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arXiv · 2012.00820

Tensor decomposition for bosonic and fermionic scattering amplitudes

Tiziano Peraro·Lorenzo Tancredi
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Abstract

In this paper, we elaborate on a method to decompose multiloop multileg scattering amplitudes into Lorentz-invariant form factors, which exploits the simplifications that arise from considering four-dimensional external states. We propose a simple and general approach that applies to both fermionic and bosonic amplitudes and allows us to identify a minimal number of physically relevant form factors, which can be related one-to-one to the independent helicity amplitudes. We discuss explicitly its applicability to various four- and five-point scattering amplitudes relevant for LHC physics.

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Tiziano Peraro, Lorenzo Tancredi. 2020-12-01. Tensor decomposition for bosonic and fermionic scattering amplitudes. https://doi.org/10.1103/physrevd.103.054042

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