Measurements along the Melting Curve ofHe3at Millikelvin Temperatures

Abstract

The melting curve of pure ${\mathrm{He}}^3$ has been measured in the region of the "$A$" and "$B$" phenomena discovered by Osheroff, Richardson, and Lee. Within a 2% precision there is no effect of the "$A$" phenomenon on the slope of the equilibrium melting curve. This indicates that "$A$" is not related to the properties of solid ${\mathrm{He}}^3$. Also, we describe a new effect on thermal relaxation of a powdered-cerium-magnesium-nitrate thermometer immersed in ${\mathrm{He}}^3$.