Search

The cross section for the reaction ep → e'pπ+π- was measured in the resonance region for 1.4 < W < 2.1 GeV and 0.5 < Q² <1.5 GeV²/c² using the CIJAS detector at Jefferson Laboratory. The data show resonant. structures not. visible in previous experiments. The comparison of our data to a phenomenological prediction using available information on N* and Δ states shows an evident discrepancy. A better description of the data is obtained either by a sizeable change of the properties of the P13(1720) resonance or by introducing a new baryon state, not reported in published analyses. [ABSTRACT FROM AUTHOR]