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arXiv · hep-ph/0507106

Dimensional Regularisation and Factorisation Schemes in the BFKL Equation at Subleading Leve

Abstract

We study the anomalous dimensions and coefficient functions generated by the BFKL equation in 4+2 epsilon dimensions, by investigating both running coupling effects, and the inclusion of the full next-to-leading kernel. After generalising the Fourier representation of the solutions to this case, we analyse the beta-dependent renormalisation-group factorisation of anomalous dimension and coefficient contributions to the gluon density. We derive on this basis the normalisation factor of the Q0-scheme with respect to the MSbar-scheme, including beta-dependent corrections to it, and we outline the derivation of the full next-to-leading contributions. We also provide an expression for the resummed gamma_qg in the MSbar-scheme which exhibits its universality and is explicit up to quadratures.

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BibTeXRIS

M. Ciafaloni, D. Colferai. 2005-07-08. Dimensional Regularisation and Factorisation Schemes in the BFKL Equation at Subleading Leve. https://doi.org/10.1088/1126-6708%2F2005%2F09%2F069

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