3pi photo-production with CLAS

Abstract

The $3\pi$ system produced in the reaction $\gamma p \to \pi^{+}\pi^{+}\pi^{-} n$ at $4.8-5.4$ GeV is investigated from the E01-017 (g6c) running of CLAS. This energy range allows for the study of excited mesons in the 1-2 GeV mass range, in their decay to $3\pi$, proceeding through $\rho \pi$ and $f_2 \pi$ emissions. At these energies, there is significant overlap in phase space for events with $\rho$ and $f_2$ production, recoiling off an excited baryon, such as the $\Delta(1232)$, $N^*(1520)$ and $N^*(1680)$. We show that after few kinematic selections, events of the latter type are suppressed in the final data set, allowing us to perform a PWA on the $3\pi$ system.