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Search for a new gauge boson in $\pi^{0}$ decays (1998) |
- Altegoer, J,
- Astier, Pierre,
- Autiero, D,
- Baldisseri, Alberto,
- Baldo-Ceolin, Massimilla,
- Ballocchi, G,
- Banner, M,
- Basa, S,
- Bassompierre, Gabriel,
- Benslama, K,
- Besson, N,
- Bird, I G,
- Blumenfeld, B,
- Bobisut, F,
- Bouchez, J,
- Boyd, S,
- Bueno, A G,
- Bunyatov, S A,
- Camilleri, L L,
- Cardini, A,
- Castera, A,
- Cattaneo, Paolo Walter,
- Cavasinni, V,
- Cervera-Villanueva, A,
- Collazuol, G,
- Conforto, G,
- Conta, C,
- Contalbrigo, M,
- Cousins, R D,
- Daniels, D C,
- De Santo, A,
- Del Prete, T,
- Dignan, T,
- Di Lella, L,
- Donnelly, I J,
- Dumarchez, J,
- Fazio, T,
- Feldman, G J,
- Ferrari, R,
- Ferrère, D,
- Flaminio, Vincenzo,
- Fraternali, M,
- Gaillard, Jean-Marc,
- Galumian, P I,
- Gangler, E,
- Geiser, A,
- Geppert, D,
- Gibin, D,
- Gninenko, S N,
- Gómez-Cadenas, J J,
- Gosset, J,
- Gössling, C,
- Gouanère, M,
- Grant, A,
- Graziani, G,
- Guglielmi, A M,
- Hagner, C,
- Hernando, J,
- Hubbard, D B,
- Hurst, P,
- Hyett, N,
- Iacopini, E,
- Joseph, C L,
- Kekez, D,
- Kirsanov, M M,
- Klimov, O L,
- Kokkonen, J,
- Kovzelev, A,
- Kuznetsov, V E,
- Lacaprara, S,
- Lanza, A,
- La Rotonda, L,
- Laveder, M,
- Letessier-Selvon, A A,
- Lévy, J M,
- Linssen, Lucie,
- Ljubicic, A,
- Long, J,
- Lupi, A,
- Manola-Poggioli, E,
- Marchionni, A,
- Martelli, F,
- Méchain, X,
- Mendiburu, J P,
- Meyer, J P,
- Mezzetto, Mauro,
- Mishra, S R,
- Moorhead, G F,
- Mossuz, L,
- Nédélec, P,
- Nefedov, Yu A,
- Nguyen-Mau, C,
- Orestano, D,
- Pastore, F,
- Peak, L S,
- Pennacchio, E,
- Perroud, Jean-Pierre,
- Pessard, H,
- Petti, R,
- Placci, Alfredo,
- Plothow-Besch, Hartmute,
- Pluquet, A,
- Polesello, G,
- Pollmann, D,
- Pope, B G,
- Popov, B A,
- Poulsen, C,
- Rathouit, P,
- Roda, C,
- Rubbia, André,
- Salvatore, F,
- Scannicchio, D A,
- Schahmaneche, K,
- Schmidt, B,
- Sconza, A,
- Serrano, M,
- Sevior, M E,
- Sillou, D,
- Soler, F J P,
- Sozzi, G,
- Steele, D,
- Steffen, P,
- Steininger, M,
- Stiegler, U,
- Stipcevic, M,
- Stolarczyk, T,
- Tareb-Reyes, M,
- Taylor, G N,
- Tereshchenko, S,
- Toropin, A N,
- Touchard, A M,
- Tovey, Stuart N,
- Tran, M T,
- Tsesmelis, E,
- Ulrichs, J,
- Urós, V,
- Valdata-Nappi, M,
- Valuev, V Yu,
- Vannucci, François,
- Varvell, K E,
- Veltri, M,
- Vercesi, V,
- Verkindt, D,
- Vieira, J M,
- Vinogradova, T G,
- Vo, M K,
- Volkov, S,
- Weber, F,
- Weisse, T,
- Werlen, M,
- Wilson, F F,
- Winton, L J,
- Yabsley, B D,
- Zaccone, Henri,
- Zuber, K
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Abstract |
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A search was made for a new light gauge boson $X$ which might be produced in $\pi^{0}\rightarrow\gamma + X$ decay from neutral pions generated by 450-GeV protons in the CERN SPS neutrino target. Th e X's would penetrate the downstream shielding and be observed in the NOMAD detector via the Primakoff effect, in the process of $X \rightarrow\pi^{0}$ conversion in the external Coulomb field of a nucleus.\ With $1.45\times10^{18}$ protons on target, 20 candidate events with energy between 8 and 140 GeV were found from the analysis of neutrino data.\ This number is in agreement with the e xpectation of 18.1$\pm$2.8 background events from standard neutrino processes.\ A new 90 $\% ~C.L.$ upper limit on the branching ratio $Br(\pi^{0}\rightarrow\gamma + X) |
Publication details |
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