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arXiv · 0910.5036

Calculation of nucleon strange quark content with dynamical overlap quarks

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

We calculate the nucleon strange quark content directly from disconnected three-point functions. Numerical simulations are carried out in two-flavor QCD using the overlap quark action with up and down quark masses down to a fifth of the physical strange quark mass. To improve the statistical accuracy, we calculate the nucleon two-point functions with the low-mode averaging technique, whereas the all-to-all quark propagator is used for the disconnected quark loop. We obtain the y parameter, which is the ratio of the strange and light quark contents, y = 0.024(45) at the physical point. This is in a good agreement with our earlier calculation from the nucleon spectrum through the Feynman-Hellmann theorem.

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JLQCD collaboration, K. Takeda, S. Aoki, S. Hashimoto, T. Kaneko, T. Onogi, N. Yamada. 2009-10-27. Calculation of nucleon strange quark content with dynamical overlap quarks. https://arxiv.org/abs/0910.5036

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