New Results from the Studies of the $N(1440)1/2^+$, $N(1520)3/2^-$, and $\Delta(1620)1/2^-$ Resonances in Exclusive $ep \to e'p' \pi^+ \pi^-$ Electroproduction with the CLAS Detector

In this study, the transition helicity amplitudes from the proton ground state to the N(1440)1/2+, N(1520)3/2–, and Δ(1620)1/2– resonances (γvpN* electrocouplings) were determined from the analysis of nine independent onefold differential π+π–p electroproduction cross sections off a proton target, taken with CLAS at photon virtualities 0.5GeV2 < Q2 < 1.5 GeV2. The phenomenological reaction model employed for separation of the resonant and nonresonant contributions to this exclusive channel was further developed.