2025/05/30 by Benhar, Omar, Tonetto, Lucas
#FOS: Physical sciences #Nuclear Theory (nucl-th)
paper · doi:10.48550/arxiv.2505.24485
The temperature of a newly formed neutron star is believed to be as high as 1011~K, corresponding to a thermal energy of about 10 MeV. After a time t ∼ 50 \rm s, the neutrino mean free path in nuclear matter exceeds the typical star radius, R~∼~10 Km, and neutrino emission becomes the dominant mechanism of energy loss, eventually bringing the temperature down to ∼108~K. Neutrinos also play a critical role in determining the composition of matter in the star interior, consisting primarily of a charge-neutral mixture of neutrons, protons and leptons in β-equilibrium. This article provides an introduction to the weak interactions of nucleons in nuclear matter, as well as a concise review of the neutrino emission reactions taking place in the neutron star core. The approximations involved in the standard theoretical treatment of thermal and dynamical effects are analysed in the light of the recent progress of the field, and the prospects for future developments are outlined.