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 CLAS 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 sizable change of the properties of the P13(1720) resonance or by introducing a new baryon state, not reported in published analyses.
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