Related papers: Massive black hole binaries from runaway collision…
Current theoretical models predict a mass gap with a dearth of stellar black holes (BHs) between roughly $50\,M_\odot$ and $100\,M_\odot$, while, above the range accessible through massive star evolution, intermediate-mass BHs (IMBHs) still…
In this paper, we study the formation and dynamical evolution of black hole-black hole (BH-BH) binaries in young star clusters (YSCs), by means of N-body simulations. The simulations include metallicity-dependent recipes for stellar…
A luminous X-ray source is associated with a cluster (MGG-11) of young stars \~200pc from the center of the starburst galaxy M82. The properties of the X-ray source are best explained by a black hole with a mass of at least 350Msun, which…
The maximum mass of black holes formed in isolated binaries is determined by stellar winds and the interactions between the binary components. We consider for the first time fully self-consistent detailed stellar structure and binary…
There is both theoretical expectation and some observational clues that intermediate mass black holes reside in nuclei of globular clusters. In order to find an independent indicator for their existence, we investigate in this paper how an…
Intermediate-mass black holes (IMBHs) could form via runaway merging of massive stars in a young massive star cluster (YMC). We combine a suite of numerical simulations of YMC formation with a semi-analytic model for dynamical friction and…
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…
Following the discovery of a black hole (BH) with a mass of 10^3-10^6 M(sun) in a starburst galaxy M82, we study formation of such a BH via successive merging of stellar-mass BHs within a star cluster. The merging has a runaway…
In this paper we report results of collisional N-body simulations of the dynamical evolution of equal-mass star clusters containing a massive central black hole. Each cluster is composed of between 5,000 to 180,000 stars together with a…
We explore hierarchical black hole (BH) mergers in nuclear star clusters (NSCs), globular clusters (GCs) and young star clusters (YSCs), accounting for both original and dynamically assembled binary BHs (BBHs). We find that the median mass…
The detection of the binary black hole merger GW190521, with primary black hole mass $85^{+21}_{-14}$ ${\rm M}_{\odot}$, proved the existence of black holes in the theoretically predicted pair-instability gap ($\sim60-120 \, {\rm…
We consider spherical stellar clusters with a broad mass function and a relaxation time short enough so that the segregation of massive stars toward the centre occurs before they have time to evolve off the main sequence. The relaxational…
The existence of black holes (BHs) with masses in the range between stellar remnants and supermassive BHs has only recently become unambiguously established. GW190521, a gravitational wave signal detected by the LIGO/Virgo Collaboration,…
We study how runaway stellar collisions in high-redshift, metal-poor star clusters form very massive stars (VMSs) that can directly collapse to intermediate-mass black holes (IMBHs). We follow the evolution of a pair of neighbouring…
In low-metallicity environments, massive stars might avoid supernova explosion and directly collapse, forming massive (~25-80 solar masses) stellar black holes (MSBHs), at the end of their life. MSBHs, when hosted in young massive clusters,…
Young dense massive star clusters are a promising environment for the formation of intermediate mass black holes (IMBHs) through collisions. We present a set of 80 simulations carried out with Nbody6++GPU of 10 initial conditions for…
Close encounters and physical collisions between stars in young dense clusters may lead to the formation of very massive stars and black holes via runaway merging. We examine critically some details of this process, using N-body simulations…
Most stars form in dense stellar environments. It is speculated that some dense star clusters may host intermediate-mass black holes (IMBHs), which may have formed from runaway collisions between high-mass stars, or from the mergers of less…
We investigate the evolution of intermediate-mass (IMBHs), stellar (BHs) and binary black holes (BHBs), deposited near a supermassive black hole (SMBH) by a population of massive star clusters. Stellar BHs rapidly segregate around the SMBH,…
Recently, an intermediate-mass black hole (IMBH) candidate was announced in the Galactic globular cluster Omega Centauri. IMBHs at the lower end of the traditional mass range have also been detected through gravitational-wave transients,…