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arXiv · 1202.3026

Updated study of the $η_c$ and $η_c^\prime$ decays into light vector mesons

Qian Wang·Xiao-Hai Liu·Qiang Zhao
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Abstract

We re-investigate the exclusive decays of $η_c$ and $η_c^\prime$ to a pair of light vector mesons, i.e. $η_c (η_c')\to VV$. The long-distance intermediate meson loop (IML) effects are evaluated as a non-perturbative mechanism in addition to the short-distance $c\bar{c}$ annihilation contributions. We show that both processes can be reasonably well constrained with the help of the available experimental data. Since $η_c$ and $η_c'$ are the spin-0 partners of $J/ψ$ and $ψ'$, respectively, our study is useful for gaining insights into the pQCD helicity selection rule violations in charmonium decays and the long-standing "$ρπ$ puzzle".

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Qian Wang, Xiao-Hai Liu, Qiang Zhao. 2012-03-27. Updated study of the $η_c$ and $η_c^\prime$ decays into light vector mesons. https://doi.org/10.1016/j.physletb.2012.04.022

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