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Precise measurement of the decay $K_{L} \to \pi^{0}\gamma\gamma$

The decay rate of $K_{L} \to \pi^{0}\gamma\gamma$ has been measured with the NA48 detector at the CERN SPS. A total of 2558 $K_{L} \to \pi^{0}\gamma\gamma$ candidates have been observed with a residual background of 3.2%. The branching ratio is determined to be $(1.36 \pm 0.03_{(stat)} \pm 0.03_{(sy...

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Detalles Bibliográficos
Autores principales: Lai, A., Marras, D., Bevan, A., Dosanjh, R.S., Gershon, T.J., Hay, B., Kalmus, G.E., Lazzeroni, C., Munday, D.J., Needham, M.D., Olaiya, E., Parker, Michael Andrew, White, T.O., Wotton, S.A., Barr, G., Bocquet, G., Ceccucci, A., Cuhadar-Donszelmann, T., Cundy, D., D'Agostini, G., Doble, N., Falaleev, V., Gatignon, L., Gonidec, A., Gorini, B., Govi, G., Grafstrom, P., Kubischta, W., Lacourt, A., Lenti, M., Luitz, S., Mikulec, I., Norton, A., Palestini, S., Panzer-Steindel, B., Tatishvili, G., Taureg, H., Velasco, M., Wahl, Heinrich, Cheshkov, C., Hristov, P., Kekelidze, V., Madigojine, D., Molokanova, N., Potrebenikov, Yu., Zinchenko, A., Knowles, I., Martin, V., Sacco, R., Walker, A., Contalbrigo, M., Dalpiaz, P., Duclos, J., Frabetti, P.L., Gianoli, A., Martini, M., Petrucci, F., Savrie, M., Bizzeti, A., Calvetti, M., Collazuol, G., Graziani, G., Iacopini, E., Veltri, M., Becker, H.G., Eppard, M., Fox, H., Holtz, K., Kalter, A., Kleinknecht, K., Koch, U., Kopke, L., Lopes da Silva, P., Maruelli, P., Pellmann, I., Peters, A., Renk, B., Schmidt, S.A., Schonharting, V., Schue, Y., Wanke, R., Winhart, A., Wittgen, M., Chollet, J.C., Fayard, L., Iconomidou-Fayard, L., Ocariz, J., Unal, G., Wingerter-Seez, I., Anzivino, G., Cenci, P., Imbergamo, E., Lubrano, P., Mestvirishvili, A., Nappi, A., Pepe, M., Piccini, M., Carosi, R., Casali, R., Cerri, C., Cirilli, M., Costantini, F., Fantechi, R., Giudici, S., Mannelli, I., Pierazzini, G., Sozzi, M., Cheze, J.B., Cogan, J., De Beer, M., Debu, P., Formica, A., Granier de Cassagnac, R., Mazzucato, E., Peyaud, B., Turlay, R., Vallage, B., Holder, M., Maier, A., Ziolkowski, M., Arcidiacono, R., Biino, C., Cartiglia, N., Clemencic, M., Marchetto, F., Menichetti, Ezio A., Pastrone, N., Nassalski, J., Rondio, E., Szleper, M., Wislicki, W., Wronka, S., Dibon, H., Fischer, G., Jeitler, M., Markytan, M., Neuhofer, G., Pernicka, M., Taurok, A., Widhalm, L.
Lenguaje:eng
Publicado: 2002
Materias:
Acceso en línea:https://dx.doi.org/10.1016/S0370-2693(02)01863-4
http://cds.cern.ch/record/549947
Descripción
Sumario:The decay rate of $K_{L} \to \pi^{0}\gamma\gamma$ has been measured with the NA48 detector at the CERN SPS. A total of 2558 $K_{L} \to \pi^{0}\gamma\gamma$ candidates have been observed with a residual background of 3.2%. The branching ratio is determined to be $(1.36 \pm 0.03_{(stat)} \pm 0.03_{(syst)} \pm 0.03_{(norm)}) \times10^{-6}$ and the vector coupling constant $a_v = -0.46 \pm0.03_{(stat)} \pm0.04_{(syst)}$. This result suggests that the CP-violation effects are dominating in the $K_{L} \to \pi^{0}e^{+}e^{-}$ decay. An upper limit for the $K_{L} \to \pi^{0}\gamma\gamma$ decay rate in the two photon mass region $m_{\gamma\gamma}<m_{\pi^0}$ is also given.