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arXiv · 0801.0778

Photoproduction off the nucleon revisited: Evidence for a narrow N(1688) resonance?

V. Kuznetsov·M. V. Polyakov·T. Boiko·J. Jang·A. Kim·W. Kim·A. Ni·G. Yang
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Abstract

Revised analysis of $Σ$ beam asymmetry for the $η$ photoproduction on the free proton reveals a structure at $W\sim 1.69$ GeV. Fit of the experimental data based on the E429 solution of the SAID partial wave analysis suggests a narrow ($Γ\leq 25$ MeV) resonance. Possible candidates are $P_{11}, P_{13}$, or $D_{13}$ resonances. The result is considered in conjunction with the recent evidence for a bump-like structure at $W\sim 1.67 - 1.68$ GeV in the quasi-free $η$ photoproduction on the neutron.

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V. Kuznetsov, M. V. Polyakov, T. Boiko, J. Jang, A. Kim, W. Kim, A. Ni, G. Yang. 2008-01-05. Photoproduction off the nucleon revisited: Evidence for a narrow N(1688) resonance?. https://doi.org/10.1007/978-3-540-85144-8_33

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