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A Perturbative Determination of Mass Dependent $O(a)$ Improvement Coefficients in a Relativistic Heavy Quark Action

Sinya Aoki·Yasuhisa Kayaba·Yoshinobu Kuramashi
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Abstract

We present the results for a perturbative determination of mass dependent improvement coefficients $ν$, $r_s$, $c_E$ and $c_B$ in a relativistic heavy quark action, which we have designed to control $m_Qa$ errors by extending the on-shell $O(a)$ improvement program to the case of $m_Q \gg Λ_{\rm QCD}$, where $m_Q$ is the heavy quark mass. The parameters $ν$ and $r_s$ are determined from the quark propagator and $c_E$ and $c_B$ are from the on-shell quark-quark scattering amplitude. We show that all the parameters, together with the quark wave function and the mass renormalization factors, are determined free from infrared divergences once their tree level values are properly tuned. Results of these parameters are shown as a function of $m_Q a$ for various improved gauge actions.

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Sinya Aoki, Yasuhisa Kayaba, Yoshinobu Kuramashi. 2003-09-25. A Perturbative Determination of Mass Dependent $O(a)$ Improvement Coefficients in a Relativistic Heavy Quark Action. https://doi.org/10.1016/j.nuclphysb.2004.07.017

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