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arXiv · 0810.2364

Charm quark system in 2+1 flavor lattice QCD using the PACS-CS configurations

CS Collaboration·Y. Namekawa·S. Aoki·D. Kadoh·N. Ishii·K. -I. Ishikawa·N. Ishizuka·T. Izubuchi·K. Kanaya·Y. Kuramashi·M. Okawa·Y. Taniguchi·A. Ukawa·N. Ukita·T. Yoshie
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Abstract

We study heavy-heavy and heavy-light quark systems for charm with a relativistic heavy quark action in 2+1 flavor lattice QCD. Configurations are generated by the PACS-CS Collaboration at the lattice spacing is $a=0.09$ fm with the lattice size of $32^3\times 64$ employing the $O(a)$-improved Wilson quark action and the Iwasaki gauge action. We present preliminary results for the charmonium spectrum and the $D$ and $D_s$ meson decay constants evaluated at 3.5 MeV$< m_{\rm ud}<$ 12 MeV with $m_{\rm s}$ around the physical value. We investigate the dynamical quark mass dependences of the hyperfine and the orbital splittings. The decay constants are compared with the recent experimental values.

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CS Collaboration, Y. Namekawa, S. Aoki, D. Kadoh, N. Ishii, K. -I. Ishikawa, N. Ishizuka, T. Izubuchi, K. Kanaya, Y. Kuramashi, M. Okawa, Y. Taniguchi, A. Ukawa, N. Ukita, T. Yoshie. 2008-10-14. Charm quark system in 2+1 flavor lattice QCD using the PACS-CS configurations. https://arxiv.org/abs/0810.2364

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