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arXiv · hep-lat/0611033

First Nonperturbative Test of a Relativistic Heavy Quark Action in Quenched Lattice QCD

Y. Kayaba·S. Aoki·M. Fukugita·Y. Iwasaki·K. Kanaya·Y. Kuramashi·M. Okawa·A. Ukawa·T. Yoshie
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Abstract

We perform a numerical test of a relativistic heavy quark(RHQ) action, recently proposed by Tsukuba group, in quenched lattice QCD at $a\simeq 0.1$ fm. With the use of the improvement parameters previously determined at one-loop level for the RHQ action, we investigate a restoration of rotational symmetry for heavy-heavy and heavy-light meson systems around the charm quark mass. We focused on two quantities, the meson dispersion relation and the pseudo-scalar meson decay constants. It is shown that the RHQ action significantly reduces the discretization errors due to the charm quark mass. We also calculate the S-state hyperfine splittings for the charmonium and charmed-strange mesons and the $D_s$ meson decay constant. The remaining discretization errors in the physical quantities are discussed.

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Y. Kayaba, S. Aoki, M. Fukugita, Y. Iwasaki, K. Kanaya, Y. Kuramashi, M. Okawa, A. Ukawa, T. Yoshie. 2007-02-08. First Nonperturbative Test of a Relativistic Heavy Quark Action in Quenched Lattice QCD. https://doi.org/10.1088/1126-6708%2F2007%2F02%2F019

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