Interactions Between ${\mathrm{He}}^3$ Atoms in Dilute Solutions of ${\mathrm{He}}^3$ in Superfluid ${\mathrm{He}}^4$

The magnitude, sign, and momentum dependence of the effective interaction between ${\mathrm{He}}^3$ atoms in superfluid ${\mathrm{He}}^4$ are derived from the experimental data. Calculations of the Fermi-liquid parameters for the normal state of ${\mathrm{He}}^3$ in solution yield results in agreement with experiment; the temperature for a superfluid transition associated with the ${\mathrm{He}}^3$ is estimated to be ∼2×${10}^{-6\mathrm{}}$ °K.