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arXiv · hep-ph/9506378

Color-Octet $ψ'$ 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 $p_\perp$-integrated $ψ'$ production cross sections in pion-nucleon reactions. The observed polarization of the $ψ'$ is not reproduced by the lowest-order leading-twist color-singlet and color-octet mechanisms. This suggests that there are important quarkonium production mechanisms beyond leading twist.

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Wai-Keung Tang, M. Vänttinen. 1995-06-20. Color-Octet $ψ'$ Production at Low $p_\perp$. https://doi.org/10.1103/physrevd.53.4851

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