Direct Urca Process in a Neutron Star Mantle
Astrophysics
2009-11-10 v1
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.
Cite
@article{arxiv.astro-ph/0404165,
title = {Direct Urca Process in a Neutron Star Mantle},
author = {M. E. Gusakov and D. G. Yakovlev and P. Haensel and O. Y. Gnedin},
journal= {arXiv preprint arXiv:astro-ph/0404165},
year = {2009}
}
Comments
7 pages, 3 figures, submitted to A&A