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arXiv · 1909.07579

Structural Properties of Rotating Hybrid Compact Stars with Color-Flavour-Locked Quarks Matter core and its Tidal Deformability

Suman Thakur·Shashi K Dhiman
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Abstract

We investigate the possible sequels, for the hybrid compact stars consisting of nucleons, hyperons and three flavour color-flavor-locked quarks phase under global neutrality and chemical equilibrium conditions. The hadron equations of state are computed within the framework of energy density functionals based on the relativistic mean field theory by employing two different model parameterizations. The quarks matter phase of equation of state is computed by using Quarks Quasiparticle model derived from a non-relativistic energy density-functional approach. A plausible set of hybrid equations of state for superdense hadron-quarks matter is obtained and, which satisfies the constraints provided by bulk nuclear matter, the observational data of frequencies and maximum Gravitational mass 2$M_\odot$ with their extracted radii, Keplerian limits, secular axisymmetric instability and limits of tidal deformabilities from GW170817 binary neutron stars (BNS) merger. We obtained structural properties of nonrotating and rotating compact stars, the evolutionary sequences with constant baryonic mass star spinning down by electromagnetic and gravitational radiations and, discuss the issues relating to phase transition from hadrons to quarks matter phase. The internal structure of rotating star with observed spin down frequencies, exhibiting shrinkage of soft quarks core of compact stars are discussed for constant baryonic mass. We present the theoretically computed limits of radii for the spin down configurations of hybrid stars corresponding to the recently observed millisecond pulsars. We also present and discuss the calculated results for tidal deformability, $Λ$ and tidal parameters $Λ_1$, $Λ_2$ of non spining hybrid star which are consistent with the waveform model analysis of GW170817 BNS.

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Suman Thakur, Shashi K Dhiman. 2019-09-17. Structural Properties of Rotating Hybrid Compact Stars with Color-Flavour-Locked Quarks Matter core and its Tidal Deformability. https://arxiv.org/abs/1909.07579

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