MICROSCOPIC DESCRIPTION OF NUCLEAR-REACTIONS - CLUSTER APPROXIMATION AND POTENTIAL HARMONICS

Series of potential harmonics are added to cluster channel functions t o go beyond the cluster approximation. An algorithm for an accurate nu merical calculation of the NN-interaction matrix in the potential-harm onic basis is developed. This algorithm is based on the method of rand om walks on a hypersphere and is applicable to the case of discrete sp ectra. The total cross sections for the fusion reaction d + t --> n alpha, for the elastic-scattering process n + alpha --> n' + alpha', a nd for the mirror reaction d + He-3 --> p + alpha are calculated and c ompared with experimental data.