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arXiv · 0904.1604

Annihilation Rate of $2^{++}$ Charmonium and Bottomonium

Guo-Li Wang
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Abstract

Two-photon annihilation rates of $2^+$ tensor charmonium and bottomonium up to third radial excited states are estimated in the relativistic Salpeter method. Full Salpeter equation for $2^+$ tensor state is solved with a well defined relativistic wave function and we calculated the annihilation amplitude using the Mandelstam formalism. Our estimates of the decay widths are: $Γ(χ_{c2} \to 2γ)=501$ eV, $Γ(χ'_{c2} \to 2γ)=534$ eV, $Γ(χ_{b2} \to 2γ)=7.4$ eV and $Γ(χ'_{b2} \to 2γ)=7.7$ eV. We also give total decay widths of the lowest states estimated by the two-gluon decay rates, and the results are: $Γ_{tot}(χ_{c2})=2.64$ MeV, $Γ_{tot}(χ_{b2})=0.220$ MeV and $Γ_{tot}(χ'_{b2})=0.248$ MeV.

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Guo-Li Wang. 2009-04-09. Annihilation Rate of $2^{++}$ Charmonium and Bottomonium. https://doi.org/10.1016/j.physletb.2009.03.030

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