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Fender12 BHB.Pdf Stellar-Mass Black Holes and Ultraluminous X-ray Sources Rob Fender and Tomaso Belloni Science 337, 540 (2012); DOI: 10.1126/science.1221790 This copy is for your personal, non-commercial use only. If you wish to distribute this article to others, you can order high-quality copies for your colleagues, clients, or customers by clicking here. Permission to republish or repurpose articles or portions of articles can be obtained by following the guidelines here. The following resources related to this article are available online at www.sciencemag.org (this information is current as of March 28, 2013 ): Updated information and services, including high-resolution figures, can be found in the online on March 28, 2013 version of this article at: http://www.sciencemag.org/content/337/6094/540.full.html Supporting Online Material can be found at: http://www.sciencemag.org/content/suppl/2012/08/01/337.6094.540.DC1.html A list of selected additional articles on the Science Web sites related to this article can be found at: http://www.sciencemag.org/content/337/6094/540.full.html#related This article cites 37 articles, 6 of which can be accessed free: www.sciencemag.org http://www.sciencemag.org/content/337/6094/540.full.html#ref-list-1 This article has been cited by 1 articles hosted by HighWire Press; see: http://www.sciencemag.org/content/337/6094/540.full.html#related-urls This article appears in the following subject collections: Astronomy http://www.sciencemag.org/cgi/collection/astronomy Downloaded from Science (print ISSN 0036-8075; online ISSN 1095-9203) is published weekly, except the last week in December, by the American Association for the Advancement of Science, 1200 New York Avenue NW, Washington, DC 20005. Copyright 2012 by the American Association for the Advancement of Science; all rights reserved. The title Science is a registered trademark of AAAS. Black Holes Einstein equations to describe the black hole, one dissipative behavior in model systems with a de- transition amplitude <f |H|i> is the complex conjugate can get striking insight about a quantum almost- gree of detail that is not usually possible. In a of the transition amplitude <i|H|f > in the opposite direction. ideal fluid (10). This has become an important sense, this brings our story full circle. The story 2. The precise time-reversal symmetry of nature also technique in modeling heavy ion collisions. began nearly 40 years ago with the initial insight includes reflection symmetry and charge conjugation. Condensed matter physics is described in prin- that the irreversibility of black hole physics is anal- 3. J. Bekenstein, Phys.Rev.DPart.Fields7, 2333 ciple by the Schrödinger equation of electrons and ogous to the irreversibility described by the sec- (1973). 4. S. W. Hawking, Nature 248, 30 (1974). nuclei, but for most systems, a full understanding ond law of thermodynamics. In general, to reconcile 5.K.S.Thorne,D.A.MacDonald,R.H.Price,Eds., based on the Schrödinger equation is way out of this irreversibility with the reversible nature of the Black Holes: The Membrane Paradigm (Yale Univ. reach. Nowadays, there is great interest in under- fundamental equations is tricky, and explicit cal- Press, New Haven, CT 1986). standing quantum critical behavior in quasi–two- culations are not easy to come by. The link be- 6. A. Strominger, C. Vafa, Phys. Lett. B 379, 99 (1996). dimensional systems such as high temperature tween ordinary physics and black hole physics that 7. S. S. Gubser, I. R. Klebanov, A. W. Peet, Phys. Rev. D Part. Fields 54, 3915 (1996). superconductors. These systems are studied by a is given by gauge-gravity duality has given physi- 8. J. M. Maldacena, Adv. Theor. Math. Phys. 2, 231 (1998). wide variety of methods, and no one approach is cists a powerful way to do precisely this. This gives 9. M. J. Duff, R. R. Khuri, J.-X. Lu, Phys. Rep. 259, 213 likely to be a panacea. Still, it has turned out to be us confidence that we are on the right track in (1995). very interesting to study two-dimensional quantum understanding quantum black holes, and it also 10. P. K. Kovtun, D. T. Son, A. O. Starinets, Phys. Rev. Lett. 94, 111601 (2005). critical systems by mapping them to the horizon of exhibits the unity of physics in a most pleasing way. 11. S. Sachdev, Annu. Rev. Cond. Matt. Phys. 3, 9 (2012). a black hole (11). With this approach, one can per- form calculations that are usually out of reach. Acknowledgments: This research was supported in part References and Notes by NSF grant PHY-096944. Among other things, this method has been 1. The precise mathematical argument uses the fact that used to analyze the crossover from quantum to the Hamiltonian operator H is hermitian, so that the 10.1126/science.1221693 REVIEW