Table of contents

Presentation

I Introductie

II Overdamped phonens in Fluid Helium at 4 K

III Comment and Reply on "Overdamped Phonons in Fluid Helium at 4 K"

IV Dynamics in He at 4 and 8K from inelastic Neutron scattering

V Structure of Helium at 4 and 8 K from Neutron Diffraction

VI To be supplied....