A $p-\gamma$ coincidence experiment has been performed with 400-MeV protons. The angular and momentum analysis of the scattered proton demonstrates a primary quasifree process. The residual nuclei which have been identified from the $\gamma$-ray spectra characterize the final states and indicate an evaporation process or a sequential ejection at low energy of some correlated nucleons. In addition, preliminary results with triple coincidences ($2p-\gamma$) indicate a promising way to clarify the mechanism of quasifree reactions.

• Received 13 July 1977

DOI:https://doi.org/10.1103/PhysRevLett.40.164