EXCLUSIVE PRODUCTION OF SOFT PIONS IN DIS

We consider pion electroproduction close to threshold for Q2 in the region 1–10 GeV2 on a nucleon target. The momentum transfer dependence of the S-wave multipoles at threshold, E0+ and L0+, is calculated in the chiral limit using light-cone sum rules. Predictions for the cross sections in the threshold region, both for π0p and π+n channels, are given that include P-wave contributions that, as we argue, are model independent to a large extent. The results are compared with the SLAC E136 data on the structure function F2(W,Q2) in the threshold region.

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