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Related papers: Lower-mass-gap Black Holes in Dense Star Clusters

200 papers

Whether intermediate-mass black holes reside in nearby star clusters has remained contested for decades. We address this question by training neural network and random forest regressors on synthetic catalogs generated with the {\sc Rapster}…

Astrophysics of Galaxies · Physics 2026-05-22 Konstantinos Kritos , Digvijay Wadekar , Emanuele Berti

We present an empirical approach for interpreting gravitational wave signals of binary black hole mergers under the assumption that the underlying black hole population is sourced by remnants of stellar evolution. Using the observed…

Astrophysics of Galaxies · Physics 2017-11-08 Oliver D. Elbert , James S. Bullock , Manoj Kaplinghat

Observations of gravitational waves and their electromagnetic counterparts may soon uncover the existence of coalescing compact binary systems formed by a stellar-mass black hole and a neutron star. These mergers result in a remnant black…

General Relativity and Quantum Cosmology · Physics 2020-01-31 Francesco Zappa , Sebastiano Bernuzzi , Francesco Pannarale , Michela Mapelli , Nicola Giacobbo

We investigate the impact of millicharged particles (MCPs) on massive stars undergoing pulsational pair-instability supernovae and on the location of the lower edge of the black hole mass gap. We find that energy losses due to MCP emission…

High Energy Physics - Phenomenology · Physics 2026-04-06 Damiano F. G. Fiorillo , Giuseppe Lucente , Jeremy Sakstein , Edoardo Vitagliano , Matteo Cantiello

Dynamical interactions in dense star clusters are considered one of the most effective formation channels of binary black holes (BBHs). Here, we present direct $N-$body simulations of two different star cluster families: low-mass…

Astrophysics of Galaxies · Physics 2022-10-12 Stefano Torniamenti , Sara Rastello , Michela Mapelli , Ugo N. Di Carlo , Alessandro Ballone , Mario Pasquato

Mergers between stellar-mass black holes will be key sources of gravitational radiation for ground-based detectors. However, the rates of these events are highly uncertain, given that such systems are invisible. One formation scenario…

Astrophysics · Physics 2009-06-23 M. Coleman Miller , Vanessa M. Lauburg

Recently, the LIGO-Virgo collaborations have reported the coalescence of a binary involving a black hole and a low-mass gap object (LMGO) with mass in the range $\sim2.5-5M_\odot$. Such detections, challenge our understanding of the black…

Astrophysics of Galaxies · Physics 2021-08-11 Konstantinos Kritos , Ilias Cholis

Dense star clusters are thought to contribute significantly to the merger rates of stellar-mass binary black holes (BBHs) detected by the LIGO-Virgo-KAGRA collaboration. We combine $N$-body dynamic models of realistic dense star clusters…

High Energy Astrophysical Phenomena · Physics 2026-04-07 Claire S. Ye , Maya Fishbach , Kyle Kremer , Marta Reina-Campos

Dense star clusters are promising nurseries for the formation and growth of intermediate-mass black holes (IMBHs; $\sim 10^2-10^5\,\mathrm{M}_{\odot}$), with increasing observational evidence pointing to their presence in massive star…

Astrophysics of Galaxies · Physics 2025-10-07 Abbas Askar , Marcelo C. Vergara , Sohaib Ali

The recent detection of GW190521 stimulated ideas on how to populate the predicted black hole pair-instability mass gap. One proposed scenario is the dynamical merger of two stars below the pair instability regime forming a star with a…

Solar and Stellar Astrophysics · Physics 2020-12-02 M. Renzo , M. Cantiello , B. D. Metzger , Y. -F. Jiang

It is firmly established that the stellar mass distribution is smooth, covering the range 0.1-100 Msun. It is to be expected that the masses of the ensuing compact remnants correlate with the masses of their progenitor stars, and thus it is…

Astrophysics of Galaxies · Physics 2015-05-30 K. Belczynski , G. Wiktorowicz , C. Fryer , D. Holz , V. Kalogera

The existence of a mass gap of $3-5\,M_{\odot}$ between the heaviest neutron stars (NSs) and the lightest black holes (BHs), inferred from the BH mass distribution in low mass X-ray binaries (LMXBs), has been suggested for decades. The…

The origin of the black hole (BH) binary mergers observed by LIGO-Virgo is still uncertain, as are the boundaries of the stellar BH mass function. Stellar evolution models predict a dearth of BHs both at masses $\gtrsim 50$ M$_\odot$ and…

Astrophysics of Galaxies · Physics 2020-05-27 Giacomo Fragione , Abraham Loeb , Frederic A. Rasio

We present direct N-body simulations, carried out with Nbody6++GPU, of young and compact low metallicity star clusters with $1.1\times 10^5$ stars, a velocity dispersion of $\sim$ 10 $\mathrm{km\,s^{-1}}$, a half mass radius $R_h=0.6$ pc,…

We review possible dynamical formation processes for central massive black holes in dense star clusters. We focus on the early dynamical evolution of young clusters containing a few thousand to a few million stars. One natural formation…

Astrophysics · Physics 2007-05-23 Frederic A. Rasio , Marc Freitag , M. Atakan Gürkan

In this letter we focus on the peculiar case of a coalescing compact-object binary whose chirp mass is compatible both with a neutron star-neutron star and black hole-neutron star system, with the black hole in the $\sim 3-5M_\odot$ range…

High Energy Astrophysical Phenomena · Physics 2020-01-08 Claudio Barbieri , Om Sharan Salafia , Monica Colpi , Giancarlo Ghirlanda , Albino Perego , Alberto Colombo

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…

Astrophysics of Galaxies · Physics 2022-03-30 Giacomo Fragione , Bence Kocsis , Frederic A. Rasio , Joseph Silk

Black holes below Chandrasekhar mass limit (1.4 $M_{\odot}$) can not be produced via any standard stellar evolution. Recently, gravitational wave experiments have also discovered unusually low mass black holes whose origin is yet to be…

High Energy Physics - Phenomenology · Physics 2023-07-06 Anupam Ray

Our current understanding of the stellar initial mass function and massive star evolution suggests that young globular clusters may have formed hundreds to thousands of stellar-mass black holes, the remnants of stars with initial masses…

Astrophysics of Galaxies · Physics 2015-06-22 Meagan Morscher , Bharath Pattabiraman , Carl Rodriguez , Frederic A. Rasio , Stefan Umbreit

The evolution of dense star clusters is followed by direct high-accuracy N-body simulation. The problem is to first order a gravitational N-body problem, but stars evolve due to astrophysics and the more massive ones form black holes or…