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arXiv · 1602.05820

$\eta$ MAID-2015: update with new data and new resonances

V. L. Kashevarov·L. Tiator·M. Ostrick
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Abstract

Recent data for $\eta$ and $\eta\prime$ photoproduction on protons obtained by the A2 Collaboration at MAMI are presented. The total cross section for $\eta$ photoproduction demonstrates a cusp at the energy corresponding to the $\eta\prime$ threshold. The new data and existing data from GRAAL, CBELSA/TAPS, and CLAS collaborations have been analyzed by an expansion in terms of associated Legendre polynomials. %A Legendre decomposition shows the sensitivity to small partial-wave contributions. The isobar model $\eta$MAID updated with $\eta \prime$ channel and new resonances have been used to fit the new data. The new solution $\eta$MAID-2015 reasonably good describes the data in the photon beam energy region up to 3.7 GeV.

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V. L. Kashevarov, L. Tiator, M. Ostrick. 2016-02-18. $\eta$ MAID-2015: update with new data and new resonances. https://arxiv.org/abs/1602.05820

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