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arXiv · hep-ph/9508373

Signature for Color-Octet Production of $J/ψ$ in $e^+ e^-$ Annihilation

Eric Braaten·Yu-Qi Chen
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Abstract

The inclusive cross section for the production of $J/ψ$ in $e^+ e^-$ annihilation is studied using a recently developed factorization formalism. In addition to the conventional color-singlet contribution, we include contributions from $c \bar c$ pairs that are produced at short distances in color-octet states. The color-octet contributions are suppressed by the smaller probability for the color-octet $c \bar c$ pair to evolve into a state that includes a $ψ$, but they may dominate near the upper endpoint of the $ψ$ energy spectrum. The signature for the color-octet contribution is a dramatic change in the angular distribution of the $ψ$ near the endpoint.

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Eric Braaten, Yu-Qi Chen. 1995-11-22. Signature for Color-Octet Production of $J/ψ$ in $e^+ e^-$ Annihilation. https://doi.org/10.1103/physrevlett.76.730

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