Eur. Phys. J. A (2016) 52: 290
https://doi.org/10.1140/epja/i2016-16290-y

Regular Article - Theoretical Physics

Neutrino diffusion in the pasta phase matter within the Thomas-Fermi approach

¹ Departamento de Fısica, CFM, Universidade Federal de Santa Catarina, CP. 476, CEP 88040-900, Florianópolis - SC, Brazil
² CFisUC, Department of Physics, University of Coimbra, P3004-516, Coimbra, Portugal

^* e-mail: ricardo.marinelli@ufsc.br

Received: 29 February 2016
Accepted: 10 August 2016
Published online: 21 September 2016

Abstract

The behaviour and properties of neutrinos in non-uniform nuclear matter, surrounded by electrons and other neutrinos are studied in the protoneutron star early stage characterized by trapped neutrinos. The nuclear matter itself is modelled by a relativistic mean-field approach, and models with both constant couplings and density-dependent couplings are considered. The so-called nuclear pasta phases at sub-saturation densities, described using the Thomas-Fermi approximation and solved in a Wigner-Seitz cell, are included in the calculation. We obtain the neutrino total cross section and mean free path, taking into account scattering and absorption processes and we compare the final results obtained with different parametrizations. The solution for this problem is important for the understanding of neutrino diffusion in a newly born neutron star after a supernovae explosion. It is shown that the pasta phase will increase the neutrino mean free path by as much as an order of magnitude, therefore contributing for shorter emission time-scales.