with the cosmic censorship conjecture, always holds under the natural assumption that the horizon is stable as a minimal hypersurface. The first and second authors were partially supported by CNPq/Brazil grants. The first and last authors were partially supported by a CAPES/Brazil grant.

  7. Erratic Black Hole Regulates Itself

    Science.gov (United States)

    2009-03-01

    New results from NASA's Chandra X-ray Observatory have made a major advance in explaining how a special class of black holes may shut off the high-speed jets they produce. These results suggest that these black holes have a mechanism for regulating the rate at which they grow. Black holes come in many sizes: the supermassive ones, including those in quasars, which weigh in at millions to billions of times the mass of the Sun, and the much smaller stellar-mass black holes which have measured masses in the range of about 7 to 25 times the Sun's mass. Some stellar-mass black holes launch powerful jets of particles and radiation, like seen in quasars, and are called "micro-quasars". The new study looks at a famous micro-quasar in our own Galaxy, and regions close to its event horizon, or point of no return. This system, GRS 1915+105 (GRS 1915 for short), contains a black hole about 14 times the mass of the Sun that is feeding off material from a nearby companion star. As the material swirls toward the black hole, an accretion disk forms. This system shows remarkably unpredictable and complicated variability ranging from timescales of seconds to months, including 14 different patterns of variation. These variations are caused by a poorly understood connection between the disk and the radio jet seen in GRS 1915. Chandra, with its spectrograph, has observed GRS 1915 eleven times since its launch in 1999. These studies reveal that the jet in GRS 1915 may be periodically choked off when a hot wind, seen in X-rays, is driven off the accretion disk around the black hole. The wind is believed to shut down the jet by depriving it of matter that would have otherwise fueled it. Conversely, once the wind dies down, the jet can re-emerge. "We think the jet and wind around this black hole are in a sort of tug of war," said Joseph Neilsen, Harvard graduate student and lead author of the paper appearing in the journal Nature. "Sometimes one is winning and then, for reasons we don

  8. Black hole information vs. locality

    CERN Document Server

    Itzhaki, N

    1996-01-01

    We discuss the limitations on space time measurement in Schwarzchild metric. We find that near the horizon the limitations on space time measurement are of the order of the black hole radius. We suggest that it indicates that a large mass black hole can not be described by means of local field theory even at macroscopic distances and that any attempt to describe black hole formation and evaporation by means of an effective local field theory will necessarily lead to information loss. We also present a new interpretation of the black hole entropy which leads to S=cA , where c is a constant of order 1 which does not depend on the number of fields.

  9. Black hole accretion disc impacts

    CERN Document Server

    Pihajoki, Pauli

    2015-01-01

    We present an analytic model for computing the luminosity and spectral evolution of flares caused by a supermassive black hole impacting the accretion disc of another supermassive black hole. Our model includes photon diffusion, emission from optically thin regions and relativistic corrections to the observed spectrum and time-scales. We test the observability of the impact scenario with a simulated population of quasars hosting supermassive black hole binaries. The results indicate that for a moderate binary mass ratio of 0.3, and impact distances of 100 primary Schwarzschild radii, the accretion disc impacts can be expected to equal or exceed the host quasar in brightness at observed wavelength {\\lambda} = 510 nm up to z = 0.6. We conclude that accretion disc impacts may function as an independent probe for supermassive black hole binaries. We release the code used for computing the model light curves to the community.

  10. Asymmetric black dyonic holes

    Directory of Open Access Journals (Sweden)

    I. Cabrera-Munguia

    2015-04-01

    Full Text Available A 6-parametric asymptotically flat exact solution, describing a two-body system of asymmetric black dyons, is studied. The system consists of two unequal counterrotating Kerr–Newman black holes, endowed with electric and magnetic charges which are equal but opposite in sign, separated by a massless strut. The Smarr formula is generalized in order to take into account their contribution to the mass. The expressions for the horizon half-length parameters σ1 and σ2, as functions of the Komar parameters and of the coordinate distance, are displayed, and the thermodynamic properties of the two-body system are studied. Furthermore, the seven physical parameters satisfy a simple algebraic relation which can be understood as a dynamical scenario, in which the physical properties of one body are affected by the ones of the other body.

  11. Evolution of supermassive black holes

    CERN Document Server

    Volonteri, M

    2006-01-01

    Supermassive black holes (SMBHs) are nowadays believed to reside in most local galaxies, and the available data show an empirical correlation between bulge luminosity - or stellar velocity dispersion - and black hole mass, suggesting a single mechanism for assembling black holes and forming spheroids in galaxy halos. The evidence is therefore in favour of a co-evolution between galaxies, black holes and quasars. In cold dark matter cosmogonies, small-mass subgalactic systems form first to merge later into larger and larger structures. In this paradigm galaxy halos experience multiple mergers during their lifetime. If every galaxy with a bulge hosts a SMBH in its center, and a local galaxy has been made up by multiple mergers, then a black hole binary is a natural evolutionary stage. The evolution of the supermassive black hole population clearly has to be investigated taking into account both the cosmological framework and the dynamical evolution of SMBHs and their hosts. The seeds of SMBHs have to be looked ...

  12. Black holes in the milky way galaxy.

    Science.gov (United States)

    Filippenko, A V

    1999-08-31

    Extremely strong observational evidence has recently been found for the presence of black holes orbiting a few relatively normal stars in our Milky Way Galaxy and also at the centers of some galaxies. The former generally have masses of 4-16 times the mass of the sun, whereas the latter are "supermassive black holes" with millions to billions of solar masses. The evidence for a supermassive black hole in the center of our galaxy is especially strong.

  13. A Search for Stellar-Mass Black Holes via Astrometric Microlensing

    CERN Document Server

    Lu, J R; Ofek, E O; Udalski, A; Kozlowski, S

    2016-01-01

    While dozens of stellar mass black holes have been discovered in binary systems, isolated black holes have eluded detection. Their presence can be inferred when they lens light from a background star. We attempt to detect the astrometric lensing signatures of three photometrically identified microlensing events, OGLE-2011-BLG-0022, OGLE-2011-BLG-0125, and OGLE-2012-BLG-0169 (OB110022, OB110125, and OB120169), located toward the Galactic Bulge. These events were selected because of their long durations, which statistically favors more massive lenses. Astrometric measurements were made over 1-2 years using laser-guided adaptive optics observations from the W. M. Keck Observatory. Lens model parameters were first constrained by the photometric light curves. The OB120169 light curve is well-fit by a single-lens model, while both OB110022 and OB110125 light curves favor binary-lens models. Using the photometric fits as prior information, no significant astrometric lensing signal was detected and all targets were c...

  14. Ultraluminous X-ray Sources as Intermediate Mass Black Holes Fed by Tidally Captured Stars

    CERN Document Server

    Hopman, C; Alexander, T; Hopman, Clovis; Zwart, Simon F. Portegies; Alexander, Tal

    2004-01-01

    The nature of ultraluminous X-ray sources (ULXs) is presently unknown. A possible explanation is that they are accreting intermediate mass black holes (IBHs) that are fed by Roche lobe overflow from a tidally captured stellar companion. We show that a star can circularize around an IBH without being destroyed by tidal heating (in contrast to the case of M_bh> 10^6 M_sun massive black holes in galactic centers, where survival is unlikely). We find that the capture and circularization rate is of the order of 5 \\times 10^-8 yr^-1, almost independently of the cluster's relaxation time. We follow the luminosity evolution of the binary system during the main sequence Roche lobe overflow phase and show it can maintain ULX-like luminosities for >10 Myr. In particular, we show that the ULX in the young cluster MGG-11 in star-burst galaxy M82, which possibly harbors an IBH, is well explained by this mechanism, and we predict that \\gtrsim 10% of similar clusters with IBHs have a tidally captured circularized star. The c...

  15. Prompt emission from tidal disruptions of white dwarfs by intermediate mass black holes

    Directory of Open Access Journals (Sweden)

    Laguna P.

    2012-12-01

    Full Text Available We present a qualitative picture of prompt emission from tidal disruptions of white dwarfs (WD by intermediate mass black holes (IMBH. The smaller size of an IMBH compared to a supermassive black hole and a smaller tidal radius of a WD disruption lead to a very fast event with high peak luminosity. Magnetic field is generated in situ following the tidal disruption, which leads to effective accretion. Since large-scale magnetic field is also produced, geometrically thick super-Eddington inflow leads to a relativistic jet. The dense jet possesses a photosphere, which emits quasi-thermal radiation in soft X-rays. The source can be classified as a long low-luminosity gamma-ray burst (ll-GRB. Tidal compression of a WD causes nuclear ignition, which is observable as an accompanying supernova. We suggest that GRB060218 and SN2006aj is such a pair of ll-GRB and supernova. We argue that in a flux-limited sample the disruptions of WDs by IMBHs are more frequent then the disruptions of other stars by IMBHs.

  16. Intermediate mass black holes in AGN disks II. Model predictions & observational constraints

    CERN Document Server

    McKernan, B; Kocsis, B; Lyra, W; Winter, L M

    2014-01-01

    If intermediate mass black holes (IMBHs) grow efficiently in gas disks around supermassive black holes, their host active galactic nucleus (AGN) disks should exhibit myriad observational signatures. Gap-opening IMBHs in AGN disks can exhibit spectral features and variability analagous to gapped protoplanetary disks. A gap-opening IMBH in the innermost disk imprints ripples and oscillations on the broad Fe K$\\alpha$ line which may be detectable with future X-ray missions. A non-gap-opening IMBH will accrete and produce a soft X-ray excess relative to continuum emission. An IMBH on a retrograde orbit in an AGN disk will not open a gap and will generate soft X-rays from a bow-shock 'headwind'. Accreting IMBH in a large cavity can generate ULX-like X-ray luminosities and LINER-like optical line ratios from local ionized gas. We propose that many LINERs house a weakly accreting MBH binary in a large central disk cavity and will be luminous sources of gravitational waves (GW). IMBHs in galactic nuclei may also be d...

  17. Synthetic extinction maps around intermediate-mass black holes in Galactic globular clusters

    CERN Document Server

    Pepe, C

    2016-01-01

    During the last decades, much effort has been devoted to explain the discrepancy between the amount of intracluster medium (ICM) estimated from stellar evolution theories and that emerging from observations in globular clusters (GCs). One possible scenario is the accretion of this medium by an intermediate-mass black hole (IMBH) at the centre of the cluster. In this work, we aim at modelling the cluster colour-excess profile as a tracer of the ICM density, both with and without an IMBH. Comparing the profiles with observations allows us to test the existence of IMBHs and their possible role in the cleansing of the ICM. We derive the intracluster density profiles from hydrodynamical models of accretion onto a central IMBH in a GC and we determine the corresponding dust density. This model is applied to a list of 25 Galactic GCs. We find that central IMBHs decrease the ICM by several orders of magnitude. In a subset of 9 clusters, the absence of the black hole combined with a low intracluster medium temperature...

  18. Inspiral, merger and ring-down of equal-mass black-hole binaries

    CERN Document Server

    Buonanno, A; Pretorius, F; Buonanno, Alessandra; Cook, Gregory B.; Pretorius, Frans

    2006-01-01

    We investigate the dynamics and gravitational-wave (GW) emission in the binary merger of equal-mass black holes as obtained from numerical relativity simulations. Results from the evolution of three sets of initial data are explored in detail, corresponding to different initial separations of the black holes. We find that to a good approximation the inspiral phase of the evolution is quasi-circular, followed by a "blurred, quasi-circular plunge", then merger and ring down. We present first-order comparisons between analytical models of the various stages of the merger and the numerical results. We provide comparisons between the numerical results and analytical predictions based on the adiabatic Newtonain, post-Newtonian (PN), and non-adiabatic resummed-PN models. From the ring-down portion of the GW we extract the fundamental quasi-normal mode and several of the overtones. Finally, we estimate the optimal signal-to-noise ratio for typical binaries detectable by GW experiments.

  19. An ultraluminous quasar with a twelve-billion-solar-mass black hole at redshift 6.30.

    Science.gov (United States)

    Wu, Xue-Bing; Wang, Feige; Fan, Xiaohui; Yi, Weimin; Zuo, Wenwen; Bian, Fuyan; Jiang, Linhua; McGreer, Ian D; Wang, Ran; Yang, Jinyi; Yang, Qian; Thompson, David; Beletsky, Yuri

    2015-02-26

    So far, roughly 40 quasars with redshifts greater than z = 6 have been discovered. Each quasar contains a black hole with a mass of about one billion solar masses (10(9) M Sun symbol). The existence of such black holes when the Universe was less than one billion years old presents substantial challenges to theories of the formation and growth of black holes and the coevolution of black holes and galaxies. Here we report the discovery of an ultraluminous quasar, SDSS J010013.02+280225.8, at redshift z = 6.30. It has an optical and near-infrared luminosity a few times greater than those of previously known z > 6 quasars. On the basis of the deep absorption trough on the blue side of the Lyman-α emission line in the spectrum, we estimate the proper size of the ionized proximity zone associated with the quasar to be about 26 million light years, larger than found with other z > 6.1 quasars with lower luminosities. We estimate (on the basis of a near-infrared spectrum) that the black hole has a mass of ∼1.2 × 10(10) M Sun symbol, which is consistent with the 1.3 × 10(10) M Sun symbol derived by assuming an Eddington-limited accretion rate.

  20. Could supermassive black holes be quintessential primordial black holes?

    CERN Document Server

    Bean, R; Bean, Rachel; Magueijo, Joao

    2002-01-01

    There is growing observational evidence for a population of supermassive black holes (SMBHs) in galactic bulges. We examine in detail the conditions under which these black holes must have originated from primordial black holes (PBHs). We consider the merging and accretion history experienced by SMBHs to find that, whereas it is possible that they were formed by purely astrophysical processes, this is unlikely and most probably a populations of primordial progenitors is necessary. We identify the mass distribution and comoving density of this population and then propose a cosmological scenario producing PBHs with the right properties. Although this is not essential we consider PBHs produced at the end of a period of inflation with a blue spectrum of fluctuations. We constrain the value of the spectral tilt in order to obtain the required PBH comoving density. We then assume that PBHs grow by accreting quintessence showing that their mass scales like the horizon mass while the quintessence field itself is scal...

  1. Magnetic massive stars as progenitors of `heavy' stellar-mass black holes

    Science.gov (United States)

    Petit, V.; Keszthelyi, Z.; MacInnis, R.; Cohen, D. H.; Townsend, R. H. D.; Wade, G. A.; Thomas, S. L.; Owocki, S. P.; Puls, J.; ud-Doula, A.

    2017-04-01

    The groundbreaking detection of gravitational waves produced by the inspiralling and coalescence of the black hole (BH) binary GW150914 confirms the existence of 'heavy' stellar-mass BHs with masses >25 M⊙. Initial characterization of the system by Abbott et al. supposes that the formation of BHs with such large masses from the evolution of single massive stars is only feasible if the wind mass-loss rates of the progenitors were greatly reduced relative to the mass-loss rates of massive stars in the Galaxy, concluding that heavy BHs must form in low-metallicity (Z ≲ 0.25-0.5 Z⊙) environments. However, strong surface magnetic fields also provide a powerful mechanism for modifying mass-loss and rotation of massive stars, independent of environmental metallicity. In this paper, we explore the hypothesis that some heavy BHs, with masses >25 M⊙ such as those inferred to compose GW150914, could be the natural end-point of evolution of magnetic massive stars in a solar-metallicity environment. Using the MESA code, we developed a new grid of single, non-rotating, solar-metallicity evolutionary models for initial zero-age main sequence masses from 40 to 80 M⊙ that include, for the first time, the quenching of the mass-loss due to a realistic dipolar surface magnetic field. The new models predict terminal-age main-sequence (TAMS) masses that are significantly greater than those from equivalent non-magnetic models, reducing the total mass lost by a strongly magnetized 80 M⊙ star during its main-sequence evolution by 20 M⊙. This corresponds approximately to the mass-loss reduction expected from an environment with metallicity Z = 1/30 Z⊙.

