More results from the OPERA experiment


Galati G., Agafonova N., Aleksandrov A., Anokhina A., Aoki S., Ariga A., ...Daha Fazla

NUOVO CIMENTO C-COLLOQUIA AND COMMUNICATIONS IN PHYSICS, cilt.40, sa.5, 2017 (ESCI) identifier identifier

Özet

The OPERA experiment reached its main goal by proving the appearance of nu(tau) in the CNGS nu(mu) beam. Five nu(tau) candidates were detected with a S/B ratio of similar to 10, allowing to reject the null hypothesis at 5.1 sigma. The search has been extended by loosening the selection criteria in order to improve the statistical uncertainty. One of the nu(tau) candidates selected with the new strategy shows a double vertex topology and, after a dedicated multivariate analysis, is compatible with being a nu(tau) interaction with charm production. Based on the enlarged data sample the estimation of Delta m(23)(2) in appearance mode is being performed. The search for nu(e) 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 sin(2) 2 theta(mu e). Finally, the analysis of the annual modulation of cosmic muons is introduced.