Constraints from compact star observations on non-Newtonian gravity in strange stars based on a density dependent quark mass model

TL;DR

This study explores how non-Newtonian gravity influences strange star properties within a density-dependent quark mass model, constraining model parameters using recent astrophysical observations and ruling out certain strange star configurations.

Contribution

It introduces constraints on non-Newtonian gravity parameters and QMDD model parameters based on recent pulsar and gravitational wave data, highlighting the impact of modified gravity on strange star viability.

Findings

Strange stars are incompatible with observations if non-Newtonian gravity is ignored.

Allowed non-Newtonian gravity parameters range from 4.58 to 9.32 GeV$^{-2}$.

Maximum strange star mass with QMDD model is 2.42 solar masses.

Abstract

Using a density dependent quark mass (QMDD) model for strange quark matter, we investigate the effects of non-Newtonian gravity on the properties of strange stars and constrain the parameters of the QMDD model by employing the mass of PSR J0740+6620 and the tidal deformability of GW170817. We find that for QMDD model these mass and tidal deformability observations would rule out the existenceof str ange stars if non-Newtonian gravity effects are ignored. For the current quark masses of $m_{u0}=2.16$ MeV, $m_{d0}=4.67$ MeV, and $m_{s0}=93$ MeV, we find that a strange star can exist for values of the non-Newtonian gravity parameter $g^{2}/\mu^{2}$ in the range of 4.58 GeV$^{-2}\leq g^{2}/\mu^{2}\leq$ 9.32 GeV$^{-2}$, and that the parameters $D$ and $C$ of the QMDD modelare restricted to 158.3 MeV$\leq D^{1/2}\leq$ 181.2 MeV and $-0.65\leq C \leq -0.12$. It is found that the largest possible maximum mass of a strange star obtained with the QMDD model is $2.42 \, M_{\odot}$, and that the secondary componentof GW190814 with a mass of 2.59_{-0.09}^{+0.08}\, M_{\dot} could not be a static strange star. We also find that forthe mass and radius of PSR J0030+0451 given by Riley et al. through the analysis of observational data of NICER, there exists a very tiny allowed parameter space for which strange stars computed for the QMDD model agree with the observations of PSR J0740+6620, GW17 0817 and PSR J0030+0451 simultaneously. However, for the mass and radius given by Miller et al., no such parameter space exist.