PHONON PHYSICS AND THE DETECTION OF SOLAR NEUTRINOS

We present a summary of recent progress towards the development of a s olar neutrino detector in which superfluid helium is used as a target material. In this detector phonons and rotons generated in the liquid by a recoiling particle propagate through the liquid and then cause a shower of atoms to be quantum evaporated from the liquid surface. We d escribe recent results which indicate that roton-roton interactions cl ose to the track of the recoiling particle may make it possible to obt ain information about the track direction.