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arXiv · hep-lat/9301005

The Heavy Quark Self-Energy in Nonrelativistic Lattice QCD

Colin J. Morningstar
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Abstract

The heavy quark self-energy in nonrelativistic lattice QCD is calculated to $O(α_s)$ in perturbation theory. An action which includes all spin-independent relativistic corrections to order $v^2$, where $v$ is the typical heavy quark velocity, and all spin-dependent corrections to order $v^4$ is used. The standard Wilson action and an improved multi-plaquette action are used for the gluons. Results for the mass renormalization, wavefunction renormalization, and energy shift are given; tadpole contributions are found to be large. A tadpole improvement scheme in which all link variables are rescaled by a mean-field factor is also studied. The effectiveness of this scheme in offsetting the large tadpole contributions to the heavy quark renormalization parameters is demonstrated.

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BibTeXRIS

Colin J. Morningstar. 1993-01-15. The Heavy Quark Self-Energy in Nonrelativistic Lattice QCD. https://doi.org/10.1103/physrevd.48.2265

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