https://doi.org/10.1051/epjconf/20122812031
Measurement of the ratio of branching fractions 
1
Institute of Theoretical and Experimental Physics (ITEP, Moscow )
2
Lomonosov Moscow State University (SINP MSU)
a e-mail: Daria.Savrina@cern.ch
The interest to the rare radiative decays of the B-mesons at LHCb is mostly aroused due to the measurement of the photon polarization in the Bs0 → ϕγ decay, which may provide a sensitive probe for the Standard Model. The LHCb experiment has started to take data at the energy of √s = 7 TeV in 2010 and the current paper presents the result of the studies of the two rare radiative decays B0 → K*γ and Bs0 → ϕγ with 340 pb−1 of data taken in the first half of 2011. With this data we have a preliminary measurement of = 1.52±0.14(stat.)±0.10(syst.)±0.12(fs/fd) and assuming the measured value of 
(B0 → K*γ) = (4.33 ± 0.15) × 10.5 we infer
(Bs0 → ϕγ) = (2.8 ± 0.5) × 10−5 [1]
© Owned by the authors, published by EDP Sciences, 2012
