The phase transitions in a realistic system with triplet pairing, dense neutron matter, have been investigated. The spectrum of phases of the ${}_{}{}^3{}_{}{}^{}P_2^{}{}_{}{}^{}-{}_{}{}^3{}_{}{}^{}F_2^{}{}_{}{}^{}$ model, which adequately describes pairing in this system, is analytically constructed with the aid of a separation method for solving BCS gap equations in states of arbitrary angular momentum. In addition to solutions involving a single value of the magnetic quantum number (and its negative), there exist ten real multicomponent solutions. Five of the corresponding angle-dependent order parameters have nodes, and five do not. In contrast to the case of superfluid ${}^3\mathrm{He}$, transitions occur between phases with nodeless order parameters.

• Received 10 January 2001

DOI:https://doi.org/10.1103/PhysRevLett.87.031103