1999/02/02 by John Magorrian, J. Magorrian, Scott Tremaine +1 · 2 citations
Engineering · Physics and Astronomy · #Astronomy and Astrophysical Research #Black hole (networking) #Dwarf galaxy #Galaxies: Formation, Evolution, Phenomena #Galaxy #Space Technology and Applications #Star formation #Stars #Stellar dynamics #Stellar mass loss #Supermassive black hole #astro-ph
paper · pdf · doi:10.1046/j.1365-8711.1999.02853.x
published as Mon.Not.Roy.Astron.Soc.309:447,1999 · 14 pages, 5 figures, 1 landscape table. Submitted to MNRAS
arxiv created 1999/02/02 · openalex publication_date 1999/10/21 · arxiv updated 2011/05/05 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/08
There is strong evidence for some kind of massive dark object in the centres of many galaxy bulges. The detection of flares from tidally disrupted stars could confirm that these objects are black holes (BHs). Here we present calculations of the stellar disruption rates in detailed dynamical models of real galaxies, taking into account the refilling of the loss cone of stars on disruptable orbits by two-body relaxation and tidal forces in non-spherical galaxies. The highest disruption rates (one star per 104 yr) occur in faint (L≲1010 L⊙) galaxies, which have steep central density cusps. More luminous galaxies are less dense and have much longer relaxation times and more massive BHs. Dwarf stars in such galaxies are swallowed whole by the BH and hence do not emit flares; giant stars could produce flares as often as every 105 yr, although the rate depends sensitively on the shape of the stellar distribution function. We discuss the possibility of detecting disruption flares in current supernova searches. The total mass of stars consumed over the lifetime of the galaxy is of the order of 106 M⊙, independent of galaxy luminosity; thus, disrupted stars may contribute significantly to the present BH mass in galaxies fainter than ∼109 L⊙.