Collective excitations of a quantized vortex in P32 superfluids in neutron stars

We discuss collective excitations (both fundamental and solitonic excitations) of quantized superfluid vortices in neutron ^P3₂ superfluids, which likely exist in high density neutron matter such as neutron stars. Besides the well-known Kelvin modes (translational zero modes), we find a gapful mode whose low-energy description takes the simple form of a double sine-Gordon model. The associated kink solution and its effects on spontaneous magnetization inside the vortex core are analyzed in detail.