Cooling and Heating Solid Quark Stars

TL;DR

This paper proposes a phenomenological model of solid quark stars to explain their thermal X-ray emissions, emphasizing the role of reheating by plasma bombardment and suggesting that some observed X-ray sources could be solid quark stars.

Contribution

It introduces a new model for solid quark stars that accounts for their thermal emissions and long-term heating mechanisms, differing from traditional neutron star models.

Findings

Solid quark stars have small heat capacity, leading to rapid cooling after formation.

Reheating by plasma bombardment can sustain long-term soft X-ray emission.

Some X-ray pulsars and dim X-ray sources could be solid quark stars.

Abstract

We present here a phenomenological solid quark star pulsar model to interpret the observed thermal X-ray emission of isolated pulsars. The heat capacity for solid quark stars was found to be quite small, so that the residual internal stellar heat gained at the birth of the star could be dissipated in an extremely short timescale. However, the bombardment induced by backflowing plasma at the poles of solid quark stars would get the stars be reheated, so that long term soft X-ray emission can be sustained. Such a scenario could be used for those X-ray pulsars with significant magnetospheric activities, and their cooling processes would thus be established. Dim X-ray isolated neutron stars (XDINs) as well as compact central objects (CCOs) have been observed with dominant soft X-ray radiation combined with little magnetospheric manifestations. Such sources could be solid quark stars accreting in the propeller regime.