Abstract
Applying arguments based on the operator product expansion for a three-point correlator and relying on quark-hadron duality, we derive an expression for the skewed (non-forward) parton distribution in the pion in the case of a zero-skewedness parameter We expect that our result is relevant for moderately large momentum transfers In addition, we construct a purely phenomenological factorized model for the same quantity in close analogy to Radyushkin’s model, originally proposed for skewed distributions of quarks in the nucleon. Though the quark-hadron duality approach supports theoretically the factorized model, the two models exhibit a different behavior in the parton momentum fraction X at any fixed t. The relevant process to distinguish between the two options seems to be the WACS off the pion that measures (to leading order) the inverse moment of the skewed distribution. Even after the inclusion of the first order kinematic corrections, the predictions for the cross section at c.m.s. scattering angles and 90° differ by factors of 3.5–3.9 and 2.9–7.5, respectively, so that a discrimination appears possible.
- Received 12 April 2000
DOI:https://doi.org/10.1103/PhysRevD.62.054018
©2000 American Physical Society