The inclusive proton spectrum for $$\bar pd \to 3\pi p$$ at rest re-examined

Abstract

We re-analyze the spectator proton distribution for ¯pd→π+ π− π−p. For this channel previous calculations underestimated the cross section for proton momenta of 300 to 600 MeV/c by about a factor 7 while the channels with higher pion multiplicities and the ¯pd→K¯ Kmπp reactions were well explained. By using detailed experimental information on ¯pn and ¯pp annihilation, meson rescattering can in fact explain the cross section also for the 3π case. The¯ pp annihilation followed by charge exchange pion rescattering is much larger than in the 5π case. Vector meson exchange is small but not negligible at high spectator momenta.