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Application of heavy-quark effective theory to lattice QCD: III. Radiative corrections to heavy-heavy currents

Junpei Harada·Shoji Hashimoto·Andreas S. Kronfeld·Tetsuya Onogi
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Abstract

We apply heavy-quark effective theory (HQET) to separate long- and short-distance effects of heavy quarks in lattice gauge theory. In this paper we focus on flavor-changing currents that mediate transitions from one heavy flavor to another. We stress differences in the formalism for heavy-light currents, which are discussed in a companion paper, showing how HQET provides a systematic matching procedure. We obtain one-loop results for the matching factors of lattice currents, needed for heavy-quark phenomenology, such as the calculation of zero-recoil form factors for the semileptonic decays $B\to D^{(*)}lν$. Results for the Brodsky-Lepage-Mackenzie scale $q^*$ are also given.

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Junpei Harada, Shoji Hashimoto, Andreas S. Kronfeld, Tetsuya Onogi. 2001-12-20. Application of heavy-quark effective theory to lattice QCD: III. Radiative corrections to heavy-heavy currents. https://doi.org/10.1103/physrevd.65.094514

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