Tidal disruption events and quasi‑periodic eruptions

Abstract

Tidal disruption events (TDEs) occur when a star passes close to a massive black hole so that the tidal forces of the black hole exceed the binding energy of a star and cause it to be ripped apart. Part of the matter will fall onto the black hole, causing a strong increase in luminosity. Such events are often seen in the optical or the x‑ray (or both) or even at other wavelengths such as in the radio, where the diversity of observed emission is still poorly understood. The XMM‑Newton catalog of approximately a million x‑ray detections covering 1283 degrees of sky contains a number of these events. Here I will show the diverse nature of a number of TDEs discovered in the catalog and discuss their relationship with quasi‑periodic eruptions.