EXPERIMENTS TO SEARCH FOR A SUBSTRATE STATE FOR HE-3 ADJACENT TO SURFACES IN HE-3-HE-4 MIXTURES

We describe three experiments designed to search for the bound state f or He-3 adjacent to a substrate which has been predicted by Treiner an d co-workers. In each case a bulk He-3 - He-4 solution is in contact w ith the substrate of interest. For a Nuclepore substrate, NMR techniqu es are used to establish that there is no 2D behavior for the He-3 in the cell; thus, no substrate state is present. For a cesium of hydroge n substrate the technique involves the measurement of the velocity of ordinary sound in the bulk solution as function of temperature. The ce sium and hydrogen experiments are incomplete.