FINAL NOMAD RESULTS ON MUON-NEUTRINO ---> TAU-NEUTRINO AND ELECTRON-NEUTRINO ---> TAU-NEUTRINO OSCILLATIONS INCLUDING A NEW SEARCH FOR TAU-NEUTRINO APPEARANCE USING HADRONIC TAU DECAYS

Astier, P.; Autiero, D.; Baldisseri, A.; Baldo, Massimilla; Banner, M.; Bassompierre, G.; Benslama, K.; Besson, N.; Bird, I.; Blumenfeld, B.; Bobisut, Furio; Bouchez, J.; Boyd, S.; Bueno, A.; Bunyatov, S.; Camilleri, L.; Cardini, A.; Cattaneo, P. W.; Cavasinni, V.; CERVERA VILLANUEVA, A.; Chukanov, A.; Collazuol, Gianmaria; Conforto, G.; Conta, C.; Contalbrigo, M.; Cousins, R.; Daniels, D.; Degaudenzi, H.; DEL PRETE, T.; DE SANTO, A.; Dignan, T.; DI LELLA, L.; Silva, E. DO COUTO E.; Dumarchez, J.; Ellis, M.; Feldman, G. J.; Ferrari, R.; Ferrere, D.; Flaminio, V.; Fraternali, M.; Gaillard, J. M.; Gangler, E.; Geiser, A.; Geppert, D.; Gibin, Daniele; Gninenko, S.; Godley, A.; GOMEZ CADENAS, J. J.; Gosset, J.; Gossling, C.; Gouanere, M.; Grant, A.; Graziani, G.; Guglielmi, A.; Hagner, C.; Hernando, J.; Hubbard, D.; Hurst, P.; Hyett, N.; Iacopini, E.; Joseph, C.; Juget, F.; Kirsanov, M.; Klimov, O.; Kokkonen, J.; Kovzelev, A.; Krasnoperov, A.; Kustov, D.; Kuznetsov, V. E.; Lacaprara, S.; Lachaud, C.; Lakic, B.; Lanza, A.; LA ROTONDA, L.; Laveder, Marco; LETESSIER SELVON, A.; Levy, J. M.; Linssen, L.; Ljubicic, A.; Long, J.; Lupi, A.; Marchionni, A.; Martelli, F.; Mechain, X.; Mendiburu, J. P.; Meyer, J. P.; Mezzetto, M.; Mishra, S. R.; Moorhead, G. F.; Naumov, D.; Nedelec, P.; Nefedov, Y. U.; NGUYEN MAU, C.; Orestano, D.; Pastore, F.; Peak, L. S.; Pennacchio, E.; Pessard, H.; Petti, R.; Placci, A.; Polesello, G.; Pollmann, D.; Polyarush, A.; Popov, B.; Poulsen, C.; Rico, J.; Riemann, P.; Roda, C.; Rubbia, A.; Salvatore, F.; Schahmaneche, K.; Schmidt, B.; Schmidt, T.; Sconza, Andrea; Sevior, M.; Sillou, D.; Soler, F. J. P.; Sozzi, G.; Steele, D.; Stiegler, U.; Stipcevic, M.; Stolarczyk, T.; TAREB REYES, M.; Taylor, G. N.; Tereshchenko, V.; Toropin, A.; Touchard, A. M.; Tovey, S. N.; Tran, M. T.; Tsesmelis, E.; Ulrichs, J.; Vacavant, L.; VALDATA NAPPI, M.; Valuev, V.; Vannucci, F.; Varvell, K. E.; Veltri, M.; Vercesi, V.; VIDAL SITJES, G.; Vieira, J. M.; Vinogradova, T.; Weber, F. V.; Weisse, T.; Wilson, F. F.; Winton, L. J.; Yabsley, B. D.; Zaccone, H.; Zuber, K.; Zuccon, P.

doi:10.1016/S0550-3213(01)00339-X

Results from the v, appearance search in a neutrino beam using the full NOMAD data sample are reported. A new analysis unifies all the hadronic tau decays, significantly improving the overall sensitivity of the experiment to oscillations. The "blind analysis" of all topologies yields no evidence for an oscillation signal. In the two-family oscillation scenario, this sets a 90% CL allowed region in the sin(2)2 theta (mu tau)-Deltam(2) plane which includes sin(2)2 theta (mu tau) < 3.3 x 10(-4) at large Deltam(2) and Deltam(2) < 0.7 eV(2)/c(4) at sin(2) 2 theta (mu tau) = 1. The corresponding contour in the nu (e) --> nu (tau) oscillation hypothesis results in sin(2) 2 theta (l tau) < 1.5 x 10(-2) at large Deltam(2) and Deltam(2) < 5.9 eV(2)/c(4) at sin(2) 2 theta (l tau) = 1. We also derive limits on effective couplings of the tau lepton to nu (mu) or nu (l).