There are few observed high-mass X-ray binaries (HMXBs) that harbor massive black holes (BHs), and none are likely to result in a binary black hole (BBH) that merges within a Hubble time; however, we know that massive merging BBHs exist from gravitational-wave (GW) observations. We investigate the role that X-ray and GW observational selection effects play in determining the properties of their respective detected binary populations. We find that, as a result of selection effects, detectable HMXBs and detectable BBHs form at different redshifts and metallicities, with detectable HMXBs forming at much lower redshifts and higher metallicities than detectable BBHs. We also find disparities in the mass distributions of these populations, with detectable merging BBH progenitors pulling to higher component masses relative to the full detectable HMXB population. Fewer than 3% of detectable HMXBs host BHs >35
This content will become publicly available on April 1, 2023
- Award ID(s):
- 1912648
- Publication Date:
- NSF-PAR ID:
- 10391494
- Journal Name:
- The Astrophysical Journal Letters
- Volume:
- 929
- Issue:
- 2
- Page Range or eLocation-ID:
- L26
- ISSN:
- 2041-8205
- Sponsoring Org:
- National Science Foundation
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