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Twist-3 contribution to the $γ^*γ\to ππ$ amplitude in the Wandzura-Wilczek approximation

N. Kivel·L. Mankiewicz
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Abstract

We have calculated the Wandzura-Wilczek contribution to the twist-3 part of $γ^*γ\to 2π$ amplitude. It describes interaction of the longitudinally polarized virtual photon with the real one, and it is suppressed by 1/Q, where $Q^2$ is the virtuality of the $γ^*$, as compared to the twist-2 contribution. We have found that, in the Wandzura-Wilczek approximation, factorization applies to the twist-3 amplitude.

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N. Kivel, L. Mankiewicz. 2000-10-16. Twist-3 contribution to the $γ^*γ\to ππ$ amplitude in the Wandzura-Wilczek approximation. https://doi.org/10.1103/physrevd.63.054017

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