Two-loop renormalisation of the quark fields in the presence of four-fermion SMEFT operators

A bstract We compute the contributions of the dimension-6 SMEFT operators involving four third-generation quarks to the two-loop renormalisation of the quark fields and masses. We perform the computations in both the Naive Dimensional Regularisation (NDR) and the Breitenlohner-Maison-‘t Hooft- Veltman (BMHV) schemes, and we present results for all relevant field and mass renormalisation constants in the on-shell and $$ \overline{\mathrm{MS}} $$ MS ¯ schemes. We carefully discuss all scheme choices which affect the final results. This completes the computation of field and mass renormalisation constants relevant for two-loop computations in QCD involving dimension-six SMEFT operators.