Tidal disruption events onto stellar black holes in triples. (arXiv:1905.09471v1 [astro-ph.GA])
<a href="http://arxiv.org/find/astro-ph/1/au:+Fragione_G/0/1/0/all/0/1">Giacomo Fragione</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Leigh_N/0/1/0/all/0/1">Nathan Leigh</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Perna_R/0/1/0/all/0/1">Rosalba Perna</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kocsis_B/0/1/0/all/0/1">Bence Kocsis</a>

Stars passing too close to a black hole can produce tidal disruption events
(TDEs), when the tidal force across the star exceeds the gravitational force
that binds it. TDEs have usually been discussed in relation to massive black
holes that reside in the centres of galaxies or lurk in star clusters. In this
paper, we investigate the possibility that triple stars hosting a stellar black
hole (SBH) may be sources of TDEs. We start from a triple system made up of
three main sequence (MS) stars and model the supernova (SN) kick event that led
to the production of an inner binary comprised of a SBH. We evolve these
triples in isolation with a high precision $N$-body code and study their TDEs
as a result of Kozai-Lidov oscillations. We explore a variety of distributions
of natal kicks imparted during the SN event, various maximum initial
separations for the triples, and different distributions of eccentricities. We
show that the main parameter that governs the properties of the SBH-MS binaries
which produce a TDE in triples is the mean velocity of the natal kick
distribution. Smaller $sigma$’s lead to larger inner and outer semi-major axes
of the systems that undergo a TDE, smaller SBH masses, and longer timescales.
We find that the fraction of systems that produce a TDE is roughly independent
of the initial conditions, while estimate a TDE rate of $7.3times 10^{-5}-4.1
mathrm{yr}^{-1}$, depending on the prescriptions adopted for the SBH natal
kicks. This rate is almost comparable to the expected TDE rate for massive
black holes.

Stars passing too close to a black hole can produce tidal disruption events
(TDEs), when the tidal force across the star exceeds the gravitational force
that binds it. TDEs have usually been discussed in relation to massive black
holes that reside in the centres of galaxies or lurk in star clusters. In this
paper, we investigate the possibility that triple stars hosting a stellar black
hole (SBH) may be sources of TDEs. We start from a triple system made up of
three main sequence (MS) stars and model the supernova (SN) kick event that led
to the production of an inner binary comprised of a SBH. We evolve these
triples in isolation with a high precision $N$-body code and study their TDEs
as a result of Kozai-Lidov oscillations. We explore a variety of distributions
of natal kicks imparted during the SN event, various maximum initial
separations for the triples, and different distributions of eccentricities. We
show that the main parameter that governs the properties of the SBH-MS binaries
which produce a TDE in triples is the mean velocity of the natal kick
distribution. Smaller $sigma$’s lead to larger inner and outer semi-major axes
of the systems that undergo a TDE, smaller SBH masses, and longer timescales.
We find that the fraction of systems that produce a TDE is roughly independent
of the initial conditions, while estimate a TDE rate of $7.3times 10^{-5}-4.1
mathrm{yr}^{-1}$, depending on the prescriptions adopted for the SBH natal
kicks. This rate is almost comparable to the expected TDE rate for massive
black holes.

http://arxiv.org/icons/sfx.gif