Photomeson production from neutrons bound in helium and deuterium

Photomeson production from neutrons bound in helium and deuterium was investigated by simultaneously measuring the angle and energy of the meson and the recoil proton. 270 Mev bremsstrahlung was used and Q in this experiment, only pions at 75° in the laboratory were measured. This corresponds roughly to 90° in the center of mass system of the photon and struck neutron. The angular distributions were interpreted to give the internal nuclear momentum distribution of the parent neutron by comparing the experimental data with a calculation based on the impulse approximation. The deuterium data agree both in shape and in absolute magnitude with predictions based on the Hulthen wave function. The helium data indicate that the neutrons involved in photomeson production have fewer high momentum components in their wavefunctions than those found from other types of experiments. This result is interpreted as evidence for the reabsorption of mesons by the parent nucleon and another nucleon interacting strongly with it, to produce pseudodeuteron photodisintegrations. These strong two body interactions are believed responsible for the high momentum components of the internal nuclear momentum distribution.published or submitted for publicationU of I Onlythesi