Merger Conditions of Population III Protostar Binaries
arXiv:2305.06843 · doi:10.3847/1538-4357/acd1e0
Abstract
Massive close binary stars with extremely small separations have been observed, and they are possible progenitors of gravitational-wave sources. The evolution of massive binaries in the protostellar accretion stage is key to understanding their formation process. We, therefore, investigate how close the protostars, consisting of a high-density core and a vast low-density envelope, can approach each other but not coalesce. To investigate the coalescence conditions, we conduct smoothed particle hydrodynamics simulations following the evolution of equal-mass binaries with different initial separations. Since Population (Pop) I and III protostars have similar interior structures, we adopt a specific Pop~III model with the mass and radius of and obtained by the stellar evolution calculations. Our results show that the binary separation decreases due to the transport of the orbital angular momentum to spin angular momentum. If the initial separation is less than about 80 per~cent of the sum of the protostellar radius, the binary coalesces in a time shorter than the tidal lock timescale. The mass loss up to the merging is per~cent. After coalescence, the star rotates rapidly, and its interior structure is independent of the initial separation. We conclude that there must be some orbital shrinking mechanism after the protostars contract to enter the zero-age main-sequence stage.
arXiv comment17 pages, 13 figures, Accepted for Publication in ApJ
References in corpus (70)
- The NumPy array: a structure for efficient numerical computation
- E pur si muove: Galiliean-invariant cosmological hydrodynamical simulations on a moving mesh
- Binary interaction dominates the evolution of massive stars
- Evolution of binary stars and the effect of tides on binary populations
- Stellar Multiplicity
- The Formation of Massive Stars from Turbulent Cores
- How small were the first cosmological objects?
- Stellar evolution with rotation VIII: Models at Z = 10^{-5} and CNO yields for early galactic evolution
- Simulations of Early Structure Formation: Primordial Gas Clouds
- The High Angular Resolution Multiplicity of Massive Stars
- Simulations on a Moving Mesh: The Clustered Formation of Population III Protostars
- Evolution of Massive Protostars with High Accretion Rates
- The early star generations: the dominant effect of rotation on the CNO yields
- Tidal Decay of Close Planetary Orbits
- The Formation and Fragmentation of Disks around Primordial Protostars
- Cosmological Formation of Low-Mass Objects
- Formation of the First Stars by Accretion
- The Mass Spectrum of the First Stars
- The Formation of Close Binary Systems by Dynamical Interactions and Orbital Decay
- The first stars: formation of binaries and small multiple systems
- A new Jeans resolution criterion for (M)HD simulations of self-gravitating gas: Application to magnetic field amplification by gravity-driven turbulence
- Possible Indirect Confirmation of the Existence of Pop III Massive Stars by Gravitational Wave
- Evolution of Massive Protostars via Disk Accretion
- The First Stars: Mass Growth Under Protostellar Feedback
- Formation of Massive Primordial Stars: Intermittent UV Feedback with Episodic Mass Accretion
- The generation of strong magnetic fields during the formation of the first stars
- The most metal-poor damped Lyman-alpha systems: Insights into chemical evolution in the very metal-poor regime
- Gravitational Waves from the Remnants of the First Stars
- Merging Neutron Stars I: Initial Results for Coalescence of Non-Corotating Systems
- Dynamical Formation of Close Binaries During the Pre-main-sequence Phase
- Formation of close binaries by disc fragmentation and migration, and its statistical modeling
- The Birth of a Massive First-Star Binary
- Stellar Yields of Rotating First Stars. II. Pair Instability Supernovae and Comparison with Observations
- Formation of Dwarf Galaxies during the Cosmic Reionization
- On the likelihood of detecting gravitational waves from Population III compact object binaries
- The Effects of Accretion Luminosity upon Fragmentation in the Early Universe
- Formation pathway of Population III coalescing binary black holes through stable mass transfer
- Merger rate density of Population III binary black holes below, above, and in the pair-instability mass gap
- The detection rate of Inspiral and Quasi-normal modes of Pop III binary black holes which can confirm or refute the General Relativity in the strong gravity region
- When did Population III star formation end?
- The mass of first stars
- A comprehensive set of simulations of high-velocity collisions between main sequence stars
- Formation sites of Population III star formation: The effects of different levels of rotation and turbulence on the fragmentation behavior of primordial gas
- Merge or survive: Number of Population III stars per minihalo
- Population III Binary Black Holes: Effects of Convective Overshooting on Formation of GW190521
- Baseline Metal Enrichment from Population III Star Formation in Cosmological Volume Simulations
- A systematic study of carbon-oxygen white dwarf mergers: mass combinations for Type Ia supernovae
- The importance of magnetic fields for the initial mass function of the first stars
- Discovery of the massive overcontact binary VFTS 352: Evidence for enhanced internal mixing
- Gravitational waves from Population III binary black holes formed by dynamical capture
- Smoothed Particle Hydrodynamics coupled with Radiation Transfer
- Merger rate density of binary black holes through isolated Population I, II, III and extremely metal-poor binary star evolution
- Evolution of Collisionally Merged Massive Stars
- Chirp Mass and Spin of Binary Black Holes from First Star Remnants
- Formation and Disruption of Cosmological Low Mass Objects
- Fragmentation induced starvation in Population III star formation: a resolution study
- Massive star formation by accretion I. Disc accretion
- The Orion Protostellar Explosion and Runaway Stars Revisited: Stellar Masses, Disk Retention, and an Outflow from BN
- Mass Transfer in Close, Rapidly Accreting Protobinaries: An Origin for Massive Twins?
- Forming Pop III binaries in self-gravitating disks: how to keep the orbital angular momentum
- The impact of very massive stars on the chemical evolution of extremely metal-poor galaxies
- Magnetohydrodynamic effect on first star formation: prestellar core collapse and protostar formation
- Companion-driven evolution of massive stellar binaries
- Amplification of turbulence in contracting prestellar cores in primordial minihalos
- Exponentially amplified magnetic field eliminates disk fragmentation around the Population III protostar
- Oxygen-enhanced extremely metal-poor DLAs: A signpost of the first stars?
- Supersonic Expansion of the Bipolar Hii Region Sh2-106: A 3,500 Year-Old Explosion?
- A strong neutron burst in jet-like supernovae of spinstars
- Impact of Magnetic Braking on High-mass Close Binary Formation
- Discrimination of heavy elements originating from Pop III stars in z = 3 intergalactic medium