THE VACANCY DIFFUSION IN BCC 3HE. V.V. Boiko, N V. Zuev, N.E. Dyumin, V.N. Grigor'ev, SNG, Ukraine 310164, Kharkov Lenin Avenue, 47, Ukraine.

It is study a diffusion in solid 3He using the diffusion flow through a porous membrane new method, which was elaborated and successfully employed in investigation by the authors earlier. The diffusion flow in BCC crystals of 3He is measured at the three values of molar volume. The self diffusion coefficient of 3He is determined in the temperature range 0,45 - 0,7 K, as well as vacancy diffusion coefficient which are found to be temperature independent. In the frames of the model of wide-zone quasiparticles the method is proposed for direct determination of the vacancion zone width ([[Delta]]), with using the comparison of experimental date for self - diffusion and heat capacity. The values of [[Delta]] obtained are sufficiently large than temperature giving the evidence for the legitimity of using the model of wide-zone quasiparticls.