Resonance Production of Two Pions in the Reaction $pd\rightarrow pd\pi \pi$ at 1–2 GeV

Abstract

The recent ANKE@COSY data on the reaction $pd\rightarrow pd\pi \pi$ demonstrate a peak at invariant mass of the final $d\pi \pi$ system $M_{d\pi \pi }=2.38$ GeV that corresponds to the isocalar $J^P=3^+$ dibaryon $D_{03}$. The data are analyzed within a theoretical model assuming excitation of the $D_{03}$ dibaryon via the $\sigma$-meson exchange. An upper limit on the partial width $D_{03}\rightarrow d\sigma$ is estimated from comparison to the data.