Tidal Capture of Stars by Intermediate-Mass Black Holes
نویسندگان
چکیده
Recent X-ray observations and theoretical modelling have made it plausible that some ultraluminous X-ray sources (ULX) are powered by intermediate-mass black holes (IMBHs). N-body simulations have also shown that runaway merging of stars in dense star clusters is a way to form IMBHs. In the present paper we have performed N -body simulations of young clusters such as MGG-11 of M82 in which IMBHs form through runaway merging. We took into account the effect of tidal heating of stars by the IMBH to study the tidal capture and disruption of stars by IMBHs. Our results show that the IMBHs have a high chance of capturing stars through tidal heating within a few core relaxation times and we find that 1/3 of all runs contain a ULX within the age limits of MGG-11, a result consistent with the fact that a ULX is found in this galaxy. Our results strengthen the case for some ULX being powered by intermediate-mass black holes.
منابع مشابه
Evolution of Intermediate-Mass Black Hole X-Ray Binaries
The majority of the ultraluminous X-ray sources (ULXs) in external galaxies are believed to be accreting black holes in binary systems; some of the black holes could be as massive as ∼ 100 − 1000M⊙. We have performed evolution calculations for intermediate-mass black hole X-ray binaries, assuming they are formed in dense star clusters via tidal capture. The results are compared with those for s...
متن کاملFeeding black holes at galactic centres by capture from isothermal cusps
The capture rates of stars and dark particles onto supermassive black holes depend strongly on the spatial and kinematical distribution of the stellar and dark matter at the centre of bulges and elliptical galaxies. We here explore the possibility that all ellipticals/bulges have initially isothermal cusps (ρ ∝ r). If the orbits can be adequately randomized a significant fraction of the total m...
متن کاملThe M•–σ∗ relation for black holes fed by capturing stars and dark matter from an isothermal cusp
The capture rates of stars onto supermassive black holes depend strongly on the spatial and kinematical distribution of the stars at the centre of bulges and elliptical galaxies. We here explore the possibility that all ellipticals/bulges have initially isothermal cusps (ρ ∝ r). If the orbits can be adequately randomized a significant fraction of the total mass of black holes in the bulges of g...
متن کاملRevised Rates of Stellar Disruption in Galactic Nuclei
We compute rates of tidal disruption of stars by supermassive black holes in galactic nuclei, using downwardly revised black hole masses from the M• −σ relation. In galaxies with steep nuclear density profiles, which dominate the overall event rate, the disruption frequency varies inversely with assumed black hole mass. We compute a total rate for non-dwarf galaxies of ∼ 10−5 yr−1 Mpc−3, about ...
متن کاملar X iv : a st ro - p h / 04 06 23 1 v 1 9 J un 2 00 4 Massive Black Holes in Star Clusters . II . Realistic Cluster Models
We have followed the evolution of multi-mass star clusters containing massive central black holes through collisional N -body simulations done on GRAPE6. Each cluster is composed of between 16,384 to 131,072 stars together with a black hole with an initial mass of MBH = 1000M⊙. We follow the evolution of the clusters under the combined influence of two-body relaxation, stellar mass-loss and tid...
متن کامل