Abstract
The formation histories of compact binary mergers, especially stellar-mass binary black hole mergers, have recently come under increased scrutiny and revision. We revisit the question of the dominant formation channel and efficiency of forming binary neutron star (BNS) mergers. We use the stellar and binary evolution code MESA and implement a detailed method for common envelope and mass transfer. We perform simulations for donor masses between 7 Me and 20 Me with a neutron star (NS) companion of 1.4 Me and 2.0 Me at two metallicities, using varying common envelope efficiencies and two different prescriptions to determine if the donor undergoes core collapse or electron capture, given their helium and carbon–oxygen cores. In contrast to the case of binary black hole mergers, for an NS companion of 1.4 Me, all BNS mergers are formed following a common envelope phase. For an NS mass of 2.0 Me, we identify a small subset of mergers following only stable mass transfer if the NS receives a natal kick sampled from a Maxwellian distribution with velocity dispersion σ = 265 km s−1. Regardless of the supernova prescription, we find more BNS mergers at subsolar metallicity compared to solar.
| Original language | English (US) |
|---|---|
| Article number | ace434 |
| Journal | Astrophysical Journal |
| Volume | 955 |
| Issue number | 2 |
| DOIs | |
| State | Published - Oct 1 2023 |
Funding
The authors thank the referee for comments on the manuscript; Meng Sun, Jeff Andrews, and Aaron Dotter for their feedback and assistance with our MESA simulations; Chase Kimball for discussions on SN prescriptions; Michael Zevin and the POSYDON collaboration (posydon.org) for useful discussions on stellar evolution; and Zoheyr Doctor for feedback on the manuscript. M.G.-G. is grateful for the support from the Ford Foundation Predoctoral Fellowship. C.P.L.B. acknowledges past support from the CIERA Board of Visitors Research Professorship and current support from the University of Glasgow. V.K. is supported by a CIFAR G+EU Senior Fellowship, by the Gordon and Betty Moore Foundation through grant GBMF8477, and by Northwestern University. This work utilized the computing resources at CIERA provided by the Quest high-performance computing facility at North-western University, which is jointly supported by the Office of the Provost, the Office for Research, and Northwestern University Information Technology, and used computing resources at CIERA funded by NSF PHY-1726951. Input files and data products are available for download from Zenodo at doi:10.5281/zenodo.7304993.\uF0A0The repository contains the input and data files to reproduce Figures 1 and 2 and the MESA inlist files\uF0A0used in our simulations.
Keywords
- Common envelope evolution (2154)
- Neutron stars (1108)
- Roche lobe overflow (2155)
- Stellar evolutionary models (2046)
- Unified Astronomy Thesaurus concepts: Gravitational wave sources (677)
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Space and Planetary Science