Extreme variability in quasars

我正在研究类星体的极端可变性。类星体是宇宙中最明亮的物体，在某些情况下，它们的亮度可以在几个月的时间尺度上变化一个数量级。有许多机制可能导致这种活动，我将重点放在其中一种机制上--潮汐干扰事件(TDEs)。这是当恒星被驱动类星体的超大质量黑洞的潮汐力量撕裂时，暂时导致落在黑洞上的质量大幅增加。这导致了我们可以观察到的耀斑。研究这些极端事件为中央黑洞附近区域的物理和一般吸积物理提供了一个独特的试验台，虽然了解很少，但与许多天体物理现象有关。

I am studying extreme variability in quasars. Quasars are the most luminous objects in the universe, and in some cases their brightness can vary by an order of magnitude on timescales of months. There are a number of mechanisms that could cause this activity and I am focusing on one such mechanism - tidal disruption events (TDEs). This is when a star gets ripped apart by the tidal forces of the supermassive black hole that powers the quasar, temporarily causing a huge increase in mass falling onto the black hole. This leads to a flare up which we can observe. Studying these extreme events provides a unique testbed for physics in the region close to the central black hole and for accretion physics in general, which, though poorly understood, is relevant to a number of astrophysical phenomena.