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Diffractive vector mesons beyond the s-channel helicity conservation

E. V. Kuraev·N. N. Nikolaev·B. G. Zakharov
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Abstract

We derive a full set, and determine the twist, of helicity amplitudes for diffractive production of light to heavy vector mesons in deep inelastic scattering. For large $Q^{2}$ all helicity amplitudes but the double-flip are calculable in perturbative QCD and are proportional to the gluon structure function of the proton at a similar hard scale. We find a substantial breaking of the $s$-channel helicity conservation which must persist also in real photoproduction.

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E. V. Kuraev, N. N. Nikolaev, B. G. Zakharov. 1998-10-07. Diffractive vector mesons beyond the s-channel helicity conservation. https://doi.org/10.1134/1.567931

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