EFFECTIVE-MASS OF ONE HE-4 ATOM IN LIQUID-HE-3

A microscopic calculation of the effective mass of one He-4 impurity i n homogeneous liquid He-3 at zero temperature is performed for an exte nded Jastrow-Slater wave function, including two- and three-body dynam ical correlations and also backflow correlations between the He-4 atom and the particles in the medium. The effective mass at equilibrium de nsity, m4/m4 = 1.21, is in very good agreement with the recent experi mental determination by Edwards et al. The three-particle correlations appear to give a small contribution to the effective mass and differe nt approximations for the three-particle distribution function give al most identical results for m4/m4.