Charmed meson spectra and decay constants with one-loop O(a) improved relativistic heavy quark action☆

We calculate charmed meson spectra and decay constants in lattice QCD employing one-loop O ( a ) improved heavy quark action and axial-vector currents. In quenched simulations at a ∼0.1 fm with the plaquette gauge action as well as a renormalization-group improved one, it is shown that the deviation from the continuum dispersion relation and the violation of space-time symmetry for the pseudoscalar meson decay constants are substantially reduced, once the O ( a ) improvement is applied. Preliminary results with two flavors of dynamical quarks are also presented.