Spin response and neutrino mean free path in dense neutron matter

Strong magnetic fields may influence the behaviour of nuclear matter in supernova explosions and in catastrophic events involving neutron stars and might affect the properties of neutrinos emitted during the process. In this study we developed a mean field treatment of the response of neutron matter with arbitrary spin polarization and we use it to estimate the mean free path of neutrinos as a function of the energy. The equation of state of spin-neutral and spin-polarized neutron matter has been computed employing an energy density functional starting from Quantum Monte Carlo results within two different neutron-neutron interaction schemes: one phenomenological (with the AV8'+UIX potential), and one based on chiral EFT potentials. We discuss the analogies and differences of the results, including the uncertainties due to the systematic error in the chiral expansion of the potential.