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Neutrino emission in neutron stars

E. N. E. van Dalen·A. E. L. Dieperink·J. A. Tjon
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Abstract

Neutrino emissivities in a neutron star are computed for the neutrino bremsstrahlung process. In the first part the electro-weak nucleon-nucleon bremsstrahlung is calculated in free space in terms of a on-shell $T$-matrix using a generalized Low energy theorem. In the second part the emissivities are calculated in terms of the hadronic polarization at the two-loop level. Various medium effects, such as finite particle width, Pauli blocking in the $T$-matrix are considered. Compared to the pioneering work of Friman and Maxwell in terms of (anti-symmetrized) one-pion exchange the resulting emissivity is about a factor 4 smaller at saturation density.

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E. N. E. van Dalen, A. E. L. Dieperink, J. A. Tjon. 2003-03-14. Neutrino emission in neutron stars. https://doi.org/10.1103/physrevc.67.065807

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