Direct Urca Process in a Neutron Star Mantle

M. E. Gusakov; D. G. Yakovlev; P. Haensel; O. Y. Gnedin

doi:10.1051/0004-6361:20040288

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arXiv · astro-ph/0404165

Direct Urca Process in a Neutron Star Mantle

M. E. Gusakov·D. G. Yakovlev·P. Haensel·O. Y. Gnedin

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Abstract

We show that the direct Urca process of neutrino emission is allowed in two possible phases of nonspherical nuclei (inverse cylinders and inverse spheres) in the mantle of a neutron star near the crust-core interface. The process is open because neutrons and protons move in a periodic potential created by inhomogeneous nuclear structures. In this way the nucleons acquire large quasimomenta needed to satisfy momentum-conservation in the neutrino reaction. The appropriate neutrino emissivity in a nonsuperfluid matter is about 2--3 orders of magnitude higher than the emissivity of the modified Urca process in the stellar core. The process may noticeably accelerate the cooling of low-mass neutron stars.

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M. E. Gusakov, D. G. Yakovlev, P. Haensel, O. Y. Gnedin. 2004-04-07. Direct Urca Process in a Neutron Star Mantle. https://doi.org/10.1051/0004-6361%3A20040288

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