Photoproduction of theA2Meson in the Reactionγp→nπ+π+π−and an Estimate of theA2γπWidth

Abstract

We observe production of the $A_2$ meson in the reaction $\gamma p\to n{\pi }^{+}{\pi }^{+}{\pi }^{-}$ at 4.3 and 5.25 GeV. The data are consistent with a one-pion-exchange production mechanism and we give an estimate of $\Gamma (A_2\to \gamma \pi )\approx 0.5$ MeV. A similar value for $\Gamma (A_2\to \gamma \pi )$ is also obtained using a vector dominance model.