Probing the DeltaNN component of 3He
/ Authors
G. Huber, G. Lolos, E. Brash, S. Dumalski, F. Farzanpay, M. Iurescu, Z. Papandreou, A. Shinozaki, A. Weinerman, T. Emura
and 16 more authors
H. Hirosawa, K. Niwa, H. Yamashita, K. Maeda, T. Terasawa, H. Yamazaki, S. Endo, K. Miyamoto, Y. Sumi, G. Garino, K. Maruyama, A. Leone, R. Perrino, T. Maki, A. Sasaki, Y. Wada
/ Abstract
The 3He(gamma,pi^+/- p) reactions were measured simultaneously over a tagged photon energy range of 800<E_gamma<1120 MeV, well above the Delta resonance region. An analysis was performed to kinematically isolate Delta knockout events from conventional Delta photoproduction events, and a statistically significant excess of pi+p events was identified, consistent with Delta++ knockout. Two methods were used to estimate the DeltaNN probability in the 3He ground state, corresponding to the observed knockout cross section. The first gave a lower probability limit of 1.5+/-0.6+/-0.5%; the second yielded an upper limit of about 2.6%.
Journal: Physical Review C