Stellar collisions in flattened and rotating Pop. III star clusters

Abstract

Fragmentation often occurs in disk-like structures, both in the early Universe and in the context of present-day star formation. Supermassive black holes (SMBHs) are astrophysical objects whose origin is not well understood; they weigh millions of solar masses and reside in the centers of galaxies. An important formation scenario for SMBHs is based on collisions and mergers of stars in a massive cluster, in which the most massive star moves to the center of the cluster due to dynamical friction. This increases the rate of collisions and mergers since massive stars have larger collisional cross sections. This can lead to runaway growth of a very massive star which may collapse to become an intermediate-mass black hole. Here we investigate the dynamical evolution of Miyamoto-Nagai models that allow us to describe dense stellar clusters, including flattening and different degrees of rotation. We find that the collisions in these clusters depend mostly on the number of stars and the initial stellar radii for a given radial size of the cluster. By comparison, rotation seems to affect the collision rate by at most $20\%$. For flatness, we compared spherical models with systems that have a scale height of about $10\%$ of their radial extent, in this case finding a change in the collision rate of less than $25\%$. Overall, we conclude that the parameters only have a minor effect on the number of collisions. Our results also suggest that rotation helps to retain more stars in the system, reducing the number of escapers by a factor of $2-3$ depending on the model and the specific realization. After two million years, a typical lifetime of a very massive star, we find that about $630$ collisions occur in typical models with $N=10^4$, $R=100$ ${\mathrm{R}}_{\odot }$ and a half-mass radius of $0.1$ $\mathrm{pc}$, leading to a mass of about $6.3\times 10^3$ ${\mathrm{M}}_{\odot }$ for the most massive object.

arXiv comment10 pages, 7 figures

References in corpus (47)

• A Fundamental Relation Between Supermassive Black Holes and Their Host Galaxies
• First M87 Event Horizon Telescope Results. I. The Shadow of the Supermassive Black Hole
• Coevolution (Or Not) of Supermassive Black Holes and Host Galaxies
• The Demography of Massive Dark Objects in Galaxy Centres
• The Nucleosynthetic Signature of Population III
• Measuring Distance and Properties of the Milky Way's Central Supermassive Black Hole with Stellar Orbits
• The M-sigma and M-L Relations in Galactic Bulges and Determinations of their Intrinsic Scatter
• A luminous quasar at a redshift of z = 7.085
• The Galactic Center Massive Black Hole and Nuclear Star Cluster
• An 800-million-solar-mass black hole in a significantly neutral Universe at redshift 7.5
• Formation of the First Supermassive Black Holes
• Formation of Supermassive Black Holes
• A Survey of z>5.7 Quasars in the Sloan Digital Sky Survey II: Discovery of Three Additional Quasars at z>6
• Star formation through gravitational collapse and competitive accretion
• The Pan-STARRS1 distant z>5.6 quasar survey: more than 100 quasars within the first Gyr of the universe
• The Formation and Fragmentation of Disks around Primordial Protostars
• Formation of Primordial Supermassive Stars by Rapid Mass Accretion
• Dynamical mass segregation on a very short timescale
• Can Supermassive Black Holes Form in Metal-Enriched High-Redshift Protogalaxies ?
• Accretion in stellar clusters and the IMF
• A dynamical origin for early mass segregation in young star clusters
• Rapidly Accreting Supergiant Protostars: Embryos of Supermassive Black Holes?
• On the rate of black hole binary mergers in galactic nuclei due to dynamical hardening
• The early dynamical evolution of cool, clumpy star clusters
• The Evolution of Supermassive Population III Stars
• The characteristic black hole mass resulting from direct collapse in the early universe
• Massive black hole factories: Supermassive and quasi-star formation in primordial halos
• On the Maximum Mass of Accreting Primordial Supermassive Stars
• Formation of Intermediate-Mass Black Holes through Runaway Collisions in the First Star Clusters
• Formation of massive seed black holes via collisions and accretion
• Supermassive Star Formation via Super Competitive Accretion in Slightly Metal-enriched Clouds
• Collisions in Primordial Star Clusters: Formation Pathway for intermediate mass black holes
• A comprehensive set of simulations of high-velocity collisions between main sequence stars
• Making a supermassive star by stellar bombardment
• Self-consistent models of quasi-relaxed rotating stellar systems
• High redshift formation and evolution of central massive objects I: model description
• Impact of dust cooling on direct collapse black hole formation
• The Scaled Universe
• Mass segregation in star clusters is not energy equipartition
• On the origins of enigmatic stellar populations in Local Group galactic nuclei
• Formation of supermassive black hole seeds in nuclear star clusters via gas accretion and runaway collisions
• Growth of intermediate mass black holes by tidal disruption events in the first star clusters
• The energetics of flat and rotating early-type galaxies and their X-ray luminosity
• How fast is mass-segregation happening in hierarchical formed embedded star clusters?
• The effects of a background potential in star cluster evolution: a delay in the relaxation time-scale and runaway collision processes
• Rapid dynamical mass segregation and properties of fractal star clusters
• The formation of the primitive star SDSS J102915+172927: effect of the dust mass and the grain-size distribution

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• Origin of supermassive black holes in massive metal-poor protoclusters
• The impact of stellar evolution on rotating star clusters: the gravothermal-gravogyro catastrophe and the formation of a bar of black holes
• Global instability by runaway collisions in nuclear stellar clusters: Numerical tests of a route for massive black hole formation
• Effect of mass loss due to stellar winds on the formation of supermassive black hole seeds in dense nuclear star clusters
• Transient stellar collisions as multimessenger probes: Non-thermal-, gravitational wave emission and the cosmic ladder argument
• 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
• Supermassive black hole formation via collisions in black hole clusters
• Efficiency of black hole formation via collisions in stellar systems: An analysis of data from simulations and observations
• Role of magnetic fields in the formation of direct collapse black holes
• Massive black hole formation in Population III star clusters
• The physical origin of super-competitive accretion during the formation of the first supermassive black holes
• Evolution of the mass relation between supermassive black holes and dark matter halos across the cosmic time
• Formation of supermassive stars in the first stellar clusters: Dependence on the gas temperature
• A direct N-body integrator for modelling the chaotic, tidal dynamics of multi-body extrasolar systems: TIDYMESS
• Tidal Disruption Events by Compact Supermassive Black Hole Binaries
• Predicting stellar collision outcomes of main sequence stars
• Gravitational collapse at low to moderate Mach numbers: The relationship between star formation efficiency and the fraction of mass in the massive object
• Super-Eddington Growth Ceiling: Analytic Constraints on the Rapid Growth of Light-Seed Black Holes in Massive Clumps
• Studying The Effect of Radiation Pressure on Evolution of a Population III Stellar Cluster
• Massive star clusters detected by JWST as natural birth places to form intermediate-mass black holes
• Direct N-body simulations of rotating and extremely massive Population III star clusters