OPERA (Oscillation Project with Emulsion tRacking Apparatus) was a long-baseline experiment at the INFN Gran Sasso laboratory (LNGS) designed to search for νμ → ντ oscillations in appearance mode. It took data from 2008 to 2012 with the CNGS neutrino beam from CERN. In 2015, after the detection of five ντ candidates with a signal-to-background ratio of ∼ 10, the discovery of ντ appearance in the CNGS beam was announced with 5.1σ significance. After having reached the experiment main goal, the selection of ντ candidates has been extended by loosening the selection criteria and applying a multivariate approach for events identification, in order to improve the statistical uncertainty in the measurement of the oscillation parameters and of ντ properties. Future experiments that will take advantage of the improvements done by OPERA in the use of nuclear emulsions will also be described.
Final results of the OPERA experiment on ντ appearance and the OPERA legacy
Galati G.
Writing – Original Draft Preparation
2019-01-01
Abstract
OPERA (Oscillation Project with Emulsion tRacking Apparatus) was a long-baseline experiment at the INFN Gran Sasso laboratory (LNGS) designed to search for νμ → ντ oscillations in appearance mode. It took data from 2008 to 2012 with the CNGS neutrino beam from CERN. In 2015, after the detection of five ντ candidates with a signal-to-background ratio of ∼ 10, the discovery of ντ appearance in the CNGS beam was announced with 5.1σ significance. After having reached the experiment main goal, the selection of ντ candidates has been extended by loosening the selection criteria and applying a multivariate approach for events identification, in order to improve the statistical uncertainty in the measurement of the oscillation parameters and of ντ properties. Future experiments that will take advantage of the improvements done by OPERA in the use of nuclear emulsions will also be described.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.