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Journal of High Energy Physics

, 2019:202 | Cite as

Two-loop kite master integral for a correlator of two composite vertices

  • S. V. MikhailovEmail author
  • N. Volchanskiy
Open Access
Regular Article - Theoretical Physics
  • 8 Downloads

Abstract

We consider the most general two-loop massless correlator I(n1, n2, n3, n4, n5; x, y; D) of two composite vertices with the Bjorken fractions x and y for arbitrary indices {ni} and space-time dimension D; this correlator is represented by a “kite” diagram. The correlator I({ni}; x, y; D) is the generating function for any scalar Feynman integrals related to this kind of diagrams. We calculate I({ni}; x, y; D) and its Mellin moments in a direct way by evaluating hypergeometric integrals in the α representation. The result for I({ni}; x, y; D) is given in terms of a double hypergeometric series — the Kampé de Férriet function. In some particular but still quite general cases it reduces to a sum of generalized hypergeometric functions 3F2. The Mellin moments can be expressed through generalized Lauricella functions, which reduce to the Kampé de Férriet functions in several physically interesting situations. A number of Feynman integrals involved and relations for them are obtained.

Keywords

NLO Computations QCD Phenomenology 

Notes

Open Access

This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.

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Copyright information

© SISSA, Trieste, Italy 2019

Authors and Affiliations

  1. 1.Bogoliubov Laboratory of Theoretical PhysicsJINRDubnaRussia
  2. 2.Research Institute of PhysicsSouthern Federal UniversityRostov-na-DonuRussia

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