Two-photon width of eta_c and eta'_c from Heavy-Quark Spin Symmetry

Abstract

We evaluate the two-photon width of the pseudoscalar charmonia, Gamma(eta_c -> gamma gamma) and Gamma(eta'_c -> gamma gamma), within a Heavy-Quark Spin-Symmetry setting and show that whereas the former agrees with experiment, the latter is more than twice larger than the recent measurement by CLEO. When binding-energy effects are included in the eta'_c case, the discrepancy is worse, pointing out at a possible anomaly in the eta'_c decay.

4 pages, 2 figures, Revtex4; v2: discussions enlarged and some references added. The conclusions are unchanged

References in corpus (1)

• Quarkonium Production at High-Energy Hadron Colliders

Cited by in corpus (12)

• Properties of $Q\bar{Q}$ $(Q\epsilon b,c)$ mesons in Coulomb plus Power potential
• Weak productions of new charmonium in semi-leptonic decays of B_c
• $O({\alpha }_s{v}^2)$ Corrections to Hadronic and Electromagnetic Decays of ${}^1{S}_0$ Heavy Quarkonium
• Two Photon Transition Form Factor of $\bar{c}c$ Quarkonia
• Study of charmonia in four-meson final states produced in two-photon collisions
• Di-electron and two-photon widths in charmonium
• Two-photon width of eta_b, eta'_b and eta''_b from Heavy-Quark Spin Symmetry
• η_b and η_c radiative decays in the Salpeter model with the AdS/QCD inspired potential
• The role of meson exchanges in light-by-light scattering
• Study of $B_c^{\ast }$ $\to$ $\psi (1S,2S)P$, ${\eta }_c(1S,2S)P$ weak decays
• Radiative and leptonic decays of the pseudoscalar charmonium state ${\eta }_c$
• Two-photon decay of pseudoscalar quarkonia