More Results from the Opera Experiment at the Gran Sasso Underground Lab

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2017-09-05
Kamışcıoğlu, Mustafa
The OPERA experiment reached its main goal by proving the appearance of nu(tau) in the CNGS nu(mu) beam. Five nu(tau) candidates fulfilling the analysis defined in the proposal were detected with a S/B ratio of about ten allowing to reject the null hypothesis at 5.1 sigma. The search has been extended by loosening the selection criteria in order to obtain a statistically enhanced, lower purity, signal sample. One such interesting neutrino interaction with a double vertex topology having a high probability of being a nu(tau) interaction with charm production is reported. Based on the enlarged data sample the estimation of Delta m(23)(2) in appearance mode is presented. The search for nu(e) interactions has been extended over the full data set with a more than twofold increase in statistics with respect to published data. The analysis of the nu(mu) -> nu(e) channel is updated and the implications of the electron neutrino sample in the framework of the 3+1 neutrino model is discussed. An analysis of nu(mu) -> nu(tau) interactions in the framework of the sterile neutrino model has also been performed. Finally, the results of the study of charged hadron multiplicity distributions is presented.

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Citation Formats
M. Kamışcıoğlu, “More Results from the Opera Experiment at the Gran Sasso Underground Lab,” 2017, vol. 46, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/56566.