${{\mathit \Upsilon}{(1S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \eta}_{{{c}}}{(1S)}}$  Decay Mode Summary INSPIRE   PDGID:
M049.119
Mode (*) Fraction ($\Gamma_i$ / $\Gamma$) Scale Factor/
Conf. Level		 P(MeV/c)  
$\Gamma_{110}$ ${{\mathit \Upsilon}{(1S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \eta}_{{{c}}}{(1S)}}$ $<2.9 \times 10^{-5}$ CL= 90% 4260
Category: Radiative decays
The following data is related to the above value:
$\Gamma($ ${{\mathit \Upsilon}{(1S)}}$ $\rightarrow$ ${{\mathit \gamma}}{{\mathit \eta}_{{{c}}}{(1S)}})/\Gamma_{\text{total}}$
$\Gamma_{110}/\Gamma$