Tidal radii of main sequence stars -- III. Partial disruptions
Taeho Ryu, Julian Krolik, Tsvi Piran, Scott C. Noble
备注:
We have significantly revised this paper as a response to the referee's report. So we submitted the revised version with a new title as a new paper (arXiv:2001.03503) without replacing the old version
本文是这一系列研究的第三篇,我们继续研究非旋转$10^{6}~\rm{M}_\odot$超大质量黑洞对主序星的潮汐扰动事件。在这里,我们关注的是部分中断的结果。随着碰撞的减弱,碎片质量越来越集中在能量分布的外缘附近。结果,质量回退率可以实质上偏离$t^{-5/3}$幂律,变得更像具有尾部的单峰,如$t^{-p}$与$p\simeq2-5$。幸存的残余物以反方向旋转,并且比相同质量的MS星更热。它们的比轨道能量是碎片的$\simeq10^{-3}\times$(但相对于黑洞势,它们的符号是任意的),而它们的比角动量接近原始恒星的角动量。即使是强烈的碰撞,残余物的速度相对于黑洞势$\lesssim 300$ km s $^{-1}$也是无穷大的,所以它们不能走得很远进入银河系凸起。与黑洞绑定的残留物可能会经历第二次潮汐破坏事件。
英文摘要:
In this paper, the third in this series, we continue our study of tidal disruption events of main-sequence stars by a non-spinning $10^{6}~\rm{M}_\odot$ supermassive black hole. Here we focus on the outcomes of partial disruptions. As the encounter becomes weaker, the debris mass is increasingly concentrated near the outer edges of the energy distribution. As a result, the mass fallback rate can deviate substantially from a $t^{-5/3}$ power-law, becoming more like a single peak with a tail declining as $t^{-p}$ with $p\simeq2-5$. Surviving remnants are spun-up in the prograde direction and are hotter than MS stars of the same mass. Their specific orbital energy is $\simeq10^{-3}\times$ that of the debris (but of either sign with respect to the black hole potential) while their specific angular momentum is close to that of the original star. Even for strong encounters, remnants have speeds at infinity relative to the black hole potential $\lesssim 300$ km s$^{-1}$, so they are unable to travel far out into the galactic bulge. Remnants bound to the black hole can possibly go through a second tidal disruption event.
Tidal disruptions of main sequence stars -- III. Stellar mass dependence of the character of partial disruptions
本文是这一系列研究的第三篇,我们继续研究非旋转$10^{6}~\rm{M}_\odot$超大质量黑洞对主序星的潮汐扰动事件。在这里,我们专注于恒星质量依赖的部分中断的结果。随着碰撞的减弱,碎片质量越来越集中在能量分布的外缘附近。结果,质量回退率可以实质上偏离$t^{-5/3}$幂律,变得更像具有尾部的单峰,如$t^{-p}$与$p\simeq2-5$。幸存的残余物在赤道方向旋转,比相同质量的主序星更热。它们的比轨道能量是碎片的$\simeq10^{-3}\times$,但相对于黑洞势,它们的比角动量接近原始恒星的比角动量。即使是强烈的碰撞,残余物的速度相对于黑洞势$\lesssim 300$ km s $^{-1}$也是无穷大的,所以它们不能走得很远进入银河系凸起。与黑洞结合最深的残余物在第一次返回近心时经历了第二次潮汐破裂事件;如果它们没有热弛豫,它们将完全破裂。
Tidal Disruptions of White Dwarfs: Theoretical Models and Observational Prospects
进入黑洞潮汐半径的质量为$\lesssim$ $10^5$ M $_{\odot}$的白矮星注定会被潮汐力撕裂。在恒星黑洞和超大质量黑洞之间的这个质量范围内的黑洞还没有被最终确定,所以检测到白矮星的潮汐破裂将为中等质量黑洞的存在提供明确的证据。在这篇综述中,我们提出了一个理论和观测的瞬态事件,导致从白矮星的潮汐中断的中等质量黑洞。这包括讨论最新的模拟和预测的属性,观测搜索的结果,以及总结潜在的引力波发射将被检测与即将到来的任务。