The Stellar Merger Scenario for Black Holes in the Pair-instability Gap

Abstract

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 small core and an over-sized envelope. We explore this scenario with detailed stellar evolution calculations, starting with ad-hoc initial conditions enforcing no core growth during the merger. We outline the main challenges this scenario has to overcome, in particular the requirement to retain enough of its mass at merger time, in the subsequent evolution, and at core-collapse. We found that these massive merger products are likely helium-rich, and spend most of their remaining lifetime within regions of the Herzsprung-Russell diagram where envelope instabilities akin to luminous blue variable (LBV) eruptions are expected. An energetic estimate of the amount of mass loss neglecting the back-reaction of the star suggests that the total amount of mass that can be removed at low metallicity is . 1 M . This is small enough that at core-collapse our models are retaining sufficient mass to form black holes in the pair-instability gap similar to the recent ones detected by LIGO/Virgo. However, mass loss at the time of merger and the neutrino-driven mass loss at core collapse still need to be quantified for these models in order to confirm the viability of this scenario.

arXiv commentaccepted version to appear in ApJL

References in corpus (65)

• The NumPy array: a structure for efficient numerical computation
• Modules for Experiments in Stellar Astrophysics (MESA)
• Modules for Experiments in Stellar Astrophysics (MESA): Giant Planets, Oscillations, Rotation, and Massive Stars
• Modules for Experiments in Stellar Astrophysics (MESA): Binaries, Pulsations, and Explosions
• Modules for Experiments in Stellar Astrophysics (MESA): Convective Boundaries, Element Diffusion, and Massive Star Explosions
• Modules for Experiments in Stellar Astrophysics (MESA): Pulsating Variable Stars, Rotation, Convective Boundaries, and Energy Conservation
• Mass-loss predictions for O and B stars as a function of metallicity
• GW190521: A Binary Black Hole Merger with a Total Mass of $150M_{\odot }$
• Low Temperature Opacities
• Presupernova Evolution of Rotating Massive Stars I: Numerical Method and Evolution of the Internal Stellar Structure
• Mass Loss: Its Effect on the Evolution and Fate of High-Mass Stars
• Rotating Massive Main-Sequence Stars I: Grids of Evolutionary Models and Isochrones
• The evolution of rotating stars
• Pulsational Pair-Instability Supernovae
• Shell-model calculations of stellar weak interaction rates: II. Weak rates for nuclei in the mass range A=45-65 in supernovae environment
• Approximate input physics for stellar modelling
• Rapid and Bright Stellar-mass Binary Black Hole Mergers in Active Galactic Nuclei
• The rotation rates of massive stars: the role of binary interaction through tides, mass transfer and mergers
• Assisted Inspirals of Stellar Mass Black Holes Embedded in AGN Disks: Solving the "Final AU Problem"
• Updated Electron-Conduction Opacities: The Impact on Low-Mass Stellar Models
• Mind the gap: The location of the lower edge of the pair instability supernovae black hole mass gap
• Intermediate mass black holes in AGN disks: I. Production & Growth
• Merging black hole binaries with the SEVN code
• Merging black holes in young star clusters
• How mergers magnetise massive stars
• Very Low Energy Supernovae from Neutrino Mass Loss
• Thermodynamic functions of dense plasmas: analytic approximations for astrophysical applications
• Pulsational pair-instability supernovae in very close binaries
• Black hole and neutron star mergers in galactic nuclei
• Intermediate mass black holes in AGN disks II. Model predictions & observational constraints
• Coulomb tunneling for fusion reactions in dense matter: Path integral Monte Carlo versus mean field
• Luminous Blue Variables and superluminous supernovae from binary mergers
• Stellar Collisions and the Interior Structure of Blue Stragglers
• Local Radiation Hydrodynamic Simulations of Massive Star Envelopes at the Iron Opacity Peak
• Energetic eruptions leading to a peculiar hydrogen-rich explosion of a massive star
• The GW190521 Mass Gap Event and the Primordial Black Hole Scenario
• A Systematic Survey of the Effects of Wind Mass Loss Algorithms on the Evolution of Single Massive Stars
• Binary black holes in young star clusters: the impact of metallicity
• Binary black holes in the pair-instability mass gap
• Stellar Evolution in AGN Disks
• On Variations Of Pre-Supernova Model Properties
• Structure and evolution of high-mass stellar mergers
• Polluting the pair-instability mass gap for binary black holes through super-Eddington accretion in isolated binaries
• The luminosities of cool supergiants in the Magellanic Clouds, and the Humphreys-Davidson limit revisited
• Mass Ejection in Failed Supernovae: Variation with Stellar Progenitor
• Black Hole Accretion Discs and Luminous Transients in Failed Supernovae from Non-Rotating Supergiants
• Pulsational Pair-instability Supernovae. I. Pre-collapse Evolution and Pulsational Mass Ejection
• Three Dimensional Radiation Hydrodynamic Simulations of Massive Star Envelopes
• Predictions for the hydrogen-free ejecta of pulsational pair-instability supernovae
• The impact of stellar rotation on the black hole mass-gap from pair-instability supernovae
• Sensitivity of the lower-edge of the pair instability black hole mass gap to the treatment of time dependent convection
• Beyond the Standard Model Explanations of GW190521
• Formation of Binary Black Holes Similar to GW190521 with a Total Mass of $\sim 150M_{\odot }$ from Population III Binary Star Evolution
• Triggering jet-driven explosions of core-collapse supernovae by accretion from convective regions
• The Formation of a 70 Msun Black Hole at High Metallicity
• GW190412 as a Third-Generation Black Hole Merger from a Super Star Cluster
• Mixing in massive stellar mergers
• The quest for blue supergiants: binary merger models for the evolution of the progenitor of SN 1987A
• Constraining the Black Hole Initial Mass Function with LIGO/VIRGO Observations
• Missing in Action: New Physics and the Black Hole Mass Gap
• Ultra Long Gamma-Ray Bursts from the collapse of Blue Super Giant stars: an end-to-end simulation
• Modelling Luminous-Blue-Variable Isolation
• Massive Stellar Mergers as Precursors of Hydrogen-rich Pulsational Pair Instability Supernovae
• Centrifugally Driven Mass Loss and Outbursts of Massive Stars
• Binary black hole growth by gas accretion in stellar clusters

