We present a strategy how to match the full set of components of the heavylight axial and vector currents in Heavy Quark Effective Theory (HQET), up to and including 1/m h-corrections, to QCD. While the ultimate goal is to apply these matching conditions non-perturbatively, in this study we first have implemented them at tree-level, in order to find good choices of the matching observables with small O(1/m 2 h) contributions. They can later be employed in the non-perturbative matching procedure which is a crucial part of precision HQET computations of semileptonic decay form factors in lattice QCD.

Heavy Quark Effective Theory (HQET) computations of semi-leptonic decays, e.g. B → πlν, require the knowledge of the parameters in the effective theory for all components of the heavy-light flavor currents. So far non-perturbative matching conditions have been employed only for the time component of the axial current. Here we perform a check of matching conditions for the time component of the vector current and the spatial component of the axial vector current up to one-loop order of perturbation theory and to lowest order of the 1/m-expansion. We find that the proposed observables have small higher order terms in the 1/m-series and are thus excellent candidates for a nonperturbative matching procedure.

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We present the pastor software package for automated lattice perturbation theory calculations in the Schrödinger functional scheme. We discuss automatic diagram and vertex generation and present an example calculation involving correlation functions using both the heavy quark effective theory (HQET) action including 1/m corrections and the O(a)-improved Wilson action.

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