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Relativistic strange stars in Tolman-Kuchowicz spacetime

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 نشر من قبل Saibal Ray
 تاريخ النشر 2019
  مجال البحث فيزياء
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In this article we propose a relativistic model of a static spherically symmetric anisotropic strange star with the help of Tolman-Kuchowicz (TK) metric potentials [Tolman, Phys. Rev. {bf55}, 364 (1939) and Kuchowicz, Acta Phys. Pol. {bf33}, 541 (1968)]. The form of the potentials are $lambda(r)=ln(1+ar^2+br^4)$ and $ u(r)=Br^2+2ln C$ where $a$, $b$, $B$ and $C$ are constants which we have to evaluate using boundary conditions. We also consider the simplest form of the phenomenological MIT bag equation of state (EOS) to represent the strange quark matter (SQM) distribution inside the stellar system. Here, the radial pressure $p_r$ relates with the density profile $rho$ as follows, $p_r(r)=frac{1}{3}[rho(r)-4B_g]$, where $B_g$ is the Bag constant. To check the physical acceptability and stability of the stellar system based on the obtained solutions, we have performed various physical tests. It is shown that the model satisfies all the stability criteria, including nonsingular nature of the density and pressure, implies stable nature. Here, the Bag constant for different strange star candidates are found to be $(68-70)$~MeV/{fm}$^3$ which satisfies all the acceptability criteria and remains in the experimental range.

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