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arXiv · hep-ph/9612425

Hard diffractive electroproduction, transverse momentum distribution and QCD vacuum structure

Igor Halperin·Ariel Zhitnitsky
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Abstract

We study the impact of the "intrinsic" hadron transverse momentum on the pre-asymptotic behavior of the diffractive electroproduction of longitudinally polarized $ ρ$-meson. Surprisingly, we find the onset of the asymptotic regime in this problem to be rather low, Q^2 ~ 10 GeV^2 where power corrections due to the transverse momentum do not exceed 20 % in the amplitude. This drastically contrasts with exclusive amplitudes where the asymptotics starts at much higher Q^2 = 50 - 100 GeV^2. The sources of such unexpected behavior are traced back to some general (the quark-hadron duality) as well as more silent (properties of higher dimensional vacuum condensates) features of QCD.

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Igor Halperin, Ariel Zhitnitsky. 1996-12-20. Hard diffractive electroproduction, transverse momentum distribution and QCD vacuum structure. https://doi.org/10.1103/physrevd.56.184

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