Black Holes In Young Stellar Clusters

Abstract

We present theoretical models for stellar black hole (BH) properties in young, massive star clusters. Using a Monte Carlo code for stellar dynamics, we model realistic star clusters with $N\simeq 5\times 10^5$ stars and significant binary fractions (up to 50%) with self-consistent treatments of stellar dynamics and stellar evolution. We compute the formation rates and characteristic properties of single and binary BHs for various representative ages, cluster parameters, and metallicities. Because of dynamical interactions and supernova (SN) kicks, more single BHs end up retained in clusters compared to BHs in binaries. We also find that the ejection of BHs from a cluster is a strong function of initial density. In low-density clusters (where dynamical effects are negligible), it is mainly SN kicks that eject BHs from the cluster, whereas in high-density clusters (initial central density ${\rho }_c(0)\sim 10^5{M}_{\odot }{\mathrm{pc}}^{-3}$ in our models) the BH ejection rate is enhanced significantly by dynamics. Dynamical interactions of binary systems in dense clusters also modify the orbital period and eccentricity distributions while also increasing the probability of a BH having a more massive companion.

References in corpus (13)

• XMM-Newton observations of the brightest Ultraluminous X-ray sources
• A census of the Wolf-Rayet content in Westerlund 1 from near-infrared imaging and spectroscopy
• Dynamical evolution of black hole sub-systems in idealised star clusters
• A double main sequence turn-off in the rich star cluster NGC 1846 in the Large Magellanic Cloud
• Natal Kicks of Stellar-Mass Black Holes by Asymmetric Mass Ejection in Fallback Supernovae
• Low metallicity and ultra-luminous X-ray sources in the Cartwheel galaxy
• On the weakness of disc models in bright ULXs
• Irradiation models for ULXs and fits to optical data
• Do Ultraluminous X-Ray Sources Exist in Dwarf Galaxies?
• A Rich Population of X-ray Emitting Wolf-Rayet Stars in the Galactic Starburst Cluster Westerlund 1
• Populating the Galaxy with pulsars -- II. Galactic dynamics
• Further Wolf-Rayet stars in the starburst cluster Westerlund 1
• Elemental Abundances of Nearby Galaxies through High Signal-to-Noise XMM-Newton Observations of ULXs

Cited by in corpus (17)

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• Binary black holes in young star clusters: the impact of metallicity
• Stellar-mass black holes in young massive and open stellar clusters IV: updated stellar-evolutionary and black hole spin models and comparisons with the LIGO-Virgo O1/O2 merger-event data
• Constraining the formation of black-holes in short-period Black-Hole Low-Mass X-ray Binaries
• Gravitational-Wave Emission from Binary Black Holes Formed in Open Clusters
• Stellar Black Hole Binary Mergers in Open Clusters
• Merger rate density of binary black holes formed in open clusters
• Assessing inflow rates in atomic cooling halos: implications for direct collapse black holes
• Dynamics of binary black holes in low-mass young star clusters
• Neutron Star-Black Hole Mergers from Gravitational Wave Captures
• Do open star clusters evolve toward energy equipartition?
• Roche-lobe overflow systems powered by black holes in young star clusters: the importance of dynamical exchanges
• Dynamics of binary black holes in young star clusters: the impact of cluster mass and long-term evolution
• From hydrodynamics to N-body simulations of star clusters: mergers and rotation
• The ultraluminous X-ray source HoII X-1: kinematic evidence of its escape from the cluster