Helium film flow below 1°K

The critical transfer rate of the helium II film was measured at temperatures between 0.3°K and the lambda point. Filling rates of a small beaker enclosed in a sealed glass capsule which could be tipped as a whole were studied. A technique was developed whereby the glass capsule could be sealed off at room temperature with 750 psig of helium gas, sufficient to provide enough liquid within the capsule at the low temperatures. It was found that the rate of flow at 0.3°K rises 25% above the value at the flat minimum near 1°K, in approximate agreement with the results of Ambler and Kurti