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arXiv · 0901.4749

J/ψpolarization in photo-production up-to the next-to-leading order of QCD

Chao-Hsi Chang·Rong Li·Jian-Xiong Wang
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Abstract

We investigate the J/psi polarization in photoproduction at the Hadron Electron Ring Accelerator(HERA) up to the next-to-leading order of QCD. The results show that the transverse momentum p_t and energy fraction z distributions of J/psi production do not agree with the observed ones very well. The theoretical uncertainties for the z distributions of the J/psi polarization parameters with respect to various choices of the renormalization and factorization scales are too large to give an accurate prediction. The uncertainties for the p_t distributions of these parameters are small when p_t>3GeV and the obtained p_t distributions can not describe the experimental data even in this region.

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Chao-Hsi Chang, Rong Li, Jian-Xiong Wang. 2009-10-02. J/ψpolarization in photo-production up-to the next-to-leading order of QCD. https://doi.org/10.1103/physrevd.80.034020

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