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arXiv · hep-ph/0311003

Belle J/psi+eta_c anomaly and a very light scalar boson

Kingman Cheung·Wai-Yee Keung
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Abstract

The large rate of the $J/ψ+η_c$ production observed by the Belle collaboration has posed a serious challenge to our understanding of the quarkonium. We examine a scenario that there exists a light scalar boson around 5 GeV, with an enhanced coupling solely to the charm quark. Such a scenario would explain the Belle anomaly. It also predicts a significant increase in $J/ψ$ plus open charm pair production. An immediate test for the scalar boson is to look for a peak around 5 GeV in the recoil mass spectrum of $J/ψ$, because the scalar boson can also be produced in association with the $J/ψ$. Finally, we also point out that the process $e^+ e^- \to H γ$ is sizable for observation.

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Kingman Cheung, Wai-Yee Keung. 2003-11-01. Belle J/psi+eta_c anomaly and a very light scalar boson. https://doi.org/10.1103/physrevd.69.094026

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