Impact of initial mass functions on the dynamical channel of gravitational wave sources

Abstract

Dynamically formed black hole (BH) binaries (BBHs) are important sources of gravitational waves (GWs). Globular clusters (GCs) provide a major environment to produce such BBHs, but the total mass of the known GCs is small compared to that in the Galaxy; thus, the fraction of BBHs formed in GCs is also small. However, this assumes that GCs contain a canonical initial mass function (IMF) similar to that of field stars. This might not be true because several studies suggest that extreme dense and metal-poor environment can result in top-heavy IMFs, where GCs may originate. Although GCs with top-heavy IMFs were easily disrupted or have become dark clusters, the contribution to the GW sources can be significant. Using a high-performance and accurate $N$-body code, \textsc{petar}, we investigate the effect of varying IMFs by carrying out four star-by-star simulations of dense GCs with the initial mass of $5\times 10^5{M}_{\odot }$ and the half-mass radius of $2$~pc. We find that the BBH merger rate does not monotonically correlate with the slope of IMFs. Due to a rapid expansion, top-heavy IMFs lead to less efficient formation of merging BBHs. The formation rate continuously decreases as the cluster expands because of the dynamical heating caused by BHs. However, in star clusters with a top-heavier IMF, the total number of BHs is larger, and therefore, the final contribution to merging BBHs can still be more than from clusters with the standard IMF, if the initial cluster mass and density is higher than those used in our model.

arXiv comment10 pages, 12 figures, accepted for publication in MNRAS

References in corpus (66)

• On the variation of the Initial Mass Function
• GWTC-1: A Gravitational-Wave Transient Catalog of Compact Binary Mergers Observed by LIGO and Virgo during the First and Second Observing Runs
• Evolution of binary stars and the effect of tides on binary populations
• Comprehensive analytic formulae for stellar evolution as a function of mass and metallicity
• Compact Remnant Mass Function: Dependence on the Explosion Mechanism and Metallicity
• The formation of massive black holes through collision runaway in dense young star clusters
• Multiple Stellar Populations in Globular Clusters
• Black hole mergers in the universe
• On The Maximum Mass of Stellar Black Holes
• A new route towards merging massive black holes
• Binary Black Hole Mergers from Globular Clusters: Masses, Merger Rates, and the Impact of Stellar Evolution
• Merging binary black holes formed through chemically homogeneous evolution in short-period stellar binaries
• Gravitational waves from scattering of stellar-mass black holes in galactic nuclei
• The Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters. IX. The Atlas of Multiple Stellar Populations
• The Effect of Pair-Instability Mass Loss on Black Hole Mergers
• The evolutionary roads leading to low effective spins, high black hole masses, and O1/O2 rates of LIGO/Virgo binary black holes
• The progenitors of compact-object binaries: impact of metallicity, common envelope and natal kicks
• MOCCA-SURVEY Database I: Coalescing Binary Black Holes Originating From Globular Clusters
• The Evolution of Globular Clusters in the Galaxy
• Stellar Populations in the Central 0.5 pc of the Galaxy II: The Initial Mass Function
• Possible Indirect Confirmation of the Existence of Pop III Massive Stars by Gravitational Wave
• Evidence for top-heavy stellar initial mass functions with increasing density and decreasing metallicity
• Merging black holes in young star clusters
• An excess of massive stars in the local 30 Doradus starburst
• Dynamics of stellar black holes in young star clusters with different metallicities - II. Black hole-black hole binaries
• The DRAGON simulations: globular cluster evolution with a million stars
• Dynamical Formation of the GW150914 Binary Black Hole
• MOCCA Code for Star Cluster Simulations - IV. A new Scenario for Intermediate Mass Black Hole Formation in Globular Clusters
• Stellar populations dominated by massive stars in dusty starburst galaxies across cosmic time
• NBODY6++GPU: Ready for the gravitational million-body problem
• Dynamical evolution of black hole sub-systems in idealised star clusters
• Black hole triple dynamics: breakdown of the orbit average approximation and implications for gravitational wave detections
• Compact Binaries in Star Clusters I - Black Hole Binaries Inside Globular Clusters
• Monte-Carlo Simulations of Globular Cluster Evolution - I. Method and Test Calculations
• PeTar: a high-performance N-body code for modeling massive collisional stellar systems
• Implementation and performance of FDPS: A Framework Developing Parallel Particle Simulation Codes
• BSE versus StarTrack: implementations of new wind, remnant-formation, and natal-kick schemes in NBODY7 and their astrophysical consequences
• Black Hole Binaries Dynamically Formed in Globular Clusters
• Compact Binaries Ejected from Globular Clusters as GW Sources
• Science with the TianQin observatory: Preliminary results on stellar-mass binary black holes
• MOCCA-SURVEY Database I: Eccentric Black Hole Mergers During Binary-Single Interactions In Globular Clusters
• Binary Black Holes in Dense Star Clusters: Exploring the Theoretical Uncertainties
• Intermediate Mass Black Hole Formation in compact Young Massive Star Clusters
• Post-Newtonian Dynamics in Dense Star Clusters: Binary Black Holes in the LISA Band
• The Unusual Initial Mass Function of the Arches Cluster
• Million-Body Star Cluster Simulations: Comparisons between Monte Carlo and Direct $N$-body
• Dynamical evolution of stellar-mass black holes in dense stellar clusters: estimate for merger rate of binary black holes originating from globular clusters
• The possible role of stellar mergers for the formation of multiple stellar populations in globular clusters
• Gravitational-Wave Emission from Binary Black Holes Formed in Open Clusters
• Single-single gravitational-wave captures in globular clusters: Eccentric deci-Hertz sources observable by DECIGO and Tian-Qin
• A slow-down time-transformed symplectic integrator for solving the few-body problem
• Particle-Particle Particle-Tree: A Direct-Tree Hybrid Scheme for Collisional N-Body Simulations
• MOCCA Survey Database I: Dissolution of tidally filling star clusters harbouring BH subsystems
• The Global Mass Functions of 35 Galactic globular clusters: II. Clues on the Initial Mass Function and Black Hole Retention Fraction
• A new type of compact stellar population: dark star clusters
• Fortran interface layer of the framework for developing particle simulator FDPS
• The Detection Rates of Merging Binary Black Holes Originating from Star Clusters and Their Mass Function
• MOCCA SURVEY Database I: Binary Black Hole Mergers from Globular Clusters with Intermediate Mass Black Holes
• Accelerated FDPS --- Algorithms to Use Accelerators with FDPS
• A Possible Solution for the $M/L-[Fe/H]$ Relation of Globular Clusters in M31. II. the Age-Metallicity Relation
• A Possible Solution for the M/L-[Fe/H] Relation of Globular Clusters in M31: A metallicity and density dependent top-heavy IMF
• The survival of star clusters with black hole subsystems
• The impact of metallicity-dependent mass loss versus dynamical heating on the early evolution of star clusters
• The Lifetimes of Star Clusters Born with a Top-heavy IMF
• Black Hole Mergers Induced by Tidal Encounters with a Galactic Centre Black Hole
• A New Hybrid Technique for Modeling Dense Star Clusters

