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Properties of Massive Rotating Protoneutron Stars with Hyperons: Structure and Universality

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 نشر من قبل Prasanta Char
 تاريخ النشر 2018
  مجال البحث فيزياء
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In this work, we study the properties and structure of a massive and rapidly rotating protoneutron star (PNS) with hyperon content. We follow several stages of quasi-stationary evolution in an approximate way at four discrete steps. We use a density-dependent (DD) relativistic mean field theory (RMF) model and calculate different quantities such as mass, equatorial radius, moment of inertia, and quadrupole moment to get different rotating configurations upto the mass-shedding limit. We study the effect of the appearance of $Lambda$, the lightest of all hyperons, on each of the evolutionary stages of the PNS. We also check its sensitivity to the inclusion of $phi$ vector meson as a mediator of $Lambda-Lambda$ interaction in detail. Finally, we investigate the universal relations between moment of inertia and compactness in the context of a hot and young compact object.

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