Quark-nova remnants^*

II. The degenerate torus case with applications to AXPs

Department of Physics and Astronomy, University of Calgary, 2500 University Drive NW, Calgary, Alberta, T2N 1N4, Canada e-mail: ouyed@phas.ucalgary.ca

Received: 6 March 2007
Accepted: 11 September 2007

Abstract

In the first paper of this series we explored the case where a quark-nova ejecta forms a degenerate shell, supported by the star's magnetic field. Herein, we consider the case where the ejecta has sufficient angular momentum to form a torus, and we show that the density and temperature of the torus are such that it will remain degenerate throughout it's lifetime. We go on to discuss the evolution of such a torus and apply it to AXPs, specifically 1E2259+586 and 4U0142+615. As it turns out, using our model we can account for many of the observations of these objects including the quiescent phase luminosity, and blackbody temperatures during both quiescence and bursting. Furthermore, for 1E2259+586 our model explains the steep and slow decay components seen in the burst lightcurve, as well as the rotation period glitches and enhanced spin-down rate. We also estimate the mass of the degenerate torus to be of the order of , and speculate that the observed optical/infrared emission from 4U0142+615 might be a signature of the thin degenerate torus we describe here.