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arXiv · 0711.3590

Master Integrals for Fermionic Contributions to Massless Three-Loop Form Factors

G. Heinrich·T. Huber·D. Maitre
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Abstract

In this letter we continue the calculation of master integrals for massless three-loop form factors by giving analytical results for those integrals which are relevant for the fermionic contributions proportional to N_F^2, N_F*N, and N_F/N. Working in dimensional regularisation, we express one of the integrals in a closed form which is exact to all orders in epsilon, containing Gamma-functions and hypergeometric functions of unit argument. In all other cases we derive multiple Mellin-Barnes representations from which the coefficients of the Laurent expansion in epsilon are extracted in an analytical form. To obtain the finite part of the three-loop quark and gluon form factors, all coefficients through transcendentality six in the Riemann zeta-function have to be included.

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G. Heinrich, T. Huber, D. Maitre. 2008-03-27. Master Integrals for Fermionic Contributions to Massless Three-Loop Form Factors. https://doi.org/10.1016/j.physletb.2008.03.028

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