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arXiv · 1106.4629

Z-Sum Approach to Loop Integrals using Taylor Expansion

Paulo A. Rottmann·Laura Reina
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Abstract

We study the applicability of the Z-Sum approach to multi-loop calculations with massive particles in perturbative quantum field theory. We systematically analyze the case of one-loop scalar integrals, which represent the building blocks of any higher-loop calculation. We focus in particular on triangle one-loop integrals and identify strengths and limitations of the Z-Sum approach, extending our results to the case of one-loop box integrals when appropriate. We conclude with the calculation of a specific physical example: the calculation of heavy-flavor corrections to deep-inelastic-scattering structure functions.

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Paulo A. Rottmann, Laura Reina. 2011-07-12. Z-Sum Approach to Loop Integrals using Taylor Expansion. https://doi.org/10.1007/jhep09(2011)033

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