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arXiv · 1012.2887

Puzzles in charmonium decays

Qiang Zhao
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Abstract

The open charm effects via intermediate hadron loop transitions seem to play a crucial role in the understanding of several existing "puzzles" in charmonium exclusive decays, such as the $\psi(3770)$ non-$D\bar{D}$ decays, and "$\rho\pi$ puzzle" etc. In the charmonium energy region, non-perturbative mechanisms could be still sizeable, and as a consequence the intermediate hadron loop transitions also provide a mechanism for the helicity-selection-rule (HSR) violation. We report our recent progress on those existing puzzles.

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Qiang Zhao. 2010-12-13. Puzzles in charmonium decays. https://doi.org/10.1016/j.nuclphysbps.2010.10.088

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