2020/09/01 by Yunfeng Chen, Qingjuan Yu, Youjun Lu · 4 citations
Physics and Astronomy · #Angular momentum #Astrophysical Phenomena and Observations #Astrophysics #Astrophysics and Cosmic Phenomena #Galactic Center #Galaxies: Formation, Evolution, Phenomena #Galaxy #Order (exchange) #Physics #Star formation #Stars #Stellar mass #Tidal force #astro-ph.GA #astro-ph.HE
paper · pdf · doi:10.3847/1538-4357/aba950
published in The Astrophysical Journal 900(2), 191 (IOP Publishing) · 20 pages, 9 figures
openalex publication_date 2020/09/01 · arxiv created 2020/12/07 · arxiv updated 2020/12/08 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
Abstract Stars can be consumed (either tidally disrupted or swallowed whole) by massive black holes (MBHs) at galactic centers when they move into the vicinity of the MBHs. In this study, we investigate the rates of stellar consumption by central MBHs and their cosmic distributions, including the effects of triaxial galaxy shapes in enhancing the reservoir of low-angular-momentum stars and incorporating realistic galaxy distributions. We find that the enhancement in the stellar consumption rates due to triaxial galaxy shapes can be significant, by a factor of ∼3 for MBH mass <?CDATA MBH∼ 105?> – <?CDATA 106 M\odot ?> and up to more than one order of magnitude for <?CDATA MBH\gtrsim 108 M\odot ?> . Only for <?CDATA MBH\lesssim 107 M\odot ?> are the stellar consumption rates significantly higher in galaxies with steeper inner surface brightness profiles. The average (per galaxy) stellar consumption rates correlate with central MBH masses positively for <?CDATA MBH\gtrsim 107 M\odot ?> and negatively for <?CDATA MBH\lesssim 107 M\odot ?> . The volumetric stellar tidal disruption rates are <?CDATA ∼ 3× 10-5 yr-1 Mpc-3?> for MBHs in the mass range 10 5 – <?CDATA 108 M\odot ?> at z = 0; and the volumetric stellar consumption rates by MBHs with higher masses are <?CDATA ∼ 10-6 yr-1 Mpc-3?> , which can be the stellar tidal disruption rate if the high-mass BHs are extremely spinning Kerr BHs or the rate of being swallowed if those BHs are Schwarzschild ones. The volumetric stellar consumption rates decrease with increasing redshift, and the decrease is relatively mild for <?CDATA MBH∼ 105?> – <?CDATA 107 M\odot ?> and stronger for higher <?CDATA MBH?> . Most of the stellar tidal disruption events (TDEs) at z = 0 occur in galaxies with mass <?CDATA Mgal\lesssim 1011 M\odot ?> , and about 1%–2% of the TDEs can occur in high-mass galaxies with <?CDATA Mgal\gtrsim 1011 M\odot ?> .