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Evidence for the flavor singlet axial anomaly related effects in $ϕ$ meson electromagnetic production at large momentum transfers

N. I. Kochelev·V. Vento
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Abstract

The gluonic contributions to the conventional PCAC formulas due to flavor singlet axial anomaly have been instrumental in explaining the mass of the $η^{\prime}$ and providing a plausible explanation for solving the spin crisis. We show that they also play an important role in the description of photo- and electroproduction of vector mesons at low energy and high momentum transfers. We calculate the contributions of this type to $ϕ$ meson electromagnetic production in a model, which contains also a soft pomeron, and find agreement with recent CLAS data.

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N. I. Kochelev, V. Vento. 2001-07-14. Evidence for the flavor singlet axial anomaly related effects in $ϕ$ meson electromagnetic production at large momentum transfers. https://doi.org/10.1016/s0370-2693(01)00894-2

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