4-CHARGED-PARTICLE FINAL STATES FROM INTERACTION OF 2.7-GEV/C PI+ ON DEUTERIUM

Reactions leading to four nonstrange, charged particles from the interaction of 2.7-GeV/c + on deuterium have been studied. Only events containing at least one visible stopping proton track were included. The spectator model of the +d interaction has been examined and found to be a good approximation. This model not only gives a good description of the final state of the spectator nucleon, but is also supported by the similarity of such reacitons as +dpp0 and -pn0. Meson (M) resonance production in the reaction +dppM is prominent, including (0.210.04 mb),(0.800.08 mb), (2.200.25 mb), f(0.510.20 mb), A1(0.170.10 mb), A2(0.140.08 mb), and (0.050.02 mb) (errors are statistical). The baryon resonance (1238) is also observed to be produced in a variety of reactions. The and production processes have been examined in some detail, including a determination of the spin density matrix elements. Also, the 3 system in the pp+-0 final state has been studied at energies near the A1 and A2 masses in an attempt to separate these particles from the several other processes contributing to this final state. The results of a spin-parity analysis of the A mesons are presented. © 1969 The American Physical Society.