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Expanding running coupling effects in the hard Pomeron

M. Ciafaloni·D. Colferai·G. P. Salam·A. M. Stasto
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Abstract

We study QCD hard processes at scales of order k^2 > Lambda^2 in the limit in which the beta-function coefficient - b is taken to be small, but alphas(k) is kept fixed. The (nonperturbative) Pomeron is exponentially suppressed in this limit, making it possible to define purely perturbative high-energy Green's functions. The hard Pomeron exponent acquires diffusion and running coupling corrections which can be expanded in the b parameter and turn out to be dependent on the effective coupling b alphas^2 Y. We provide a general setup for this b-expansion and we calculate the first few terms both analytically and numerically.

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M. Ciafaloni, D. Colferai, G. P. Salam, A. M. Stasto. 2002-05-16. Expanding running coupling effects in the hard Pomeron. https://doi.org/10.1103/physrevd.66.054014

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