Mass and Spin Growth of Very Massive Stars in Star Clusters Potentially Associated with Little Red Dots

Abstract

Using gravitational $N$-body simulations, we investigate the evolution of mass and spin for very massive stars (VMSs) in dense star clusters, which could subsequently evolve into Little Red Dots (LRDs). Our results show that VMS masses can reach $10^3$--$10^4{M}_{\odot }$, depending on the initial conditions of the host clusters. Notably, the VMS mass increases by up to a factor of three when accounting for the bloated state at the Hayashi track induced by stellar collisions, provided that this state is maintained at accretion rates exceeding $3\times 10^{-2}{M}_{\odot }{\mathrm{yr}}^{-1}$. In all cases, the spin of the VMS, when normalized to the dimensionless black hole (BH) spin parameter, exceeds $10$, although the mass and spin of VMSs after the post-main sequence phase could be decreased by the stellar evolution process. We nonetheless demonstrate that VMSs formed in dense star clusters can be highly spinning. Such a rapidly spinning VMS is expected to collapse into an intermediate-mass BH surrounded by a massive accretion disk. This BH-disk system could trigger powerful explosions and emit burst gravitational waves, similar to those observed in GW190521 and GW231123, for which the remnant BH masses are estimated to be $\gtrsim 100M_{\odot }$.

arXiv comment13 pages, 3 figures, 1 table, ApJ accepted

References in corpus (81)

• On the variation of the Initial Mass Function
• 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
• Mass-loss predictions for O and B stars as a function of metallicity
• The Nucleosynthetic Signature of Population III
• GW190521: A Binary Black Hole Merger with a Total Mass of $150M_{\odot }$
• Young massive star clusters
• The formation of massive black holes through collision runaway in dense young star clusters
• Star Clusters Across Cosmic Time
• Properties and astrophysical implications of the 150 Msun binary black hole merger GW190521
• On The Maximum Mass of Stellar Black Holes
• Pair-Instability Supernovae, Gravity Waves, and Gamma-Ray Transients
• Formation of Primordial Supermassive Stars by Rapid Mass Accretion
• How mergers magnetise massive stars
• MOCCA Code for Star Cluster Simulations - IV. A new Scenario for Intermediate Mass Black Hole Formation in Globular Clusters
• Runaway collisions in young star clusters. II. Numerical results
• The evolution of runaway stellar collision products
• Constraints from gravitational wave detections of binary black hole mergers on the ${}^{12}\mathrm{C}{\left(\alpha ,\gamma \right)}^{16}\mathrm{O}$ rate
• Discovery of a Luminous, Variable, Off-Center Source in the Nucleus of M82 with the Chandra HRC
• The Pair-Instability Mass Gap for Black Holes
• Rapidly Accreting Supergiant Protostars: Embryos of Supermassive Black Holes?
• 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
• Stellar Yields of Rotating First Stars. II. Pair Instability Supernovae and Comparison with Observations
• Structure and evolution of high-mass stellar mergers
• Intermediate Mass Black Hole Formation in compact Young Massive Star Clusters
• Core-halo Structure of Chemically Homogeneous Massive Star and Bending of Zero-Age Main-Sequence
• Can Gamma-Ray Burst Jets Break Out the First Stars?
• Fast-moving stars around an intermediate-mass black hole in Omega Centauri
• Runaway collisions in young star clusters. I. Methods and tests
• One-, Two-, and Three-dimensional Simulations of Oxygen Shell Burning Just Before the Core-Collapse of Massive Stars
• Formation of primordial supermassive stars by burst accretion
• A comprehensive set of simulations of high-velocity collisions between main sequence stars
• Relativistic collapse and explosion of rotating supermassive stars with thermonuclear effects
• Observing intermediate-mass black holes and the upper--stellar-mass gap with LIGO and Virgo
• Intermediate mass black holes from stellar mergers in young star clusters
• JADES -- The Rosetta Stone of JWST-discovered AGN: deciphering the intriguing nature of early AGN
• Exact and approximate expressions of energy generation rates and their impact on the explosion properties of Pair Instability Supernovae
• General Relativistic Instability Supernova of a Supermassive Population III Star
• Accretion modes in collapsars - prospects for GRB production
• A remarkable Ruby: Absorption in dense gas, rather than evolved stars, drives the extreme Balmer break of a Little Red Dot at $z=3.5$
• Collisions and close encounters involving massive main-sequence stars
• Very Massive Stars: a metallicity-dependent upper-mass limit, slow winds, and the self-enrichment of Globular Clusters
• Impact of the cosmic background radiation on the initial mass function of metal-poor stars
• Merger rate density of binary black holes through isolated Population I, II, III and extremely metal-poor binary star evolution
• A slow-down time-transformed symplectic integrator for solving the few-body problem
• Little red dots as young supermassive black holes in dense ionized cocoons
• Magnetorotational collapse of very massive stars to black holes in full general relativity
• Fitting formulae for evolution tracks of massive stars under extreme metal poor environments for population synthesis calculations and star cluster simulations
• Gravitational Collapse of Rotating Supermassive Stars including Nuclear Burning Effects
• Formation of supermassive stars in the first star clusters
• Simulations predict intermediate-mass black hole formation in globular clusters
• The Evolution towards Electron-capture Supernovae: the Flame Propagation and the Pre-bounce Electron-neutrino Radiation
• Can direct collapse black holes launch gamma-ray bursts and grow to supermassive black holes?
• Gravitational wave of intermediate-mass black holes in Population III star clusters
• Trojan Stars in the Galactic Center
• Stability analysis of supermassive primordial stars: a new mass range for general relativistic instability supernovae
• Deep silence: radio properties of little red dots
• Challenging the AGN scenario for JWST/NIRSpec LRD and non-LRD broad H$\alpha$ emitters in light of non-detection of NIRCam photometric variability and X-ray
• Formation of black holes in the pair-instability mass gap: Hydrodynamical simulations of a head-on massive star collision
• Accelerated FDPS --- Algorithms to Use Accelerators with FDPS
• Sizes and Stellar Masses of the Little Red Dots Imply Immense Stellar Densities
• Intermediate-mass Black Holes on the Run from Young Star Clusters
• Effect of mass loss due to stellar winds on the formation of supermassive black hole seeds in dense nuclear star clusters
• Another piece to the puzzle: radio detection of a JWST detected AGN candidate
• The radio properties of the JWST-discovered AGN
• Little Red Dots Are Nurseries of Massive Black Holes
• Evolution and explosions of metal enriched supermassive stars: proton rich general relativistic instability supernovae
• 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
• Pulsation-driven mass loss from massive stars behind stellar mergers in metal-poor dense clusters
• Black Hole Formation and Explosion from Rapidly Rotating Very Massive Stars
• Spectral Uniformity of Little Red Dots: A Natural Outcome of Coevolving Seed Black Holes and Nascent Starbursts
• Collision-induced mass loss and mass gain on an extremely massive star. An analytical approach and a static proto-globular cluster test-case
• Little Red Dots from Low-Spin Galaxies at High Redshifts
• Toward Black Hole Stars: supermassive black hole growth in nuclear clusters via stellar-object and gas accretion
• The Cliff: A Metal-Poor Little Red Dot Hosting an Overmassive Black Hole at $z=3.55$
• NEXUS: A Search for Nuclear Variability with the First Two JWST NIRCam Epochs
• Magnetic field generation in mergers of massive main-sequence stars
• Massive stellar cannibals: How stellar mergers drive mass-loss in extremely massive stars
• Signatures of Exploding Supermassive PopIII Stars at High Redshift in JWST, EUCLID and Roman Space Telescope