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arXiv · 1207.2503

Theory and phenomenology of helicity amplitudes for high energy exclusive leptoproduction of the rho-meson

I. V. Anikin·A. Besse·D. Yu. Ivanov·B. Pire·L. Szymanowski·S. Wallon
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Abstract

We review here two approaches to describe hard leptoproduction of transversally polarized rho-meson, based on recent calculation of the gamma*T -> rhoT impact factor up to twist 3 accuracy in the collinear factorization frame, including 2- and 3- particles Fock-states. The first approach uses a model of the unintegrated gluon density (the proton impact factor) which allows a comparison of our predictions with H1 and ZEUS data for the ratios of helicity amplitudes T(gamma*T -> rhoT)/T(gamma*L -> rhoL) and T(gamma*T -> rhoL)/T(gamma*L -> rhoL). In the second approach, we transform the gamma*T -> rhoT impact factor into the impact parameter space. We show that the transformed amplitude factorizes according to conventional dipole picture. We shortly discuss a way to implement the nucleon saturation effects in our approach.

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I. V. Anikin, A. Besse, D. Yu. Ivanov, B. Pire, L. Szymanowski, S. Wallon. 2012-07-10. Theory and phenomenology of helicity amplitudes for high energy exclusive leptoproduction of the rho-meson. https://arxiv.org/abs/1207.2503

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