New cross sections for the reaction ep→e′ηp are reported for total center-of-mass energy W=1.5-2.3 GeV and invariant squared momentum transfer Q2=0.13-3.3 GeV2. This large kinematic range allows the extraction of new information about response functions, photocouplings, and ηN coupling strengths of baryon resonances. A sharp structure is seen at W~1.7 GeV. The shape of the differential cross section is indicative of the presence of a P-wave resonance that persists to high Q2. Improved values are derived for the photocoupling amplitude for the S11(1535) resonance. The new data greatly expand the Q2 range covered, and an interpretation of all data with a consistent parametrization is provided.
Physical Review C
Denizli, H.; Biselli, Angela; and CLAS Collaboration, "Q2 dependence of the S11(1535) photocoupling and evidence for a P-wave resonance in η electroproduction" (2007). Physics Faculty Publications. 67.
H. Denizli et al. [CLAS Collaboration], "Q2 dependence of the S11(1535) photocoupling and evidence for a P-wave resonance in η electroproduction", Physical Review C 76.1 (2007) DOI: 10.1103/PhysRevC.76.015204