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arXiv · 1808.02909

Production and polarization of prompt $J/\psi$ in the improved color evaporation model using the $k_T$-factorization approach

Vincent Cheung·Ramona Vogt
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Abstract

We calculate the polarization of prompt $J/\psi$ production in the improved color evaporation model at leading order employing the $k_T$-factorization approach. In this paper, we present the polarization parameter $\lambda_\vartheta$ of prompt $J/\psi$ as a function of transverse momentum in $p+p$ and $p$ + A collisions to compare with data in the helicity, Collins-Soper and Gottfried-Jackson frames. We also present calculations of the charmonium production cross sections as a function of rapidity and transverse momentum. This is the first $p_T$-dependent calculation of charmonium polarization in the improved color evaporation model. We find agreement with both charmonium cross sections and polarization measurements.

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Vincent Cheung, Ramona Vogt. 2018-08-08. Production and polarization of prompt $J/\psi$ in the improved color evaporation model using the $k_T$-factorization approach. https://doi.org/10.1103/physrevd.98.114029

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