The e p -> e' p eta reaction at and above the S11(1535) baryon resonance
arXiv:hep-ex/0011029 · doi:10.1103/PhysRevLett.86.1702
Abstract
New cross sections for the reaction e p -> ep eta are reported for total center of mass energy W = 1.5--1.86 GeV and invariant momentum transfer Q^2 = 0.25--1.5 GeV^2. This large kinematic range allows extraction of important new information about response functions, photocouplings, and eta N coupling strengths of baryon resonances. Expanded W coverage shows sharp structure at W \~ 1.7 GeV; this is shown to come from interference between S and P waves and can be interpreted in terms of known resonances. Improved values are derived for the photon coupling amplitude for the S11(1535) resonance.
11 pages, RevTeX, 5 figures, submitted to Phys. Rev. Lett