OBSERVATIONAL SIGNATURES OF BINARY SUPERMASSIVE BLACK HOLES
OBSERVATIONAL SIGNATURES OF BINARY SUPERMASSIVE BLACK HOLES
复制标题
双超大质量黑洞的观测特征
DOI：
--
复制
发表时间：
2014
期刊：
影响因子：
--
通讯作者：
M. Miller
中科院分区：
文献类型：
--
作者：
C. Roedig;J. Krolik;M. Miller
观测表明，大多数大质量星系都含有超大质量黑洞，理论研究表明，当此类星系发生重大合并时，中心黑洞将形成双星并最终合并。在这里，我们讨论此类双星的两个光谱特征，这可能有助于将它们与普通的活动星系核区分开来。当孔之间的质量比不是极端并且系统由环二元盘供给时，这些特征是预期的。其中一个特征是热连续体中的一个凹口，这已被其他作者所预测。我们指出它应该伴随着较短波长的光谱复兴，并讨论了它对二元特性（如质量、质量比和分离）的依赖性。特别是，我们注意到，出现陷波的波长 λn 取决于这三个参数，从而使得显示这些陷波的系统数量；因此，较长波长的搜索受到强烈青睐。这里首先讨论的第二个特征是硬X射线发射，其特征温度~100 keV具有类维恩光谱，是由来自环双星盘的流撞击单个黑洞周围的吸积盘时产生的激波的康普顿冷却产生的。我们研究了两个签名的可观察性。硬X射线信号可能特别有价值，因为它可以在事件发生前几十年提供黑洞合并的指标。
Observations indicate that most massive galaxies contain a supermassive black hole, and theoretical studies suggest that when such galaxies have a major merger, the central black holes will form a binary and eventually coalesce. Here we discuss two spectral signatures of such binaries that may help distinguish them from ordinary active galactic nuclei. These signatures are expected when the mass ratio between the holes is not extreme and the system is fed by a circumbinary disk. One such signature is a notch in the thermal continuum that has been predicted by other authors; we point out that it should be accompanied by a spectral revival at shorter wavelengths and also discuss its dependence on binary properties such as mass, mass ratio, and separation. In particular, we note that the wavelength λn at which the notch occurs depends on these three parameters in such a way as to make the number of systems displaying these notches ; longer wavelength searches are therefore strongly favored. A second signature, first discussed here, is hard X-ray emission with a Wien-like spectrum at a characteristic temperature ∼100 keV produced by Compton cooling of the shock generated when streams from the circumbinary disk hit the accretion disks around the individual black holes. We investigate the observability of both signatures. The hard X-ray signal may be particularly valuable as it can provide an indicator of black hole merger a few decades in advance of the event.
DOI：
10.1088/0004-637x/695/1/455
发表时间：
2008-12
期刊：
The Astrophysical Journal
影响因子：
--
作者：
I. Berentzen;Miguel Preto;P. Berczik;D. Merritt;R. Spurzem
通讯作者：
I. Berentzen;Miguel Preto;P. Berczik;D. Merritt;R. Spurzem