  2. Thermal BEC Black Holes

    Directory of Open Access Journals (Sweden)

    Roberto Casadio

    2015-10-01

    Full Text Available We review some features of Bose–Einstein condensate (BEC models of black holes obtained by means of the horizon wave function formalism. We consider the Klein–Gordon equation for a toy graviton field coupled to a static matter current in a spherically-symmetric setup. The classical field reproduces the Newtonian potential generated by the matter source, while the corresponding quantum state is given by a coherent superposition of scalar modes with a continuous occupation number. An attractive self-interaction is needed for bound states to form, the case in which one finds that (approximately one mode is allowed, and the system of N bosons can be self-confined in a volume of the size of the Schwarzschild radius. The horizon wave function formalism is then used to show that the radius of such a system corresponds to a proper horizon. The uncertainty in the size of the horizon is related to the typical energy of Hawking modes: it decreases with the increasing of the black hole mass (larger number of gravitons, resulting in agreement with the semiclassical calculations and which does not hold for a single very massive particle. The spectrum of these systems has two components: a discrete ground state of energy m (the bosons forming the black hole and a continuous spectrum with energy ω > m (representing the Hawking radiation and modeled with a Planckian distribution at the expected Hawking temperature. Assuming the main effect of the internal scatterings is the Hawking radiation, the N-particle state can be collectively described by a single-particle wave-function given by a superposition of a total ground state with energy M = Nm and Entropy 2015, 17 6894 a Planckian distribution for E > M at the same Hawking temperature. This can be used to compute the partition function and to find the usual area law for the entropy, with a logarithmic correction related to the Hawking component. The backreaction of modes with ω > m is also shown to reduce

  3. The origin of Black-Hole Spin in Galactic Low-Mass X-ray Binaries

    Science.gov (United States)

    Fragos, Tassos; McClintock, Jeffrey

    2015-08-01

    Galactic field low-mass X-ray binaries (LMXBs), like the ones for which black hole (BH) spin measurements are available, are believed to form in situ via the evolution of isolated binaries. In the standard formation channel, these systems survived a common envelope phase, after which the remaining helium core of the primary star and the subsequently formed BH are not expected to be highly spinning. However, the measured spins of BHs in LMXBs cover the whole range of spin parameters from a*~0 to a*1. In this talk I propose that the BH spin in LMXBs is acquired through accretion onto the BH during its long stable accretion phase. In order to test this hypothesis, I calculated extensive grids of binary evolutionary sequences in which a BH accretes matter from a close companion. For each evolutionary sequence, I examined whether, at any point in time, the calculated binary properties are in agreement with their observationally inferred counterparts of observed Galactic LMXBs with BH spin measurements. Mass-transfer sequences that simultaneously satisfy all observational constraints represent possible progenitors of the considered LMXBs and thus give estimates of the amount of matter that the BH has accreted since the onset of Roche-Lobe overflow. I find that in all Galactic LMXBs with measured BH spin, the origin of the spin can be accounted by the accreted matter. Furthermore, based on this hypothesis, I derive limits on the maximum spin that a BH can have depending on the orbital period of the binary it resides in, and give predictions on the maximum possible BH spin of Galactic LMXBs where a BH spin measurement is not yet available. Finally I will discuss the implication that our findings have on the birth black hole mass distribution.

  4. Powerful Radio Emission From Low-mass Supermassive Black Holes Favors Disk-like Bulges

    CERN Document Server

    Wang, J; Xu, D W; Wei, J Y

    2016-01-01

    The origin of spin of low-mass supermassive black hole (SMBH) is still a puzzle at present. We here report a study on the host galaxies of a sample of radio-selected nearby ($z<0.05$) Seyfert 2 galaxies with a BH mass of $10^{6-7} M_\\odot$. By modeling the SDSS $r$-band images of these galaxies through a 2-dimensional bulge+disk decomposition, we identify a new dependence of SMBH's radio power on host bulge surface brightness profile, in which more powerful radio emission comes from a SMBH associated with a more disk-like bulge. This result means low-mass and high-mass SMBHs are spun up by two entirely different modes that correspond to two different evolutionary paths. A low-mass SMBH is spun up by a gas accretion with significant disk-like rotational dynamics of the host galaxy in the secular evolution, while a high-mass one by a BH-BH merger in the merger evolution.

  5. On the Formation of Galactic Black Hole Low-Mass X-ray Binaries

    CERN Document Server

    Wang, Chen; Li, Xiang-Dong

    2016-01-01

    Currently, there are 24 black hole (BH) X-ray binary systems that have been dynamically confirmed in the Galaxy. Most of them are low-mass X-ray binaries (LMXBs) comprised of a stellar-mass BH and a low-mass donor star. Although the formation of these systems has been extensively investigated, some crucial issues remain unresolved. The most noticeable one is that, the low-mass companion has difficulties in ejecting the tightly bound envelope of the massive primary during the spiral-in process. While initially intermediate-mass binaries are more likely to survive the common envelope (CE) evolution, the resultant BH LMXBs mismatch the observations. In this paper, we use both stellar evolution and binary population synthesis to study the evolutionary history of BH LMXBs. We test various assumptions and prescriptions for the supernova mechanisms that produce BHs, the binding energy parameter, the CE efficiency, and the initial mass distributions of the companion stars. We obtain the birthrate and the distribution...

  6. Dynamical Formation of Low-mass Merging Black Hole Binaries like GW151226

    Science.gov (United States)

    Chatterjee, Sourav; Rodriguez, Carl L.; Kalogera, Vicky; Rasio, Frederic A.

    2017-02-01

    Using numerical models for star clusters spanning a wide range in ages and metallicities (Z) we study the masses of binary black holes (BBHs) produced dynamically and merging in the local universe (z ≲ 0.2). After taking into account cosmological constraints on star formation rate and metallicity evolution, which realistically relate merger delay times obtained from models with merger redshifts, we show here for the first time that while old, metal-poor globular clusters can naturally produce merging BBHs with heavier components, as observed in GW150914, lower-mass BBHs like GW151226 are easily formed dynamically in younger, higher-metallicity clusters. More specifically, we show that the mass of GW151226 is well within 1σ of the mass distribution obtained from our models for clusters with Z/Z⊙ ≳ 0.5. Indeed, dynamical formation of a system like GW151226 likely requires a cluster that is younger and has a higher metallicity than typical Galactic globular clusters. The LVT151012 system, if real, could have been created in any cluster with Z/Z⊙ ≲ 0.25. On the other hand, GW150914 is more massive (beyond 1σ) than typical BBHs from even the lowest-metallicity (Z/Z⊙ = 0.005) clusters we consider, but is within 2σ of the intrinsic mass distribution from our cluster models with Z/Z⊙ ≲ 0.05 of course, detection biases also push the observed distributions toward higher masses.

  7. The typical mass ratio and typical final spin in supermassive black hole mergers

    CERN Document Server

    Gergely, László Á

    2012-01-01

    We prove that merging supermassive black holes (SMBHs) typically have neither equal masses, nor is their mass ratio too extreme. The majority of such mergers fall into the mass ratio range of 1:30 to 1:3, implying a spin flip during the inspiral. We also present a simple expression for the final spin $\\chi_{f}$ of the emerging SMBH, as function of the mass ratio, initial spin magnitudes, and orientation of the spins with respect to the orbital plane and each other. This formula approximates well more cumbersome expressions obtained from the fit with numerical simulations. By integrating over all equally likely orientations for precessing mergers we determine a lower approximant to the final spin distribution as function of the mass ratio alone. By folding this with the derived mass ratio dependent merger rate we derive a lower bound to the typical final spin value after mergers. We repeat the procedure deriving an upper bound for the typical spin in the case when the spins are aligned to the orbital angular m...

  8. Surfing a Black Hole

    Science.gov (United States)

    2002-10-01

    Star Orbiting Massive Milky Way Centre Approaches to within 17 Light-Hours [1] Summary An international team of astronomers [2], lead by researchers at the Max-Planck Institute for Extraterrestrial Physics (MPE) , has directly observed an otherwise normal star orbiting the supermassive black hole at the center of the Milky Way Galaxy. Ten years of painstaking measurements have been crowned by a series of unique images obtained by the Adaptive Optics (AO) NAOS-CONICA (NACO) instrument [3] on the 8.2-m VLT YEPUN telescope at the ESO Paranal Observatory. It turns out that earlier this year the star approached the central Black Hole to within 17 light-hours - only three times the distance between the Sun and planet Pluto - while travelling at no less than 5000 km/sec . Previous measurements of the velocities of stars near the center of the Milky Way and variable X-ray emission from this area have provided the strongest evidence so far of the existence of a central Black Hole in our home galaxy and, implicitly, that the dark mass concentrations seen in many nuclei of other galaxies probably are also supermassive black holes. However, it has not yet been possible to exclude several alternative configurations. In a break-through paper appearing in the research journal Nature on October 17th, 2002, the present team reports their exciting results, including high-resolution images that allow tracing two-thirds of the orbit of a star designated "S2" . It is currently the closest observable star to the compact radio source and massive black hole candidate "SgrA*" ("Sagittarius A") at the very center of the Milky Way. The orbital period is just over 15 years. The new measurements exclude with high confidence that the central dark mass consists of a cluster of unusual stars or elementary particles, and leave little doubt of the presence of a supermassive black hole at the centre of the galaxy in which we live . PR Photo 23a/02 : NACO image of the central region of the Milky Way

  9. Black Hole Decay as Geodesic Motion

    CERN Document Server

    Sen-Gupta, K; Gupta, Kumar S.; Sen, Siddhartha

    2003-01-01

    We show that a formalism for analyzing the near-horizon conformal symmetry of Schwarzschild black holes using a scalar field probe is capable of describing black hole decay. The decay rate is shown to be correctly described by geodesic motion in the space of black hole masses. This provides a novel geometric interpretation for the decay of black holes. We also show that the near-horizon conformal symmetry predicts a precise correction term to the usual expression for the decay rate of black holes. The results obtained here are a consequence of the holographic nature of the system.

  10. Black holes new horizons

    CERN Document Server

    Hayward, Sean Alan

    2013-01-01

    Black holes, once just fascinating theoretical predictions of how gravity warps space-time according to Einstein's theory, are now generally accepted as astrophysical realities, formed by post-supernova collapse, or as supermassive black holes mysteriously found at the cores of most galaxies, powering active galactic nuclei, the most powerful objects in the universe. Theoretical understanding has progressed in recent decades with a wider realization that local concepts should characterize black holes, rather than the global concepts found in textbooks. In particular, notions such as trapping h

  11. Scalarized hairy black holes

    Energy Technology Data Exchange (ETDEWEB)

    Kleihaus, Burkhard, E-mail: b.kleihaus@uni-oldenburg.de [Institut für Physik, Universität Oldenburg, Postfach 2503, D-26111 Oldenburg (Germany); Kunz, Jutta [Institut für Physik, Universität Oldenburg, Postfach 2503, D-26111 Oldenburg (Germany); Yazadjiev, Stoytcho [Department of Theoretical Physics, Faculty of Physics, Sofia University, Sofia 1164 (Bulgaria)

    2015-05-11

    In the presence of a complex scalar field scalar–tensor theory allows for scalarized rotating hairy black holes. We exhibit the domain of existence for these scalarized black holes, which is bounded by scalarized rotating boson stars and hairy black holes of General Relativity. We discuss the global properties of these solutions. Like their counterparts in general relativity, their angular momentum may exceed the Kerr bound, and their ergosurfaces may consist of a sphere and a ring, i.e., form an ergo-Saturn.

  12. Scalarized hairy black holes

    Directory of Open Access Journals (Sweden)

    Burkhard Kleihaus

    2015-05-01

    Full Text Available In the presence of a complex scalar field scalar–tensor theory allows for scalarized rotating hairy black holes. We exhibit the domain of existence for these scalarized black holes, which is bounded by scalarized rotating boson stars and hairy black holes of General Relativity. We discuss the global properties of these solutions. Like their counterparts in general relativity, their angular momentum may exceed the Kerr bound, and their ergosurfaces may consist of a sphere and a ring, i.e., form an ergo-Saturn.

  13. Black Hole Entropy

    OpenAIRE

    P. Mitra

    1994-01-01

    In the talk different definitions of the black hole entropy are discussed and compared. It is shown that the Bekenstein-Hawking entropy $S^{BH}$ (defined by the response of the free energy of a system containing a black hole on the change of the temperature) differs from the statistical- mechanical entropy $S^{SM}=-\\mbox{Tr}(\\hat{\\rho}\\ln \\hat{\\rho})$ (defined by counting internal degrees of freedom of a black hole). A simple explanation of the universality of the Bekenstein-Hawking entropy (...

  14. Black hole entropy

    CERN Document Server

    Frolov, V

    1994-01-01

    In the talk different definitions of the black hole entropy are discussed and compared. It is shown that the Bekenstein-Hawking entropy S^{BH} (defined by the response of the free energy of a system containing a black hole on the change of the temperature) differs from the statistical- mechanical entropy S^{SM}=-\\mbox{Tr}(\\hat{\\rho}\\ln \\hat{\\rho}) (defined by counting internal degrees of freedom of a black hole). A simple explanation of the universality of the Bekenstein-Hawking entropy (i.e. its independence of the number and properties of the fields which might contribute to S^{SM}) is given.

  15. Primordial Black Holes

    CERN Document Server

    MacGibbon, Jane H; Linnemann, J T; Marinelli, S S; Stump, D; Tollefson, K

    2015-01-01

    Primordial Black Holes (PBHs) are of interest in many cosmological contexts. PBHs lighter than about 1012 kg are predicted to be directly detectable by their Hawking radiation. This radiation should produce both a diffuse extragalactic gamma-ray background from the cosmologically-averaged distribution of PBHs and gamma-ray burst signals from individual light black holes. The Fermi, Milagro, Veritas, HESS and HAWC observatories, in combination with new burst recognition methodologies, offer the greatest sensitivity for the detection of such black holes or placing limits on their existence.

  16. Spinning a charged dilaton black hole

    CERN Document Server

    Shiraishi, Kiyoshi

    2015-01-01

    A charged dilaton black hole which possesses infinitesimal angular momentum is studied. We find that the gyromagnetic ratio of the dilaton black hole depends not only on the parameter which appears in the interaction between the dilaton and the electric field but also nonlinearly on the ratio of the charge to the mass of the black hole. The moment of inertia for the charged dilaton hole in the limit of infinitesimal angular momentum is also calculated.

  17. Missing Link: Bayesian detection and measurement of intermediate-mass black-hole binaries

    Science.gov (United States)

    Graff, Philip B.; Buonanno, Alessandra; Sathyaprakash, B. S.

    2015-07-01

    We perform Bayesian analysis of gravitational-wave signals from nonspinning, intermediate-mass black-hole binaries (IMBHBs) with observed total mass, Mobs, from 50 M⊙ to 500 M⊙ and mass ratio 1-4 using advanced LIGO and Virgo detectors. We employ inspiral-merger-ringdown waveform models based on the effective-one-body formalism and include subleading modes of radiation beyond the leading (2,2) mode. The presence of subleading modes increases signal power for inclined binaries and allows for improved accuracy and precision in measurements of the masses as well as breaking of degeneracies in distance, orientation and polarization. For low total masses, Mobs≲50 M⊙ , for which the inspiral signal dominates, the observed chirp mass Mobs=Mobsη3 /5 (η being the symmetric mass ratio) is better measured. In contrast, as increasing power comes from merger and ringdown, we find that the total mass Mobs has better relative precision than Mobs. Indeed, at high Mobs (≥300 M⊙ ), the signal resembles a burst and the measurement thus extracts the dominant frequency of the signal that depends on Mobs. Depending on the binary's inclination, at signal-to-noise ratio (SNR) of 12, uncertainties in Mobs can be as large as ˜20 - 25 % while uncertainties in Mobs are ˜50 - 60 % in binaries with unequal masses (those numbers become ˜17 % vs. ˜22 % in more symmetric mass-ratio binaries). Although large, those uncertainties in Mobs will establish the existence of IMBHs. We find that effective-one-body waveforms with subleading modes are essential to confirm a signal's presence in the data, with calculated Bayesian evidences yielding a false alarm probability below 10-5 for SNR ≳9 in Gaussian noise. Our results show that gravitational-wave observations can offer a unique tool to observe and understand the formation, evolution and demographics of IMBHs, which are difficult to observe in the electromagnetic window.

  18. Reaction of Accretion Disks to Abrupt Mass Loss During Binary Black Hole Merger

    CERN Document Server

    O'Neill, Sean M; Bogdanovic, Tamara; Reynolds, Christopher S; Schnittman, Jeremy

    2008-01-01

    The association of an electromagnetic signal with the merger of a pair of supermassive black holes would have many important implications. For example, it would provide new information about gas and magnetic field interactions in dynamical spacetimes as well as a combination of redshift and luminosity distance that would enable precise cosmological tests. A proposal first made by Bode & Phinney (2007) is that because radiation of gravitational waves during the final inspiral and merger of the holes is abrupt and decreases the mass of the central object by a few percent, there will be waves in the disk that can steepen into shocks and thus increase the disk luminosity in a characteristic way. We evaluate this process analytically and numerically. We find that shocks only occur when the fractional mass loss exceeds the half-thickness (h/r) of the disk, hence significant energy release only occurs for geometrically thin disks which are thus at low Eddington ratios. This strongly limits the effective energy r...

