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arXiv · 1804.01483

First direct lattice-QCD calculation of the $x$-dependence of the pion parton distribution function

Jian-Hui Zhang·Jiunn-Wei Chen·Luchang Jin·Huey-Wen Lin·Andreas Schäfer·Yong Zhao
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Abstract

We present the first direct lattice-QCD calculation of the Bjorken-$x$ dependence of the valence quark distribution of the pion. Using large-momentum effective theory (LaMET), we calculate the boosted pion state with long Wilson link operators. After implementing the one-loop matching and meson mass corrections, our result at $m_π\approx 310$ MeV is in agreement with those extracted from experimental data as well as from Dyson-Schwinger equation in small $x$ region, but a sizeable discrepancy in the large $x$ region. This discrepancy provides a nice opportunity to systematically study and disentangle the artifacts in the LaMET approach, which will eventually help to discern various existing analyses in the literature.

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Jian-Hui Zhang, Jiunn-Wei Chen, Luchang Jin, Huey-Wen Lin, Andreas Schäfer, Yong Zhao. 2019-07-31. First direct lattice-QCD calculation of the $x$-dependence of the pion parton distribution function. https://doi.org/10.1103/physrevd.100.034505

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