Magnetic collective excitations in the B phase of superfluid He-3

The dynamical susceptibility of the B phase of superfluid He-3 in the presence of dipolar coupling is calculated in the collisionless regime. Two poles of the susceptibility that correspond to the spin wave and the mode with energy gap (2/5 /sup 1/2/ 2Δ are found. The result agrees with that of Tewordt and Einzel qualitatively and contradicts the recent work by Maki. The residue of the high-frequency mode becomes remarkable near the transition temperature. The dispersion relations of these modes at T=O K and near the transition temperature are given in the most general form