The final results of the search for the lepton flavour violating decay μ+→e+γ based on the full dataset collected by the MEG experiment at the Paul Scherrer Institut in the period 2009–2013 and totalling 7.5×1014 stopped muons on target are presented. No significant excess of events is observed in the dataset with respect to the expected background and a new upper limit on the branching ratio of this decay of B(μ+→e+γ)<4.2×10−13 (90 % confidence level) is established, which represents the most stringent limit on the existence of this decay to date.
Reference: Baldini, A.M., Bao, Y., Baracchini, e. et al, Eur. Phys. J. C 76 (2016), 434
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