Effect of texture on the propagation of collective modes in superfluid 3He

A phenomenological theory of collective modes in sUperfluid 3He-B is developed Which is similar to the Leggett theory for spin dynamics. The theory can be applied to study the dynamics of collective modes in an inhomogeneous texture of the order parameter. In the teXture in the presence of a magnetic field the quantization axis of the momentum J, which characterizes the modes, varies in space. This results in a texture-dependent singularity of the Van Hove type in the absorption of ultrasound due to the excitation of collective modes. Thus in the texture produced by a magnetic field between parallel plates, the collective mode with J=2 observed by ultrasound should split into 10 lines instead of the 5 lines as in the case of an open geometry. Additional splitting of the mode spectrum dUe to the textures can be Used to investigate the vortex textures in a rotating superfluid liquid