Deuteron break-up reaction on 4He

The continuous proton spectra from the deuteron break-up reaction on 4he have been studied at deuteron incident energies of 6.8 and 7.8 MeV with a magnetic spectrograph. The total reaction cross section was derived from the data at 7.8 MeV and compared with that calculated from the phase shift set obtained by the ETH group using the data from the elastic channel. Each spectrum has a peak corresponding to the formation of 5He ground state. The DWBA calculation carried out on the assumption that the ground state of 5He is described by a potential resonance, provides a good description of the angular distribution in the forward angles. In particular, the calculation using the Johnson approximation reproduces even the absolute magnitude of the cross section. (auth.)