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Perturbative calculation of O(a) improvement coefficients

Junpei Harada·Shoji Hashimoto·Andreas S. Kronfeld·Tetsuya Onogi
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Abstract

We compute several coefficients needed for O(a) improvement of currents in perturbation theory, using the Brodsky-Lepage-Mackenzie prescription for choosing an optimal scale q*. We then compare the results to non-perturbative calculations. Normalization factors of the vector and axial vector currents show good agreement, especially when allowing for small two-loop effects. On the other hand, there are large discrepancies in the coefficients of O(a) improvement terms. We suspect that they arise primarily from power corrections inherent in the non-perturbative methods.

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Junpei Harada, Shoji Hashimoto, Andreas S. Kronfeld, Tetsuya Onogi. 2002-08-01. Perturbative calculation of O(a) improvement coefficients. https://doi.org/10.1103/physrevd.67.014503

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