On wide-angle photo- and electroproduction of pions to twist-3 accuracy
DOI:
https://doi.org/10.31349/SuplRevMexFis.3.0308113Keywords:
exclusive processes, meson production, generalized parton distributions, distribution amplitudes, higher twistAbstract
The wide-angle photo- and electroproduction of pions is investigated within the handbag mechanism in which the γ (∗)N → πN0 amplitudes factorize into subprocess amplitudes,γ (∗) q → πq0 , and form factors representing 1/x-moments of generalized parton distributions (GPDs). The subprocess is calculated to twist-3 accuracy taking into account both the 2- and 3-body Fock components of the pion. The cross-sections are compared to experiment and spin-effects are discussed.
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