GLOBAL SLIM ACCRETION DISK SOLUTIONS REVISITED
GLOBAL SLIM ACCRETION DISK SOLUTIONS REVISITED
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DOI：
10.1088/0004-637x/693/1/670
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发表时间：
2008-11
期刊：
影响因子：
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通讯作者：
Cheng-Liang Jiao;L. Xue;Weimin Gu;Ju-fu Lu
中科院分区：
文献类型：
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作者：
Cheng-Liang Jiao;L. Xue;Weimin Gu;Ju-fu Lu
我们发现，存在一个最大可能的吸积率，超过这个全球薄盘的解决方案不能构建，因为在垂直方向上的引力将无法平衡的压力，收集吸积物质。这种限制的原理与爱丁顿光度和相应的临界吸积率的原理相同，它们是通过考虑径向上相同的力平衡而导出的。如果放弃流体静力平衡的假设，而把垂直运动包括在内，则随着最大可能吸积速率的值变得更小，这种限制可能变得更加严重。以前的理解，在文献中，全球薄盘解决方案可以代表任何大的吸积率是由于高估的垂直引力使用近似的潜力。对于在大半径处具有大吸积率的吸积流，为了使吸积流减小吸积率并遵循全局解直到中心黑洞，流出似乎是不可避免的。
We show that there exists a maximal possible accretion rate, beyond which global slim disk solutions cannot be constructed because in the vertical direction the gravitational force would be unable to balance the pressure force to gather the accreted matter. The principle for this restriction is the same as that for the Eddington luminosity and the corresponding critical accretion rate, which were derived for spherical accretion by considering the same force balance in the radial direction. If the assumption of hydrostatic equilibrium is waived and vertical motion is included, this restriction may become even more serious as the value of the maximal possible accretion rate becomes smaller. Previous understanding in the literature that global slim disk solutions could stand for any large accretion rates is due to the overestimation of the vertical gravitational force by using an approximate potential. For accretion flows with large accretion rates at large radii, outflows seem unavoidable in order for the accretion flow to reduce the accretion rate and follow a global solution till the central black hole.