Reactionπ+d→π+π+π−dat 15 GeV/c

About 1800 events of the reaction ${\pi }^{+}d\to {\pi }^{+}{\pi }^{+}{\pi }^{-}d$ have been obtained from 387 000 photographs of the SLAC 82-in. bubble chamber corresponding to a 495 ± 25 μb cross section. The increasing cross section of this reaction with beam momentum is explained in terms of minimum momentum-transfer cutoff. The $D^{*}\mathrm{}\left(2200\right)\mathrm{}$ is observed as both $d{\pi }^{+}$ and $d{\pi }^{-}$ mass peaks. The $A_1\left({\rho }^0{\pi }^{+}\right)$ is consistent with a Deck-type mechanism. The $A_3\left(f^0{\pi }^{+}\right)$ is also observed, but the $A_4$ peak recently claimed is not seen in these data. There is no statistically significant $3\pi$ mass enhancement at the $A_2$ region, but indirect evidence indicates some $A_2$ production.