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arXiv · 2212.04885

Rapidly rotating neutron stars with realistic nuclear matter equation of state

Balázs Kacskovics·Dániel Barta·Mátyás Zsolt Vasúth
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Abstract

We performed a comparison of three different numerical codes for constructing equilibrium models; (I) a code for static equilibrium configurations, (II) an implementation of the Hartle--Thorne slow-rotation approximation, (III) a numerical solution of the full Einstein equations by \texttt{LORENE}. We aimed to construct sequences of uniformly rotating configurations at various rotation frequencies up to the Keplerian frequency for a hybrid hadronic--quark matter EOS where a smooth transition is provided between two separate phases. We investigated the difference of between the results computed by the implementation of Hartle--Thorne slow-rotation approximation and by \texttt{LORENE/nrotstar}, respectively. We have conclude that the codes can the difference between the slow rotating and the fast-rotating approach increase exponentially, reaching 6.67% for the maximal mass configuration rotating at the Keplerian frequency.

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Balázs Kacskovics, Dániel Barta, Mátyás Zsolt Vasúth. 2022-12-09. Rapidly rotating neutron stars with realistic nuclear matter equation of state. https://doi.org/10.1002/asna.20220109

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