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arXiv · 1504.01630

Improved lattice fermion action for heavy quarks

Yong-Gwi Cho·Shoji Hashimoto·Andreas Jüttner·Takashi Kaneko·Marina Marinkovic·Jun-Ichi Noaki·Justus Tobias Tsang
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Abstract

We develop an improved lattice action for heavy quarks based on Brillouin-type fermions, that have excellent energy-momentum dispersion relation. The leading discretization errors of $O(a)$ and $O(a^2)$ are eliminated at tree-level. We carry out a scaling study of this improved Brillouin fermion action on quenched lattices by calculating the charmonium energy-momentum dispersion relation and hyperfine splitting. We present a comparison to standard Wilson fermions and domain-wall fermions.

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Yong-Gwi Cho, Shoji Hashimoto, Andreas Jüttner, Takashi Kaneko, Marina Marinkovic, Jun-Ichi Noaki, Justus Tobias Tsang. 2015-05-28. Improved lattice fermion action for heavy quarks. https://doi.org/10.1007/jhep05(2015)072

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