Double tidal disruptions in galactic nuclei

TL;DR

This paper investigates how binary stars near a massive black hole can undergo sequential tidal disruptions, collisions, and mergers, leading to unique observational signatures and potential formation of magnetized stars that can produce jets.

Contribution

It introduces the concept of double tidal disruptions in galactic nuclei and explores their observational signatures and possible outcomes, such as magnetized star formation and jet production.

Findings

Binary stars can be sequentially disrupted by the MBH.

Tidal interactions can cause binary component collisions and mergers.

Merged stars may produce observable jets upon subsequent disruption.

Abstract

A star on a nearly radial trajectory approaching a massive black hole (MBH) gets tidally disrupted if it comes sufficiently close to the MBH. Here we explore what happens to binary stars whose centers of mass approach the MBH on nearly radial orbits. The interaction with the MBH often leads to both stars being disrupted in sequence. We argue that such events could produce light curves that are substantially different from those of the single disruptions, with possible features such as two local maxima. Tidal forces from the MBH can also lead the binary components to collide; these merger products can form highly magnetized stars, whose subsequent tidal disruption may enable prompt jet formation.