  19. Bounds on Black Hole Spins

    CERN Document Server

    Daly, Ruth A

    2009-01-01

    Beam powers and black hole masses of 48 extended radio sources are combined to obtain lower bounds on the spins and magnetic field strengths of supermassive black holes. This is done in the context of the models of Blandford & Znajek (1977) (the 'BZ' model) and Meier (1999); a parameterization for bounds in the context of other models is suggested. The bounds obtained for very powerful classical double radio sources in the BZ model are consistent with black hole spins of order unity for sources at high redshift. The black hole spins are largest for the highest redshift sources and decrease for sources at lower redshift; the sources studied have redshifts between zero and two. Lower power radio sources associated with central dominant galaxies may have black hole spins that are significantly less than one. Combining this analysis with other results suggests that the maximum values of black hole spin associated with powerful radio galaxies decline from values of order unity at a redshift of 2 to values of o...

  20. Formation of the black-hole binary M33 X-7 through mass exchange in a tight massive system.

    Science.gov (United States)

    Valsecchi, Francesca; Glebbeek, Evert; Farr, Will M; Fragos, Tassos; Willems, Bart; Orosz, Jerome A; Liu, Jifeng; Kalogera, Vassiliki

    2010-11-04

    The X-ray source M33 X-7 in the nearby galaxy Messier 33 is among the most massive X-ray binary stellar systems known, hosting a rapidly spinning, 15.65M(⊙) black hole orbiting an underluminous, 70M(⊙) main-sequence companion in a slightly eccentric 3.45-day orbit (M(⊙), solar mass). Although post-main-sequence mass transfer explains the masses and tight orbit, it leaves unexplained the observed X-ray luminosity, the star's underluminosity, the black hole's spin and the orbital eccentricity. A common envelope phase, or rotational mixing, could explain the orbit, but the former would lead to a merger and the latter to an overluminous companion. A merger would also ensue if mass transfer to the black hole were invoked for its spin-up. Here we report simulations of evolutionary tracks which reveal that if M33 X-7 started as a primary body of 85M(⊙)-99M(⊙) and a secondary body of 28M(⊙)-32M(⊙), in a 2.8-3.1-d orbit, its observed properties can be consistently explained. In this model, the main-sequence primary transfers part of its envelope to the secondary and loses the rest in a wind; it ends its life as a ∼16M(⊙) helium star with an iron-nickel core that collapses to a black hole (with or without an accompanying supernova). The release of binding energy, and possibly collapse asymmetries, 'kick' the nascent black hole into an eccentric orbit. Wind accretion explains the X-ray luminosity, and the black-hole spin can be natal.

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

    CERN Document Server

    Bertone, Gianfranco

    2006-01-01

    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.

  2. Reverberation Mapping Measurements of Black Hole Masses in Six Local Seyfert Galaxies

    CERN Document Server

    Denney, K D; Pogge, R W; Adair, A; Atlee, D W; Au-Yong, K; Bentz, M C; Bird, J C; Brokofsky, D J; Chisholm, E; Comins, M L; Dietrich, M; Doroshenko, V T; Eastman, J D; Efimov, Y S; Ewald, S; Ferbey, S; Gaskell, C M; Hedrick, C H; Jackson, K; Klimanov, S A; Klimek, E S; Kruse, A K; Ladéroute, A; Lamb, J B; Leighly, K; Minezaki, T; Nazarov, S V; Onken, C A; Petersen, E A; Peterson, P; Poindexter, S; Sakata, Y; Schlesinger, K J; Sergeev, S G; Skolski, N; Stieglitz, L; Tobin, J J; Unterborn, C; Vestergaard, M; Watkins, A E; Watson, L C; Yoshii, Y

    2010-01-01

    We present the final results from a high sampling rate, multi-month, spectrophotometric reverberation mapping campaign undertaken to obtain either new or improved Hbeta reverberation lag measurements for several relatively low-luminosity AGNs. We have reliably measured thetime delay between variations in the continuum and Hbeta emission line in six local Seyfert 1 galaxies. These measurements are used to calculate the mass of the supermassive black hole at the center of each of these AGNs. We place our results in context to the most current calibration of the broad-line region (BLR) R-L relationship, where our results remove outliers and reduce the scatter at the low-luminosity end of this relationship. We also present velocity-resolved Hbeta time delay measurements for our complete sample, though the clearest velocity-resolved kinematic signatures have already been published.

  3. Flares from Disruptions of White Dwarfs by Intermediate Mass Black Holes

    Science.gov (United States)

    Shcherbakov, Roman; Haas, R.; Bode, T.; Laguna, P.

    2011-05-01

    Tidal disruptions of white dwarfs (WDs) by intermediate mass black holes (IMBHs) may produce detectable electromagnetic/gravitational wave signature. They may provide the evidence for existence of IMBHs. We simulate the disruptions in full numerical general relativity (GR) with MayaKranc + Whisky code combination for several BH spin values. We model X-ray and UV time-dependent spectra from the simulations. Direct emission from hot fallback material is substantial, when the BH spin is aligned with WD orbital angular momentum. However, the fallback material can be completely shielded by large Compton optical depth in a misaligned case. This emphasizes the importance of realistic GR simulations with misaligned spin. Properties of flares from shock breakout region depend less on spin orientation and value. We discuss the prospects of positive identifications of candidates from GALEX and other surveys.

  4. On the black hole masses in ultra-luminous X-ray sources

    Science.gov (United States)

    Zhou, Xin-Lin

    2015-05-01

    Ultra-luminous X-ray sources (ULXs) are off-nuclear X-ray sources in nearby galaxies with X-ray luminosities ⩾ 1039 erg s-1. The measurement of the black hole (BH) masses of ULXs is a long-standing problem. Here we estimate BH masses in a sample of ULXs with XMM-Newton observations using two different mass indicators, the X-ray photon index and X-ray variability amplitude based on the correlations established for active galactic nuclei (AGNs). The BH masses estimated from the two methods are compared and discussed. We find that some extreme high-luminosity (LX > 5 ×1040 erg s-1) ULXs contain the BH of 104-105 M⊙ . The results from X-ray variability amplitude are in conflict with those from X-ray photon indices for ULXs with lower luminosities. This suggests that these ULXs generally accrete at rates different from those of X-ray luminous AGNs, or they have different power spectral densities of X-ray variability. We conclude that most of ULXs accrete at super-Eddington rate, thus harbor stellar-mass BH.

  5. Rates of stellar tidal disruption as probes of the supermassive black hole mass function

    Science.gov (United States)

    Stone, Nicholas C.; Metzger, Brian D.

    2016-01-01

    Rates of stellar tidal disruption events (TDEs) by supermassive black holes (SMBHs) due to two-body relaxation are calculated using a large galaxy sample (N ≈ 200) in order to explore the sensitivity of the TDE rates to observational uncertainties, such as the parametrization of galaxy light profiles and the stellar mass function. The largest uncertainty arises due to the poorly constrained occupation fraction of SMBHs in low-mass galaxies, which otherwise dominate the total TDE rate. The detection rate of TDE flares by optical surveys is calculated as a function of SMBH mass and other observables for several physically motivated models of TDE emission. We also quantify the fraction of galaxies that produce deeply penetrating disruption events. If the majority of the detected events are characterized by super-Eddington luminosities (such as disc winds, or synchrotron radiation from an off-axis relativistic jet), then the measured SMBH mass distribution will tightly constrain the low-end SMBH occupation fraction. If Eddington-limited emission channels dominate, however, then the occupation fraction sensitivity is much less pronounced in a flux-limited survey (although still present in a volume-complete event sample). The SMBH mass distribution of the current sample of TDEs, though highly inhomogeneous and encumbered by selection effects, already suggests that Eddington-limited emission channels dominate. Even our most conservative rate estimates appear to be in tension with much lower observationally inferred TDE rates, and we discuss several possible resolutions to this discrepancy.

  6. A Uniformly Selected Sample of Low-mass Black Holes in Seyfert 1 Galaxies

    CERN Document Server

    Dong, Xiao-Bo; Yuan, Weimin; Wang, Ting-Gui; Fan, Xiaohui; Zhou, Hongyan; Jiang, Ning

    2012-01-01

    We have conducted a systematic search of low-mass black holes (BHs) in active galactic nuclei (AGNs) with broad Halpha emission lines, aiming at building a homogeneous sample that is more complete than previous ones for fainter, less highly accreting sources. For this purpose, we developed a set of elaborate, automated selection procedures and applied it uniformly to the Fourth Data Release of the Sloan Digital Sky Survey. Special attention is given to AGN--galaxy spectral decomposition and emission-line deblending. We define a sample of 309 type 1 AGNs with BH masses in the range $8 \\times 10^4$--$2 \\times 10^6$ \\msun (with a median of $1.2 \\times 10^6$ solar mass), using the virial mass estimator based on the broad Halpha line. About half of our sample of low-mass BHs differs from that of Greene & Ho, with 61 of them discovered here for the first time. Our new sample picks up more AGNs with low accretion rates: the Eddington ratios of the present sample range from $<~0.01$ to ~1, with 30% below 0.1. ...

  7. The runaway growth of intermediate-mass black holes in dense star clusters

    CERN Document Server

    Zwart, S P; Zwart, Simon Portegies; Millan, Stephen L. W. Mc

    2002-01-01

    We study the growth rate of stars via stellar collisions in dense star clusters, calibrating our analytic calculations with direct N-body, simulations of up to 65536 stars, performed on the GRAPE family of computers. We find that star clusters with initial half-mass relaxation times of less than 20Myr are dominated by stellar collisions, the first collisions occurring at or near the point of core collapse. The majority of collisions occur with the same star, resulting in the runaway growth of a supermassive object. This object can grow up to about 0.1% of the mass of the entire star cluster and could manifest itself as an intermediate-mass black hole (IMBH). The phase of runaway growth lasts until mass loss by stellar evolution arrests core collapse. Star clusters older than about 4Myr and with present-day half-mass relaxation times smaller than 80Myr are expected to contain an IMBH. The star cluster may sink to the Galactic center by dynamical friction before stellar evolution starts to dominate the evolutio...

  8. Weighing black holes in the universe

    Institute of Scientific and Technical Information of China (English)

    WU Xue-bing

    2006-01-01

    The determination of the mass of black holes in our universe is crucial to understand their physics nature but is a great challenge to scientists.In this paper Ⅰ briefly review some methods that are currently used to estimate the mass of black holes,especially those in X-ray binary systems and in galactic nuclei.Our recent progress in improving the mass estimates of supermasssive black holes in active galactic nuclei by involving some empirical relations is presented.Finally Ⅰ point out the similarities and common physics in Galactic black hole X-ray binaries and active galactic nuclei,and demonstrate that the black hole mass estimation is very much helpful to understand the accretion physics around black holes.

  9. First Results from the Lick AGN Monitoring Project: The Mass of the Black Hole in Arp 151

    CERN Document Server

    Bentz, Misty C; Barth, Aaron J; Baliber, Nairn; Bennert, Nicola; Canalizo, Gabriela; Filippenko, Alexei V; Ganeshalingam, Mohan; Gates, Elinor L; Greene, Jenny E; Hidas, Marton G; Hiner, Kyle D; Lee, Nicholas; Li, Weidong; Malkan, Matthew A; Minezaki, Takeo; Serduke, Frank J D; Shiode, Joshua H; Silverman, Jeffrey M; Steele, Thea N; Stern, Daniel; Street, Rachel A; Thornton, Carol E; Treu, Tommaso; Wang, Xiaofeng; Woo, Jong-Hak; Yoshii, Yuzuru

    2008-01-01

    We have recently completed a 64-night spectroscopic monitoring campaign at the Lick Observatory 3-m Shane telescope with the aim of measuring the masses of the black holes in 13 nearby (z < 0.05) Seyfert 1 galaxies with expected masses in the range ~10^6-10^7 M_sun. We present here the first results from this project -- the mass of the central black hole in Arp 151. Strong variability throughout the campaign led to an exceptionally clean Hbeta lag measurement in this object of 4.25(+0.68/-0.66) days in the observed frame. Coupled with the width of the Hbeta emission line in the variable spectrum, we determine a black hole mass of (7.1 +/- 1.2)x10^6 M_sun, assuming the Onken et al. normalization for reverberation-based virial masses. We also find velocity-resolved lag information within the Hbeta emission line which clearly shows infalling gas in the Hbeta-emitting region. Further detailed analysis may lead to a full model of the geometry and kinematics of broad line region gas around the central black hole...

  10. A Catalog Sample of Low-mass Galaxies Observed in X-Rays with Central Candidate Black Holes

    Science.gov (United States)

    Nucita, A. A.; Manni, L.; De Paolis, F.; Giordano, M.; Ingrosso, G.

    2017-03-01

    We present a sample of X-ray-selected candidate black holes in 51 low-mass galaxies with z ≤ 0.055 and masses up to 1010 M ⊙ obtained by cross-correlating the NASA-SLOAN Atlas with the 3XMM catalog. We have also searched in the available catalogs for radio counterparts of the black hole candidates and find that 19 of the previously selected sources also have a radio counterpart. Our results show that about 37% of the galaxies of our sample host an X-ray source (associated with a radio counterpart) spatially coincident with the galaxy center, in agreement with other recent works. For these nuclear sources, the X-ray/radio fundamental plane relation allows one to estimate the mass of the (central) candidate black holes, which are in the range of 104–2 × 108 M ⊙ (with a median value of ≃3 × 107 M ⊙ and eight candidates having masses below 107 M ⊙). This result, while suggesting that X-ray emitting black holes in low-mass galaxies may have had a key role in the evolution of such systems, makes it even more urgent to explain how such massive objects formed in galaxies. Of course, dedicated follow-up observations both in the X-ray and radio bands, as well as in the optical, are necessary in order to confirm our results.

  11. Black Holes Shed Light on Galaxy Formation

    Science.gov (United States)

    2000-01-01

    This videotape is comprised of several segments of animations on black holes and galaxy formation, and several segments of an interview with Dr. John Kormendy. The animation segments are: (1) a super massive black hole, (2) Centarus A active black hole found in a collision, (3) galaxy NGC-4261 (active black hole and jet model), (4) galaxy M-32 (orbits of stars are effected by the gravity of the black hole), (5) galaxy M-37 (motion of stars increases as mass of black hole increases), (6) Birth of active galactic nuclei, (7) the collision of two galaxy leads to merger of the black holes, (8) Centarus A and simulation of the collision of 2 galaxies. There are also several segments of an interview with John Kormendy. In these segments he discusses the two most important aspects of his recent black hole work: (1) the correlations between galaxies speed and the mass of the black holes, and (2) the existence of black holes and galactic formation. He also discusses the importance of the Hubble Space Telescope and the Space Telescope Imaging Spectrograph to the study of black holes. He also shows the methodology of processing images from the spectrograph in his office.

  12. Dyonic Non-Abelian Black Holes

    OpenAIRE

    Brihaye, Y.; Hartmann, B.; Kunz, J; Tell, N.

    1999-01-01

    We study static spherically symmetric dyonic black holes in Einstein-Yang-Mills-Higgs theory. As for the magnetic non-abelian black holes, the domain of existence of the dyonic non-abelian black holes is limited with respect to the horizon radius and the dimensionless coupling constant $\\alpha$, which is proportional to the ratio of vector meson mass and Planck mass. At a certain critical value of this coupling constant, $\\hat \\alpha$, the maximal horizon radius is attained. We derive analyti...

  13. Modelling quantum black hole

    CERN Document Server

    Govindarajan, T R

    2016-01-01

    Novel bound states are obtained for manifolds with singular potentials. These singular potentials require proper boundary conditions across boundaries. The number of bound states match nicely with what we would expect for black holes. Also they serve to model membrane mechanism for the black hole horizons in simpler contexts. The singular potentials can also mimic expanding boundaries elegantly, there by obtaining appropriately tuned radiation rates.

