Second order QCD corrections to qantiq-annihilation into a lepton pair at large transverse momentum

The theta(α/sub s//sup 2/) correction is presented to quark-antiquark-annihilation into a lepton pair at large transverse momentum. The corresponding hadron cross section difference dσ/d4q(pantip-pp) → e+e- + x (q is the momentum of the lepton pair system) has been calculated. The correction to this cross section difference is found to be large. This essentially agrees with recently published results by Ellis, Martinelli and Petronzio. Two important approximations are used: the invariant mass of the two-gluon-system is put to zero, and only valence-valence quark scattering is considered. (author)