Cited by in corpus (49)

• Hierarchical mergers of stellar-mass black holes and their gravitational-wave signatures
• GWTC-2.1: Deep Extended Catalog of Compact Binary Coalescences Observed by LIGO and Virgo During the First Half of the Third Observing Run
• Hierarchical black hole mergers in young, globular and nuclear star clusters: the effect of metallicity, spin and cluster properties
• The Cosmic Evolution of Binary Black Holes in Young, Globular and Nuclear Star Clusters: Rates, Masses, Spins and Mixing Fractions
• GW231123: a Binary Black Hole Merger with Total Mass 190-265 $M_{\odot }$
• Maximum Black Hole mass across Cosmic Time
• Compact object mergers: exploring uncertainties from stellar and binary evolution with SEVN
• Search for intermediate mass black hole binaries in the third observing run of Advanced LIGO and Advanced Virgo
• Population III Binary Black Holes: Effects of Convective Overshooting on Formation of GW190521
• Search for subsolar-mass binaries in the first half of Advanced LIGO and Virgo's third observing run
• Understanding the high-mass binary black hole population from stable mass transfer and super-Eddington accretion in BPASS
• Resolving the Stellar-Collapse and Hierarchical-Merger origins of the Coalescing Black Holes
• Formation of black holes in the pair-instability mass gap: evolution of a post-collision star
• Gravitational Wave Astronomy With TianQin
• Cosmologically coupled compact objects: a single parameter model for LIGO--Virgo mass and redshift distributions
• Breaching the limit: formation of GW190521-like and IMBH mergers in young massive clusters
• Resolving The Peak Of The Black Hole Mass Spectrum
• Pre-supernova evolution and final fate of stellar mergers and accretors of binary mass transfer
• Impact of gas hardening on the population properties of hierarchical black hole mergers in AGN disks
• Binary black hole mergers from Population III stars: uncertainties from star formation and binary star properties
• Find the Gap: Black Hole Population Analysis with an Astrophysically Motivated Mass Function
• "Super-Kilonovae" from Massive Collapsars as Signatures of Black-Hole Birth in the Pair-instability Mass Gap
• Hierarchical binary black hole mergers in globular clusters: mass function and evolution with redshift
• Mass ejection in failed supernovae: equation of state and neutrino loss dependence
• Dynamics of binary black holes in young star clusters: the impact of cluster mass and long-term evolution
• Formation of black holes in the pair-instability mass gap: Hydrodynamical simulations of a head-on massive star collision
• GW190521 formation via three-body encounters in young massive star clusters
• Massive binary black holes from Population II and III stars
• Constraints on the contributions to the observed binary black hole population from individual evolutionary pathways in isolated binary evolution
• GW190521: tracing imprints of spin-precession on the most massive black hole binary
• Reconstructing the Genealogy of LIGO-Virgo Black Holes
• Prospects of gravitational-waves detections from common-envelope evolution with LISA
• High mass but low spin: an exclusion region to rule out hierarchical black-hole mergers as a mechanism to populate the pair-instability mass gap
• Mapping the Likelihood of GW190521 with Diverse Mass and Spin Priors
• Gravitational waves from mergers of Population III binary black holes: roles played by two evolution channels
• Euclid detectability of pair instability supernovae in binary population synthesis models consistent with merging binary black holes
• Evidence of the pair instability gap from black hole masses
• On the Formation of GW231123 in Population III Star Clusters
• Dynamical Formation Scenarios for GW190521 and Prospects for Decihertz Gravitational-Wave Astronomy with GW190521-Like Binaries
• Tracing the evolution of short-period binaries with super-synchronous fast rotators
• Hypercritical accretion during common envelopes in triples leading to binary black holes in the pair-instability-supernova mass gap
• The Influence of Disk Composition on the Evolution of Stars in the Disks of Active Galactic Nuclei
• Supernovae from stellar mergers and accretors of binary mass transfer: Implications for Type IIP, 1987A-like and interacting supernovae
• Black hole mass function shift in proto-stellar-clusters driven by gas accretion
• The structure and evolution of a high-mass stellar merger in the Hertzsprung gap
• Variable Blue Straggler Stars in Open Cluster NGC 6819 Observed in the Kepler 'Superstamp' Field
• Spin-up and spin distribution of stellar black holes grown by gas accretion in proto-stellar clusters
• The Role of High-mass Stellar Binaries in the Formation of High-mass Black Holes in Dense Star Clusters
• Capability for detection of GW190521-like binary black holes with TianQin