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The e p -> e' p eta reaction at and above the S11(1535) baryon resonance

The CLAS Collaboration·R. Thompson
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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.

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The CLAS Collaboration, R. Thompson. 2000-11-09. The e p -> e' p eta reaction at and above the S11(1535) baryon resonance. https://doi.org/10.1103/physrevlett.86.1702

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