Hard exclusive electroproduction of two pions

We have calculated the leading order amplitude of hard exclusive production of two pions in lepton nucleon scattering. At leading twist a pion pair can be produced only in an isospin one or zero state. We have shown that isoscalar states are produced predominantly for xBj>0.3 and with an invariant mass of the two pions close to the threshold (S-wave) and in the f2 resonance region (D-wave). These isoscalar pion pairs are mostly produced by two collinear gluons. Hence, comparing the production of charged and neutral pion pairs as a function of xBj and mππ, one can get information about the gluonic component of two-pion distribution amplitudes.