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.
journal contribution
posted on 2023-06-07, 19:18authored byP Astier, D Autiero, A Baldisseri, M Baldo-ceolin, M Banner, G Bassompierre, K Benslama, N Besson, I Bird, B Blumenfield, F Bobisut, J Bouchez, S Boyd, A Bueno, S Bunyavot, L Camilleri, A Cardini, PW Cattaneo, V Cavasinni, A Cervera-Villanueva, A Chukanov, G Collazoul, G Conforto, C Conta, M Contalbrigo, R Cousini, D Daniles, H Degaudenzi, T Del Prete, A De Santo, T Dignan, L Di Lella, E do Cuoto e Silva, J Dumarchez, M Ellis, GJ Fieldman, R Ferrari, D Ferrere, V Flaminio, M Fraternali, JM Gaillard, E Gangler, A Geiser, D Greppert, D Gibin, S Gninenko, A Godley, JJ Gomez-Cadenas, J Gosset, C Gößling, M Gouanere, A Grant, G Graziani, A Guglielm, C Hagner, J Hernando, D Hubbard, P Hurst, N Hyett, E Lacopini, C Joseph, F Juget, M Kirsanov, O Klimov, J Kokkonen, A Kovzelev, A Krasnoperov, D Kustov, VE Kuznetsov, S Lacrapana, C Lachaud, B Lakic, A Lanza, L La Rotonda, M Laveder, A Letessier-selvon, JM Levy, L Linssen, A Ljubic, J Long, A Lupi, A Marchionni, F Martelli, X Mechain, JP Mendiburu, JP Meyer, M Mezzetto, SR Mishra, GF Moorhead, D Naumov, P Nedelec, Yu Nefedovf, C Nguyen-Mau, D Orestano, F Pastore, L.S Peak, E Pennacchio, H Pessard, R Petti, A Placci, G Polesello, D Pollmann, A Polyarush, B Popov, C Poulsen, J Rico, P Riemann, C Roda, A Rubbia, Fabrizio SalvatoreFabrizio Salvatore, K Schahmaneche, B Schmidt, T Schmidt, A Sconza, M Sevoir, D Sillou, FJP Soler, G Sozzi, D Steele, U Stiegler, M Stipcw, T Stolarczyk, M Tareb-Reyes, GN Tylor, V Tereshchenko, A Toropin, A-M Touchard, SN Tovey, M.T Tran, E Tsesmelis, J Ulrichs, L Vacavant, M Valdata-Nappi, V Valuev, F Vannucci, KE Varvell, M Veltri, V Vercesi, G Vidal-Sitjes, JM Vieira, T Vinogradova, FV Weber, T Weisse, FF Wilson, LJ Winton, BD Yabsley, H Zaccone, Kai Zuber, P Zuccon
Results from the ?t appearance search in a neutrino beam using the full NOMAD data sample are reported. A new analysis unifies all the hadronic t 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 sin22?µt–?m2 plane which includes sin22?µt<3.3×10-4 at large ?m2 and ?m2< 0.7 eV2/c4 at sin22?µt=1. The corresponding contour in the ?e??t oscillation hypothesis results in sin22?et<1.5×10-2 at large ?m2 and ?m2<5.9 eV2/c4 at sin22?et=1. We also derive limits on effective couplings of the t lepton to ?µ or ?e.
This is the final result of the NOMAD oscillation analysis. I was involved in the hardware (expert) to guarantee the data quality and in reconstruction of muon tracks in NOMAD. This is the most crucial input to determine the neutrino spectrum which resulted in the world's most sensitive oscillation search.