Accretion onto a black hole in a string cloud background

Abstract

We examine the accretion process onto the black hole with a string cloud background, where the horizon of the black hole has an enlarged radius $r_H=2M/(1-\alpha )$, due to the string cloud parameter $\alpha (0\le \alpha <1)$. The problem of stationary, spherically symmetric accretion of a polytropic fluid is analysed to obtain an analytic solution for such a perturbation. Generalised expressions for the accretion rate $\dot{M}$, critical radius $r_s$, and other flow parameters are found. The accretion rate $\dot{M}$ is an explicit function of the black hole mass $M$, as well as the gas boundary conditions and the string cloud parameter $\alpha$. We also find the gas compression ratios and temperature profiles below the accretion radius and at the event horizon. It is shown that the mass accretion rate, for both the relativistic and the non-relativistic fluid by a black hole in the string cloud model, increases with increase in $\alpha$.

9 pages, To appear in Phys. Rev. D

References in corpus (3)

• Charged Black Holes in Phantom Cosmology
• Cloud of strings for radiating black holes in Lovelock gravity
• Phantom Accretion by Five Dimensional Charged Black Hole

Cited by in corpus (6)

• Quantum Corrections to the Accretion onto a Schwarzschild Black Hole in the Background of Quintessence
• Accretion on Reissner-Nordstrom-(anti)-de Sitter Black Hole with Global Monopole
• Adiabatic accretion onto black holes in Einstein-Maxwell-scalar theory
• Accretion on High Derivative Asymptotically Safe Black Holes
• Matter Accretion onto a Conformal Gravity Black Hole
• Accretion of matter and spectra of Binary X-ray sources in Massive Gravity