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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 codeMESAand implement a detailed method for common envelope and mass transfer. We perform simulations for donor masses between 7 M⊙and 20 M⊙with a neutron star (NS) companion of 1.4 M⊙and 2.0 M⊙ 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 M⊙, all BNS mergers are formed following a common envelope phase. For an NS mass of 2.0 M⊙, 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 dispersionσ= 265 km s−1. Regardless of the supernova prescription, we find more BNS mergers at subsolar metallicity compared to solar.
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Constraining solar electron number density via neutrino flavor data at Borexino
Understanding the physics of the deep solar interior, and the more exotic environs of core-collapse supernovae (CCSN) and binary neutron-star (NS) mergers, is of keen interest in many avenues of research. To date, this physics is based largely on simulations via forward integration. While these simulations provide valuable constraints, it could be insightful to adopt the “inverse approach” as a point of comparison. Within this paradigm, parameters of the solar interior are not output based on an assumed model, but rather are inferred based on real data.We take the specific case of solar electron number density, which historically is taken as output from the standard solar model. We show how one may arrive at an independent constraint on that density profile based on available neutrino flavor data from the Earth-based Borexino experiment. The inference technique’s ability to offer a unique lens on physics can be extended to other datasets, and to analogous questions for CCSN and NS mergers, albeit with simulated data.
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- Award ID(s):
- 2139004
- PAR ID:
- 10540486
- Publisher / Repository:
- Physical Review D
- Date Published:
- Journal Name:
- Physical review
- ISSN:
- 2470-0010
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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