End of CNGS run


8th NBI2012 workshop at CERN


First tau-neutrino candidate detected

Project Overview Beam Performance CNGS↔LNGS Publications/Talks Events Links
Technical Page (EDMS) Civil Engineering Naming Conventions Download Pictures Planning Search
Project Organization:  Secondary Beam WG, Project Team, Technical WG, Commissioning WG
cg.gif (821 bytes)
The expected neutrino fluences and event rates at Gran Sasso are given in the technical note of November 2000. As this is of interest to the experiments, the results are displayed in two neutrino energy regions, up to 30 and up to 100 GeV. For the main beam component, one finds:
cg.gif (821 bytes)
cg.gif (821 bytes)
  nm energy region [GeV] 1-30 1-100  
  nm fluence [m-2 (pot)-1] 7.36 x 10-9 7.78 x 10-9  
  nm CC events [(pot) -1 (kton)-1] 5.05 x 10-17 5.85 x 10-17  
cg.gif (821 bytes)
cg.gif (821 bytes)
Note that the unit ''pot'' stands for 1 proton on the CNGS target. CC events are the charged current events in the detector, i.e. events where the neutrino produces a charged lepton. The cross sections used for these calculations and for the nt charged current events can be found here.
The results found for the unwanted neutrino species are (relative to the main nm component):
  ne / nm 0.8 %    
  anti-nm / nm 2.1 %    
  anti-ne / nm 0.07 %    
cg.gif (821 bytes)
The energy distribution of these neutrino beam fluences, as well as the radial distribution (beam-size) at Gran Sasso are shown on the following pages.
The expected number of nt charged current events at Gran Sasso has been estimated for the case of an ideal detector with 100% detection efficiency (for the estimated numbers as predicted by the experiments, see the corresponding web-pages). The number of ''detectable events'' is given here for the hypothesis of two-neutrino mixing with sin2(2q)=1 and various assumed mass differences, and for a nominal running year with 4.5 x 1019 protons on target:
  nt energy region [GeV] 1-30 1-100  
  Dm2 = 1 x 10-3 eV2 2.44 2.53  
  Dm2 = 3 x 10-3 eV2 21.6 22.5  
  Dm2 = 5 x 10-3 eV2 58.3 60.5  
  Dm2 = 1 x 10-2 eV2 204 212  
cg.gif (821 bytes)
grille5.gif (1109 bytes)