  Matrix elements of heavy-light flavor currents play an important role in
modern particle physics and precise theory predictions are of interest for
phenomenology. Heavy Quark Effective Theory (HQET) is a valuable tool to obtain
such predictions. In the HQET matching program of the ALPHA collaboration
presently only the temporal component of the axial vector current is included.
Extending the matching to the temporal component of the vector current and the
spatial components of the axial vector current thus seems desirable. Here we
present a recent one-loop study in lattice perturbation theory to test two
candidate matching observables for these currents for their quality to guide
future non-perturbative investigations.
