Author/Authors :
Barichello، نويسنده , , G. and Bergnoli، نويسنده , , A. and Brugnera، نويسنده , , R. and Candela، نويسنده , , A. and Carrara، نويسنده , , E. and DʹIncecco، نويسنده , , M. and Dal Corso، نويسنده , , F. and Degli Esposti، نويسنده , , L. and Dusini، نويسنده , , S. and Garfagnini، نويسنده , , A. and Gustavino، نويسنده , , C. and Lindozzi، نويسنده , , M. and Mengucci، نويسنده , , A. and Monacelli، نويسنده , , P. and Paoloni، نويسنده ,
Abstract :
OPERA is one of the two detectors foreseen in the CERN Neutrino to Gran Sasso project, devoted to the detection of ν μ into ν τ oscillations in the parameter region suggested by SuperKamiokande data on atmospheric neutrinos. Bakelite RPCs will be used to instrument the iron yoke of the muon spectrometers. We present the results of long-term (greater than 6 months) streamer operations of real size OPERA RPCs at cosmic rays fluxes. Given the very low rate observed in the underground Gran Sasso Laboratories, under 3 km w.e., even this short time period is equivalent to more than 10 OPERA years. Results of tests with different gas mixtures are reported, in view of decreasing the streamer charge of operation for the RPCs employed in the experiment.
