Azimuthal asymmetries at CLAS: Extraction ofea(x)and prediction ofAUL

The first information on the chirally odd twist-3 proton distribution function ${e}^{a}(x)$ is extracted from the azimuthal asymmetry ${A}_{\mathrm{LU}}$ in the electroproduction of pions from deeply inelastic scattering of longitudinally polarized electrons off unpolarized protons, which has been recently measured by the CLAS Collaboration. Furthermore parameter-free predictions are made for the azimuthal asymmetries ${A}_{\mathrm{UL}}$ from scattering of an unpolarized beam on a polarized proton target for CLAS kinematics.