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arXiv · hep-ph/9603266

Color-Octet $J/ψ$ Production at Low $p_\perp$

Wai-Keung Tang·M. Vänttinen
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Abstract

We study contributions from color-octet quarkonium formation mechanisms to $J/ψ$ hadroproduction at low $p_\perp$. We include transitions of color-octet $c\bar{c}$ states into ``direct'' $J/ψ$ and into $χ_{1,2}$ which decay radiatively into a $J/ψ$. Together with earlier work, this calculation constitutes a complete analysis of $p_\perp$-integrated $J/ψ$ production at leading twist. We find that the leading-twist contribution is not sufficient to reproduce the observed production rates and polarization of the $J/ψ$ and $χ_{1,2}$. Hence there must exist other important quarkonium production mechanisms at low $p_\perp$.

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Wai-Keung Tang, M. Vänttinen. 1996-03-11. Color-Octet $J/ψ$ Production at Low $p_\perp$. https://doi.org/10.1103/physrevd.54.4349

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