Exclusive pion cross section and asymmetry at HERMES
نویسنده
چکیده
Exclusive electroproduction of π + mesons was studied by scattering 27.6 GeV positrons or electrons off a gaseous hydrogen target. The spin-averaged cross section and the single-spin azimuthal asymmetry with respect to transverse target polarisation were measured as a function of the Man-delstam variable t, the Bjorken scaling variable x B , and the virtuality Q 2 of the exchanged photon. The results are compared to recent theoretical models. Exclusive pion cross section and asymmetry at HERMES Ivana HRISTOVA
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