Thermal Relaxation and Cooling of Quark Stars with a Strangelet Crust

TL;DR

This paper investigates how different crust compositions, including strangelet crusts, affect the thermal relaxation and cooling times of quark stars, considering also the impact of color superconductivity in the core.

Contribution

It introduces models of quark stars with strangelet crusts and analyzes their thermal relaxation, highlighting the significant differences caused by crust composition and superconductivity effects.

Findings

Strangelet crusts alter the thermal relaxation times of quark stars.

Color superconductivity influences the cooling behavior of the quark core.

Strangelet crusts lead to distinct cooling signatures compared to nuclear matter crusts.

Abstract

In this article, we explore the cooling of isolated quark stars. These objects are structured of a homogeneous quark matter core and crusted by matter. To do this, we adopt two kinds of crust: (i) a crust made of purely nuclear matter following the Baym-Pethick-Sutherland (BPS) equation of state (EoS) and (ii) a crust made of nuggets of strange quark matter (strangelets). Both models have the same quark matter core described by the MIT bag model EoS. Our main purpose is to quantify the effects of a strangelet crust on the cooling and relaxation times of these strange stars. We also perform a thorough study of the thermal relaxation of quark stars, in which we have found that objects with a strangelet crust have a significantly different thermal relaxation time. Our study also includes the possible effects of color superconductivity in the quark core.