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arXiv · hep-ph/9905378

Conformal couplings and ``azimuthal matching'' of QCD Pomerons

N. Marchal·R. Peschanski
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Abstract

Using the asymptotic conformal invariance of perturbative QCD we derive the expression of the coupling of external states to all conformal spin-p components of the forward elastic amplitude. Using the wave-function formalism for structure functions at small x, we derive the perturbative coupling of the virtual photon for p= 1, which is maximal for linear transverse polarization. The non-perturbative coupling to the proton is discussed in terms of ``azimuthal matching'' between the proton color dipoles and the quark- antiquark configurations of the photon. As an application, the recent conjecture of a second QCD Pomeron related to the conformal spin-1 component is shown to rely upon a strong azimuthal matching of the p= 1 component in gamma* -proton scattering.

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N. Marchal, R. Peschanski. 1999-05-18. Conformal couplings and ``azimuthal matching'' of QCD Pomerons. https://doi.org/10.1007/s100520000351

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