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arXiv · 1212.0227

Non-perturbative Renormalization of Improved Staggered Bilinears

Andrew T. Lytle·Stephen R. Sharpe
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Abstract

We compute Z-factors for general staggered bilinears on fine (a \approx 0.09 fm) MILC ensembles using both asqtad and HYP-smeared valence actions, comparing the results to the predictions of one-loop perturbation theory. This is an extension of previous work on the coarse (a \approx 0.12 fm) MILC ensembles. It provides a laboratory for studying NPR methodology in the staggered context, and is an important stepping stone for fully non-perturbative matching factors in ongoing computations of B_K and other weak matrix elements. We also implement non-exceptional RI/SMOM renormalization conditions using the asqtad action and present first results.

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Andrew T. Lytle, Stephen R. Sharpe. 2012-12-02. Non-perturbative Renormalization of Improved Staggered Bilinears. https://arxiv.org/abs/1212.0227

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