Spectroscopy with sound on superfluid 3He B

Collective modes of superfluid ³He B have been studied by means of sound attenuation and sound velocity studies. A new sound attenuation peak has been observed in superfluid ³He B at ?ω ≈ Δ(T). This peak has been identified with the real squashing mode. Pulse time of flight methods has been used in these studies. At high sound amplitudes, interesting transient effects have been observed which have been tentatively identified with solitonlike behavior.