Twist-3 contributions to wide-angle photoproduction of pions

Understand

We investigate wide-angle pi^0 photoproduction within the handbag approach to twist-3 accuracy.

• In contrast to earlier work both the 2-particle as well as the 3-particle twist-3 contributions are taken into account.
• It is shown that both are needed for consistent results that respect gauge invariance and crossing properties.
• The numerical studies reveal the dominance of the twist-3 contribution.