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THE LARGE MOMENTUM TRANSFER BEHAVIOUR OF MESON-PHOTON TRANSITION FORM FACTORS

P. Kroll
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Abstract

It is reported on predictions for the $π$-$γ$ transition form factor obtained within a perturbative approach which includes transverse momentum effects and Sudakov corrections. The results clearly favor distribution amplitudes close to the asymptotic form, $\sim x_1x_2$, and disfavor distribution amplitudes which are strongly concentrated in the end-point regions. Applications of that approach to the $η$-$γ$ and $η^\prime$-$γ$ transition form factors are discussed as well.

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P. Kroll. 1995-04-26. THE LARGE MOMENTUM TRANSFER BEHAVIOUR OF MESON-PHOTON TRANSITION FORM FACTORS. https://arxiv.org/abs/hep-ph/9504394

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