A Lattice Study of the Two-photon Decay Widths for Scalar and Pseudo-scalar Charmonium

Abstract

In this exploratory study, two photon decay widths of pseudo-scalar (${\eta }_c$) and scalar (${\chi }_{c0}$) charmonium are computed using two ensembles of $N_f=2$ twisted mass lattice QCD gauge configurations. The simulation is performed two lattice ensembles with lattice spacings $a=0.067$ fm with size $32^3\times 64$ and $a=0.085$ fm with size $24^3\times 48$, respectively. The results for the decay widths for the two charmonia are obtained which are in the right ballpark however smaller than the experimental ones. Possible reasons for these discrepancies are discussed.

arXiv commentversion accepted by Chinese Physics C

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Cited by in corpus (7)

• Precise determination of decay rates for ${\eta }_c\to \gamma \gamma$, $J/\psi \to \gamma {\eta }_c$ and $J/\psi \to {\eta }_c{e}^{+}{e}^{-}$ from lattice QCD
• Two-photon transitions of charmonia on the light front
• Observation of the charmonium decay ${\eta }_c\to \gamma \gamma$ in $J/\psi \to \gamma {\eta }_c$
• Lattice study of $J/\psi \to \gamma {\eta }_c$ using a method without momentum extrapolation
• Self-consistent analysis for the ${\eta }_c\to \gamma \gamma$ process
• Opportunities for studying $C$-even resonances at 3-12 GeV photon collider
• Study of the Magnetic Dipole Transition of $J/\psi \to \gamma {\eta }_c$ via ${\eta }_c\to p\bar{p}$