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arXiv · 0812.0102

Chiral effective field theory calculations of neutrino processes in dense matter

S. Bacca·K. Hally·C. J. Pethick·A. Schwenk
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Abstract

We calculate neutrino processes involving two nucleons at subnuclear densities using chiral effective field theory. Shorter-range noncentral forces reduce the neutrino rates significantly compared with the one-pion exchange approximation currently used in supernova simulations. For densities rho < 10^{14} g cm^{-3}, we find that neutrino rates are well constrained by nuclear interactions and nucleon-nucleon scattering data. As an application, we calculate the mean-square energy transfer in scattering of a neutrino from nucleons and find that collision processes and spin-dependent mean-field effects dominate over the energy transfer due to nucleon recoil.

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S. Bacca, K. Hally, C. J. Pethick, A. Schwenk. 2009-09-10. Chiral effective field theory calculations of neutrino processes in dense matter. https://doi.org/10.1103/physrevc.80.032802

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