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arXiv · 2507.14428

Double tidal disruption events in the changing-look AGN Mrk1018

Zhang XueGuang
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Abstract

Tidal disruption events (TDEs) as excellent beacons to black hole (BH) accreting systems have been studied for more than five decades with a single star tidally disrupted by a central massive BH. However, if considering two stars passing through a central BH and being tidally disrupted in a short period, so-called double TDEs could be expected and lead to unique variability features very different from features from standard TDEs. Here, we report such oversimplified double TDEs in the known changing-look AGN Mrk1018, of which 15years-long light curve with plateau features can be described by two main-sequence stars tidally disrupted by the central supermassive BH. Meanwhile, the BH mass determined by the double TDEs is consistent with the M-sigma relation determined value by the measured stellar velocity dispersions in Mrk1018. The results indicate tight connections between the TDEs and the changing-look properties in Mrk1018.

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Zhang XueGuang. 2025-07-19. Double tidal disruption events in the changing-look AGN Mrk1018. https://arxiv.org/abs/2507.14428

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