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arXiv · 1302.5668

Gauge invariance at work in FDR: H -> gamma gamma

A. Donati·R. Pittau
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Abstract

We present the first complete calculation performed within the Four Dimensional Regularization scheme (FDR), namely the loop-induced on-shell amplitude for the Higgs boson decay into two photons in an arbitrary R_csi gauge. FDR is a new technique -free of infinities- for addressing multi-loop calculus, which automatically preserves gauge invariance, allowing for a 4-dimensional computation at the same time. We obtained the same result as that assessed in dimensional regularization, thereby explicitly verifying, in a realistic case, that FDR respects gauge invariance.

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A. Donati, R. Pittau. 2013-02-22. Gauge invariance at work in FDR: H -> gamma gamma. https://doi.org/10.1007/jhep04(2013)167

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