A theoretical study of the $\overline{p}p\to \overline{p}n{\pi }^{+}$ reaction for antiproton beam energy from $1$ to $4$ GeV is made by including contributions from various known $N^{*}$  and ${\Delta }^{*}$ resonances. It is found that for the beam energy around $1.5$ GeV, the contribution of the Roper resonance $N_{(1440)}^{*}$ produced by the $t$-channel $\sigma$ exchange dominates over all other contributions. Since such a reaction can be studied in the forthcoming PANDA experiment at the GSI Facility of Antiproton and Ion Research (FAIR), the reaction will be realistically the cleanest place for studying the properties of the Roper resonance and the best place for looking for other “missing” $N^{*}$ resonances with large coupling to $N\sigma$.

• Received 23 May 2009

DOI:https://doi.org/10.1103/PhysRevC.80.045211