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arXiv · 1307.7741

Computing the full two-loop gluon Regge trajectory within Lipatov's high energy effective action

Abstract

We discuss computational details of our recent result, namely, the first derivation of the two-loop gluon Regge trajectory within the framework of Lipatov's high energy effective action. In particular, we elaborate on the direct evaluation of Feynman two-loop diagrams by using the Mellin-Barnes representations technique. Our result is in precise agreement with previous computations in the literature, providing this way a highly non-trivial test of the effective action and the proposed subtraction and renormalization scheme combined with our approach for the treatment of the loop diagrams.

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G. Chachamis, M. Hentschinski, J. D. Madrigal, A. Sabio Vera. 2013-07-29. Computing the full two-loop gluon Regge trajectory within Lipatov's high energy effective action. https://arxiv.org/abs/1307.7741

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