Resolving the Peak of the Black Hole Mass Spectrum
Abstract

Gravitational-wave (GW) detections of binary black hole (BH) mergers have begun to sample the cosmic BH mass distribution. The evolution of single stellar cores predicts a gap in the BH mass distribution due to pair-instability supernovae (PISNe). Determining the upper and lower edges of the BH mass gap can be useful for interpreting GW detections of merging BHs. We useMESAto evolve single, nonrotating, massive helium cores with a metallicity ofZ= 10−5, until they either collapse to form a BH or explode as a PISN, without leaving a compact remnant. We calculate the boundaries of the lower BH mass gap for S-factors in the range S(300 keV) = (77,203) keV b, corresponding to the ±3σuncertainty in our high-resolution tabulated12C(α,γ)16O reaction rate probability distribution function. We extensively test temporal and spatial resolutions for resolving the theoretical peak of the BH mass spectrum across the BH mass gap. We explore the convergence with respect to convective mixing and nuclear burning, finding that significant time resolution is needed to achieve convergence. We also test adopting a minimum diffusion coefficient to help lower-resolution models reach convergence. We establish a new lower edge of the upper mass gap asMlower$60−14+32$Mfrom the ±3σuncertainty in more »

Authors:
; ; ; ;
Publication Date:
NSF-PAR ID:
10372876
Journal Name:
The Astrophysical Journal
Volume:
937
Issue:
2
Page Range or eLocation-ID:
Article No. 112
ISSN:
0004-637X
Publisher:
DOI PREFIX: 10.3847
National Science Foundation
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