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arXiv · 2201.08726

Quark stars with 2.6 $M_\odot$ in a non-minimal geometry-matter coupling theory of gravity

G. A. Carvalho·R. Lobato·P. H. R. S. Moraes·D. Deb·M. Malheiro
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Abstract

This work analyses the hydrostatic equilibrium configurations of strange stars in a non-minimal geometry-matter coupling (GMC) theory of gravity. Those stars are made of strange quark matter, whose distribution is governed by the MIT equation of state. The non-minimal GMC theory is described by the following gravitational action: $f(R,L)=R/2+L+\sigma RL$, where $R$ represents the curvature scalar, $L$ is the matter Lagrangian density, and $\sigma$ is the coupling parameter. When considering this theory, the strange stars become larger and more massive. In particular, when $\sigma=50$ km$^2$, the theory can achieve the 2.6 $M_\odot$, which is suitable for describing the pulsars PSR J2215+5135 and PSR J1614-2230, and the mass of the secondary object in the GW190814 event. The 2.6 $M_\odot$ is a value hardly achievable in General Relativity even considering fast rotation effects, and is also compatible with the mass of PSR J0952-0607 ($M = 2.35 \pm 0.17 ~M_\odot$), the heaviest and fastest pulsar in the disk of the Milky Way, recently measured, supporting the possible existence of strange quark matter in its composition. The non-minimal GMC theory can also give feasible results to describe the macroscopical features of strange star candidates.

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BibTeXRIS

G. A. Carvalho, R. Lobato, P. H. R. S. Moraes, D. Deb, M. Malheiro. 2022-01-21. Quark stars with 2.6 $M_\odot$ in a non-minimal geometry-matter coupling theory of gravity. https://doi.org/10.1140/epjc/s10052-022-11058-6

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