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Radial Modes of Neutron Stars with a Quark Core

P. K. Sahu·G. F. Burgio·M. Baldo
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Abstract

We make a first calculation of eigenfrequencies of radial pulsations of neutron stars with quark cores in a general relativistic formalism given by Chandrasekhar. The equations of state (EOS) used to estimate such eigenfrequencies have been derived by taking proper care of the hadron-quark phase transition. The hadronic EOS's have been obtained in the framework of the Brueckner-Hartree-Fock and relativistic mean field theories, whereas the quark EOS has been derived within the MIT bag model. We find that the periods of oscillations of neutron stars with a quark core show a kink, which is associated with the presence of a mixed phase region. Also, oscillation periods show significant differences between ordinary neutron stars and neutron stars with dynamical quark phases.

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P. K. Sahu, G. F. Burgio, M. Baldo. 2001-11-21. Radial Modes of Neutron Stars with a Quark Core. https://doi.org/10.1086/339510

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