Merging black holes in young star clusters

  title={Merging black holes in young star clusters},
  author={Ugo N Di Carlo and Nicola Giacobbo and Michela Mapelli and Mario Pasquato and Mario Spera and Long Wang and Francesco Haardt},
  journal={Monthly Notices of the Royal Astronomical Society},
Searching for distinctive signatures, which characterize different formation channels of binary black holes (BBHs), is a crucial step towards the interpretation of current and future gravitational wave detections. Here, we investigate the demography of merging BBHs in young star clusters (SCs), which are the nursery of massive stars. We performed $4\times{} 10^3$ N-body simulations of SCs with metallicity $Z=0.002$, initial binary fraction $0.4$ and fractal initial conditions, to mimic the… Expand
Unexpectedly high formation rate of merging binary black holes in open clusters
Abstract Gravitational wave direct detections suggest that 30 M⊙ binary black holes (BBHs) commonly exist in the universe. One possible formation scenario of such BBHs is dynamical three-bodyExpand
Mass and Rate of Hierarchical Black Hole Mergers in Young, Globular and Nuclear Star Clusters
This work presents a fast semi-analytic approach to simulate hierarchical mergers in nuclear star clusters, globular clusters (GCs) and young star clusters (YSCs), finding that multiple formation channels are favored to reproduce the observed BBH population. Expand
Intermediate-mass black holes from stellar mergers in young star clusters
Intermediate-mass black holes (IMBHs) in the mass range $10^2\!-\!10^5\, \mathrm{M_{\odot }}$ bridge the gap between stellar black holes (BHs) and supermassive BHs. Here, we investigate theExpand
Effect of distant encounters on black hole binaries in globular clusters: Systematic increase of in-cluster mergers in the LISA band
We present the first systematic study on how distant weak interactions impact the dynamical evolution of merging binary black holes (BBHs) in dense stellar clusters. Recent studies indicate thatExpand
Black holes: The next generation—repeated mergers in dense star clusters and their gravitational-wave properties
When two black holes merge in a dense star cluster, they form a new black hole with a well-defined mass and spin. If that "second-generation" black hole remains in the cluster, it will continue toExpand
New insights on binary black hole formation channels after GWTC-2: young star clusters versus isolated binaries
With the recent release of the Second Gravitational Wave Transient Catalog (GWTC-2), which introduced dozens of new detections, we are at a turning point of gravitational wave astronomy, as we areExpand
Hierarchical black hole mergers in young, globular and nuclear star clusters: the effect of metallicity, spin and cluster properties
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 binaryExpand
Constraining the Fraction of Binary Black Holes Formed in Isolation and Young Star Clusters with Gravitational-wave Data
Ten binary black-hole mergers have already been detected during the first two observing runs of advanced LIGO and Virgo, and many more are expected to be observed in the near future. This opens theExpand
Dynamics of binary black holes in low-mass young star clusters
Young star clusters are dynamically active stellar systems and are a common birthplace for massive stars. Low-mass star clusters (∼300–103 M⊙) are more numerous than massive systems and areExpand
Implications of Eccentric Observations on Binary Black Hole Formation Channels
Orbital eccentricity is one of the most robust discriminators for distinguishing between dynamical and isolated formation scenarios of binary black hole mergers using gravitational-wave observatoriesExpand


The Detection Rates of Merging Binary Black Holes Originating from Star Clusters and Their Mass Function
Advanced LIGO achieved the first detection of the gravitational wave, which was from a merging binary black hole (BBH). In the near future, more merger events will be observed, and the massExpand
Gravitational-wave emission from binary black holes formed in open clusters
In order to investigate the formation rate of binary black holes (BBHs) in stellar clusters with a mass comparable to open clusters, we performed a series of direct $N$-body simulations of openExpand
Stellar black hole binary mergers in open clusters
In this paper we study the evolution of a primordial black hole binary (BHB) in a sample of over 1500 direct-summation $N-$body simulations of small-and intermediate-size isolated star clusters asExpand
Eccentric Black Hole Mergers Forming in Globular Clusters
We derive the probability for a newly formed binary black hole (BBH) to undergo an eccentric gravitational wave (GW) merger during binary-single interactions inside a stellar cluster. By integratingExpand
Dynamical Formation of Low-Mass Merging Black Hole Binaries like GW151226
Using numerical models for star clusters spanning a wide range in ages and metallicities (Z) we study the masses of binary black holes (BBHs) produced dynamically and merging in the local universeExpand
Binary Mergers and Growth of Black Holes in Dense Star Clusters
We model the dynamical evolution of primordial black holes (BHs) in dense star clusters using a simplified treatment of stellar dynamics in which the BHs are assumed to remain concentrated in anExpand
MOCCA-SURVEY Database - I. Coalescing binary black holes originating from globular clusters
In this first of a series of papers, we utilize results for around two thousand star cluster models simulated using the MOCCA code for star cluster evolution (Survey Database I) to determine theExpand
A new route towards merging massive black holes
Recent advances in gravitational-wave astronomy make the direct detection of gravitational waves from the merger of two stellar-mass compact objects a realistic prospect. Evolutionary scenariosExpand
Post-Newtonian Dynamics in Dense Star Clusters: Highly Eccentric, Highly Spinning, and Repeated Binary Black Hole Mergers.
Modelling the relativistic accelerations and gravitational-wave emission in isolated binaries and during three- and four-body encounters finds that nearly half of all binary black hole mergers occur inside the cluster, with about 10% of those mergers entering the LIGO/Virgo band with eccentricities greater than 0.1. Expand
Binary Black Hole Mergers from Globular Clusters: Masses, Merger Rates, and the Impact of Stellar Evolution
The recent discovery of GW150914, the binary black hole merger detected by Advanced LIGO, has the potential to revolutionize observational astrophysics. But to fully utilize this new window into theExpand