  14. Helical superconducting black holes.

    Science.gov (United States)

    Donos, Aristomenis; Gauntlett, Jerome P

    2012-05-25

    We construct novel static, asymptotically five-dimensional anti-de Sitter black hole solutions with Bianchi type-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 a vanishing entropy and approach domain wall solutions that reveal homogenous, nonisotropic dual ground states with an emergent scaling symmetry.

  15. Braneworld black holes

    CERN Document Server

    Gregory, Ruth

    2008-01-01

    In these lectures, I give an introduction to and overview of braneworlds and black holes in the context of warped compactifications. I first describe the general paradigm of braneworlds, and introduce the Randall-Sundrum model. I discuss braneworld gravity, both using perturbation theory, and also non perturbative results. I then discuss black holes on the brane, the obstructions to finding exact solutions, and ways of tackling these difficulties. I describe some known solutions, and conclude with some open questions and controversies.

  16. Black Hole Induced Ejections

    OpenAIRE

    Pelletier, G.

    2004-01-01

    Black Holes generate a particular kind of environments dominated by an accretion flow which concentrates a magnetic field. The interplay of gravity and magnetism creates this paradoxical situation where relativistic ejection is allowed and consequently high energy phenomena take place. Therefore Black Holes, which are very likely at the origin of powerfull astrophysical phenomena such as AGNs, micro- quasars and GRBs where relativistic ejections are observed, are at the heart of high energy a...

  17. How Much Mass Makes a Black Hole? - Astronomers Challenge Current Theories

    Science.gov (United States)

    2010-08-01

    Using ESO's Very Large Telescope, European astronomers have for the first time demonstrated that a magnetar - an unusual type of neutron star - was formed from a star with at least 40 times as much mass as the Sun. The result presents great challenges to current theories of how stars evolve, as a star as massive as this was expected to become a black hole, not a magnetar. This now raises a fundamental question: just how massive does a star really have to be to become a black hole? To reach their conclusions, the astronomers looked in detail at the extraordinary star cluster Westerlund 1 [1], located 16 000 light-years away in the southern constellation of Ara (the Altar). From previous studies (eso0510), the astronomers knew that Westerlund 1 was the closest super star cluster known, containing hundreds of very massive stars, some shining with a brilliance of almost one million suns and some two thousand times the diameter of the Sun (as large as the orbit of Saturn). "If the Sun were located at the heart of this remarkable cluster, our night sky would be full of hundreds of stars as bright as the full Moon," says Ben Ritchie, lead author of the paper reporting these results. Westerlund 1 is a fantastic stellar zoo, with a diverse and exotic population of stars. The stars in the cluster share one thing: they all have the same age, estimated at between 3.5 and 5 million years, as the cluster was formed in a single star-formation event. A magnetar (eso0831) is a type of neutron star with an incredibly strong magnetic field - a million billion times stronger than that of the Earth, which is formed when certain stars undergo supernova explosions. The Westerlund 1 cluster hosts one of the few magnetars known in the Milky Way. Thanks to its home in the cluster, the astronomers were able to make the remarkable deduction that this magnetar must have formed from a star at least 40 times as massive as the Sun. As all the stars in Westerlund 1 have the same age, the star that

  18. Radio emission as a test of the existence of intermediate-mass black holes in globular clusters and dwarf spheroidal galaxies

    NARCIS (Netherlands)

    T.J. Maccarone

    2004-01-01

    We take the established relation between black hole mass, X-ray luminosity and radio luminosity and show that intermediate-mass black holes (IMBHs), such as those predicted to exist at the centres of globular clusters (GCs), will be easily identifiable objects in deep radio observations. We show tha

  19. A Black Hole in Our Galactic Center

    Science.gov (United States)

    Ruiz, Michael J.

    2008-01-01

    An introductory approach to black holes is presented along with astronomical observational data pertaining to the presence of a supermassive black hole at the center of our galaxy. Concepts of conservation of energy and Kepler's third law are employed so students can apply formulas from their physics class to determine the mass of the black hole…

  20. A New Signature of Dark Matter Annihilations: Gamma-Rays from Intermediate-Mass Black Holes

    CERN Document Server

    Bertone, Gianfranco; Silk, J; Bertone, Gianfranco; Zentner, Andrew R.; Silk, Joseph

    2005-01-01

    We study the prospects for detecting gamma-rays from Dark Matter (DM) annihilations in enhancements of the DM density (mini-spikes) around intermediate-mass black holes with masses in the range $10^2 \\lsim M / \\msun \\lsim 10^6$. Focusing on two different IMBH formation scenarios, we show that, for typical values of mass and cross section of common DM candidates, mini-spikes, produced by the adiabatic growth of DM around pregalactic IMBHs, would be bright sources of gamma-rays, which could be easily detected with large field-of-view gamma-ray experiments such as GLAST, and further studied with smaller field-of-view, larger-area experiments like Air Cherenkov Telescopes CANGAROO, HESS, MAGIC and VERITAS. The detection of many gamma-ray sources not associated with a luminous component of the Local Group, and with identical cut-offs in their energy spectra at the mass of the DM particle, would provide a potential smoking-gun signature of DM annihilations and shed new light on the nature of intermediate and superm...

  1. Study of Correlations Between Radio Jet Velocity and Supermassive Black Hole Mass in Active Galaxies

    Directory of Open Access Journals (Sweden)

    Timothy Pennucci

    2006-01-01

    Full Text Available Previous research has shown that numerous characteristics of many host galaxies, such as stellar velocity dispersion and bulge luminosity, are governed by the central supermassive black hole (SMBH. This same SMBH is also thought to be the origin of radio jets propagating outward from the nucleus of these galaxies. It was then hypothesized that the mass of a SMBH influences and correlates with the initial radio jet velocity in active galaxies. Mass and velocity data were collected for 48 radio galaxies but as a result from projection effects due to the nature of active galaxies, apparent transverse velocity replaced intrinsic velocity in this study as the dependent variable. From these transverse velocities, the minimum intrinsic velocities of the radio jets were calculated for further investigation. Three apparent transverse velocity groups arise in the results that may be weakly correlated to SMBH mass. The calculated minimum intrinsic velocity data supports this correlation. These results are qualitative in nature and need to be tested on additional samples. While no direct conclusion can be made, the positive trends produced in this research between SMBH mass and radio jet velocity may later aid in further studies and galactic evolutionary research.

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

    CERN Document Server

    Baldassare, Vivienne; Gallo, Elena; Greene, Jenny

    2015-01-01

    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 ...

  3. Correlations Between Supermassive Black Holes, Velocity Dispersions, and Mass Deficits in Elliptical Galaxies with Cores

    CERN Document Server

    Kormendy, John; 10.1088/0004-637X/691/2/L142

    2009-01-01

    High-dynamic-range surface photometry in a companion paper makes possible accurate measurement of the stellar light deficits L_def and mass deficits M_def associated with the cores of elliptical galaxies. We show that L_def correlates with the velocity dispersion sigma of the host galaxy bulge averaged outside the central region that may be affected by a supermassive black hole (BH). We confirm that L_def correlates with BH mass MBH. Also, the fractional light deficit L_def/L correlates with MBH/M, the ratio of BH mass to the galaxy stellar mass. All three correlations have scatter similar to or smaller than the scatter in the well known correlation between MBH and sigma. The new correlations are remarkable in view of the dichotomy between ellipticals with cores and those with central extra light. Core light deficit correlates closely with MBH and sigma, but extra light does not. This supports the suggestion that extra light Es are made in wet mergers with starbursts whereas core Es are made in dry mergers. A...

  4. Charged Galileon black holes

    Science.gov (United States)

    Babichev, Eugeny; Charmousis, Christos; Hassaine, Mokhtar

    2015-05-01

    We consider an Abelian gauge field coupled to a particular truncation of Horndeski theory. The Galileon field has translation symmetry and couples non minimally both to the metric and the gauge field. When the gauge-scalar coupling is zero the gauge field reduces to a standard Maxwell field. By taking into account the symmetries of the action, we construct charged black hole solutions. Allowing the scalar field to softly break symmetries of spacetime we construct black holes where the scalar field is regular on the black hole event horizon. Some of these solutions can be interpreted as the equivalent of Reissner-Nordstrom black holes of scalar tensor theories with a non trivial scalar field. A self tuning black hole solution found previously is extended to the presence of dyonic charge without affecting whatsoever the self tuning of a large positive cosmological constant. Finally, for a general shift invariant scalar tensor theory we demonstrate that the scalar field Ansatz and method we employ are mathematically compatible with the field equations. This opens up the possibility for novel searches of hairy black holes in a far more general setting of Horndeski theory.

  5. Ultramassive Black Hole Coalescence

    CERN Document Server

    Khan, Fazeel; Berczik, Peter

    2015-01-01

    Although supermassive black holes (SMBHs) correlate well with their host galaxies, there is an emerging view that outliers exist. Henize 2-10, NGC 4889, and NGC1277 are examples of SMBHs at least an order of magnitude more massive than their host galaxy suggests. The dynamical effects of such ultramassive central black holes is unclear. Here, we perform direct N-body simulations of mergers of galactic nuclei where one black hole is ultramassive to study the evolution of the remnant and the black hole dynamics in this extreme regime. We find that the merger remnant is axisymmetric near the center, while near the large SMBH influence radius, the galaxy is triaxial. The SMBH separation shrinks rapidly due to dynamical friction, and quickly forms a binary black hole; if we scale our model to the most massive estimate for the NGC1277 black hole, for example, the timescale for the SMBH separation to shrink from nearly a kiloparsec to less than a parsec is roughly 10 Myr. By the time the SMBHs form a hard binary, gr...

  6. From Schwinger Balls to Black Holes

    CERN Document Server

    Allahbakhshi, Davood

    2016-01-01

    We have shown intriguing similarities between Schwinger balls and black holes. By considering black hole as a gravitational Schwinger ball, we have derived the Bekenstein-Hawking entropy and the first law of black hole thermodynamics as a direct result of the inverse area dependence of the gravitational force. It is also shown that the Planck length is nothing but the gravitational Schwinger length. The relation between the mass and the radius of the black hole is derived by considering the black hole as a Schwinger ball of gravitons. We show how the evolution of the entanglement entropy of the black hole, as Page introduced many years ago, can be obtained by including gravitons in the black hole's evaporation process and using a deformed EPR mechanism. Also this deformed EPR mechanism can solve the information paradox. We show how naive simultaneous usage of Page's argument and equivalence principle leads to firewall problem.

  7. Instability of charged anti-de Sitter black holes

    Science.gov (United States)

    Gwak, Bogeun; Lee, Bum-Hoon; Ro, Daeho

    2016-10-01

    We have studied the instability of charged anti-de Sitter black holes in four- or higher-dimensions under fragmentation. The unstable black holes under fragmentation can be broken into two black holes. Instability depends not only on the mass and charge of the black hole but also on the ratio between the fragmented black hole and its predecessor. We have found that the near extremal black holes are unstable, and Schwarzschild-AdS black holes are stable. These are qualitatively similar to black holes in four dimensions and higher. The detailed instabilities are numerically investigated.

  8. Newborn Black Holes

    Science.gov (United States)

    Science Teacher, 2005

    2005-01-01

    Scientists using NASA's Swift satellite say they have found newborn black holes, just seconds old, in a confused state of existence. The holes are consuming material falling into them while somehow propelling other material away at great speeds. "First comes a blast of gamma rays followed by intense pulses of x-rays. The energies involved are much…

  9. A Revised Broad-line Region Radius and Black Hole Mass for the Narrow-line Seyfert 1 NGC 4051

    DEFF Research Database (Denmark)

    Denney, K. D.; Watson, L. C.; Peterson, B. M.

    2009-01-01

    ) radius and the optical continuum luminosity—the R BLR-L relationship. Our new measurements of the lag time between variations in the continuum and Hß emission line made from spectroscopic monitoring of NGC 4051 lead to a measured BLR radius of R BLR = 1.87+0.54 -0.50 light days and black hole mass of M...

  10. Calabi-Yau Compactification of Type-Iib String and a Mass Formula of the Extreme Black Holes

    Science.gov (United States)

    Suzuki, Hisao

    Recently proposed mechanism of the black hole condensation at conifold singularity in type-II string is an interesting idea from which we can interpret the phase of the universal moduli space of the string vacua. It might also be expected that the true physics is on the conifold singularity after supersymmetry breaking. We derive a mass formula for the extreme black holes caused by the self-dual five-form field strength, which is stable and supersymmetric. It is shown that the formula can be written by the moduli parameters of Calabi-Yau manifold and can be calculated explicitly.

  11. What does a black hole look like?

    CERN Document Server

    Bailyn, Charles D

    2014-01-01

    Emitting no radiation or any other kind of information, black holes mark the edge of the universe--both physically and in our scientific understanding. Yet astronomers have found clear evidence for the existence of black holes, employing the same tools and techniques used to explore other celestial objects. In this sophisticated introduction, leading astronomer Charles Bailyn goes behind the theory and physics of black holes to describe how astronomers are observing these enigmatic objects and developing a remarkably detailed picture of what they look like and how they interact with their surroundings. Accessible to undergraduates and others with some knowledge of introductory college-level physics, this book presents the techniques used to identify and measure the mass and spin of celestial black holes. These key measurements demonstrate the existence of two kinds of black holes, those with masses a few times that of a typical star, and those with masses comparable to whole galaxies--supermassive black holes...

  12. Cosmic censorship inside black holes

    CERN Document Server

    Thorlacius, L

    2006-01-01

    A simple argument is given that a traversable Cauchy horizon inside a black hole is incompatible with unitary black hole evolution. The argument assumes the validity of black hole complementarity and applies to a generic black hole carrying angular momentum and/or charge. In the second part of the paper we review recent work on the semiclassical geometry of two-dimensional charged black holes.

  13. Spectroscopic analysis of stellar mass black-hole mergers in our local universe with ground-based gravitational wave detectors

    Science.gov (United States)

    Bhagwat, Swetha; Brown, Duncan; Ballmer, Stefan

    2017-01-01

    Motivated by the recent discoveries of binary black-hole mergers by the Advanced Laser Interferometer Gravitational-wave Observatory (Advanced LIGO), we investigate the prospects of ground based detectors to perform a spectroscopic analysis of signals emitted during the ringdown of the Kerr black-hole formed by a stellar mass binary black-hole merger. We investigate the detectability and resolvability of the sub-dominant modes l = m = 3, l = m = 4 and l = 2;m = 1. We find that new ground-based facilities such as Einstein Telescope or Cosmic Explorer could measure multiple ringdown modes in over 300 events per year. We also investigate detector tuning for ringdown oriented searches.

  14. Black hole mass measurement using molecular gas kinematics: what ALMA can do

    Science.gov (United States)

    Yoon, Ilsang

    2017-04-01

    We study the limits of the spatial and velocity resolution of radio interferometry to infer the mass of supermassive black holes (SMBHs) in galactic centres using the kinematics of circum-nuclear molecular gas, by considering the shapes of the galaxy surface brightness profile, signal-to-noise ratios (S/Ns) of the position-velocity diagram (PVD) and systematic errors due to the spatial and velocity structure of the molecular gas. We argue that for fixed galaxy stellar mass and SMBH mass, the spatial and velocity scales that need to be resolved increase and decrease, respectively, with decreasing Sérsic index of the galaxy surface brightness profile. We validate our arguments using simulated PVDs for varying beam size and velocity channel width. Furthermore, we consider the systematic effects on the inference of the SMBH mass by simulating PVDs including the spatial and velocity structure of the molecular gas, which demonstrates that their impacts are not significant for a PVD with good S/N unless the spatial and velocity scale associated with the systematic effects are comparable to or larger than the angular resolution and velocity channel width of the PVD from pure circular motion. Also, we caution that a bias in a galaxy surface brightness profile owing to the poor resolution of a galaxy photometric image can largely bias the SMBH mass by an order of magnitude. This study shows the promise and the limits of ALMA observations for measuring SMBH mass using molecular gas kinematics and provides a useful technical justification for an ALMA proposal with the science goal of measuring SMBH mass.

  15. Mass ratio determination from Halpha lines in Black-Hole X-ray transients

    CERN Document Server

    Casares, Jorge

    2016-01-01

    We find that the mass ratio q in quiescent black hole (BH) X-ray transients is tightly correlated with the ratio of the double peak separation (DP) to the full-width-half maximum (FWHM) of the Halpha emission line, log q = -6.88 -23.2 log (DP/FWHM). The correlation is explained through the efficient truncation of the outer disc radius by the 3:1 resonance with the companion star. This is the dominant tidal interaction for extreme mass ratios q=M2/M1<~0.25, the realm of BH (and some neutron star) X-ray transients. Mass ratios can thus be estimated with a typical uncertainty of ~32%, provided that the Halpha profile used to measure DP/FWHM is an orbital phase average. We apply the DP/FWHM-q relation to the three faint BH transients XTE J1650-500, XTE J1859+226 and Swift J1357-0933 and predict q=0.026 (+0.038-0.007), 0.049 (+0.023-0.012) and 0.040 (+0.003-0.005), respectively. This new relation, together with the FWHM-K2 correlation presented in Paper I (casares 2015) allows the extraction of fundamental para...

