Strange stars in Krori–Barua spacetime under f(R,T) gravity

• Published in: Annals of physics Vol. 401; pp. 1 - 20
• Main Authors: Biswas, Suparna, Ghosh, Shounak, Ray, Saibal, Rahaman, Farook, Guha, B.K.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.02.2019
• Subjects: ANISOTROPY; ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BAG MODEL; CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; COUPLING CONSTANTS; EQUATIONS OF STATE; Exact solution; General relativity; GENERAL RELATIVITY THEORY; GEOMETRY; GRAVITATION; Krori–Barua spacetime; MATTER; METRICS; MEV RANGE; S QUARKS; SINGULARITY; SPACE-TIME; STARS; Strange star; General relativity; Strange star; Krori–Barua spacetime; Exact solution
• ISSN: 0003-4916; 1096-035X
• DOI: 10.1016/j.aop.2018.12.004

In the present work, we study about highly dense compact stars which are made of quarks, specially strange quarks, adopting the Krori–Barua (KB) (Krori and Barua, 1975) metric in the framework of f(R,T) gravity. The equation of state (EOS) of a strange star can be represented by the MIT bag model as pr(r)=13[ρ(r)−4Bg] where Bg is the bag constant, arises due to the quark pressure. Main motive behind our study is to find out singularity free and physically acceptable solutions for different features of strange stars. Here we also investigate the effect of alternative gravity in the formation of strange stars. We find that our model is consistent with various energy conditions and also satisfies Herrera’s cracking condition, TOV equation, static stability criteria of Harrison–Zel′dovich–Novikov etc. The value of the adiabatic indices as well as the EOS parameters re-establishes the acceptability of our model. Here in detail we have studied specifically three different strange star candidates, viz. PSRJ16142230,VelaX−1 and CenX−3. As a whole, present model fulfils all the criteria for stability. Another fascinating point we have discussed is the value of the bag constant which lies in the range (40−45) MeV/fm3. This is quite smaller than the predicted range, i.e., (55–75) MeV/fm3 (Farhi and Jaffe, 1984 [2]; Alcock et al., 1986 [3]). The presence of the constant (χ), arises due to the coupling between matter and geometry, is responsible behind this reduction in Bg value. For χ=0, we get the higher value for Bg as the above mentioned predicted range. •We study anisotropic strange star in f(R,T) gravity under Krori–Barua spacetime.•The set of solutions provides non-singular as well as stable stellar model.•Using observed values for mass and radius, we calculate different physical parameters.•The coupling constant χ, between matter and geometry, is the key factor in f(R,T) gravity.