h → γγ and h → Zγ decays in Standard Model Effective Field Theory
2019 August 31
We present the calculation of the h → γγ and h → Zγ decay rates at the one-loop in the Standard Model Effective Field Theory (SMEFT), based on analyses published in refs. [1, 2]. The calculation has been performed including all relevant SMEFT operators up to mass-dimension 6, without resorting to any flavour or CP-conservation assumptions. The expressions for the on-shell amplitudes have been checked to be gauge invariant, renormalisation scale invariant and gauge fixing parameter independent. Final results are presented as compact semi-numerical formulae, easy to use in the interpretation of experimental data or in multi-parameter fits constraining the SMEFT parameters.