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arXiv · hep-ph/0007293

Axial U(1) dynamics in eta and eta' photoproduction

Steven D. Bass·Stefan Wetzel·Wolfram Weise
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Abstract

We discuss the sensitivity of eta and eta' photoproduction near threshold to the gluonic OZI breaking parameters in the U_A(1)-extended effective chiral Lagrangian for low-energy QCD. Our coupled-channels analysis hints at a strong correlation between the gluon-induced contributions to the eta' mass and the low-energy pp -> pp eta' reaction and the near-threshold behaviour of the gamma p -> eta p cross-section.

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Steven D. Bass, Stefan Wetzel, Wolfram Weise. 2000-07-26. Axial U(1) dynamics in eta and eta' photoproduction. https://doi.org/10.1016/s0375-9474(00)00574-1

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