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Rearrangement of the Fermi Surface of Dense Neutron Matter and Direct Urca Cooling of Neutron Stars

D. N. Voskresensky·V. A. Khodel·M. V. Zverev·J. W. Clark
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Abstract

It is proposed that a rearrangement of single-particle degrees of freedom may occur in a portion of the quantum fluid interior of a neutron star. Such a rearrangement is associated with the pronounced softening of the spin-isospin collective mode which, under increasing density, leads to pion condensation. Arguments and estimates based on fundamental relations of many-body theory show that one realization of this phenomenon could produce very rapid cooling of the star via a direct nucelon Urca process displaying a $T^5$ dependence on temperature.

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D. N. Voskresensky, V. A. Khodel, M. V. Zverev, J. W. Clark. 2000-03-13. Rearrangement of the Fermi Surface of Dense Neutron Matter and Direct Urca Cooling of Neutron Stars. https://doi.org/10.1086/312607

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