There are few observed highmass Xray 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 gravitationalwave (GW) observations. We investigate the role that Xray 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
 Publication Date:
 NSFPAR ID:
 10132216
 Journal Name:
 Monthly Notices of the Royal Astronomical Society
 ISSN:
 00358711
 Sponsoring Org:
 National Science Foundation
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