标题： 收敛的流入光谱是黑洞的固有特征：自由下落电子上的康普顿化蒙特卡罗模拟 显示英文标题

标题： The converging inflow spectrum is an intrinsic signature for a black hole: Monte-Carlo simulations of Comptonization on free-falling electrons

摘要： 吸积黑洞，根据定义，其特征是存在吸积盘。 也就是说，物质以类似于水流入排水口的方式落入黑洞——物质进入其中，没有任何东西出来。 由于这种情况只能在黑洞中发生，因此提供了一种独特的方式来观察它。 吸积过程在黑洞视界附近几乎处于自由下落状态。 在本文中，我们通过使用蒙特卡罗模拟计算了在黑洞约3个史瓦西半径范围内的汇聚流入（CI）中，软（盘）光子向上散射形成的X射线谱的特定特征。 已经实施了完整的相对论处理来再现这些谱。 我们表明，黑洞系统在软态的谱可以描述为热（盘）成分和该成分的一部分与CI向上散射扩散函数的卷积之和。 后者增强的光子成分在远高于特征软光子能量的能量处表现为扩展的幂律。 我们证明了功率谱指数（alpha= 1.8）在等离子体温度0-10 keV和质量吸积率（高于2个爱丁顿单位）的广泛范围内是稳定的。 我们还证明了在200-400 keV能量处出现尖锐的高能截止，这与撞击视界的电子的平均静止能量有关。 当CI等离子体温度达到约50 keV（BHS的硬态）时，谱几乎与标准热康普顿化谱相同。 此外，从软X射线态到硬X射线态的谱形变化显然与整体流动的温度有关。 这些蒙特卡罗模拟的CI谱是BHS不可避免的标志。 显示英文摘要

摘要： An accreting black hole is, by definition, characterized by the drain. Namely, the matter falls into a black hole much the same way as water disappears down a drain - matter goes in and nothing comes out. As this can only happen in a black hole, it provides an unique way to see it. The accretion proceeds almost in free fall close to the black hole horizon. In this paper we calculate (by using Monte -Carlo simulations) the specific features of X-ray spectra formed as a result of upscattering of the soft (disk) photons in the converging inflow (CI) within about 3 Schwarzschild radii of the black hole. The full relativistic treatment has been implemented to reproduce these spectra. We show that spectra in the soft state of black hole systems can be described as the sum of a thermal (disk) component and the convolution of some fraction of this component with the CI upscattering spread function. The latter boosted photon component is seen as an extended power-law at energies much higher than the characteristic soft photons energy. We demonstrate the stability of the power spectral index (alpha= 1.8) over a wide range of the plasma temperature 0-10 keV and mass accretion rates (higher than 2 in Eddington units). We also demonstrate that the sharp high energy cutoff occurs at energies of 200-400 keV which are related to the average rest energy of electrons impinging upon the horizon. The spectrum is practically identical to the standard thermal Comptonization spectrum when the CI plasma temperature is getting of order of 50 keV (hard state of BHS). Also, the change of spectral shapes from the soft to the hard X-ray state is clearly to be related with the temperature of the bulk flow. These Monte-Carlo simulated CI spectra are then a inevitable stamp of the BHS.