Interface effects of strange quark matter with density dependent quark masses

TL;DR

This paper investigates the interface effects of strange quark matter using a mean-field approximation with density-dependent quark masses, revealing how confinement strength influences surface tension and curvature, and comparing results with the MRE method.

Contribution

It introduces a model incorporating density-dependent quark masses and compares interface property predictions with the MRE approach, highlighting discrepancies and necessary modifications.

Findings

Surface tension increases with confinement strength.

MRE overestimates surface tension compared to MFA.

Modified density of states improves MRE accuracy.

Abstract

We study the interface effects in strangelets adopting mean-field approximation (MFA). Based on an equivparticle model, the linear confinement and leading-order perturbative interactions are included with density-dependent quark masses. By increasing the confinement strength, the surface tension and curvature term of strange quark matter (SQM) become larger, while the perturbative interaction does the opposite. For those parameters constrained according to the 2$M_\odot$ strange star, the surface tension is $\sim$2.4 MeV/fm${}^2$, while unstable SQM indicates a slightly larger surface tension. The obtained results are then compared with those predicted by the multiple reflection expansion (MRE) method. In contrast to the bag model case, it is found that MRE method overestimates the surface tension and underestimates the curvature term. To reproduce our results, the density of states in the MRE approach should be modified by proper damping factors.