Review: Accretion Disk Evolution in Tidal Disruption Events

Abstract

This is a brief review of the recent progress in understanding the evolution of the accretion disks in tidal disruption events (TDEs). Special attention is paid to (1) thermal-viscous instability that causes the disk to transition from a thick state to a thin one, and back and forth, (2) interactions between the fallback material and existing disk. Challenges to the current model from late-time X-ray observations are highlighted and possible solutions are discussed.