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Anisotropic lattice actions for heavy quark

Shoji Hashimoto·Masataka Okamoto
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Abstract

The anisotropic lattice fermion actions are investigated with the one-loop perturbative calculations aiming at constructing a formulation for heavy quark with controlled systematic uncertainties. For the heavy-light systems at rest the anisotropic lattice with small temporal lattice spacing $a_t$ suppresses the discretization error by a power of $a_t m_Q$ for a heavy quark of mass $m_Q$. We discuss the issue of large discretization errors, which scales as $a_s m_Q$ with $a_s$ the spatial lattice spacing. By performing one-loop calculations of the speed-of-light renormalization for several possible lattice actions in the limit of $a_t\to 0$, we show that one can eliminate the large systematic error on the anisotropic lattice.

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Shoji Hashimoto, Masataka Okamoto. 2003-02-20. Anisotropic lattice actions for heavy quark. https://doi.org/10.1103/physrevd.67.114503

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