AZIMUTHAL ANGLES IN DIFFRACTIVE ep COLLISIONS
نویسنده
چکیده
We investigate azimuthal correlations in deep inelastic diffractive scattering, e+ p → e+ p̃+X. The dependence of the ep cross section on the angle between the lepton plane and some direction in the hadronic final state has a simple relation with cross sections and interference terms of the subreaction γ∗+p → X+ p̃. Its measurement can be used to constrain the cross section for longitudinally polarised photons. Using the model of nonperturbative two-gluon exchange of Landshoff and Nachtmann we calculate the distribution of the azimuthal jet angle in diffractive dijet production and find that useful bounds on the longitudinal cross section for such events might be obtained from its measurement. We then discuss the predictions of this model for the dependence of the ep cross section on the azimuthal angle of the proton remnant p̃, which contains information about the helicity content of the pomeron. The results for diffractive qq̄-production in the Landshoff-Nachtmann model are compared with those obtained in the phenomenological pomeron model of Donnachie and Landshoff. email: [email protected] Unité propre 14 du CNRS
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