Advective accretion flow properties around rotating black holes - application to GRO J1655-40

TL;DR

This study models viscous accretion flows around rotating black holes, analyzing mass outflows and QPO frequencies, and applies the model to explain high-frequency QPOs observed in GRO J1655-40, constraining black hole spin.

Contribution

It provides a self-consistent calculation of inflow-outflow solutions including viscosity and applies the model to explain observed HFQPOs in GRO J1655-40, constraining black hole spin parameters.

Findings

Mass outflow rates decrease with higher viscosity.

Maximum QPO frequency increases with black hole spin.

Model constrains black hole spin based on observed HFQPOs.

Abstract

We examine the properties of the viscous dissipative accretion flow around rotating black holes in presence of mass loss. Considering thin disc approximation, we self-consistently calculate the inflow-outflow solutions and observe that the mass outflow rates decreases with the increase of viscosity parameter ($\alpha$). Further, we carry out the model calculation of Quasi-periodic Oscillation frequency ($\nu_{\rm QPO}$) that is frequently observed in black hole sources and observe that $\nu^{\rm max}_{\rm QPO}$ increases with the increase of black hole spin ($a_k$). Then, we employ our model in order to explain the High Frequency Quasi-periodic Oscillations (HFQPOs) observed in black hole source GRO J1655-40. While doing this, we attempt to constrain the range of $a_k$ based on observed HFQPOs ($\sim$ 300 Hz and $\sim$ 450 Hz) for the black hole source GRO J1655-40.