Are There Black Hole Symbiotic X-Ray Binaries?

• Published in: The Astrophysical journal Vol. 977; no. 1; pp. 95 - 104
• Main Authors: Deng, Zhu-Ling, Li, Xiang-Dong
• Format: Journal Article
• Language: English
• Published: Philadelphia The American Astronomical Society 01.12.2024; IOP Publishing
• Subjects: Binary stars; Black holes; Galaxies; Low-mass x-ray binary stars; Neutron stars; Red giant stars; Stellar mass black holes; Supernova; Wind speed; Wind velocities; X ray binaries; X ray stars; X-ray astronomy; X-rays
• ISSN: 0004-637X; 1538-4357
• DOI: 10.3847/1538-4357/ad90ab

While there are over a dozen known neutron star (NS) symbiotic X-ray binaries (SyXBs) in the Galaxy, no SyXBs containing a black hole (BH) have been detected. We address this problem by incorporating binary population synthesis and the accretion properties of BHs fed by the wind from red giant companions. We investigate the impact of different supernova mechanisms, kick velocity distributions, and wind velocities on the formation of both NS and BH SyXBs. Our simulations show that the number of BH SyXBs is at most one-sixth of that of NS SyXBs in the Galaxy provided that the common envelope efficiency parameter α ∼ 0.3–5, and less than ∼10 BH SyXBs could be detectable in X-ray, considering their low radiation efficiencies. These findings indicate a scarcity of BH SyXBs in the Galaxy.