Evidence for the decay $X(3872)rightarrowpsi(2S)gamma$

Evidence for the decay mode $X(3872)rightarrowpsi(2S)gamma$ in $B^+rightarrow X(3872)K^+$ decays is found with a significance of 4.4 standard deviations. The analysis is based on a data sample of proton-proton collisions, corresponding to an integrated luminosity of 3fb$^{-1}$ collected with the LHCb detector, at centre-of-mass energies of 7 and 8TeV. The ratio of the branching fraction of the $X(3872)topsi(2S)gamma$ decay to that of the $X(3872)rightarrow J/psi gamma$ decay is measured to be $$ frac{Br(X(3872)rightarrowpsi(2S)gamma)}{Br(X(3872)rightarrow J/psigamma)} = 2.46pm0.64pm0.29, %pm0.06,$$ where the first uncertainty is statistical and the second is systematic. The measured value agrees with expectations for a pure charmonium interpretation of the $X(3872)$ state and a mixture of charmonium and molecular interpretations. However, it does not support a pure $Dbar{D}^{*}$ molecular interpretation of the $X(3872)$state.