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O(a)-improved quark action on anisotropic lattices and perturbative renormalization of heavy-light currents

Junpei Harada·Andreas S. Kronfeld·Hideo Matsufuru·Noriaki Nakajima·Tetsuya Onogi
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Abstract

We investigate the Symanzik improvement of the Wilson quark action on anisotropic lattices. Taking first a general action with nearest-neighbor and clover interactions, we study the mass dependence of the ratio of the hopping parameters, the clover coefficients, and an improvement coefficient for heavy-light vector and axial vector currents. We show how tree-level improvement can be achieved. For a particular choice of the spatial Wilson coupling, the results simplify, and $O(m_0a_τ)$ improvement is possible. (Here $m_0$ is the bare quark mass and $a_τ$ the temporal lattice spacing.) With this choice we calculate the renormalization factors of heavy-light bilinear operators at one-loop order of perturbation theory employing the standard plaquette gauge action.

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Junpei Harada, Andreas S. Kronfeld, Hideo Matsufuru, Noriaki Nakajima, Tetsuya Onogi. 2001-03-23. O(a)-improved quark action on anisotropic lattices and perturbative renormalization of heavy-light currents. https://doi.org/10.1103/physrevd.64.074501

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