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arXiv · 0710.0017

Improvement of the pion spectrum with HYP-smeared staggered fermions

Taegil Bae·David Adams·Chulwoo Jung·Hyung-Jin Kim·Jongjeong Kim·Kwangwoo Kim·Weonjong Lee·Stephen R. Sharpe
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Abstract

We extend our previous study of taste-symmetry breaking using HYP-smeared staggered fermions in two ways. First, we improve the statistics of a comparison of unimproved and HYP-smeared staggered fermions on quenched lattices with $a\approx 0.1 $fm. This allows us to obtain a signal for all pion tastes, rather than just a subset, and thus to make a complete comparison. In addition, it allows us to differentiate between wall and local sources. Second, we compare HYP-smeared valence quarks to asqtad valence quarks on 2+1 flavor unquenched MILC lattices. We find that taste breaking is substantially reduced by HYP-smearing, bringing the size of this discretization effect (which is the dominant such effect with staggered fermions) down to the size expected generically for any fermion type.

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Taegil Bae, David Adams, Chulwoo Jung, Hyung-Jin Kim, Jongjeong Kim, Kwangwoo Kim, Weonjong Lee, Stephen R. Sharpe. 2007-09-28. Improvement of the pion spectrum with HYP-smeared staggered fermions. https://arxiv.org/abs/0710.0017

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