MICROSCOPIC CALCULATION OF THE HE-4 SYSTEM

We report on a consistent, microscopic calculation of the bound and sc attering states in the He-4 system employing a realistic nucleon-nucle on potential in the framework of the resonating group model (RGM). We present for comparison with these microscopic RGM calculations the res ults from a charge-independent, Coulomb-corrected R-matrix analysis of all types of data for reactions in the A = 4 system, Comparisons are made between the phase shifts, and with a selection of measurements fr om each reaction, as well as between the resonance spectra obtained fr om both calculations. In general, the comparisons are favorable, but d istinct differences are observed between the RGM calculations and some of the polarisation data. The partial-wave decomposition of the exper imental data produced by the R-matrix analysis shows that these differ ences can be attributed to just a few S-matrix elements, for which ina dequate tenser-force strength in the N-N interaction used appears to b e responsible.