Speaker
Description
Results of the phenomenological analysis of $\eta$ and $\eta'$
photoproduction on the protons and the neutrons with updated version of
EtaMAID model are presented.The model includes 23 nucleon resonances parameterized with Breit-Wigner shapes, $t$-channel exchange of vector and axial-vector mesons with Regge cuts,and Born terms in $s$ and $u$ channels.
A new approach is discussed to avoid double counting in the overlap region of Regge and resonances. Parameters of the resonances were obtained from a fit to available experimental data. The model well describes both differential cross sections and polarization observables for photoproduction of $\eta$ and $\eta'$ on the nucleons at photon beam energies from the threshold up to 9 GeV.
A comparison is done among four newly updated partial waves analyses for
observables and partial waves. The nature of the most interesting specifics in the data is discussed.