both were moderately certain it was a black hole, Hawking wanted an insurance policy). In 1990, Hawking conceded the bet, accepting that the on March 28, 2013 Stellar-Mass Black Holes source contained a black hole. Since then, astron- omers have discovered many hundreds of x-ray and Ultraluminous X-ray Sources binaries within the Milky Way and beyond, several tens of which are good candidate BHXRBs (4). Rob Fender1* and Tomaso Belloni2 Over the past decade, repeating empirical pat- terns connecting the x-ray, radio, and infrared emis- We review the likely population, observational properties, and broad implications of stellar-mass sion from these objects have been found and used black holes and ultraluminous x-ray sources. We focus on the clear empirical rules connecting to connect these observations to physical compo- accretion and outflow that have been established for stellar-mass black holes in binary systems in nents of the accretion flow (Fig. 1). It is likely that www.sciencemag.org the past decade and a half. These patterns of behavior are probably the keys that will allow us some of these empirical patterns of behavior also 5 9 to understand black hole feedback on the largest scales over cosmological time scales. apply to accreting supermassive (10 to 10 M⊙) black holes in the centers of some galaxies, and tellar-mass black holes are the end points galaxy, under the assumption that all stars of ini- that from studying BHXRBs on humanly accessi- of the evolution of the most massive stars. tial mass >10 times that of the Sun met this fate. ble time scales, we may be learning about the forces SThecollapseofanironcoreof>3solar The strongest evidence for the existence of this that shaped the growth of galaxies over the life- masses (M⊙) cannot be stopped by either electron population of stellar-mass black holes comes from time of the universe. Between the stellar-mass black or neutron degeneracy pressure (which would other- observations of x-ray binary systems (XRBs). In holes and the supermassive, there could be a popu- Downloaded from wise result in a white dwarf, or neutron star, respec- XRBs, matter is accreted (gravitationally captured lation of intermediate-mass black holes (IMBHs), 2 5 tively). Within the framework of classical general into/onto the accretor), releasing large amounts of with masses in the range of 10 to 10 M⊙.These relativity (GR), the core collapses to a singularity gravitational potential energy in the process. The may be related to the ultra-luminous x-ray sources that is cloaked in an event horizon before it can be efficiency of this process in releasing the gravita- (ULXs), very luminous x-ray sources that have been viewed. Like a giant elementary particle, the result- tional potential energy is determined by the ratio observed in external galaxies. However, the problem ing black hole is then entirely described by three of mass to radius of the accretor. For neutron of the nature of these sources is still unsettled, and parameters: mass, spin, and charge (1). Because stars, more than 10% of the rest mass energy can alternative options involving stellar-mass black galaxies are old—the Milky Way is at least 13 bil- be released—a process more efficient at energy re- holes are still open. lion years old—and the most massive stars evolve lease than nuclear fusion. For black holes, the ef- quickly (within millions of years or less), there ficiency can be even higher (3),butthepresenceof Black Hole X-ray Binaries are likely to be a large number of such stellar-mass an event horizon—from within which no signals can There are several different approaches to clas- black holes in our galaxy alone. Shapiro and ever be observed in the outside universe—means sifying BHXRBs and their behavior, each of Teukolsky (2) calculated that there were likely to that this accretion power may be lost. which can lead to different physical insights. One be as many as 108 stellar-mass black holes in our In some of these systems, dynamical mea- important approach is to look at the orbital pa- surements of the orbit indicate massive (>3 M⊙) rameters, and the most important of these is the accretors that, independently, show no evidence mass of the donor star because it relates to the 1 Physics and Astronomy, University of Southampton, Southampton for any emission from a solid surface. The first age of the binary. High-mass x-ray binaries have SO17 1BJ, UK. 2Istituto Nazionale di Astrofisica–Osservatorio Astronomico di Brera, Via Emilio Bianchi 46, I-23807 Merate such candidate black hole x-ray binary (BHXRB) OB-type (5) massive donors and are young sys- (LC), Italy. system detected was Cygnus X-1, which led to a tems, typically with ages less than a million years *To whom correspondence should be addressed.
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