Hard exclusive pion electroproduction at backward angles with CLAS

Abstract

We report on the first measurement of cross sections for exclusive deeply virtual pion electroproduction off the proton, $ep\to e^{\prime }n\ddot{I}{€}^{+}$, above the resonance region at backward pion center-of-mass angles. The $\ddot{I}{†}_{\ddot{I}}^{\ast }€$-dependent cross sections were measured, from which we extracted three combinations of structure functions of the proton. Our results are compatible with calculations based on nucleon-to-pion transition distribution amplitudes (TDAs) and shed new light on nucleon structure.

7 pages, 6figures