Supernovae-induced accretion and star formation in the inner kiloparsec of a gaseous disk

TL;DR

This paper explores how supernovae influence gas accretion and star formation in the central kiloparsec of a galaxy, revealing a self-regulating cycle that impacts black hole growth and bulge formation.

Contribution

It demonstrates that supernovae can drive accretion and star formation in galactic centers, providing a mechanism consistent with observed black hole-bulge mass ratios.

Findings

Supernovae induce accretion rates of 0.1-1 M_Sun/year.

Star formation rates of 10-100 M_Sun/year are triggered.

The supernova activity cycle is self-regulating.

Abstract

We consider the effects of supernovae (SNe) on accretion and star formation in a massive gaseous disk in a large primeval galaxy. The gaseous disk we envisage, roughly 1 kiloparsec (kpc) in size with >~ 10^8 M_Sun of gas, could have formed as a result of galaxy mergers where tidal interactions removed angular momentum from gas at larger radius and thereby concentrated it within the central ~ 1 kpc region. We find that SNe lead to accretion in the disk at a rate of roughly 0.1 - 1 M_Sun per year and induce star formation at a rate of ~ 10 - 100 M_Sun per year which contributes to the formation of a bulge; a part of the stellar velocity dispersion is due to the speed of SNa shells from which stars are formed and a part due to the repeated action of the stochastic gravitational field of the network of SNa remnants on stars. The rate of SNe in the inner kpc is shown to be self- regulating, and it cycles through phases of low and high activity. The supernova-assisted accretion transports gas from about one kpc to within a few pc of the center. If this accretion were to continue down to the central black hole (BH) then the resulting ratio of BH mass to the stellar mass in the bulge would be of order ~ 10^-2 - 10^-3, in line with the observed Magorrian relation.