论文标题
潮汐破坏事件的动态统一
Dynamical Unification of Tidal Disruption Events
论文作者
论文摘要
已经观察到了大约一百个潮汐破坏事件(TDE),它们在峰值和一生中都表现出广泛的发射特性。一些TDE主要在X射线能量下峰值峰值,而另一些TDE则主要在紫外线和光波长下辐射。尽管跨TDE的峰值亮度显示出不同的特性,但在具有相似峰值发射特性的TDE之间,进化行为也会有所不同。在很晚时,一些光学TDE在X射线中重新布莱恩,而另一些光学TDE则保持强大的紫外线/光学发射组件。在这封信中,我们对TDE积聚磁盘进行了三维一般相对论辐射磁动力学模拟,以不同的吸积率从几个到几十浓度的增生速率。我们利用蒙特卡洛辐射转移模拟来计算各种倾向和不同进化阶段的后处理光谱。我们确认了Dai等人提出的统一模型。 (2018年),它预测观察到的发射在很大程度上取决于观察者相对于磁盘方向的视角(当对面对面时X射线强烈时X射线强,并且在查看磁盘时将紫外线/紫外线/光学上强)。更重要的是,我们发现具有较高积聚率的磁盘的风和磁盘密度升高,从而增加了高能辐射的重新处理,因此通常会沿特定的视角增加光学与X射线的磁通量。这意味着,随着积聚水平的下降,我们希望漏斗有效地打开,并允许更多X射线沿中间视角泄漏。 TDE的这种动力学模型可以为TDE在TDE及其时间演化时在TDE中观察到的发射特性的多样性提供自然的解释。
About a hundred tidal disruption events (TDEs) have been observed and they exhibit a wide range of emission properties both at peak and over their lifetimes. Some TDEs peak predominantly at X-ray energies while others radiate chiefly at UV and optical wavelengths. While the peak luminosities across TDEs show distinct properties, the evolutionary behavior can also vary between TDEs with similar peak emission properties. At late time, some optical TDEs rebrighten in X-rays, while others maintain strong UV/optical emission components. In this Letter, we conduct three-dimensional general relativistic radiation magnetohydrodynamics simulations of TDE accretion disks at varying accretion rates ranging from a few to a few tens of the Eddington accretion rate. We make use of Monte Carlo radiative transfer simulations to calculate the reprocessed spectra at various inclinations and at different evolutionary stages. We confirm the unified model proposed by Dai et al. (2018), which predicts that the observed emission largely depends on the viewing angle of the observer with respect to the disk orientation (X-ray strong when viewed face-on and UV/optically strong when viewed disk-on). What is more, we find that disks with higher accretion rates have elevated wind and disk densities, which increases the reprocessing of the high-energy radiation and thus generally augments the optical-to-X-ray flux ratio along a particular viewing angle. This implies that at later times, as the accretion level declines, we expect the funnel to effectively open up and allow more X-rays to leak out along intermediate viewing angles. Such dynamical model for TDEs can provide a natural explanation for the diversity in the emission properties observed in TDEs at peak and along their temporal evolution.