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arXiv · 0805.1943

Hybrid Charmonium and the $ρ-π$ Puzzle

Leonard S. Kisslinger·Diana Parno·Seamus Riordan
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Abstract

Using the method of QCD Sum Rules, we estimate the energy of the lowest hybrid Charmonium state, and find it to be at the energy of the $Ψ'(2S)$ state, about 600 Mev above the $J/Ψ(1S)$ state. Since our solution is not consistent with a pure hybrid at this energy, we conclude that the $Ψ'(2S)$ state is probably an admixed $c \bar{c}$ and hybrid $c \bar{c}g$ state. From this conjecture we find a possible explanation of the famous $ρ-π$ puzzle.

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Leonard S. Kisslinger, Diana Parno, Seamus Riordan. 2008-11-21. Hybrid Charmonium and the $ρ-π$ Puzzle. https://doi.org/10.1155/2008%2F982341

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