Linear and Nonlinear Dynamics of Relativistic Tori

TL;DR

This paper investigates the dynamics of relativistic tori around black holes using simulations, revealing their stability properties, oscillation behaviors, and potential gravitational wave signals.

Contribution

It provides the first detailed simulation-based analysis of relativistic torus oscillations and their gravitational wave emissions in the context of black hole accretion.

Findings

Oscillations cause quasi-periodic accretion bursts

Oscillations produce strong gravitational wave signals

Tori can be unstable or stable depending on perturbations

Abstract

I present results of two-dimensional general relativistic hydrodynamical simulations of constant specific angular momentum tori orbiting around a Schwarzschild black hole. After introducing axisymmetric perturbations, these objects either become unstable to the runaway instability or respond with regular oscillations. The latter, in particular, are responsible for quasi-periodic bursts of accretion onto the black hole as well as for the emission of intense gravitational radiation, with signal-to-noise ratios at the detector which are comparable or even larger than the typical ones expected in stellar-core collapse.