Flavour symmetries in the SMEFT

Darius A Faroughy, Gino Isidori, Felix Wilsch, Kei Yamamoto
2020
We analyse how U(3)5 and U(2)5 flavour symmetries act on the Standard Model Effective Field Theory, providing an organising principle to classify the large number of dimension-six operators involving fermion fields. A detailed counting of such operators, at different order in the breaking terms of both these symmetries, is presented. A brief discussion about possible deviations from these two reference cases, and a simple example of the usefulness of this classification scheme for high-pT
more » ... e for high-pT analyses at the LHC, are also presented. Abstract: We analyse how U(3) 5 and U(2) 5 flavour symmetries act on the Standard Model Effective Field Theory, providing an organising principle to classify the large number of dimension-six operators involving fermion fields. A detailed counting of such operators, at different order in the breaking terms of both these symmetries, is presented. A brief discussion about possible deviations from these two reference cases, and a simple example of the usefulness of this classification scheme for high-p T analyses at the LHC, are also presented.
doi:10.5167/uzh-190823 fatcat:l3fc3s5dijezviajjkx5yekq2u