New method in Bardeen-Cooper-Schrieffer theory: Triplet pairing in superfluid dense neutron matter

On the basis of the method outlined in the first part of th is review, the properties of superfluid dense neutron matter are analyzed in the density r egion where the spin of a Cooper pair and its total angular momentum are S = 1 and J = 2, respectively. An analytic solution to the problem of P-3(2) pairing in neutron matter is presented. Basic features of the structure and of the energy spectrum of superfluid phases are discussed. Degeneracy that is absolutely dissimilar to that which is associated with the phase transf ormation of the order parameter in the S-pairing problem is a distinct feat ure of the structure of the aforementioned phases. It appears that one or e ven a few numbers characterizing the weight of components associated with d ifferent values of the projection M of the total angular momentum J = 2 of a Cooper pair can he chosen arbitrarily, while the others adjust to them in accordance with universal laws. As a result, the structure of any phase de pends neither on the density, nor on the temperature, nor on any other inpu t parameter. The phases found here form two groups degenerate in energy. On e of these groups comprises phases for which the sign of the order paramete r remains unchanged over the entire Fermi surface, while the other consists of phases whose order parameter has a zero. The energy splitting between t he phases from the different groups is calculated analytically as a functio n of temperature. The relative magnitude of this splitting changes from app roximately 3% at T = 0 to zero in the vicinity of the critical point T-c. T he role of tenser forces in dense neutron matter is analyzed. it is shown t hat the mixing of the orbital angular momenta L = I and L = 3 of Cooper pai rs that is induced hy tenser forces completely removes degeneracy peculiar to the P-3(2)-pairing problem-the number of phases and their structure at a given temperature are tightly fixed, while the energy spectrum of the phas es splits completely. (C) 2001 MAIK "Nauka/Interperiodica".