  16. An Effective Selection Method for Low-Mass Active Black Holes and First Spectroscopic Identification

    CERN Document Server

    Morokuma, Tomoki; Tanaka, Masaomi; Yasuda, Naoki; Furusawa, Hisanori; Taniguchi, Yuki; Kato, Takahiro; Jiang, Ji-an; Nagao, Tohru; Kuncarayakti, Hanindyo; Morokuma-Matsui, Kana; Ikeda, Hiroyuki; Blinnikov, Sergei; Nomoto, Ken'ichi; Kokubo, Mitsuru; Doi, Mamoru

    2016-01-01

    We present a new method to effectively select objects which may be low-mass active black holes (BHs) at galaxy centers using high-cadence optical imaging data, and our first spectroscopic identification of an active 2.7x10^6 Msun BH at z=0.164. This active BH was originally selected due to its rapid optical variability, from a few hours to a day, based on Subaru Hyper Suprime-Cam~(HSC) g-band imaging data taken with 1-hour cadence. Broad and narrow H-alpha and many other emission lines are detected in our optical spectra taken with Subaru FOCAS, and the BH mass is measured via the broad H-alpha emission line width (1,880 km s^{-1}) and luminosity (4.2x10^{40} erg s^{-1}) after careful correction for the atmospheric absorption around 7,580-7,720A. We measure the Eddington ratio to be as low as 0.05, considerably smaller than those in a previous SDSS sample with similar BH mass and redshift, which indicates one of the strong potentials of our Subaru survey. The g-r color and morphology of the extended component...

  17. Mergers of Unequal Mass Galaxies: Supermassive Black Hole Binary Evolution and Structure of Merger Remnants

    CERN Document Server

    Khan, Fazeel Mahmood; Berczik, Peter; Berentzen, Ingo; Just, Andreas; Spurzem, Rainer

    2012-01-01

    Galaxy centers are residing places for Super Massive Black Holes (SMBHs). Galaxy mergers bring SMBHs close together to form gravitationally bound binary systems which, if able to coalesce in less than a Hubble time, would be one of the most promising sources of gravitational waves for the Laser Interferometer Space Antenna (LISA). In spherical galaxy models, SMBH binaries stall at a separation of approximately one parsec, leading to the "final parsec problem" (FPP). On the other hand, it has been shown that merger-induced triaxiality of the remnant in equal-mass mergers is capable of supporting a constant supply of stars on so-called centrophilic orbits that interact with the binary and thus avoid the FPP. In this paper, using a set of direct N-body simulations of mergers of initially spherically symmetric galaxies with different mass ratios, we show that the merger-induced triaxiality is able to drive unequal-mass SMBH binaries to coalescence. The binary hardening rates are high and depend only weakly on the...

  18. Signature of an Intermediate-Mass Black Hole in the Central Molecular Zone of Our Galaxy

    CERN Document Server

    Oka, Tomoharu; Miura, Kodai; Takekawa, Shunya

    2015-01-01

    We mapped the high-velocity compact cloud CO-0.40-0.22 in 21 molecular lines in the 3 mm band using the Nobeyama Radio Observatory 45 m radio telescope. Eighteen lines were detected from CO-0.40-0.22. The map of each detected line shows that this cloud has a compact appearance (d=~3 pc) and extremely broad velocity width (DV=~100 km/s). The mass and kinetic energy of CO-0.40-0.22 are estimated to be 10^{3.6} M_sun and 10^{49.7} erg, respectively. The representative position-velocity map along the major axis shows that CO-0.40-0.22 consists of an intense region with a shallow velocity gradient and a less intense high-velocity wing. Here, we show that this kinematical structure can be attributed to a gravitational kick to the molecular cloud caused by an invisible compact object with a mass of ~10^5 M_sun. Its compactness and the absence of counterparts at other wavelengths suggest that this massive object is an intermediate-mass black hole.

  19. Signature of an Intermediate-mass Black Hole in the Central Molecular Zone of Our Galaxy

    Science.gov (United States)

    Oka, Tomoharu; Mizuno, Reiko; Miura, Kodai; Takekawa, Shunya

    2016-01-01

    We mapped the high-velocity compact cloud CO-0.40-0.22 in 21 molecular lines in the 3 mm band using the Nobeyama Radio Observatory 45 m radio telescope. Eighteen lines were detected from CO-0.40-0.22. The map of each detected line shows that this cloud has a compact appearance (d ≃ 3 pc) and extremely broad velocity width (ΔV ≃ 100 km s-1). The mass and kinetic energy of CO-0.40-0.22 are estimated to be 103.6 M⊙ and 1049.7 erg, respectively. The representative position-velocity map along the major axis shows that CO-0.40-0.22 consists of an intense region with a shallow velocity gradient and a less intense high-velocity wing. Here, we show that this kinematical structure can be attributed to a gravitational kick to the molecular cloud caused by an invisible compact object with a mass of ˜105 M⊙. Its compactness and the absence of counterparts at other wavelengths suggest that this massive object is an intermediate-mass black hole.

  20. Unstable mass-outflows in geometrically thick accretion flows around black holes

    CERN Document Server

    Okuda, Toru

    2015-01-01

    Accretion flows around black holes generally result in mass-outflows that exhibit irregular behavior quite often. Using 2D time-dependent hydrodynamical calculations, we show that the mass-outflow is unstable in the cases of thick accretion flows such as the low angular momentum accretion flow and the advection-dominated accretion flow. For the low angular momentum flow, the inward accreting matter on the equatorial plane interacts with the outflowing gas along the rotational axis and the centrifugally supported oblique shock is formed at the interface of both the flows, when the viscosity parameter $\\alpha$ is as small as $\\alpha \\le 10^{-3}$. The hot and rarefied blobs, which result in the eruptive mass-outflow, are generated in the inner shocked region and grow up toward the outer boundary. The advection-dominated accretion flow attains finally in the form of a torus disc with the inner edge of the disc at $3R_{\\rm g} \\le r \\le 6R_{\\rm g}$ and the center at $6R_ {\\rm g} \\le r \\le 10R_{\\rm g}$, and a series...

  1. A Constraint of Black Hole Mass and the Inner Edge Radius of Relativistic Accretion Disc

    Institute of Scientific and Technical Information of China (English)

    HE Liang; HUANG Chang-Yin; WANG Ding-Xiong

    2011-01-01

    A constraint to black hole(BH)accretion has previously been derived for the inner edge fixed at the innermost stable circular orbit(ISCO) and the innermost bound circular orbit(IBCO). This constraint is referred to as the mass-radius(MR) relation in this study, and the validity of the MR relation is discussed for different cases. It is shown that the product of the BH mass and the inner edge radius decreases monotonically in the accretion process for the inner edge located between IBCO and ISCO. In addition, we discuss the validity of the MR relation by considering the magnetic coupling(MC) effects of a Kerr BH with its surrounding disc. Although theoretically the product of the BH mass and the radius of ISCO increases(decreases) with time for a BH spin greater(less)than some critical value in the MC process, this relation is approximately valid for an Eddington accretion rate persisting for a rather long time, such as more than 10(6) years. Finally ,we discuss the possible application of the MR relation to astrophysics.

  2. The star ingesting luminosity of intermediate mass black holes in globular clusters

    CERN Document Server

    Ramirez-Ruiz, Enrico

    2008-01-01

    The dynamics of stars in the inner regions of nearby globular clusters (GCs) such as M15 and G1 indicate the presence of central concentrated dark masses, and one would like to know whether these are indeed intermediate mass black holes (IMBHs). As the number of surrounding stars, and their motions, are roughly known, the capture rate can be estimated; the question then arises of whether the apparent quiescence of the nuclei of these GCs is compatible with the IMBH's presence. The role of debris from disrupted stars in activating quiescent nuclei of GCs is studied here employing three-dimensional hydrodynamics simulations. It is argued that when individual stars are disrupted, the bulk of the debris would be swallowed or expelled rapidly compared with the interval between successive disruptions. Only a small fraction of the tightly bound mass is likely to be swallowed, yielding radiation with high efficiency, the surplus being expelled in a radiation-driven wind. A transient (predominantly of soft X-ray emiss...

  3. Pregalactic black holes - A new constraint

    Science.gov (United States)

    Barrow, J. D.; Silk, J.

    1979-01-01

    Pregalactic black holes accrete matter in the early universe and produce copious amounts of X radiation. By using observations of the background radiation in the X and gamma wavebands, a strong constraint is imposed upon their possible abundance. If pregalactic black holes are actually present, several outstanding problems of cosmogony can be resolved with typical pregalactic black hole masses of 100 solar masses. Significantly more massive holes cannot constitute an appreciable mass fraction of the universe and are limited by a specific mass-density bound.

  4. Black Hole Growth in Hierarchical Galaxy Formation

    CERN Document Server

    Malbon, R K; Frenk, C S; Lacey, C G; Malbon, Rowena K.

    2006-01-01

    We incorporate a model for black hole growth during galaxy mergers into the semi-analytical galaxy formation model based on Lambda-CDM proposed by Baugh et al. (2005). Our black hole model has one free parameter, which we set by matching the observed zeropoint of the local correlation between black hole mass and bulge luminosity. We present predictions for the evolution with redshift of the relationships between black hole mass and bulge properties. Our simulations reproduce the evolution of the optical luminosity function of quasars. We study the demographics of the black hole population and address the issue of how black holes acquire their mass. We find that the direct accretion of cold gas during starbursts is an important growth mechanism for lower mass black holes and at high redshift. On the other hand, the re-assembly of pre-existing black hole mass into larger units via merging dominates the growth of more massive black holes at low redshift. This prediction could be tested by future gravitational wa...

  5. Force-feeding Black Holes

    CERN Document Server

    Begelman, Mitchell C

    2012-01-01

    We propose that the growth of supermassive black holes is associated mainly with brief episodes of highly super-Eddington infall of gas ("hyperaccretion"). This gas is not swallowed in real time, but forms an envelope of matter around the black hole that can be swallowed gradually, over a much longer timescale. However, only a small fraction of the black hole mass can be stored in the envelope at any one time. We argue that any infalling matter above a few per cent of the hole's mass is ejected as a result of the plunge in opacity at temperatures below a few thousand degrees K, corresponding to the Hayashi track. The speed of ejection of this matter, compared to the velocity dispersion (sigma) of the host galaxy's core, determines whether the ejected matter is lost forever or returns eventually to rejoin the envelope, from which it can be ultimately accreted. The threshold between matter recycling and permanent loss defines a relationship between the maximum black hole mass and sigma that resembles the empiri...

  6. Stellar Velocity Dispersion Measurements in High-Luminosity Quasar Hosts and Implications for the AGN Black Hole Mass Scale

    CERN Document Server

    Grier, C J; Watson, L C; Peterson, B M; Bentz, M C; Dasyra, K M; Dietrich, M; Ferrarese, L; Pogge, R W; Zu, Y

    2013-01-01

    We present new stellar velocity dispersion measurements for four luminous quasars with the NIFS instrument and the ALTAIR laser guide star adaptive optics system on the Gemini North 8-m telescope. Stellar velocity dispersion measurements and measurements of the supermassive black hole masses in luminous quasars are necessary to investigate the coevolution of black holes and galaxies, trace the details of accretion, and probe the nature of feedback. We find that higher-luminosity quasars with higher-mass black holes are not offset with respect to the MBH-sigma relation exhibited by lower-luminosity AGNs with lower-mass black holes, nor do we see correlations with galaxy morphology. As part of this analysis, we have recalculated the virial products for the entire sample of reverberation-mapped AGNs and used these data to redetermine the mean virial factor hfi that places the reverberation data on the quiescent M_BH-sigma relation. With our updated measurements and new additions to the AGN sample, we obtain = 4...

  7. Janus black holes

    Science.gov (United States)

    Bak, Dongsu; Gutperle, Michael; Janik, Romuald A.

    2011-10-01

    In this paper Janus black holes in A dS 3 are considered. These are static solutions of an Einstein-scalar system with broken translation symmetry along the horizon. These solutions are dual to interface conformal field theories at finite temperature. An approximate solution is first constructed using perturbation theory around a planar BTZ blackhole. Numerical and exact solutions valid for all sets of parameters are then found and compared. Using the exact solution the thermodynamics of the system is analyzed. The entropy associated with the Janus black hole is calculated and it is found that the entropy of the black Janus is the sum of the undeformed black hole entropy and the entanglement entropy associated with the defect.

  8. Charged black holes in phantom cosmology

    Energy Technology Data Exchange (ETDEWEB)

    Jamil, Mubasher; Qadir, Asghar; Rashid, Muneer Ahmad [National University of Sciences and Technology, Center for Advanced Mathematics and Physics, Rawalpindi (Pakistan)

    2008-11-15

    In the classical relativistic regime, the accretion of phantom-like dark energy onto a stationary black hole reduces the mass of the black hole. We have investigated the accretion of phantom energy onto a stationary charged black hole and have determined the condition under which this accretion is possible. This condition restricts the mass-to-charge ratio in a narrow range. This condition also challenges the validity of the cosmic-censorship conjecture since a naked singularity is eventually produced due to accretion of phantom energy onto black hole. (orig.)

  9. The presence of intermediate-mass black holes in globular clusters and its connection with extreme horizontal branch stars

    CERN Document Server

    Miocchi, P

    2007-01-01

    By means of a multimass isotropic and spherical model including self-consistently a central intermediate-mass black hole (IMBH), the influence of this object on the morphological and physical properties of globular clusters is investigated in this paper. Confirming recent numerical studies, it is found that a cluster (with mass M) hosting an IMBH (with mass M_BH) shows, outside the black hole gravitational influence region, a core-like profile resembling a King profile with concentration cM. The mass range estimate 12s - 4.8 90 percent). In particular, the presence of a central IMBH could explain why extreme HB stars are observed in M13 and NGC 6388, but not in M3 and 47 Tuc where this object is likely absent according to our analysis.

  10. Seeding Black Holes in Cosmological Simulations

    CERN Document Server

    Taylor, Philip

    2014-01-01

    We present a new model for the formation of black holes in cosmological simulations, motivated by the first star formation. Black holes form from high density peaks of primordial gas, and grow via both gas accretion and mergers. Massive black holes heat the surrounding material, suppressing star formation at the centres of galaxies, and driving galactic winds. We perform an investigation into the physical effects of the model parameters, and obtain a `best' set of these parameters by comparing the outcome of simulations to observations. With this best set, we successfully reproduce the cosmic star formation rate history, black hole mass -- velocity dispersion relation, and the size -- velocity dispersion relation of galaxies. The black hole seed mass is 10^3Msun, which is orders of magnitude smaller than has been used in previous cosmological simulations with active galactic nuclei, but suggests that the origin of the seed black holes is the death of Population III stars.

  11. THE ORIGIN OF BLACK HOLE SPIN IN GALACTIC LOW-MASS X-RAY BINARIES

    Energy Technology Data Exchange (ETDEWEB)

    Fragos, T. [Geneva Observatory, University of Geneva, Chemin des Maillettes 51, 1290 Sauverny (Switzerland); McClintock, J. E., E-mail: anastasios.fragkos@unige.ch [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

    2015-02-10

    Galactic field black hole (BH) low-mass X-ray binaries (LMXBs) are believed to form in situ via the evolution of isolated binaries. In the standard formation channel, these systems survived a common envelope phase, after which the remaining helium core of the primary star and the subsequently formed BH are not expected to be highly spinning. However, the measured spins of BHs in LMXBs cover the whole range of spin parameters. We propose here that the BH spin in LMXBs is acquired through accretion onto the BH after its formation. In order to test this hypothesis, we calculated extensive grids of detailed binary mass-transfer sequences. For each sequence, we examined whether, at any point in time, the calculated binary properties are in agreement with their observationally inferred counterparts of 16 Galactic LMXBs. The ''successful'' sequences give estimates of the mass that the BH has accreted since the onset of Roche-Lobe overflow. We find that in all Galactic LMXBs with measured BH spin, the origin of the spin can be accounted for by the accreted matter, and we make predictions about the maximum BH spin in LMXBs where no measurement is yet available. Furthermore, we derive limits on the maximum spin that any BH can have depending on current properties of the binary it resides in. Finally we discuss the implication that our findings have on the BH birth-mass distribution, which is shifted by ∼1.5 M {sub ☉} toward lower masses, compared to the currently observed one.

