DISSIPATION IN DIAPHRAGM DRIVEN FLOW OF SUPERFLUID HE-3-B

We have measured the resonant frequencies and bandwidths of two of the modes of transverse vibration of a kapton diaphragm separating two disk shaped regions of superfluid He-3-B of radius 2 can and nominal height 100 mum The measurements agree well with theoretical calculations. In the temperature range investigated the dissipation is dominated by incomplete clamping of normal fluid flow in the plane of the disk. The cell is mounted on the Manchester rotating millidegree cryostat and will be used to investigate the mutual friction force on the superflow due to the presence of an array of quantized vortices.