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

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 existence of strange 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 /µ 2 in the range of 4.58 GeV −2 ≤ g 2 /µ 2 ≤ 9.32 GeV −2 , and that the parameters D and C of the QMDD model are restricted to 158.3 MeV≤ D 1/2 ≤ 181.2 MeV and −0.65 ≤ C ≤ −0.12. It is found that the largest possible maximum mass of a strange star obtained with the QMDD model is 2.42 M ⊙ , and that the secondary component of GW190814 with a mass of 2.59 +0.08 −0.09 M ⊙ could not be a static strange star. We also find that for the 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, GW170817 and PSR J0030+0451 simultaneously. However, for the mass and radius given by Miller et al., no such parameter space exist.