Spin Echoes in LiquidHe3and Mixtures: A Predicted New Effect

We deduce that the "apparent" spin-diffusion coefficient $D_{\mathrm{eff}}$ measured by the spin-echo technique should show a maximum as a function of temperature. The effect is estimated to lie in the experimentally attainable range for both pure ${\mathrm{He}}^3$ and dilute mixtures, and should give a direct value of the Fermi-liquid parameter $Z_1$.