The OPERA experiment reached its main goal by proving the appearance of vτ in the CNGS vμ beam. Five vτ candidates were detected with a S/B ratio of ∼ 10, allowing to reject the null hypothesis at 5.1σ. The search has been extended by loosening the selection criteria in order to improve the statistical uncertainty. One of the vτ candidates selected with the new strategy shows a double vertex topology and, after a dedicated multivariate analysis, is compatible with being a vTτ interaction with charm production. Based on the enlarged data sample the estimation of Δm223 in appearance mode is being performed. The search for ve interactions has been extended over the full data set with a more than twofold increase in statistics: data are compatible with the non-oscillation hypothesis in the three-flavour mixing model. The implications of the electron neutrino sample in the framework of the 3+1 sterile mode will lead to exclusion limits on sin2 2θμe. Finally, the analysis of the annual modulation of cosmic muons is introduced.
More results from the OPERA experiment
Galati G.
Writing – Original Draft Preparation
;De Serio M.;Paparella L.;Pastore A.;Simone S.;
2017-01-01
Abstract
The OPERA experiment reached its main goal by proving the appearance of vτ in the CNGS vμ beam. Five vτ candidates were detected with a S/B ratio of ∼ 10, allowing to reject the null hypothesis at 5.1σ. The search has been extended by loosening the selection criteria in order to improve the statistical uncertainty. One of the vτ candidates selected with the new strategy shows a double vertex topology and, after a dedicated multivariate analysis, is compatible with being a vTτ interaction with charm production. Based on the enlarged data sample the estimation of Δm223 in appearance mode is being performed. The search for ve interactions has been extended over the full data set with a more than twofold increase in statistics: data are compatible with the non-oscillation hypothesis in the three-flavour mixing model. The implications of the electron neutrino sample in the framework of the 3+1 sterile mode will lead to exclusion limits on sin2 2θμe. Finally, the analysis of the annual modulation of cosmic muons is introduced.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.