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arXiv · hep-ph/9706422

O(N_fα^2) Corrections to Muon Decay

Robin G. Stuart
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Abstract

The calculation of the $O(N_fα^2)$ corrections to muon decay is described. These are the 2-loop diagrams containing a massless fermion loop and they form an important gauge-invariant subclass. It is shown that all such diagrams can be expressed in terms of a universal master integral. We focus on the calculation of box diagrams and in particular on the removal of their infrared divergences.

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Robin G. Stuart. 1997-06-19. O(N_fα^2) Corrections to Muon Decay. https://arxiv.org/abs/hep-ph/9706422

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