Modeling the UV/Optical light curve of re-brightening tidal disruption events

TL;DR

This paper introduces a new model for re-brightening tidal disruption events (TDEs) that involves a star experiencing two partial disruptions, successfully fitting observed light curves and predicting future flares.

Contribution

The authors develop a novel model and fitting code specifically for re-brightening TDEs caused by consecutive partial disruptions, addressing limitations of previous single-flare models.

Findings

The model accurately fits the light curves of AT 2022dbl and AT 2023adr.

Predictions for future flare timing and brightness are provided.

The model offers a new explanation for re-brightening features in TDEs.

Abstract

In recent years, a new subclass of tidal disruption events (TDEs) was reported from the literature. The light curve of these TDEs show a re-brightening feature in the decline phase after the first peak, which then leads to a second flare. The re-brightening TDEs challenges the existing light curve fitting tools, which are designed to handle single flare. In this work, we present a model, aimed at reproducing of the light curve of the re-brightening TDEs, based on the scenario that the consecutive flares are produced by the same star who experienced two partial disruptions (PTDEs). We also develop a fitting code from this model, and apply it to two re-brightening TDEs: AT 2022dbl and AT 2023adr. The light curve of both TDEs are well fitted. Finally, we forecast the time and peak brightness of the next flare for these two TDEs, so that the observers could get prepared in advance and make an examination on our model.