Speaker
Description
The cooling effect of $^{63}$Fe$-$$^{63}$Mn Urca pair on the neutron star surface has been evaluated based on the state-of-the-art shell model calculations which reproduced the experimental spectroscopy results in the neutron-rich N $\sim$ 40 region. It is concluded that $^{63}$Fe$-$$^{63}$Mn could be among the strongest Urca pairs in the neutron star crust. This pair has been identified as the primary contributor to the cooling of neutron stars after type-I X-ray bursts, as demonstrated by crust cooling models. When considering this pair, carbon ignition is expected to occur at a deeper shell, potentially facilitating superburst ignition with X-ray burst residues. Consideration of $^{63}$Fe$-$$^{63}$Mn also improves the constraints that can be made on past surface nuclear burning on accreting neutron stars with observed quiescent cooling light curves.
