The Solubility ofHe3in LiquidHe4

Measurements are reported of the distribution coefficient for ${\mathrm{He}}^3$ between solutions of ${\mathrm{He}}^3$ in liquid ${\mathrm{He}}^4$ and their saturated vapors in the temperature range 1.4°K to 2.6°K. The results obtained below the $\lambda$-temperature give values for $\frac{C_V}{C_L}$ higher than those calculable for perfect classical solutions, but in good agreement with the theory previously proposed by Heer and Daunt. Above 2.18°K, the $\lambda$-temperature for pure liquid ${\mathrm{He}}^4$, the measured $\frac{C_V}{C_L}$ also appears greater than that for perfect calssical solutions, as was predicted by Heer and Daunt. A comparison with the theory of de Boer and Gorter is also given.