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arXiv · 1506.00984

Hadron-Quark Crossover and Hot Neutron Stars at Birth

Kota Masuda·Tetsuo Hatsuda·Tatsuyuki Takatsuka
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Abstract

We construct a new isentropic equation of state (EOS) at finite temperature "CRover" on the basis of the hadron-quark crossover at high density. By using the new EOS, we study the structure of hot neutron stars at birth with the typical lepton fraction ($Y_l=0.3-0.4$) and the typical entropy per baryon ($S=1-2$). Due to the gradual appearance of quark degrees of freedom at high density, the temperature T and the baryon density at the center of the hot neutron stars with the hadron-quark crossover are found to be smaller than those without the crossover by a factor of 2 or more. Typical energy release due to the contraction of a hot neutron star to a cold neutron star with 1.4 solarmass is shown to be about 0.04 solarmass with the spin-up rate about 14%.

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Kota Masuda, Tetsuo Hatsuda, Tatsuyuki Takatsuka. 2015-06-02. Hadron-Quark Crossover and Hot Neutron Stars at Birth. https://doi.org/10.1093/ptep%2Fptv187

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