${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$  Decay Mode Summary INSPIRE   PDGID:
M026.31
Mode (*) Fraction ($\Gamma_i$ / $\Gamma$) Scale Factor/
Conf. Level		 P(MeV/c)  
$\Gamma_{59}$ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}}$ ($1.66$ $\pm0.13$) $ \times 10^{-4}$ S=1.2  1492
Category: Radiative decays
The following data is related to the above value:
 ▸ expand all datablocks
$\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}})$
$\Gamma_{59}$
$\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit \eta}^{\,'}{(958)}}{{\mathit \pi}}{{\mathit \pi}})$ ${\times }$ $\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}})/\Gamma_{\text{total}}$
$\Gamma_{1}\Gamma_{59}/\Gamma$
$\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit \rho}}{{\mathit \rho}})$ ${\times }$ $\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}})/\Gamma_{\text{total}}$
$\Gamma_{4}\Gamma_{59}/\Gamma$
$\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit K}^{*}{(892)}}{{\overline{\mathit K}}^{*}{(892)}})$ ${\times }$ $\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}})/\Gamma_{\text{total}}$
$\Gamma_{6}\Gamma_{59}/\Gamma$
$\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit \phi}}{{\mathit \phi}})$ ${\times }$ $\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}})/\Gamma_{\text{total}}$
$\Gamma_{9}\Gamma_{59}/\Gamma$
$\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit \omega}}{{\mathit \omega}})$ ${\times }$ $\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}})/\Gamma_{\text{total}}$
$\Gamma_{16}\Gamma_{59}/\Gamma$
$\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit \omega}}{{\mathit \phi}})$ ${\times }$ $\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}})/\Gamma_{\text{total}}$
$\Gamma_{17}\Gamma_{59}/\Gamma$
$\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit f}_{{{2}}}{(1270)}}{{\mathit f}_{{{2}}}{(1270)}})$ ${\times }$ $\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}})/\Gamma_{\text{total}}$
$\Gamma_{18}\Gamma_{59}/\Gamma$
$\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit f}_{{{2}}}{(1270)}}{{\mathit f}_{{{2}}}^{\,'}{(1525)}})$ ${\times }$ $\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}})/\Gamma_{\text{total}}$
$\Gamma_{19}\Gamma_{59}/\Gamma$
$\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit K}}{{\overline{\mathit K}}}{{\mathit \pi}})$ ${\times }$ $\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}})/\Gamma_{\text{total}}$
$\Gamma_{37}\Gamma_{59}/\Gamma$
$\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit K}^{+}}{{\mathit K}^{-}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}})$ ${\times }$ $\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}})/\Gamma_{\text{total}}$
$\Gamma_{41}\Gamma_{59}/\Gamma$
$\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit K}^{+}}{{\mathit K}^{-}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{0}})$ ${\times }$ $\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}})/\Gamma_{\text{total}}$
$\Gamma_{42}\Gamma_{59}/\Gamma$
$\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ 2( ${{\mathit K}^{+}}{{\mathit K}^{-}}))$ ${\times }$ $\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}})/\Gamma_{\text{total}}$
$\Gamma_{45}\Gamma_{59}/\Gamma$
$\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ 2( ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}))$ ${\times }$ $\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}})/\Gamma_{\text{total}}$
$\Gamma_{48}\Gamma_{59}/\Gamma$
$\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit p}}{{\overline{\mathit p}}})$ ${\times }$ $\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}})/\Gamma_{\text{total}}$
$\Gamma_{51}\Gamma_{59}/\Gamma$
$\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}})/\Gamma_{\text{total}}$
$\Gamma_{59}/\Gamma$
$\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit p}}{{\overline{\mathit p}}})/\Gamma_{\text{total}}{\times }$ $\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}})/\Gamma_{\text{total}}$
$\Gamma_{51}/\Gamma{\times }\Gamma_{59}/\Gamma$
$\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}})/\Gamma_{\text{total}}{\times }$ $\Gamma($ ${{\mathit J / \psi}{(1S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \eta}_{{{c}}}{(1S)}})/\Gamma_{\text{total}}$
$\Gamma_{59}/\Gamma{\times }\Gamma^{{{\mathit J / \psi}{(1S)}}}_{237}/\Gamma^{{{\mathit J / \psi}{(1S)}}}$
$\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}})/\Gamma_{\text{total}}{\times }$ $\Gamma($ ${{\mathit B}^{+}}$ $\rightarrow$ ${{\mathit \eta}_{{{c}}}}{{\mathit K}^{+}})/\Gamma_{\text{total}}$
$\Gamma_{59}/\Gamma{\times }\Gamma^{{{\mathit B}^{\pm}}}_{254}/\Gamma^{{{\mathit B}^{\pm}}}$
$\Gamma($ ${{\mathit \eta}_{{{c}}}{(1S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \gamma}})/\Gamma_{\text{total}}{\times }$ $\Gamma($ ${{\mathit B}^{+}}$ $\rightarrow$ ${{\mathit \eta}_{{{c}}}}{{\mathit K}^{+}})/\Gamma_{\text{total}}$
$\Gamma_{59}/\Gamma{\times }\Gamma^{{{\mathit B}^{\pm}}}_{254}/\Gamma^{{{\mathit B}^{\pm}}}$