  12. A Search For Stellar-mass Black Holes Via Astrometric Microlensing

    Science.gov (United States)

    Lu, J. R.; Sinukoff, E.; Ofek, E. O.; Udalski, A.; Kozlowski, S.

    2016-10-01

    While dozens of stellar-mass black holes (BHs) have been discovered in binary systems, isolated BHs have eluded detection. Their presence can be inferred when they lens light from a background star. We attempt to detect the astrometric lensing signatures of three photometrically identified microlensing events, OGLE-2011-BLG-0022, OGLE-2011-BLG-0125, and OGLE-2012-BLG-0169 (OB110022, OB110125, and OB120169), located toward the Galactic Bulge. These events were selected because of their long durations, which statistically favors more massive lenses. Astrometric measurements were made over one to two years using laser-guided adaptive optics observations from the W. M. Keck Observatory. Lens model parameters were first constrained by the photometric light curves. The OB120169 light curve is well fit by a single-lens model, while both OB110022 and OB110125 light curves favor binary lens models. Using the photometric fits as prior information, no significant astrometric lensing signal was detected and all targets were consistent with linear motion. The significant lack of astrometric signal constrains the lens mass of OB110022 to 0.05-1.79 M ⊙ in a 99.7% confidence interval, which disfavors a BH lens. Fits to OB110125 yielded a reduced Einstein crossing time and insufficient observations during the peak, so no mass limits were obtained. Two degenerate solutions exist for OB120169, which have a lens mass between 0.2-38.8 M ⊙ and 0.4-39.8 M ⊙ for a 99.7% confidence interval. Follow-up observations of OB120169 will further constrain the lens mass. Based on our experience, we use simulations to design optimal astrometric observing strategies and show that with more typical observing conditions the detection of BHs is feasible.

  13. Detecting and Measuring the Masses of Isolated Black Holes and Neutron Stars through Astrometric Microlensing

    Science.gov (United States)

    Sahu, Kailash

    2013-10-01

    We propose a 3-year program of monitoring of 12 fields in the Galactic bulge, containing a total of 1.5 million stars down to V=28. Our primary aim is to detect microlensing events caused by non-luminous isolated black holes {BHs} and neutron stars {NSs} in the Galactic disk and bulge.The unique capability of HST imaging for microlensing observations is the addition of high-precision astrometry, allowing detection of the astrometric shift of the source during the event. Combined with the lens parallax, provided by the HST event light curve, the astrometric shift provides a direct measurement of the lens mass. We will detect 120 microlensing events, of which 45% will show astrometric deflections, leading to direct determinations of the lens masses. Of these, about 18 lenses are expected to be BHs and 14 of them NSs, along with about 22 events due to main-sequence stars.To date, BH and NS masses have been directly measured only in binaries; no isolated BH has been detected unambiguously within our Galaxy. A survey of the scope proposed here is the only means available at present for measuring the mass function of isolated BHs and NSs, and moreover one that is normalized to that of luminous stars. The results will provide a quantitative estimate of the mass content in the form of stellar remnants in the young Galactic disk and old bulge, and important constraints on SN/GRB explosion mechanisms that produce NSs and BHs.Our data will also be useful for other investigations, including a more accurate determination of the microlensing optical depth, faint variable stars, bulge proper motions and kinematics, and a deep luminosity function of the disk and bulge stars.

  14. Binary black hole coalescence in the extreme-mass-ratio limit: testing and improving the effective-one-body multipolar waveform

    CERN Document Server

    Bernuzzi, Sebastiano; Zenginoglu, Anil

    2010-01-01

    We discuss the properties of the effective-one-body (EOB) multipolar gravitational waveform emitted by nonspinning black-hole binaries of masses $\\mu$ and $M$ in the extreme-mass-ratio limit, $\\mu/M=\

  15. Merging Black Holes

    Science.gov (United States)

    Centrella, Joan

    2009-05-01

    The final merger of two black holes is expected to be the strongest gravitational wave source for ground-based interferometers such as LIGO, VIRGO, and GEO600, as well as the space-based LISA. Observing these sources with gravitational wave detectors requires that we know the radiation waveforms they emit. And, when the black holes merge in the presence of gas and magnetic fields, various types of electromagnetic signals may also be produced. Since these mergers take place in regions of extreme gravity, we need to solve Einstein's equations of general relativity on a computer. For more than 30 years, scientists have tried to compute black hole mergers using the methods of numerical relativity. The resulting computer codes have been plagued by instabilities, causing them to crash well before the black holes in the binary could complete even a single orbit. Within the past few years, however, this situation has changed dramatically, with a series of remarkable breakthroughs. This talk will focus on new simulations that are revealing the dynamics and waveforms of binary black hole mergers, and their applications in gravitational wave detection, testing general relativity, and astrophysics.

  16. Charged Galileon black holes

    CERN Document Server

    Babichev, Eugeny; Hassaine, Mokhtar

    2015-01-01

    We consider an Abelian gauge field coupled to a particular truncation of Horndeski theory. The Galileon field has translation symmetry and couples non minimally both to the metric and the gauge field. When the gauge-scalar coupling is zero the gauge field reduces to a standard Maxwell field. By taking into account the symmetries of the action, we construct charged black hole solutions. Allowing the scalar field to softly break symmetries of spacetime we construct black holes where the scalar field is regular on the black hole event horizon. Some of these solutions can be interpreted as the equivalent of Reissner-Nordstrom black holes of scalar tensor theories with a non trivial scalar field. A self tuning black hole solution found previously is extended to the presence of dyonic charge without affecting whatsoever the self tuning of a large positive cosmological constant. Finally, for a general shift invariant scalar tensor theory we demonstrate that the scalar field Ansatz and method we employ are mathematic...

  17. A Transient Black-Hole Low-Mass X-Ray Binary Candidate in Centaurus A

    CERN Document Server

    Sivakoff, Gregory R; Jordán, Andrés; Juett, Adrienne M; Evans, Daniel A; Forman, William R; Hardcastle, Martin J; Sarazin, Craig L; Birkinshaw, Mark; Brassington, Nicola J; Croston, Judith H; Harris, William E; Jones, Christine; Murray, Stephen S; Raychaudhury, Somak; Woodley, Kristin A; Worrall, Diana M

    2008-01-01

    We report the discovery of a bright transient X-ray source, CXOU J132518.2-430304, towards Centaurus A (Cen A) using six new Chandra X-Ray Observatory observations in 2007 March--May. Between 2003 and 2007, its flux has increased by a factor of >770. The source is likely a low-mass X-ray binary in Cen A with unabsorbed 0.3-10 keV band luminosities of (2-3) x 10^{39} erg s^-1 and a transition from the steep-power law state to the thermal state during our observations. CXOU J132518.2-430304 is the most luminous X-ray source in an early-type galaxy with extensive timing information that reveals transience and a spectral state transition. Combined with its luminosity, these properties make this source one of the strongest candidates to date for containing a stellar-mass black hole in an early-type galaxy. Unless this outburst lasts many years, the rate of luminous transients in Cen A is anomalously high compared to other early-type galaxies.

  18. An upper limit on the mass of the black hole in Ursa Minor dwarf galaxy

    CERN Document Server

    Lora, V; Raga, A; Esquivel, A

    2009-01-01

    The well-established correlations between the mass of massive black holes (BHs) in the nuclei of most studied galaxies and various global properties of their hosting galaxy lend support to the idea that dwarf galaxies and globular clusters could also host a BH in their centers. Direct kinematic detection of BHs in dwarf spheroidal (dSph) galaxies are seriously hindered by the small number of stars inside the gravitational influence region of the BH. The aim of this Letter is to establish an upper dynamical limit on the mass of the putative BH in the Ursa Minor (UMi) dSph galaxy. We present direct N-body simulations of the tidal disruption of the dynamical fossil observed in UMi, with and without a massive BH. We find that the observed substructure is incompatible with the presence of a massive BH of (2-3)x10^4 Msun within the core of UMi. These limits are consistent with the extrapolation of the M_{BH}-sigma relation to the M_{BH}<10^6 Msun regime. We also show that the BH may be off-center with respect to...

  19. Radiation pressure force emission line profiles and black hole mass in active galactic nuclei

    CERN Document Server

    Netzer, H

    2010-01-01

    We present a new analysis of the motion of broad line region (BLR) clouds in active galactic nuclei (AGNs) taking into account the combined influence of gravity and radiation pressure force. We calculate cloud orbits under a large range of conditions and include the effect of a changing column density as a function of location. The dependence of radiation pressure force on the level of ionization and the column density are accurately computed. The main results are: a. The mean cloud location r(BLR) and the line widths (FWHMs) are combined in such a way that the simple virial mass estimate, r{BLR} FWHM^2/G, gives a reasonable approximation to the black hole mass M even when radiation pressure force is important. The reason is that L/M rather than L is the main parameter affecting the planar cloud motion. b. Reproducing the observed mean radius, FWHM and intensity of H-beta and CIV 1549 requires at least two different populations of clouds. c. The cloud location is a function of both L^{1/2} and L/M. Given this...

  20. A New Template Family For The Detection Of Gravitational Waves From Comparable Mass Black Hole Binaries

    CERN Document Server

    Porter, Edward K

    2007-01-01

    In order to improve the phasing of the comparable-mass waveform as we approach the last stable orbit for a system, various re-summation methods have been used to improve the standard post-Newtonian waveforms. In this work we present a new family of templates for the detection of gravitational waves from the inspiral of two comparable-mass black hole binaries. These new adiabatic templates are based on re-expressing the derivative of the binding energy and the gravitational wave flux functions in terms of shifted Chebyshev polynomials. The Chebyshev polynomials are a useful tool in numerical methods as they display the fastest convergence of any of the orthogonal polynomials. In this case they are also particularly useful as they eliminate one of the features that plagues the post-Newtonian expansion : The Chebyshev binding energy now has information at all post-Newtonian orders, compared to the post-Newtonian templates which only have integer at full integer orders. In this work, we compare both the post-Newt...

  1. A Tidal Disruption Event in a Nearby Galaxy Hosting an Intermediate Mass Black Hole

    Science.gov (United States)

    Donato, D; Cenko, S. B.; Covino, S.; Troja, E.; Pursimo, T.; Cheung, C. C.; Fox, O.; Kutyrev, A.; Campana, S.; Fugazza, D.; Landt, H.; Butler, N. R.

    2014-01-01

    We report the serendipitous discovery of a bright point source flare in the Abell cluster A1795 with archival EUVE and Chandra observations. Assuming the EUVE emission is associated with the Chandra source, the X-ray 0.5-7 kiloelectronvolt flux declined by a factor of approximately 2300 over a time span of 6 years, following a power-law decay with index approximately equal to 2.44 plus or minus 0.40. The Chandra data alone vary by a factor of approximately 20. The spectrum is well fit by a blackbody with a constant temperature of kiloteslas approximately equal to 0.09 kiloelectronvolts (approximately equal to 10 (sup 6) Kelvin). The flare is spatially coincident with the nuclear region of a faint, inactive galaxy with a photometric redshift consistent at the 1 sigma level with the cluster (redshift = 0.062476).We argue that these properties are indicative of a tidal disruption of a star by a black hole (BH) with log(M (sub BH) / M (sub 1 solar mass)) approximately equal to 5.5 plus or minus 0.5. If so, such a discovery indicates that tidal disruption flares may be used to probe BHs in the intermediate mass range, which are very difficult to study by other means.

  2. Spin–orbit precession for eccentric black hole binaries at first order in the mass ratio

    Science.gov (United States)

    Akcay, Sarp; Dempsey, David; Dolan, Sam R.

    2017-04-01

    We consider spin–orbit (‘geodetic’) precession for a compact binary in strong-field gravity. Specifically, we compute ψ, the ratio of the accumulated spin-precession and orbital angles over one radial period, for a spinning compact body of mass m 1 and spin s 1, with {{s}1}\\ll Gm12/c , orbiting a non-rotating black hole. We show that ψ can be computed for eccentric orbits in both the gravitational self-force and post-Newtonian frameworks, and that the results appear to be consistent. We present a post-Newtonian expansion for ψ at next-to-next-to-leading order, and a Lorenz-gauge gravitational self-force calculation for ψ at first order in the mass ratio. The latter provides new numerical data in the strong-field regime to inform the effective one-body model of the gravitational two-body problem. We conclude that ψ complements the Detweiler redshift z as a key invariant quantity characterizing eccentric orbits in the gravitational two-body problem.

  3. 11-orbit inspiral of a mass ratio 4:1 black-hole binary

    Energy Technology Data Exchange (ETDEWEB)

    Sperhake, U; Sopuerta, C F [Institute of Space Sciences (CSIC-IEEC), Campus UAB, Torre C5 Parells, 08193 Bellaterra (Spain); Bruegmann, B; Mueller, D, E-mail: sperhake@ieec.uab.es [Theoretisch Physikalisches Institut, Friedrich Schiller Universitaet, Max-Wien Platz 1, 07743 Jena (Germany)

    2011-07-07

    We analyse an 11-orbit inspiral of a non-spinning black-hole binary with mass ratio q {identical_to} M{sub 1}/M{sub 2} = 4. The numerically obtained gravitational waveforms are compared with post-Newtonian (PN) predictions including several subdominant multipoles up to multipolar indices (l = 5, m = 5). We find that (i) numerical and post-Newtonian predictions of the phase of the (2, 2) mode accumulate a phase difference of about 0.35 rad at the PN cut-off frequency M{omega} = 0.1 for the Taylor T1 approximant when numerical and PN waveforms are matched over a window in the early inspiral phase; (ii) in contrast to previous studies of equal mass and specific spinning binaries, we find the Taylor T4 approximant to agree less well with numerical results, provided the latter are extrapolated to infinite extraction radius; (iii) extrapolation of gravitational waveforms to infinite extraction radius is particularly important for subdominant multipoles with l {ne} m; (iv) 3PN terms in post-Newtonian multipole expansions significantly improve the agreement with numerical predictions for subdominant multipoles.

  4. Is there a maximum mass for black holes in galactic nuclei?

    CERN Document Server

    Inayoshi, Kohei

    2016-01-01

    The largest observed supermassive black holes (SMBHs) have a mass of M_BH ~ 10^{10} M_sun, nearly independent of redshift, from the local (z~0) to the early (z>6) Universe. We suggest that the growth of SMBHs above a few 10^{10} M_sun is prevented by small-scale accretion physics, independent of the properties of their host galaxies or of cosmology. Growing more massive BHs requires a gas supply rate from galactic scales onto a nuclear region as high as >10^3 M_sun/yr. At such a high accretion rate, most of the gas converts to stars at large radii (~10-100 pc), well before reaching the BH. We adopt a simple model (Thompson et al. 2005) for a star-forming accretion disk, and find that the accretion rate in the sub-pc nuclear region is reduced to the smaller value of at most a few M_sun/yr. This prevents SMBHs from growing above ~10^{11} M_sun in the age of the Universe. Furthermore, once a SMBH reaches a sufficiently high mass, this rate falls below the critical value at which the accretion flow becomes advect...

  5. The universal "heartbeat" oscillations in black hole systems accross the mass-scale

    CERN Document Server

    Wu, Qingwen; Grzedzielski, Mikolaj; Janiuk, Agnieszka; Gu, Wei-Min; Dong, Ai-jun; Cao, Xiao-Feng; You, Bei; Yan, Zhen; Sun, Mou-Yuan

    2016-01-01

    The hyperluminous X-ray source (HLX-1, the peak X-ray luminosity $\\sim 10^{42}\\rm erg\\ s^{-1}$) near the spiral galaxy ESO 243-49 is possibly the best candidate for intermediate mass black hole (IMBH), which underwent recurrent outbursts with a period of $\\sim 400$ days. The physical reason for this quasi-periodic variability is still unclear. We explore the possibility of radiation-pressure instability in accretion disk by modeling the light curve of HLX-1, and find that it can roughly reproduce the duration, period and amplitude of the recurrent outbursts HLX-1 with an IMBH of ~10^5Msun. Our result provides a possible mechanism to explain the recurrent outbursts in HLX-1. We further find a universal correlation between the outburst duration and the bolometric luminosity for the BH sources with a very broad mass range (e.g., X-ray binaries, XRBs, HLX-1 and active galactic nuclei, AGNs), which is roughly consistent with the prediction of radiation-pressure instability of the accretion disk. These results impl...

