Two flavors of dynamical quarks on anisotropic lattices

CP-PACS Collaboration, T. Umeda, S. Aoki, M. Fukugita, K-I. Ishikawa, N. Ishizuka, Y. Iwasaki, K. Kanaya, Y. Kuramashi, V. I. Lesk, Y. Namekawa, M. Okawa, Y. Taniguchi, A. Ukawa, T. Yoshie

Published 2003-02-28, updated 2003-07-27Version 2

We report on our study of two-flavor full QCD on anisotropic lattices using $O(a)$-improved Wilson quarks coupled with an RG-improved glue. The bare gauge and quark anisotropies corresponding to the renormalized anisotropy $\xi=a_s/a_t = 2$ are determined as functions of $\beta$ and $\kappa$, which covers the region of spatial lattice spacings $a_s\approx 0.28$--0.16 fm and $m_{PS}/m_V\approx 0.6$--0.9. The calibrations of the bare anisotropies are performed with the Wilson loop and the meson dispersion relation at 4 lattice cutoffs and 5--6 quark masses. Using the calibration results we calculate the meson mass spectrum and the Sommer scale $r_0$. We confirm that the values of $r_0$ calculated for the calibration using pseudo scalar and vector meson energy momentum dispersion relation coincide in the continuum limit within errors. This work serves to lay ground toward studies of heavy quark systems and thermodynamics of QCD including the extraction of the equation of state in the continuum limit using Wilson-type quark actions.