Viscous Dark Energy Accretion Activities : Sonic Speed, Angular Momentum and Mach Number Studies

TL;DR

This paper investigates viscous dark energy accretion onto black holes, analyzing sonic speed, angular momentum, and Mach number variations, revealing that viscosity and black hole spin weaken the accretion process.

Contribution

It introduces a detailed study of viscous dark energy accretion using modified Chaplygin gas, highlighting the effects of viscosity and black hole spin on accretion dynamics.

Findings

Sonic speed decreases closer to the black hole, with a threshold drop due to viscosity.

Black hole spin increases the rate of sonic speed decline.

Accretion Mach number increases inward, indicating stronger inflow near the black hole.

Abstract

In this present article, we study different accretion properties regarding viscous accretion of dark energy. Modified Chaplygin gas is chosen as the dark energy candidate. Viscosity is encountered with the help of Shakura-Sunyaev viscosity parameter. We study sonic speed vs radial distance curves. We compare between adiabatic and dark energy dominated cases and follow that sonic speed falls as we go nearer to the central gravitating object. As viscosity is imposed, a threshold drop in accretion sonic speed is followed. Average rate of fall in accretion sonic speed is increased with black hole's spin. This is signifying that this kind of accretion is weakening the overall matter/energy infall. Specific angular momentum to Keplerian angular momentum ratio is found to fall as we go far from the black hole. Accretion Mach number turns high as we go towards the inner region and high wind Mach number is not allowed as we are going out. Combining, we conclude that the system weakens the feeding process of accretion.