MEAN-FIELD CALCULATIONS OF QUASI-ELASTIC RESPONSES IN HE-4

We present calculations of the quasielastic responses functions in He- 4 based upon a mean-field model used to perform analogous calculations in heavier nuclei. The meson exchange current contribution is small i f compared with the results of calculations where short-range correlat ions are explicitly considered. It is argued that the presence of thes e correlations in the description of the nuclear wave functions is cru cial to make meson exchange current effects appreciable.