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arXiv · nucl-th/9912046

Model for $J/ψ$ absorption in hadronic matter

Ziwei Lin·C. M. Ko
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Abstract

The cross sections for $J/ψ$ absorption by $π$ and $ρ$ mesons are studied in a meson-exchange model that includes not only pseudoscalar-pseudoscalar-vector-meson couplings but also three-vector-meson and four-point couplings. We find that they are much larger than in a previous study where only pseudoscalar-pseudoscalar-vector-meson couplings were considered. Including form factors at interaction vertices, the $J/ψ$ absorption cross sections $σ_{πψ}$ and $σ_{ρψ}$ are found to have values on the order of 7 mb and 3 mb, respectively. Their thermal averages in hadronic matter at temperature T=150 MeV are, respectively, about 1 mb and 2 mb.

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Ziwei Lin, C. M. Ko. 2000-08-21. Model for $J/ψ$ absorption in hadronic matter. https://doi.org/10.1103/physrevc.62.034903

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