Measurement of fountain pressure and other thermal properties in superfluid3He

Abstract

The fountain pressure, heat capacity, and thermal conductivity of superfluid 3 He have been measured simultaneously at pressures of 29, 23.2, 10, and 2.5 atm and at the saturated vapor pressure. If the fountain equation, based on the two-fluid model, is used to compute the entropy from the observed fountain pressure, it is consistent with the entropy obtained by integrating the specific heat. The measured thermal conductivities are dominated by a diffusive conductivity which is inversely proportional to the temperatureT c .