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arXiv · 2003.14128

Valence-Quark Distribution of the Kaon and Pion from Lattice QCD

Huey-Wen Lin·Jiunn-Wei Chen·Zhouyou Fan·Jian-Hui Zhang·Rui Zhang
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Abstract

We present the first lattice-QCD calculation of the kaon valence-quark distribution functions using the large-momentum effective theory (LaMET) approach. The calculation is performed with multiple pion masses with the lightest one around 220 MeV, 2 lattice spacings $a=0.06$ and 0.12 fm, $(M_\pi)_\text{min} L \approx 5.5$, and high statistics ranging from 11,600 to 61,312 measurements. We also calculate the valence-quark distribution of pion and find it to be consistent with the FNAL E615 experimental results, and our ratio of the $u$ quark PDF in the kaon to that in the pion agrees with the CERN NA3 experiment. We also make predictions of the strange-quark distribution of the kaon.

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Huey-Wen Lin, Jiunn-Wei Chen, Zhouyou Fan, Jian-Hui Zhang, Rui Zhang. 2020-03-31. Valence-Quark Distribution of the Kaon and Pion from Lattice QCD. https://doi.org/10.1103/physrevd.103.014516

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