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

TL;DR

This study uses 2+1 flavor lattice QCD with PACS-CS configurations to analyze charm quark systems, providing preliminary results on spectra and decay constants, and exploring quark mass dependences.

Contribution

It presents the first lattice QCD results for charm quark systems using the PACS-CS configurations with a relativistic heavy quark action.

Findings

Preliminary charmonium spectrum obtained.

Decay constants for D and D_s mesons evaluated.

Hyperfine and orbital splittings depend on dynamical quark masses.

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.