Features of theπ+d→π+π+π−dreaction at 6 GeV/c

We have studied the coherent ${\pi }^{+}d\to {\pi }^{+}{\pi }^{+}{\pi }^{-}d$ reaction using a sample of 4019 events having a visible final-state deuteron. The total cross section, corrected for invisible deuteron events, was found to be 380±50 μb. The main features of the data are the large production of ${\rho }^0$ (90%), with a corresponding ${\rho }^0{\pi }^{+}$ enhancement in the $A_1$ region, and the observation of the $d\pi$ enhancement at ∼2.2 GeV.