Tidal Disruption of MainSequence Stars by IntermediateMass Black Holes
Abstract
We study close encounters of a $1\,M_{\odot}$ middleage mainsequence star (modelled using MESA) with massive black holes through hydrodynamic simulations, and explore in particular the dependence of the outcomes on the black hole mass. We consider here black holes in the intermediatemass range, $M_{\rm BH}= 10010^4\,M_{\odot}$. Possible outcomes vary from a small tidal perturbation for weak encounters all the way to partial or full disruption for stronger encounters. We find that stronger encounters lead to increased mass loss at the first pericenter passage, in many cases ejecting the partially disrupted star on an unbound orbit. For encounters that initially produce a bound system, with only partial stripping of the star, the fraction of mass stripped from the star increases with each subsequent pericenter passage and a stellar remnant of finite mass is ultimately ejected in all cases. We also find that the number of successive close passages before ejection decreases as we go from the stellarmass black hole to the intermediatemass black hole regime. For instance, after an initial encounter right at the classical tidal disruption limit, a $1\,M_{\odot}$ star undergoes 16 (5) pericenter passages before ejection from a $10\,M_{\odot}$ ($100\,M_{\odot}$) black hole. Observations of consecutive electromagnetic flares from these repeated close passages could in principle be used to determine the mass of the black hole, thus possibly proving the existence of intermediatemass black holes.
 Publication:

arXiv eprints
 Pub Date:
 October 2022
 arXiv:
 arXiv:2210.08002
 Bibcode:
 2022arXiv221008002K
 Keywords:

 Astrophysics  High Energy Astrophysical Phenomena
 EPrint:
 19 pages, 8 figures, 2 tables. Submitted to ApJ