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arXiv · 0706.0616

Eta Photoproduction as a Test of the Extended Chiral Symmetry

C. Fernandez-Ramirez·E. Moya de Guerra·J. M. Udias
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Abstract

We analyze the $γp \to ηp$ process from threshold up to 1.2 GeV, employing an effective Lagrangian approach that allows for a mixing of eta couplings of pseudoscalar and pseudovector nature. The mixing ratio of the couplings may serve as a quantitative estimation of the $SU_L(3)\times SU_R(3)$ extended chiral symmetry violation in this energy regime. The data analyzed (differential cross sections and asymmetries) show a preference for the pseudoscalar coupling -- 91% of pseudoscalar coupling component for the best fit. We stress that a more conclusive answer to this question requires a more complete electromagnetic multipole database than the presently available one.

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C. Fernandez-Ramirez, E. Moya de Guerra, J. M. Udias. 2007-06-05. Eta Photoproduction as a Test of the Extended Chiral Symmetry. https://doi.org/10.1016/j.physletb.2007.06.049

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