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arXiv · 1312.6133

The photon-pion transition form factor: incompatible data or incompatible models?

J. P. B. C. de Melo·B. El-Bennich·T. Frederico
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Abstract

The elastic and $γ\to π$ transition form factors of the pion along with its usual static observables are calculated within a light-front field approach to the constituent quark model. The focus of this exercise in a simple model is on a unified description of all observables with one singly parametrized light-front wave function to detect possible discrepancies in experimental data, in particular the contentious large momentum-squared data on the transition factor as reported by BaBar and Belle. We also discuss the relation of a small to vanishing pion charge radius with an almost constant pion distribution amplitude and compare our results with those obtained in a holographic light-front model.

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J. P. B. C. de Melo, B. El-Bennich, T. Frederico. 2013-12-20. The photon-pion transition form factor: incompatible data or incompatible models?. https://doi.org/10.1007/s00601-014-0853-z

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