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arXiv · 1010.5483

One loop matching factors for improved staggered four-fermion operators with improved glue

Jongjeong Kim·Weonjong Lee·Stephen R. Sharpe
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Abstract

We present results for matching factors for staggered four-fermion operators constructed using HYP-smeared fat links both in the action and the operators. We use perturbation theory to calculate the matching factors and work to one-loop order. The new feaure of this work is the use of the Symanzik-improved gauge action, as opposed to the Wilson gauge action. Our results are needed for our ongoing calculation of weak matrix elements using HYP-smeared staggered valence quarks and operators on MILC lattices. We give explicit results for matching factors of the operator needed to calculate $B_K$. We compare the impact of the improvement of the gauge action on one-loop coefficients with that of mean-field improvement of the operators.

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Jongjeong Kim, Weonjong Lee, Stephen R. Sharpe. 2010-10-26. One loop matching factors for improved staggered four-fermion operators with improved glue. https://arxiv.org/abs/1010.5483

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