Mass-losing accretion discs around supermassive black holes

TL;DR

This paper investigates how outflows and winds influence the gravitational stability and clump formation in accretion discs around supermassive black holes, using analytical models with mass-loss and angular momentum parameters.

Contribution

It introduces a set of analytical steady-state solutions that incorporate outflow effects, revealing how mass-loss impacts the self-gravitating radius and clump mass in accretion discs.

Findings

Mass of initial clumps decreases with higher outflow mass-loss rate.

Self-gravitating radius generally increases with more outflow mass-loss.

Greater angular momentum loss by outflow leads to smaller initial clump masses.

Abstract

We study the effects of outflow/wind on the gravitational stability of accretion discs around supermassive black holes using a set of analytical steady-state solutions. Mass-loss rate by the outflow from the disc is assumed to be a power-law of the radial distance and the amount of the energy and the angular momentum which are carried away by the wind are parameterized phenomenologically. We show that the mass of the first clumps at the self-gravitating radius linearly decreases with the total mass-loss rate of the outflow. Except for the case of small viscosity and high accretion rate, generally, the self-gravitating radius increases as the amount of mass-loss by the outflow increases. Our solutions show that as more angular momentum is lost by the outflow, then reduction to the mass of the first clumps is more significant.