2004/09/29 by Takayuki R. Saitoh, Keiichi Wada · 20 citations
Physics and Astronomy · #Accretion (finance) #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Astrophysics and Star Formation Studies #Black hole (networking) #Galactic halo #Galaxies: Formation, Evolution, Phenomena #Galaxy #Galaxy formation and evolution #Halo #Interacting galaxy #Physics #Spiral galaxy #Supermassive black hole #astro-ph
paper · pdf · doi:10.1086/426119
published in The Astrophysical Journal 615(2), L93-L96 (IOP Publishing) · 4 pages, 4 figures, Accepted for publication in ApJL
arxiv created 2004/09/29 · openalex publication_date 2004/10/06 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
Using high-resolution N -body/smoothed particle hydrodynamics simulations with 2 × 10 6 particles, we investigate the evolution of stellar and gaseous galactic cores during the hierarchical formation of a spiral galaxy. We find that the galactic core ( r < 300 pc) coevolves with the host galaxy. The average mass ratio between the baryonic core and the halo is nearly constant, ~0.04 from z ~ 10 to z ~ 2. However, there are several "rapid-growing phases" during the evolution, in which the rate of mass accretion to the central subkiloparsec region is 10 times higher (~1 M ☉ yr pc -1 ) than the average accretion rate. The rapid growth of the inner core is associated with the major merger events with a time delay. We also find that the spin axis of the gas core frequently changes. As a result, the angular momentum vector of the central part of the galaxy is independent of the rotation of the outer part. Our results suggest that if a constant fraction of the baryonic mass in the central several 100 pc of a galaxy is converted into a massive black hole, the black hole mass should correlate with the total mass of the galaxies.