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arXiv · 0803.2847

Pion-to-photon transition distribution amplitudes in the non-local chiral quark model

Piotr Kotko·Michal Praszalowicz
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Abstract

We apply the non-local chiral quark model to study vector and axial pion-to-photon transition amplitudes that are needed as a nonperturbative input to estimate the cross section of pion annihilation into the real and virtual photon. We use a simple form of the non-locality that allows to perform all calculations in the Minkowski space and guaranties polynomiality of the TDA's. We note only residual dependence on the precise form of the cut-off function, however vector TDA that is symmetric in skewedness parameter in the local quark model is no longer symmetric in the non-local case. We calculate also the transition form-factors and compare them with existing experimental parametrizations.

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Piotr Kotko, Michal Praszalowicz. 2009-01-30. Pion-to-photon transition distribution amplitudes in the non-local chiral quark model. https://arxiv.org/abs/0803.2847

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