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arXiv · 2101.00415

Distinct Classes of Compact Stars Based On Geometrically Deduced Equations of State

A. C. Khunt·V. O. Thomas·P. C. Vinodkumar
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Abstract

We have computed the properties of compact objects like neutron stars based on equation of state (EOS) deduced from a core-envelope model of superdense stars. Such superdense stars have been studied by solving the Einstein's equation based on pseudo-spheroidal and spherically symmetric space-time geometry. The computed star properties are compared with those obtained based on nuclear matter equations of state. From the mass-radius ($M-R$) relationship obtained here, we are able to classify compact stars in three categories: (i) highly compact self -bound stars that represents exotic matter compositions with radius lying below 9 km (ii) normal neutron stars with radius between 9 to 12 km and (iii) soft matter neutron stars having radius lying between 12 to 20 km. Other properties such as Keplerian frequency, surface gravity and surface gravitational redshift are also computed for all the three types. The present work would be useful for the study of highly compact neutron like stars having exotic matter compositions.

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A. C. Khunt, V. O. Thomas, P. C. Vinodkumar. 2021-01-02. Distinct Classes of Compact Stars Based On Geometrically Deduced Equations of State. https://doi.org/10.1142/s0218271821500292

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