Spin Down of Neutron Stars and Compositional Transitions in the Cold Crustal Matter

摘要

Transitions of nuclear compositions in the crust of a neutron star induced by stellar spin- down are evaluated at zero temperature. We construct a compressible liquid-drop model for the energy of nuclei immersed in a neutron gas, including pairing and shell correction terms, in reference to the known properties of the ground state of matter above neutron drip density, 4.3 * 10~11 g cm~-3. Recent experimental values and extrapolations of nuclear masses are used for a description of matter at densities below neutron drip. Changes in the pressure of matter in the crust due to the stellar spin- down are calculated by taking into account the structure of the crust of a slowly and uniformly rotating relativistic neutron star.