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arXiv · hep-lat/0110112

Is the Up Quark Massless?

Daniel R. Nelson·George T. Fleming·Greg W. Kilcup
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Abstract

Several lattice calculations of a combination of the low energy constants of the chiral Lagrangian, 2α_8-α_5, are presented. This combination is critical for the preclusion of a massless up quark. The result found is 2α_8-α_5 = 0.115 \pm 0.051^{stat} \pm 0.25^{syst}, which is well outside of the range allowed by a massless up quark.

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Daniel R. Nelson, George T. Fleming, Greg W. Kilcup. 2001-10-15. Is the Up Quark Massless?. https://doi.org/10.1016/s0920-5632(01)01669-3

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