$R^2$-gravity quark stars from perturbative QCD

TL;DR

This paper explores how quadratic gravity modifications influence the structure and stability of quark stars using perturbative QCD equations of state, revealing significant effects on their mass and radius.

Contribution

It introduces a study of quark stars within $f(R)= R+ eta R^2$ gravity using perturbative QCD, highlighting the impact of the free parameter on stellar properties.

Findings

Large parameter ranges affect star mass and radius.

Modified gravity slightly influences binding energies.

Stability against baryon evaporation remains largely intact.

Abstract

We investigate the structure of quark stars in the framework of $f(R)= R+ \alpha R^2$ gravity using an equation of state for cold quark matter obtained from perturbative QCD, parametrized only by the renormalization scale. We show that a considerably large range of the free parameter $\alpha$, within and even beyond the constraints previously reported in the literature, yield non-negligible modifications in the mass and radius of stars with large central mass densities. Besides, their stability against baryon evaporation is analyzed through the behavior of the associated total binding energies for which we show that these energies are slightly affected by the modified gravity term in the regime of high proper (baryon) masses.