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arXiv · 2307.12112

Pole decomposition of BFKL eigenvalue at zero conformal spin and the real part of digamma function

Mohammad Joubat·Claudelle Capasia Madjuogang Sandeu·Alex Prygarin
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Abstract

We consider the powers of leading order eigenvalue of the Balitsky-Fadin-Kuraev-Lipatov~(BFKL) equation at zero conformal spin. Using reflection identities of harmonic sums we demonstrate how involved generalized polygamma functions are introduced by pole separation of a rather simple digamma function. This generates higher weight generalized polygamma functions at any given order of perturbative expansion. As a byproduct of our analysis we develop a general technique for calculating powers of the real part of digamma function in a pole separated form.

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Mohammad Joubat, Claudelle Capasia Madjuogang Sandeu, Alex Prygarin. 2023-07-22. Pole decomposition of BFKL eigenvalue at zero conformal spin and the real part of digamma function. https://arxiv.org/abs/2307.12112

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