  6. Viscosity parameter in dissipative accretion flows with mass outflow around black holes

    Science.gov (United States)

    Nagarkoti, Shreeram; Chakrabarti, Sandip K.

    2016-10-01

    Numerical hydrodynamic simulation of inviscid and viscous flows have shown that significant outflows could be produced from the CENtrifugal pressure-supported BOundary Layer or CENBOL of an advective disc. However, this barrier is weakened in presence of viscosity, more so, if there are explicit energy dissipations at the boundary layer itself. We study effects of viscosity and energy dissipation theoretically on the outflow rate and show that, as the viscosity or energy dissipation (or both) rises, the prospect of formation of outflows is greatly reduced, thereby verifying results obtained through observations and numerical simulations. Indeed, we find that in a dissipative viscous flow, shocks in presence of outflows can be produced only if the Shakura-Sunyaev viscosity parameter α is less than 0.2. This is a direct consequence of modification of the Rankine-Hugoniot relation across the shock in a viscous flow, when the energy dissipation and mass-loss in the form of outflows from the post-shock region are included. If we ignore the effects of mass-loss altogether, the standing dissipative shocks in viscous flows may occur only if α black hole candidates such as GX399-4, MAXI J1659-152 and MAXI J1836-194 and find that required α are indeed well within our prescribed limit.

  7. The origin of compact galaxies with anomalously high black hole masses

    CERN Document Server

    Barber, Christopher; Bower, Richard G; Crain, Robert A; Schaller, Matthieu; Theuns, Tom

    2016-01-01

    Observations of local galaxies harbouring supermassive black holes (BH) of anomalously high mass, M_BH, relative to their stellar mass, M_star, appear to be at odds with simple models of the co-evolution between galaxies and their central BHs. We study the origin of such outliers in a LCDM context using the EAGLE cosmological, hydrodynamical simulation. We find 15 "M_BH(M_star)-outlier" galaxies, defined as having M_BH more than 1.5 dex above the median M_BH(M_star) relation in the simulation, M_{BH,med}. All M_BH(M_star)-outliers are satellite galaxies, typically with M_star ~ 10^10 M_sun and M_BH ~ 10^8 M_sun. They have all become outliers primarily due to tidal stripping of their outer stellar component acting over several Gyr, with a secondary effect of rapid BH growth at high-z causing some to lie approximately 1 dex above the z=0 relation prior to stripping. The same mechanisms also cause the M_BH(M_star)-outlier satellites to be amongst the most compact galaxies in the simulation, making them ideal can...

  8. Lee-Wick Black Holes

    CERN Document Server

    Bambi, Cosimo; Wang, Yixu

    2016-01-01

    We derive and study an approximate static vacuum solution generated by a point-like source in a higher derivative gravitational theory with a pair of complex conjugate ghosts. The gravitational theory is local and characterized by a high derivative operator compatible with Lee-Wick unitarity. In particular, the tree-level two-point function only shows a pair of complex conjugate poles besides the massless spin two graviton. We show that singularity-free black holes exist when the mass of the source $M$ exceeds a critical value $M_{\\rm crit}$. For $M > M_{\\rm crit}$ the spacetime structure is characterized by an outer event horizon and an inner Cauchy horizon, while for $M = M_{\\rm crit}$ we have an extremal black hole with vanishing Hawking temperature. The evaporation process leads to a remnant that approaches the zero-temperature extremal black hole state in an infinite amount of time.

  9. Lee-Wick black holes

    Science.gov (United States)

    Bambi, Cosimo; Modesto, Leonardo; Wang, Yixu

    2017-01-01

    We derive and study an approximate static vacuum solution generated by a point-like source in a higher derivative gravitational theory with a pair of complex conjugate ghosts. The gravitational theory is local and characterized by a high derivative operator compatible with Lee-Wick unitarity. In particular, the tree-level two-point function only shows a pair of complex conjugate poles besides the massless spin two graviton. We show that singularity-free black holes exist when the mass of the source M exceeds a critical value Mcrit. For M >Mcrit the spacetime structure is characterized by an outer event horizon and an inner Cauchy horizon, while for M =Mcrit we have an extremal black hole with vanishing Hawking temperature. The evaporation process leads to a remnant that approaches the zero-temperature extremal black hole state in an infinite amount of time.

  10. Jet precession in neutrino-cooled disks for gamma-ray bursts: The effects of the mass and spin of a black hole

    Institute of Scientific and Technical Information of China (English)

    Liu Tong; Xue Li

    2012-01-01

    We present a model of jet precession driven by a neutrino-cooled disk around a spinning black hole to explain the quasi-periodic features observed in some gamma-ray burst light curves.The different orientations of the rotational axes between the outer part of a neutrino-cooled disk and a black hole result in precessions of the central black hole and the inner part of the disk.Hence,the jet arising from the neutrino annihilation above the inner disk is driven to precession.We find that the period of precession is positively correlated with the mass as well as the spin of a black hole.

  11. Superradiance by mini black holes with mirror

    OpenAIRE

    Lee, Jong-Phil

    2011-01-01

    The superradiant scattering of massive scalar particles by a rotating mini black hole is investigated. Imposing the mirror boundary condition, the system becomes the so called black-hole bomb where the rotation energy of the black hole is transferred to the scattered particle exponentially with time. Bulk emissions as well as brane emissions are considered altogether. It is found that the largest effects are expected for the brane emission of lower angular modes with lighter mass and larger a...

  12. Spectroscopic analysis of stellar mass black-hole mergers in our local universe with ground-based gravitational wave detectors

    CERN Document Server

    Bhagwat, Swetha; Ballmer, Stefan W

    2016-01-01

    Motivated by the recent discoveries of binary black-hole mergers by the Advanced Laser Interferometer Gravitational-wave Observatory (Advanced LIGO), we investigate the prospects of ground-based detectors to perform a spectroscopic analysis of signals emitted during the ringdown of the final Kerr black-hole formed by a stellar mass binary black-hole merger. Although it is unlikely that Advanced LIGO can measure multiple modes of the ringdown, assuming an optimistic rate of 240 Gpc$^{-3}$yr$^{-1}$, upgrades to the existing LIGO detectors could measure multiple ringdown modes in $\\sim$6 detections per year. New ground-based facilities such as Einstein Telescope or Cosmic Explorer could measure multiple ringdown modes in over 300 events per year. We perform Monte-Carlo injections of $10^{6}$ binary black-hole mergers in a search volume defined by a sphere of radius 1500 Mpc centered at the detector, for various proposed ground-based detector models. We assume a uniform random distribution in component masses of ...

  13. Limits on intermediate-mass black holes in six Galactic globular clusters with integral-field spectroscopy

    CERN Document Server

    Lützgendorf, Nora; Gebhardt, Karl; Baumgardt, Holger; Noyola, Eva; de Zeeuw, P Tim; Neumayer, Nadine; Jalali, Behrang; Feldmeier, Anja

    2012-01-01

    The formation of supermassive black holes at high redshift still remains a puzzle to astronomers. Their growth becomes reasonable only when starting from a massive seed black hole with mass of the order of 10^2 - 10^5 M_SUN. Intermediate-mass black holes (IMBHs) are therefore an important field of research. Especially the possibility of finding them in the centers of globular clusters has recently drawn attention. The search for IMBHs in the centers of globular clusters could therefore shed light on the process of black-hole formation and cluster evolution. We are investigating six galactic globular clusters for the presence of an IMBH at their centers. Based on their kinematic and photometric properties, we selected the globular clusters NGC 1851, NGC 1904 (M79), NGC 5694, NGC 5824, NGC 6093 (M80) and NGC 6266 (M62). We use integral field spectroscopy in order to obtain the central velocity-dispersion profile of each cluster. We compute the cluster photometric center and the surface brightness profile using ...

  14. The Supermassive Black Hole Mass - Spheroid Stellar Mass Relation for S\\'ersic and Core-S\\'ersic Galaxies

    CERN Document Server

    Scott, Nicholas; Schombert, James

    2013-01-01

    We have examined the relationship between supermassive black hole mass (M_BH) and the stellar mass of the host spheroid (M_sph,*) for a sample of 75 nearby galaxies. To derive the spheroid stellar masses we used improved 2MASS K_s-band photometry from the ARCHANGEL photometry pipeline. Dividing our sample into core-S\\'ersic and S\\'ersic galaxies, we find that they are described by very different M_BH-M_sph,* relations. For core-S\\'ersic galaxies - which are typically massive and luminous, with M_BH \\gtrsim 2x10^8 M_solar - we find M_BH \\propto M_sph,*^(0.97 \\pm 0.14), consistent with other literature relations. However, for the S\\'ersic galaxies - with typically lower masses, M_sph,* \\lesssim 3x10^10 M_solar - we find M_BH \\propto M_sph,*^(2.22 \\pm 0.58), a dramatically steeper slope that differs by more than 2 standard deviations. This relation confirms that, for S\\'ersic galaxies, M_BH is not a constant fraction of M_sph,*. S\\'ersic galaxies can grow via the accretion of gas which fuels both star formation ...

  15. On the non-evolution of the dependence of black hole masses on bolometric luminosities for QSOs

    Institute of Scientific and Technical Information of China (English)

    Martín López-Corredoira; Carlos M. Gutiérrez

    2012-01-01

    There are extremely luminous quasi stellar objects (QSOs) at high redshift which are absent at low redshift.The lower luminosities at low redshifts can be understood as the external manifestation of either a lower Eddington ratio or a lower mass.To distinguish between both effects,we determine the possible dependence of masses and Eddington ratios of QSOs with a fixed luminosity as a function of redshifts; this avoids the Malmquist bias or any other selection effect.For the masses and Eddington ratios derived for a sample of QSOs in the Sloan Digital Sky Survey,we model their evolution by a double linear fit separating the dependence on redshifts and luminosities.The validity of the fits and possible systematic effects were tested by the use of different estimators of masses or bolometric luminosities,and possible intergalactic extinction effects.The results do not show any significant evolution of black hole masses or Eddington ratios for equal luminosity QSOs.The black hole mass only depends on the bolometric luminosity without significant dependence on the redshift as (MBH/109M☉)≈ 3.4 (Lbol/(1047ergs-1)0.65on average for z ≤ 5.This must not be confused with the possible evolution in the formation of black holes in QSOs.The variations of the environment might influence the formation of the black holes but not their subsequent accretion.It also leaves a question to be solved:Why are there not QSOs with very high mass at low redshift? A brief discussion of the possible reasons for this is tentatively pointed out.

  16. Black Hole Induced Ejections

    CERN Document Server

    Pelletier, G

    2004-01-01

    Black Holes generate a particular kind of environments dominated by an accretion flow which concentrates a magnetic field. The interplay of gravity and magnetism creates this paradoxical situation where relativistic ejection is allowed and consequently high energy phenomena take place. Therefore Black Holes, which are very likely at the origin of powerfull astrophysical phenomena such as AGNs, micro- quasars and GRBs where relativistic ejections are observed, are at the heart of high energy astrophysics. The combination of General Relativity and Magneto-HydroDynamics (MHD) makes theory difficult; however great pionneers opened beautiful tracks in the seventies and left important problems to be solved for the next decades. These lectures will present the status of these issues. They have a tutorial aspect together with critical review aspect and contain also some new issues. Most of these lectures has been presented at the "School on Black Hole in the Universe" at Cargese, in May 2003.

  17. Turbulent black holes.

    Science.gov (United States)

    Yang, Huan; Zimmerman, Aaron; Lehner, Luis

    2015-02-27

    We demonstrate that rapidly spinning black holes can display a new type of nonlinear parametric instability-which is triggered above a certain perturbation amplitude threshold-akin to the onset of turbulence, with possibly observable consequences. This instability transfers from higher temporal and azimuthal spatial frequencies to lower frequencies-a phenomenon reminiscent of the inverse cascade displayed by (2+1)-dimensional fluids. Our finding provides evidence for the onset of transitory turbulence in astrophysical black holes and predicts observable signatures in black hole binaries with high spins. Furthermore, it gives a gravitational description of this behavior which, through the fluid-gravity duality, can potentially shed new light on the remarkable phenomena of turbulence in fluids.

  18. Merging Black Holes

    Science.gov (United States)

    Centrella, Joan

    2012-01-01

    The final merger of two black holes is expected to be the strongest source of gravitational waves for both ground-based detectors such as LIGO and VIRGO, as well as future. space-based detectors. Since the merger takes place in the regime of strong dynamical gravity, computing the resulting gravitational waveforms requires solving the full Einstein equations of general relativity on a computer. For many years, numerical codes designed to simulate black hole mergers were plagued by a host of instabilities. However, recent breakthroughs have conquered these instabilities and opened up this field dramatically. This talk will focus on.the resulting 'gold rush' of new results that is revealing the dynamics and waveforms of binary black hole mergers, and their applications in gravitational wave detection, testing general relativity, and astrophysics

  19. Black hole entropy quantization

    CERN Document Server

    Corichi, A; Fernandez-Borja, E; Corichi, Alejandro; Diaz-Polo, Jacobo; Fernandez-Borja, Enrique

    2006-01-01

    Ever since the pioneer works of Bekenstein and Hawking, black hole entropy has been known to have a quantum origin. Furthermore, it has long been argued by Bekenstein that entropy should be quantized in discrete (equidistant) steps given its identification with horizon area in (semi-)classical general relativity and the properties of area as an adiabatic invariant. This lead to the suggestion that black hole area should also be quantized in equidistant steps to account for the discrete black hole entropy. Here we shall show that loop quantum gravity, in which area is not quantized in equidistant steps can nevertheless be consistent with Bekenstein's equidistant entropy proposal in a subtle way. For that we perform a detailed analysis of the number of microstates compatible with a given area and show that an observed oscillatory behavior in the entropy-area relation, when properly interpreted yields an entropy that has discrete, equidistant values that are consistent with the Bekenstein framework.

  20. Black hole gravitohydromagnetics

    CERN Document Server

    Punsly, Brian

    2008-01-01

    Black hole gravitohydromagnetics (GHM) is developed from the rudiments to the frontiers of research in this book. GHM describes plasma interactions that combine the effects of gravity and a strong magnetic field, in the vicinity (ergosphere) of a rapidly rotating black hole. This topic was created in response to the astrophysical quest to understand the central engines of radio loud extragalactic radio sources. The theory describes a "torsional tug of war" between rotating ergospheric plasma and the distant asymptotic plasma that extracts the rotational inertia of the black hole. The recoil from the struggle between electromagnetic and gravitational forces near the event horizon is manifested as a powerful pair of magnetized particle beams (jets) that are ejected at nearly the speed of light. These bipolar jets feed large-scale magnetized plasmoids on scales as large as millions of light years (the radio lobes of extragalactic radio sources). This interaction can initiate jets that transport energy fluxes exc...

  1. Problem of mathematical deduction of the existence of black holes

    Directory of Open Access Journals (Sweden)

    Yuan-Shun Chin

    1990-01-01

    Full Text Available The mathematical proof of existence of Black Hole is based on the assumption of mass being independent of speed. Considering the effect of special relativity of the dependence of mass with speed there is no Black hole.

  2. The surface density profile of NGC 6388 : a good candidate for harboring an intermediate-mass black hole

    CERN Document Server

    Lanzoni, B; Ferraro, F R; Miocchi, P; Valenti, E; Rood, R T

    2007-01-01

    We have used a combination of high resolution (HST ACS-HRC, ACS-WFC, and WFPC2) and wide-field (ESO-WFI) observations of the galactic globular cluster NGC 6388 to derive its center of gravity, projected density profile, and central surface brightness profile. While the overall projected profiles are well fit by a King model with intermediate concentration (c=1.8) and sizable core radius (rc=7"), a significant power law (with slope \\alpha=-0.2) deviation from a flat core behavior has been detected within the inner 1 arcsecond. These properties suggest the presence of a central intermediate mass black hole. The observed profiles are well reproduced by a multi-mass isotropic, spherical model including a black hole with a mass of ~5.7x10^3 Msol.

  3. Life Inside Black Holes

    Science.gov (United States)

    Dokuchaev, Vyacheslav

    2013-11-01

    It is considered the test planet and photon orbits of the third kind inside the black hole (BH), which are stable, periodic and neither come out the BH nor terminate at the central singularity. Interiors of the supermassive BHs may be inhabited by advanced civilizations living on the planets with the third kind orbits. In principle, one can get information from the interiors of BHs by observing their white hole counterparts.

