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arXiv · 2307.02888

Pion PDFs confronted by Fixed-Target Charmonium Production

Wen-Chen Chang·Chia-Yu Hsieh·Yu-Shiang Lian·Jen-Chieh Peng·Stephane Platchkov·Takahiro Sawada
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Abstract

The pion, as the Goldstone boson of the strong interaction, is the lightest QCD bound state and responsible for the long-range nucleon-nucleon interaction inside the nucleus. Our knowledge on the pion partonic structure is limited by the existing Drell-Yan data which are primarily sensitive to the pion valence-quark distributions. The recent progress of global analysis of pion's parton distribution functions (PDFs) utilizing various experimental approaches are introduced. From comparisons between the pion-induced $J/\psi$ and $\psi(2S)$ production data with theoretical calculations using the CEM and NRQCD models, we show how these charmonium production data could provide useful constraints on the pion PDFs.

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Wen-Chen Chang, Chia-Yu Hsieh, Yu-Shiang Lian, Jen-Chieh Peng, Stephane Platchkov, Takahiro Sawada. 2023-07-06. Pion PDFs confronted by Fixed-Target Charmonium Production. https://doi.org/10.1007/s43673-023-00085-4

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