Cited by in corpus (16)

• Preparing the next gravitational million-body simulations: Evolution of single and binary stars in Nbody6++GPU, MOCCA and McLuster
• Merger rate density of binary black holes through isolated Population I, II, III and extremely metal-poor binary star evolution
• Compact Binary Coalescences: Astrophysical Processes and Lessons Learned
• Gravitational wave of intermediate-mass black holes in Population III star clusters
• HR 6819 is a binary system with no black hole -- revisiting the source with infrared interferometry and optical integral field spectroscopy
• The impact of primordial binary on the dynamical evolution of intermediate massive star clusters
• The Redshift Evolution of the Binary Black Hole Mass Distribution from Dense Star Clusters
• Multimass modelling of Milky Way globular clusters -- I. Implications on their stellar initial mass function above 1 M${}_{\odot }$
• Rapid formation of a very massive star >50000 $M_{\odot }$ and subsequently an IMBH from runaway collisions. Direct N-body and Monte Carlo simulations of dense star clusters
• Can Population III stars be major origins of both merging binary black holes and extremely metal poor stars?
• The formation of globular clusters with top-heavy initial mass functions
• The Pristine survey: XXVII. The extremely metal-poor stream C-19 stretches over more than 100 degrees
• Dark Star Clusters or Ultra-Faint Dwarf galaxies? Revisiting UMa3/U1
• Spin distribution of binary black holes formed in open clusters
• Massive star clusters detected by JWST as natural birth places to form intermediate-mass black holes
• Dynamical double black holes and their host cluster properties