An Improved Action for Heavy Quarks

Andreas S. Kronfeld; Mehmet B. Oktay

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arXiv · hep-lat/0610069

An Improved Action for Heavy Quarks

Andreas S. Kronfeld·Mehmet B. Oktay

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Abstract

We extend the Fermilab method for heavy quarks to include all interactions of dimension six in the action. We discuss a subtlety in the power counting, which implies that, for heavy quarks, certain interactions of dimension seven are commensurate with some of those of dimension six. We then present tree-level matching conditions obtained from calculating the Compton scattering amplitude for (lattice) QCD. When the matching conditions have been applied, the improved action removes (tree-level) discretization errors of order $a^2\bm{p}^3/m_Q$ and $a^3\bm{p}^3$.

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Andreas S. Kronfeld, Mehmet B. Oktay. 2006-10-10. An Improved Action for Heavy Quarks. https://arxiv.org/abs/hep-lat/0610069

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