Supercritical accretion and ULXs
Supercritical accretion and ULXs
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超临界吸积和 ULX
DOI：
10.1002/asna.201011509
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发表时间：
2011
期刊：
影响因子：
--
通讯作者：
K
中科院分区：
文献类型：
--
作者：
Mineshige;S.;Ohsuga;K
超临界（或超爱丁顿）吸积似乎发生在各种黑洞物体中，包括微类星体和超亮X射线源。在这里，我们阐述了超临界吸积流理论的基础上，我们的二维（2-D）的整体辐射流体动力学（RHD）和辐射磁流体动力学（RMHD）模拟。我们首先确认，实际上是没有限制的吸积率到黑洞。然后，我们讨论了几个值得注意的可观察到的特征的超临界流，即，温和的光束，相对论性，准直流出，和逆康普顿散射光谱的光学厚流出。对于正面观测者来说，最大视在（各向同性）光度为22 LE（其中LE是爱丁顿光度），可以在质量供应率为250 LE/c2的情况下实现。对于更高的质量供应速率，甚至更大的各向同性发光度是可能的。相反地，对于边缘观测者，视光度会小得多，甚至更低，如果圆盘最里面的明亮部分被外面的部分所遮蔽。还期望由辐射压力力加速并由洛伦兹力准直的高速（>0.5c）射流。我们预计大的动力学光度，10.1LE，和高质量流出率，10 LE/c2。这可能解释了ULX周围的大电离星云（© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA，魏因海姆）
Supercritical (or super‐Eddington) accretion seems to occur in various black hole objects, including microquasars and ultra‐luminous X‐ray sources. We, here, elucidate the theory of supercritical accretion flow based on our two‐dimensional (2‐D) global radiation‐hydrodynamic (RHD) and radiation‐magnetohydrodynamic (RMHD) simulations. We first confirm that there is practically no limit to the accretion rate onto black holes. We then discuss several noteworthy observable features of the supercritical flow; that is, mild beaming, relativistic, collimated outflow, and inverse‐Compton scattering spectra by optically thick outflow. For face‐on observers the maximum apparent (isotropic) luminosities of ∼22LE(withLE being the Eddington luminosity) can be achieved for the mass supply rate of ∼50LE/c2. Even larger isotropic luminosities are possible for higher mass supply rates. For edge‐on observers, conversely, the apparent luminosity will be much less. It will be even lower, if the the innermost bright part of the disk is obscured by the outer part. High velocity (>0.5c) jet accelerated by radiation‐pressure force and collimated by Lorentz force is also expected. We expect large kinetic luminosity, ∼0.1LE, and high mass outflow rate, ∼10LE/c2. This may account for large ionizing nebulae around ULXs (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)