Dynamical structure of highly eccentric discs with applications to tidal disruption events
Dynamical structure of highly eccentric discs with applications to tidal disruption events
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DOI：
10.1093/mnras/staa3459
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发表时间：
2020-11
影响因子：
4.8
通讯作者：
Elliot M. Lynch;G. Ogilvie
中科院分区：
文献类型：
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作者：
Elliot M. Lynch;G. Ogilvie
无论是潮汐中断事件循环或吸积直接作为高偏心光盘是目前的研究主题，似乎敏感地依赖于光盘热力学。这个问题的一个方面没有得到太多的关注是，一个高度偏心的光盘必须有一个强大的，非流体静力学的变化光盘刻度高度周围的每个轨道。作为对其他研究小组数值模拟的补充，我们利用偏心吸积盘的非线性理论研究了TDE盘的动力学结构。特别是，我们研究了每个椭圆轨道周围的物理量的变化，考虑到动力学的垂直结构，以及粘性耗散和辐射冷却。这些解决方案包括类似于模拟中看到的类似蜘蛛网的结构。我们发现的热不稳定性的存在，在高偏心盘辐射压力为主的证据。对于热稳定的解决方案，我们的许多模型表明失败的湍流应力的$\alpha-$处方。我们讨论了我们的结果偏心TDE光盘的结构的后果。
Whether tidal disruption events circularise or accrete directly as highly eccentric discs is the subject of current research and appears to depend sensitively on the disc thermodynamics. One aspect of this problem that has not received much attention is that a highly eccentric disc must have a strong, non-hydrostatic variation of the disc scale height around each orbit. As a complement to numerical simulations carried out by other groups, we investigate the dynamical structure of TDE discs using the nonlinear theory of eccentric accretion discs. In particular, we study the variation of physical quantities around each elliptical orbit, taking into account the dynamical vertical structure, as well as viscous dissipation and radiative cooling. The solutions include a structure similar to the nozzle-like structure seen in simulations. We find evidence for the existence of the thermal instability in highly eccentric discs dominated by radiation pressure. For thermally stable solutions many of our models indicate a failure of the $\alpha-$prescription for turbulent stresses. We discuss the consequences of our results for the structure of eccentric TDE discs.