Observation of J/psi-->3gamma.

/ Authors

G. Adams, M. Anderson, J. Cummings, I. Dankó, D. Hu, B. Moziak, J. Napolitano, Q. He, J. Insler, H. Muramatsu

and 99 more authors

C. S. Park, E. Thorndike, F. Yang, M. Artuso, S. Blusk, S. Khalil, J. Li, R. Mountain, S. Nisar, K. Randrianarivony, N. Sultana, T. Skwarnicki, S. Stone, J. Wang, L. Zhang, G. Bonvicini, D. Cinabro, M. Dubrovin, A. Lincoln, P. Naik, J. Rademacker, D. Asner, K. Edwards, J. Reed, R. Briere, T. Ferguson, J. Ma, G. Tatishvili, H. Vogel, M. E. Watkins, J. Rosner, J. Alexander, D. Cassel, J. Duboscq, R. Ehrlich, L. Fields, R. Galik, L. Gibbons, R. Gray, S. Gray, D. Hartill, B. Heltsley, D. Hertz, J. Hunt, J. Kandaswamy, D. Kreinick, V. Kuznetsov, J. Ledoux, H. Mahlke-Krüger, D. Mohapatra, P. Onyisi, J. Patterson, D. Peterson, D. Riley, A. Ryd, A. Sadoff, X. Shi, S. Stroiney, W. Sun, T. Wilksen, S. Athar, R. Patel, J. Yelton, P. Rubin, B. Eisenstein, I. Karliner, S. Mehrabyan, N. Lowrey, M. Selen, E. White, J. Wiss, R. Mitchell, M. Shepherd, D. Besson, T. Pedlar, D. Cronin-Hennessy, K. Gao, J. Hietala, Y. Kubota, T. Klein, B. Lang, R. Poling, A. Scott, P. Zweber, S. Dobbs, Z. Metreveli, K. Seth, A. Tomaradze, J. Libby, A. Powell, G. Wilkinson, K. Ecklund, W. Love, V. Savinov, H. Mendez, J. Ge, D. Miller, I. Shipsey, B. Xin

/ Abstract

We report the first observation of the decay J/psi-->3gamma. The signal has a statistical significance of 6sigma and corresponds to a branching fraction of B(J/psi-->3gamma)=(1.2+/-0.3+/-0.2)x10;{-5}, in which the errors are statistical and systematic, respectively. The measurement uses psi(2S)-->pi;{+}pi;{-}J/psi events acquired with the CLEO-c detector operating at the CESR e;{+}e;{-} collider.

Journal: Physical review letters

DOI: 10.1103/PhysRevLett.101.101801