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arXiv · 1807.06569

In-medium enhancement of the modified Urca neutrino reaction rates

P. S. Shternin·M. Baldo·P. Haensel
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Abstract

We calculate modified Urca neutrino emission rates in the dense nuclear matter in neutron star cores. We find that these rates are strongly enhanced in the beta-stable matter in regions of the core close to the direct Urca process threshold. This enhancement can be tracked to the use of the in-medium nucleon spectrum in the virtual nucleon propagator. We describe the in-medium nucleon scattering in the non-relativistic Bruckner-Hartree-Fock framework taking into account two-body as well as the effective three-body forces, although the proposed enhancement does not rely on a particular way of the nucleon interaction treatment. Finally we suggest a simple approximate expression for the emissivity of the n-branch of the modified Urca process that can be used in the neutron stars cooling simulations with any nucleon equation of state of dense matter.

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P. S. Shternin, M. Baldo, P. Haensel. 2018-09-18. In-medium enhancement of the modified Urca neutrino reaction rates. https://doi.org/10.1016/j.physletb.2018.09.035

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