Contribution Leading parallel
New Baryon States in Exclusive Meson Photo-/Electroproduction with CLAS
Studies of the spectrum of the excited states of the nucleon (N) with a focus on the search for states predicted in quark models but still not observed, known as the "missing" resonances", has represented a hot topic in hadron physics for several decades. Recently, several new (previously "missing") N states have been discovered from a global multichannel analysis of exclusive photoproduction with a decisive impact from the CLAS KY data. Further extension of these efforts towards combined studies of exclusive photo- and electroproduction will be presented in this talk. The combined studies of p+pp photo- and electroproduction data from CLAS has revealed the presence of the new N'(1720)3/2+ baryon state in addition to the new baryon states discovered in photoproduction. Implementation of the new N'(1720)3/2+ resonance is needed in order to describe the p+pp photo- and electroproduction cross sections with photon virtuality Q2 independent masses and hadronic decay widths of all resonances relevant in the third resonance region. So far, the N'(1720)3/2+ is the only new baryon state for which the information on the Q2 -evolution of the electroexcitation amplitudes has become available, offering insight into the particular structural features of "missing" resonances that have made them so elusive from detection.