Search for the lepton flavour violating decay $\mu ^+ \rightarrow \mathrm {e}^+ \gamma $ with the full dataset of the MEG experiment: MEG Collaboration

• Published in: The European physical journal. C, Particles and fields Vol. 76; no. 8
• Main Authors: Baldini, A. M., Bao, Y., Baracchini, E., Bemporad, C., Berg, F., Biasotti, M., Boca, G., Cascella, M., Cattaneo, P. W., Cavoto, G., Cei, F., Cerri, C., Chiarello, G., Chiri, C., Corvaglia, A., de Bari, A., De Gerone, M., Doke, T., D’Onofrio, A., Dussoni, S., Egger, J., Fujii, Y., Galli, L., Gatti, F., Grancagnolo, F., Grassi, M., Graziosi, A., Grigoriev, D. N., Haruyama, T., Hildebrandt, M., Hodge, Z., Ieki, K., Ignatov, F., Iwamoto, T., Kaneko, D., Kang, T. I., Kettle, P. -R., Khazin, B. I., Khomutov, N., Korenchenko, A., Kravchuk, N., Lim, G. M. A., Maki, A., Mihara, S., Molzon, W., Mori, Toshinori, Morsani, F., Mtchedilishvili, A., Mzavia, D., Nakaura, S., Nardò, R., Nicolò, D., Nishiguchi, H., Nishimura, M., Ogawa, S., Ootani, W., Orito, S., Panareo, M., Papa, A., Pazzi, R., Pepino, A., Piredda, G., Pizzigoni, G., Popov, A., Raffaelli, F., Renga, F., Ripiccini, E., Ritt, S., Rossella, M., Rutar, G., Sawada, R., Sergiampietri, F., Signorelli, G., Simonetta, M., Tassielli, G. F., Tenchini, F., Uchiyama, Y., Venturini, M., Voena, C., Yamamoto, A., Yoshida, K., You, Z., Yudin, Yu. V., Zanello, D.
• Format: Journal Article
• Language: English
• Published: United States Springer 03-08-2016
• Subjects: PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
• ISSN: 1434-6044; 1434-6052

Our 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. Furthermore, there was not a significant excess of events 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.