  4. The Black Hole Mass-Bulge Luminosity Relationship for Reverberation-Mapped AGNs in the Near-IR

    Science.gov (United States)

    Nicholas, Emily; Bentz, M. C.

    2014-01-01

    We present preliminary results for a near-IR M-L scaling relationship for active galaxies in the reverberation sample. We are particularly interested in the effect of host-galaxy morphology on the M-L scaling relationship. In order to study evolution over cosmic time we must employ scaling relations, which are calibrated to the direct methods of black hole mass measurement and rely on correlations between host galaxy properties and black hole masses. However, it remains uncertain which scaling relation most reliably predicts black hole masses based on host galaxy observables. Recent studies of the M- relationship have uncovered a possible offset in the relationship due to the presence of a pseudobulge or bar in the host galaxy. This offset would adversely affect one's ability to use the M-relationship as a way to estimate black hole masses efficiently because it would require the detailed morphology of the galaxy to be known a priori. Preliminary results based on optical HST data suggest that the M-L relation for active galaxies with reverberation-based black hole masses is not plagued by the same offsets. However, due to dust and on-going star formation, the optical data yield an M-L relationship with a slightly higher scatter than the M- relation. We have carried out near-IR imaging with the WIYN High-Resolution Infrared Camera (WHIRC) on the WIYN telescope to minimize the effects of dust and star formation in order to test whether the M-L relationship is a more accurate predictor of black hole masses and a potentially more fundamental relationship. The imaging campaign has been completed, and we are currently in the process of carefully modeling the galaxy surface brightness features so that we can accurately remove the contribution from the point spread function of the active nucleus. We present our preliminary results here, and we expect that the final results will prove to be quite useful in conjunction with future large imaging surveys, such as LSST, which

  5. Horndeski black hole geodesics

    CERN Document Server

    Tretyakova, D A

    2016-01-01

    We examine geodesics for the scalar-tensor black holes in the Horndeski-Galileon framework. Our analysis shows that first kind relativistic orbits may not be present within some model parameters range. This is a highly pathological behavior contradicting to the black hole accretion and Solar System observations. We also present a new (although very similar to those previously known) solution, which contains the orbits we expect from a compact object, admits regular scalar field at the horizon and and can fit into the known stability criteria.

  6. Are Black Holes Springy?

    CERN Document Server

    Good, Michael R R

    2014-01-01

    A $(3+1)$-dimensional asymptotically flat Kerr black hole angular speed $\\Omega_+$ can be used to define an effective spring constant, $k=m\\Omega_+^2$. Its maximum value is the Schwarzschild surface gravity, $k = \\kappa $, which rapidly weakens as the black hole spins down and the temperature increases. The Hawking temperature is expressed in terms of the spring constant: $2\\pi T = \\kappa - k$. Hooke's law, in the extremal limit, provides the force $F = 1/4$, which is consistent with the conjecture of maximum force in general relativity.

  7. Acoustic black holes

    CERN Document Server

    Visser, M

    1999-01-01

    Acoustic propagation in a moving fluid provides a conceptually clean and powerful analogy for understanding black hole physics. As a teaching tool, the analogy is useful for introducing students to both General Relativity and fluid mechanics. As a research tool, the analogy helps clarify what aspects of the physics are kinematics and what aspects are dynamics. In particular, Hawking radiation is a purely kinematical effect, whereas black hole entropy is intrinsically dynamical. Finally, I discuss the fact that with present technology acoustic Hawking radiation is almost experimentally testable.

  8. Superfluid Black Holes

    CERN Document Server

    Hennigar, Robie A; Tjoa, Erickson

    2016-01-01

    We present what we believe is the first example of a "$\\lambda$-line" phase transition in black hole thermodynamics. This is a line of (continuous) second order phase transitions which in the case of liquid $^4$He marks the onset of superfluidity. The phase transition occurs for a class of asymptotically AdS hairy black holes in Lovelock gravity where a real scalar field is conformally coupled to gravity. We discuss the origin of this phase transition and outline the circumstances under which it (or generalizations of it) could occur.

  9. Superfluid Black Holes.

    Science.gov (United States)

    Hennigar, Robie A; Mann, Robert B; Tjoa, Erickson

    2017-01-13

    We present what we believe is the first example of a "λ-line" phase transition in black hole thermodynamics. This is a line of (continuous) second order phase transitions which in the case of liquid ^{4}He marks the onset of superfluidity. The phase transition occurs for a class of asymptotically anti-de Sitter hairy black holes in Lovelock gravity where a real scalar field is conformally coupled to gravity. We discuss the origin of this phase transition and outline the circumstances under which it (or generalizations of it) could occur.

  10. Modeling black hole evaporation

    CERN Document Server

    Fabbri, Alessandro

    2005-01-01

    The scope of this book is two-fold: the first part gives a fully detailed and pedagogical presentation of the Hawking effect and its physical implications, and the second discusses the backreaction problem, especially in connection with exactly solvable semiclassical models that describe analytically the black hole evaporation process. The book aims to establish a link between the general relativistic viewpoint on black hole evaporation and the new CFT-type approaches to the subject. The detailed discussion on backreaction effects is also extremely valuable.

  11. MEASURING THE LUMINOSITY AND VIRIAL BLACK HOLE MASS DEPENDENCE OF QUASAR–GALAXY CLUSTERING AT z ∼ 0.8

    Energy Technology Data Exchange (ETDEWEB)

    Krolewski, Alex G.; Eisenstein, Daniel J., E-mail: akrolewski@college.harvard.edu [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

    2015-04-10

    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 the Wide-field Infrared Survey Explorer (WISE) about z ∼ 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 ∼ 0.8 quasars at 0.2–6.4 h{sup −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 ± 0.06 (1 σ error). We also fail to find a significant relationship between clustering amplitude and black hole mass, although our dynamic range in true mass is suppressed due to the large uncertainties in virial black hole mass estimates. Our results indicate that a small range in host dark matter halo mass maps to a large range in quasar luminosity.

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

    CERN Document Server

    Lake, Matthew J

    2015-01-01

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

  13. A low upper mass limit for the central black hole in the late-type galaxy NGC 4414

    Science.gov (United States)

    Thater, S.; Krajnović, D.; Bourne, M. A.; Cappellari, M.; de Zeeuw, T.; Emsellem, E.; Magorrian, J.; McDermid, R. M.; Sarzi, M.; van de Ven, G.

    2017-01-01

    We present our mass estimate of the central black hole in the isolated spiral galaxy NGC 4414. Using natural guide star adaptive optics assisted observations with the Gemini Near-Infrared Integral Field Spectrometer (NIFS) and the natural seeing Gemini Multi-Object Spectrographs-North (GMOS), we derived two-dimensional stellar kinematic maps of NGC 4414 covering the central 1.5 arcsec and 10 arcsec, respectively, at a NIFS spatial resolution of 0.13 arcsec. The kinematic maps reveal a regular rotation pattern and a central velocity dispersion dip down to around 105 km s-1. We constructed dynamical models using two different methods: Jeans anisotropic dynamical modeling and axisymmetric Schwarzschild modeling. Both modeling methods give consistent results, but we cannot constrain the lower mass limit and only measure an upper limit for the black hole mass of MBH = 1.56 × 106M⊙ (at 3σ level) which is at least 1σ below the recent MBH-σe relations. Further tests with dark matter, mass-to-light ratio variation and different light models confirm that our results are not dominated by uncertainties. The derived upper limit mass is not only below the MBH-σe relation, but is also five times lower than the lower limit black hole mass anticipated from the resolution limit of the sphere of influence. This proves that via high quality integral field data we are now able to push black hole measurements down to at least five times less than the resolution limit. The reduced data cubes (FITS files) are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/597/A18

  14. Black Hole Blows Big Bubble

    Science.gov (United States)

    2010-07-01

    Combining observations made with ESO's Very Large Telescope and NASA's Chandra X-ray telescope, astronomers have uncovered the most powerful pair of jets ever seen from a stellar black hole. This object, also known as a microquasar, blows a huge bubble of hot gas, 1000 light-years across, twice as large and tens of times more powerful than other known microquasars. The discovery is reported this week in the journal Nature. "We have been astonished by how much energy is injected into the gas by the black hole," says lead author Manfred Pakull. "This black hole is just a few solar masses, but is a real miniature version of the most powerful quasars and radio galaxies, which contain black holes with masses of a few million times that of the Sun." Black holes are known to release a prodigious amount of energy when they swallow matter. It was thought that most of the energy came out in the form of radiation, predominantly X-rays. However, the new findings show that some black holes can release at least as much energy, and perhaps much more, in the form of collimated jets of fast moving particles. The fast jets slam into the surrounding interstellar gas, heating it and triggering an expansion. The inflating bubble contains a mixture of hot gas and ultra-fast particles at different temperatures. Observations in several energy bands (optical, radio, X-rays) help astronomers calculate the total rate at which the black hole is heating its surroundings. The astronomers could observe the spots where the jets smash into the interstellar gas located around the black hole, and reveal that the bubble of hot gas is inflating at a speed of almost one million kilometres per hour. "The length of the jets in NGC 7793 is amazing, compared to the size of the black hole from which they are launched," says co-author Robert Soria [1]. "If the black hole were shrunk to the size of a soccer ball, each jet would extend from the Earth to beyond the orbit of Pluto." This research will help

  15. Is There a Maximum Mass for Black Holes in Galactic Nuclei?

    Science.gov (United States)

    Inayoshi, Kohei; Haiman, Zoltán

    2016-09-01

    The largest observed supermassive black holes (SMBHs) have a mass of {M}{{BH}}≃ {10}10 {\\text{}}{M}⊙ , nearly independent of redshift, from the local (z≃ 0) to the early (z\\gt 6) universe. We suggest that the growth of SMBHs above a few × {10}10 {\\text{}}{M}⊙ is prevented by small-scale accretion physics, independent of the properties of their host galaxies or of cosmology. Growing more massive BHs requires a gas supply rate from galactic scales onto a nuclear region as high as ≳ {10}3 {M}⊙ {{{yr}}}-1. At such a high accretion rate, most of the gas converts to stars at large radii (˜10-100 pc), well before reaching the BH. We adopt a simple model for a star-forming accretion disk and find that the accretion rate in the subparsec nuclear region is reduced to the smaller value of at most a few × {M}⊙ {{{yr}}}-1. This prevents SMBHs from growing above ≃ {10}11 {\\text{}}{M}⊙ in the age of the universe. Furthermore, once an SMBH reaches a sufficiently high mass, this rate falls below the critical value at which the accretion flow becomes advection dominated. Once this transition occurs, BH feeding can be suppressed by strong outflows and jets from hot gas near the BH. We find that the maximum SMBH mass, given by this transition, is between {M}{{BH,max}}≃ (1{--}6)× {10}10 {\\text{}}{M}⊙ , depending primarily on the efficiency of angular momentum transfer inside the galactic disk, and not on other properties of the host galaxy.

  16. On the theoretical framework of magnetized outflows from stellar-mass black holes and related observations

    Science.gov (United States)

    Christodoulou, D. M.; Contopoulos, I.; Kazanas, D.; Steiner, J. F.; Papadopoulos, D. B.; Laycock, S. G. T.

    2016-09-01

    The spins of stellar-mass black holes (BHs) and the power outputs of their jets are measurable quantities. Unfortunately, the currently employed methods do not agree and the results are controversial. Two major issues concern the measurements of BH spin and beam (jet) power. The former issue can be resolved by future observations. But the latter issue can be resolved now, if we pay attention to what is expected from theoretical considerations. The question of whether a correlation has been found between the power outputs of few objects and the spins of their BHs is moot because BH beam power does not scale with the square of the spin of the BH. We show that the theoretical BH beam power is a strongly non-linear function of spin that cannot be approximated by a quadratic relation, as is generally stated when the influence of the magnetic field is not accounted for in the Blandford & Znajek model. The BH beam power of ballistic jets should scale a lot more steeply with BH spin irrespective of the magnetic field assumed to thread the horizon and the spin range considered. This behaviour may already be visible in the analyses of radio observations by Narayan & McClintock and Russell et al. In agreement with previous studies, we also find that the power output that originates in the inner regions of the surrounding accretion discs is higher than that from the BHs and it cannot be ignored in investigations of continuous compact jets from these systems.

  17. Spin-orbit precession for eccentric black hole binaries at first order in the mass ratio

    CERN Document Server

    Akcay, Sarp; Dolan, Sam

    2016-01-01

    We consider spin-orbit ("geodetic") precession for a compact binary in strong-field gravity. Specifically, we compute $\\psi$, the ratio of the accumulated spin-precession and orbital angles over one radial period, for a spinning compact body orbiting a non-rotating black hole. We show that $\\psi$ can be computed for eccentric orbits in both the gravitational self-force and post-Newtonian frameworks, and that the results appear to be consistent. We present a post-Newtonian expansion for $\\psi$ at next-to-next-to-leading order, and a Lorenz-gauge gravitational self-force calculation for $\\psi$ at first order in the mass ratio. The latter provides new numerical data in the strong-field regime to inform the Effective One-Body model of the gravitational two-body problem. We conclude that $\\psi$ complements the Detweiler redshift $z$ as a key invariant quantity characterizing eccentric orbits in the gravitational two-body problem.

  18. On the Theoretical Framework of Magnetized Outflows from Stellar-Mass Black Holes and Related Observations

    CERN Document Server

    Christodoulou, D M; Kazanas, D; Steiner, J F; Papadopoulos, D B; Laycock, S G T

    2016-01-01

    The spins of stellar-mass black holes (BHs) and the power outputs of their jets are measurable quantities. Unfortunately, the currently employed methods do not agree and the results are controversial. Two major issues concern the measurements of BH spin and beam (jet) power. The former issue can be resolved by future observations. But the latter issue can be resolved now, if we pay attention to what is expected from theoretical considerations. The question of whether a correlation has been found between the power outputs of few objects and the spins of their BHs is moot because BH beam power does not scale with the square of the spin of the BH. We show that the theoretical BH beam power is a strongly nonlinear function of spin that cannot be approximated by a quadratic relation, as is generally stated when the influence of the magnetic field is not accounted for in the \\cite{bla77} model. The BH beam power of ballistic jets should scale a lot more steeply with BH spin irrespective of the magnetic field assume...

  19. On the Virialization of Disk Winds: Implications for the Black Hole Mass Estimates in AGN

    CERN Document Server

    Kashi, Amit; Nagamine, Kentaro; Greene, Jenny; Barth, Aaron J

    2013-01-01

    [abbreviated] Estimating the mass of a supermassive black hole (SMBH) in an active galactic nucleus (AGN) usually relies on the assumption that the broad line region (BLR) is virialized. However, this assumption seems invalid in BLR models that consists of an accretion disk and its wind. The disk is likely Keplerian and therefore virialized. However, the wind material must, beyond a certain point, be dominated by an outward force that is stronger than gravity. Here, we analyze hydrodynamic simulations of four different disk winds: an isothermal wind, a thermal wind from an X-ray heated disk, and two line-driven winds, one with and the other without X-ray heating and cooling. For each model, we check whether gravity governs the flow properties, by computing and analyzing the volume-integrated quantities that appear in the virial theorem: internal, kinetic, and gravitational energies, We find that in the first two models, the winds are non-virialized whereas the two line-driven disk winds are virialized up to a...

  20. Adaptive Optics Assisted 3D spectroscopy observations for black hole mass measurements

    CERN Document Server

    Pastorini, G

    2006-01-01

    The very high spatial resolution provided by Adaptive Optics assisted spectroscopic observations at 8m-class telescopes (e.g. with SINFONI at the VLT) will allow to greatly increase the number of direct black hole (BH) mass measurements which is currently very small. This is a fundamental step to investigate the tight link between galaxy evolution and BH growth, revealed by the existing scaling relations between $M_{BH}$ and galaxy structural parameters. I present preliminary results from SINFONI K-band spectroscopic observations of a sample of 5 objects with $M_{BH}$ measurements obtained with the Reverberation Mapping (RM) technique. This technique is the starting point to derive the so-called virial $M_{BH}$ estimates, currently the only way to measure $M_{BH}$ at high redshift. Our goal is to assess the reliability of RM by measuring $M_{BH}$ with both gas and stellar kinematical methods and to investigate whether active galaxies follow the same $M_{BH}$-galaxy correlations as normal ones.