On the theory of superfluidity of dense neutron matter with anisotropic spin-triplet p-wave pairing in strong magnetic fields

Abstract

The previously derived nonlinear integral equations for the components of the order parameter (OP) of dense superfluid neutron matter (SNM) with anisotropic spin-triplet p-wave pairing (similar to 3He-A), taking into account the effects of magnetic field and finite temperatures, are reduced here to the equations for the two components of OP at the limit of zero temperature. In this article, these equations (which are valid for arbitrary parametrization of the effective Skyrme interaction in neutron matter) are specified and solved numerically for the generalized BSk21 parametrization of the effective Skyrme forces (with additional terms dependent on density n) in neutron matter. The primary result is the splitting of the energy gap, calculated in the energy spectrum of neutrons in SNM (nonlinearly increasing under a moderately strong magnetic field H), which has a nonlinear dependency on density n in the limiting case of zero temperature. A small asymmetry (nonlinearly increasing with magnetic field) of the energy gap splitting has also been obtained in the range of moderately strong magnetic fields 1016 G ≤ H ≤ 1017 G. Neutron matter phase transitions to superfluid states of such a type and magnetic field strength might occur (and exist) at subnuclear and supranuclear densities, as in the liquid outer core of magnetars (strongly magnetized neutron stars).