Deep Inelastic Pion Electroproduction at Threshold
  We consider the cross section of the deep inelastic pion electroproduction on a proton target at threshold for Q^2 in the region 5-10 GeV^2. The corresponding amplitudes are described in terms of two form factors which we calculate using light cone sum rules (LCSR) to leading order in QCD and including higher twist corrections. Our results suggest a considerable change from a small Q^2 region that can be treated in the soft pion limit using current algebra. In particular, we obtain a \pi^0 to \pi^+ producton ratio of order 1/3 and significant nucleon helicity-flip contributions. 
V. M. Braun, D. Yu. Ivanov, A. Lenz and A. Peters