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arXiv · 1710.09011

Proton mass decomposition

Yi-Bo Yang·Ying Chen·Terrence Draper·Jian Liang·Keh-Fei Liu
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Abstract

We report the results on the proton mass decomposition and also on the related quark and glue momentum fractions. The results are based on overlap valence fermions on four ensembles of $N_f = 2+1$ DWF configurations with three lattice spacings and volumes, and several pion masses including the physical pion mass. With 1-loop perturbative calculation and proper normalization of the glue operator, we find that the $u, d,$ and $s$ quark masses contribute 9(2)\% to the proton mass. The quark energy and glue field energy contribute 31(5)\% and 37(5)\% respectively in the $\overline{MS}$ scheme at $\mu = 2$ GeV. The trace anomaly gives the remaining 23(1)\% contribution. The $u,d,s$ and glue momentum fractions in the $\overline{MS}$ scheme are consistent with the global analysis at $\mu = 2$ GeV.

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Yi-Bo Yang, Ying Chen, Terrence Draper, Jian Liang, Keh-Fei Liu. 2017-10-24. Proton mass decomposition. https://doi.org/10.1051/epjconf%2F201817514002

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