Baryon resonance analysis from two pion electroproduction at Jefferson Laboratory
INFN, Sezione di Genova, Via Dodecaneso 33, I-16146, Genova, Italy
Published online: 12 February 2004
The cross section for the reaction e p → e ′ p π + π - was measured in the resonance region for 1.4<W<2.1 GeV and 0.5<Q 2<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 sizeable change of the properties of the P 13(1720) resonance or by introducing a new baryon state, not reported in published analyses.
PACS: codes. – 13.60.Le - Meson production / codes. – 13.40.Gp - Electromagnetic form factors / codes. – 14.20.Gk - Baryon resonances with S=0
© Società Italiana di Fisica, Springer-Verlag, 2004