2006/11/10 by Sergei Nayakshin, R. Sunyaev, Rashid Sunyaev
Physics and Astronomy · #Accretion (finance) #Active galactic nucleus #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Astrophysics and Cosmic Phenomena #Black hole (networking) #Compact star #Galactic Center #Galaxies: Formation, Evolution, Phenomena #Galaxy #Intermediate-mass black hole #Mass segregation #Neutron star #Physics #Star cluster #Star formation #Stars #Stellar mass #Supermassive black hole #astro-ph
paper · pdf · doi:10.1111/j.1365-2966.2007.11725.x
published as Mon.Not.Roy.Astron.Soc.377:1647-1651,2007 · submitted to MNRAS; 5 pages
arxiv created 2006/11/10 · openalex publication_date 2007/05/26 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Compact remnants – stellar mass black holes and neutron stars formed in the inner few parsec of galactic centres are predicted to sink into the central parsec due to dynamical friction on low-mass stars, forming a high concentration cusp. Same physical region may also contain very high-density molecular clouds and accretion discs that are needed to fuel supermassive black hole (SMBH) activity. Here we estimate gas capture rates on to the cusp of stellar remnants, and the resulting X-ray luminosity, as a function of the accretion disc mass. At low disc masses, most compact objects are too dim to be observable, whereas in the high disc case most of them are accreting at their Eddington rates. We find that for low accretion disc masses, compact remnant cusps may be more luminous than the central SMBHs. This ‘diffuse’ emission may be of importance for local moderately bright active galactic nuclei (AGNs), especially low-luminosity AGNs. We also briefly discuss how this expected emission can be used to put constraints on the black hole cusp near our Galactic Centre.