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On the 2nd Order Corrections to the Hard Pomeron and the Running Coupling Constant

N. Armesto·J. Bartels·M. A. Braun
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Abstract

It is shown that solutions to the 2nd order BFKL eigenvalue equation exist for arbitrary large real values of the complex angular momentum $j$. This corresponds to a cut in the complex $j$ plane along the whole real axis, and it makes the use of the complex angular momentum variable for the calculation of the high-energy behavior somewhat questionable. The eigenfunctions contain non-perturbative pieces which behave as $\exp(-1/α_s b)$ and have no counterpart in the leading-log BFKL equation. The high-energy behavior of the 2nd order BFKL Green function as found by other authors, is reproduced by excluding these non-perturbative pieces of the eigenfunctions.

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N. Armesto, J. Bartels, M. A. Braun. 1998-08-17. On the 2nd Order Corrections to the Hard Pomeron and the Running Coupling Constant. https://doi.org/10.1016/s0370-2693(98)01284-2

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