Even at moderate energy machines, there is a regime where hard pion electroproduction proceeds by a perturbatively calculable process. The process, we claim, is not the leading twist fragmentation one but a rather higher twist process that produces kinematically isolated pions. Semiexclusive data may teach us more about parton distribution functions of the target and the pion distribution amplitude. In addition, there is a connection to generalized parton distribution calculations of exclusive processes in that the perturbative kernel is the same.

Authors: Andrei Afanasev, Carl E. Carlson

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