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arXiv · 1012.1907

Nucleon strange quark content in 2+1-flavor QCD

JLQCD Collaboration·K. Takeda·S. Aoki·S. Hashimoto·T. Kaneko·T. Onogi·N. Yamada
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Abstract

We calculate the strange quark content of the nucleon directly from its disconnected three-point function in N_f=2+1 QCD. Chiral symmetry is crucial to avoid a possibly large contamination due to operator mixing, and is exactly preserved by employing the overlap quark action. We also use the all-to-all quark propagator and the low-mode averaging technique in order to accurately calculate the relevant nucleon correlator. Our preliminary result extrapolated to the physical point is f_{T_s} = 0.013(12)(16). This is in good agreement with our previous estimate in N_f=2 QCD as well as those from our indirect calculations using the Feynman-Hellmann theorem.

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JLQCD Collaboration, K. Takeda, S. Aoki, S. Hashimoto, T. Kaneko, T. Onogi, N. Yamada. 2010-12-09. Nucleon strange quark content in 2+1-flavor QCD. https://arxiv.org/abs/1012.1907

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