Heavy-quark physics with a tmQCD valence action

Abstract

We introduce a mixed-action approach based on CLS ensembles, where a valence Nf=2+1+1 Twisted Mass QCD action is combined with the Nf=2+1 non-perturbatively O(a)-improved Wilson sea sector. We show that for maximally twisted valence quarks, the automatic O(a)improvement of this set-up holds up to lattice artifacts coming from sea quark mass effects. Furthermore, we introduce a three-dimensional Gradient Flow smearing in order to tame the signal to noise ratio problem.