New limit on the lepton-flavor-violating decay μ+→e +γ

J. Adam, X. Bai, A. M. Baldini, E. Baracchini, C. Bemporad, G. Boca, P. W. Cattaneo, G. Cavoto, F. Cei, C. Cerri, A. De Bari, M. De Gerone, T. Doke, S. Dussoni, J. Egger, K. Fratini, Y. Fujii, L. Galli, G. Gallucci, F. GattiB. Golden, M. Grassi, D. N. Grigoriev, T. Haruyama, M. Hildebrandt, Y. Hisamatsu, F. Ignatov, T. Iwamoto, P. R. Kettle, B. I. Khazin, O. Kiselev, A. Korenchenko, N. Kravchuk, A. Maki, S. Mihara, W. Molzon, T. Mori, D. Mzavia, H. Natori, D. Nicolò, H. Nishiguchi, Y. Nishimura, W. Ootani, M. Panareo, A. Papa, R. Pazzi, G. Piredda, A. Popov, F. Renga, S. Ritt, M. Rossella, R. Sawada, F. Sergiampietri, G. Signorelli, S. Suzuki, F. Tenchini, C. Topchyan, Y. Uchiyama, R. Valle, C. Voena, F. Xiao, S. Yamada, A. Yamamoto, S. Yamashita, Yu V. Yudin, D. Zanello

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214 Citations (Scopus)


We present a new result based on an analysis of the data collected by the MEG detector at the Paul Scherrer Institut in 2009 and 2010, in search of the lepton-flavor-violating decay μ+→e+γ. The likelihood analysis of the combined data sample, which corresponds to a total of 1.8×1014 muon decays, gives a 90% C.L. upper limit of 2.4×10 -12 on the branching ratio of the μ+→e +γ decay, constituting the most stringent limit on the existence of this decay to date.

Original languageEnglish
Article number171801
JournalPhysical review letters
Issue number17
Publication statusPublished - 2011 Oct 17
Externally publishedYes


ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Adam, J., Bai, X., Baldini, A. M., Baracchini, E., Bemporad, C., Boca, G., Cattaneo, P. W., Cavoto, G., Cei, F., Cerri, C., De Bari, A., De Gerone, M., Doke, T., Dussoni, S., Egger, J., Fratini, K., Fujii, Y., Galli, L., Gallucci, G., ... Zanello, D. (2011). New limit on the lepton-flavor-violating decay μ+→e +γ. Physical review letters, 107(17), [171801].