LHCb: Radiative Decays at LHCb

In this work we present a measurement of the ratio of the branching fraction of the radiative decays $B^{0}\rightarrow K^{*0}\gamma$ and $B^{0}_{s}\rightarrow \phi\gamma$ using 1.0 fb$^{-1}$ of data taken with the LHCb detector. The value obtained is \begin{equation} \frac{B\left(B^{0}\rightarrow K^{*0}\gamma\right)}{B\left(B^{0}_{s}\rightarrow \phi\gamma\right)}=1.23\pm0.06(stat.)\pm0.04(syst.)\pm0.10\left(f_s/f_d\right) \end{equation} Using the world average value $B\left(B^{0}\rightarrow K^{*0}\gamma\right)=\left(4.33\pm0.15\right)\times10^{-5}$ branching fraction is determined to be $B\left(B^{0}_{s}\rightarrow \phi\gamma\right)=3.5\pm0.4\times10^{-5}$. A measurement of the direct CP asymmetry of the decay $B^{0}\rightarrow K^{*0}\gamma$ is also presented. Both measurements are the most precise to date and are in agreement with the previous experimental results and theoretical expectations.