Perturbative Matching of Heavy-Light Currents with NRQCD Heavy Quarks

Lattice studies of hadronic matrix elements require matching between operators in full continuum QCD and those in the lattice theory being simulated. In the present article we will focus on an effective lattice theory which combines nonrelativistic (NRQCD) heavy quarks and clover light quarks. We wish to match the theories correct through O( p M , α p M , α ap). For heavy meson (e.g. B and B∗) leptonic and semileptonic decays, the relevant operators are heavy-light vector and axial vector currents, denoted in the continuum theory as Vμ ≡ qγμh and Aμ ≡ qγ5γμh. The first question that arises concerns the number and type of operators required in the effective theory.