Facial reconstruction

Search LJMU Research Online

Browse Repository | Browse E-Theses

Tidal disruption of inclined or eccentric binaries by massive black holes

Brown, H, Kobayashi, S, Rossi, EM and Sari, R (2018) Tidal disruption of inclined or eccentric binaries by massive black holes. Monthly Notices of the Royal Astronomical Society, 477 (4). pp. 5682-5691. ISSN 0035-8711

Tidal disruption of inclined or eccentric binaries by massive black holes.pdf - Published Version

Download (1MB) | Preview


Binary stars that are on close orbits around massive black holes (MBHs) such as Sgr A∗ in the centre of the Milky Way are liable to undergo tidal disruption and eject a hypervelocity star. We study the interaction between such an MBH and circular binaries for general binary orientations and penetration depths (i.e. binaries penetrate into the tidal radius around the BH). We show that for very deep penetrators, almost all binaries are disrupted when the binary rotation axis is roughly oriented towards the BH or it is in the opposite direction. The surviving chance becomes significant when the angle between the binary rotation axis and the BH direction is between 0.15π and 0.85π. The surviving chance is as high as ∼20 per cent when the binary rotation axis is perpendicular to the BH direction. However, for shallow penetrators, the highest disruption chance is found in such a perpendicular case, especially in the prograde case. This is because the dynamics of shallow penetrators is more sensitive to the relative orientation of the binary and orbital angular momenta. We provide numerical fits to the disruption probability and energy gain at the BH encounter as a function of the penetration depth. The latter can be simply rescaled in terms of binary masses, their initial separation, and the binary-to-BH mass ratio to evaluate the ejection velocity of a binary members in various systems. We also investigate the disruption of coplanar, eccentric binaries by an MBH. It is shown that for highly eccentric binaries retrograde orbits have a significantly increased disruption probability and ejection velocities compared to the circular binaries.

Item Type: Article
Additional Information: This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society ©: 2018 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.
Uncontrolled Keywords: 0201 Astronomical And Space Sciences
Subjects: Q Science > QB Astronomy
Q Science > QC Physics
Divisions: Astrophysics Research Institute
Publisher: Oxford University Press
Related URLs:
Date Deposited: 17 Jul 2018 10:36
Last Modified: 04 Sep 2021 02:34
DOI or ID number: 10.1093/mnras/sty1069
URI: https://researchonline.ljmu.ac.uk/id/eprint/8968
View Item View Item