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An isobar model for eta photo- and electroproduction on the nucleon

Wen-Tai Chiang·Shin Nan Yang·L. Tiator·D. Drechsel
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Abstract

An isobar model containing Born terms, vector meson exchange and nucleon resonances is used to analyze recent eta photoproduction data for cross section and beam asymmetry, as well as JLab electroproduction data. Good overall description is achieved up to Q^2 = 4.0 (GeV/c)^2. Besides the dominant S11(1535) resonance, we show that the second S11 resonance, S11(1650), is also necessary to be included in order to extract S11(1535) resonance parameters properly. In addition, the beam asymmetry data allow us to extract very small (<0.1%) N* --> eta N decay branching ratios of D13(1520) and F15(1680) resonances because of the overwhelming s-wave dominance. The model is implemented as a part of the MAID program.

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Wen-Tai Chiang, Shin Nan Yang, L. Tiator, D. Drechsel. 2001-06-04. An isobar model for eta photo- and electroproduction on the nucleon. https://doi.org/10.1142/9789812810878_0022

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