1. Final results on atmospheric  oscillations with MACRO at Gran Sasso Bari, Bologna, Boston, Caltech, Drexel, Frascati, Gran Sasso, Indiana, L’Aquila, Lecce, Michigan, Napoli, Pisa, Roma1, Texas, Torino, Oujda Gran Sasso Lab. – MACRO oscillations. Atmospheric neutrinos Upthroughoing muons (E  50 GeV ) – Zenith distribution – Absolute value – L/E distribution: E from  M.C.S. Monte Carlos Semicontained muons Upstopping muons Combining all information Conclusions E  4 GeV G. Giacomelli University of Bologna EPS, Aachen Ratio Absolute value

2. - Oscillations Weak flavour eigenstates e, ,  Mass eigenstates 1, 2, 3 Decays, Interactions  +   + ,  n   - p Propagation 1 (t) = 1 (0) e -E t Mixing 1 =  3 m = 1 U lm m 2-Flavour  = 2 cos  23 + 3 sin  23 Mixing  = - 2 cos  23 + 3 sin  23 Oscillations in Vacuum (over a distance L) Disappearance P(    ) = 1 – sin 2 2  23 sin 2 (1.27  m 2 23 L/E ) Appareance P(    ) = 1 – P(    )  m 2 23 = m 2 3 – m 2 2 Simple formulae -Additional flavour oscillations Modified by -Matter effects In case of -Neutrinos have masses m ≠ 0 Oscillations -L e, L, L , L violation -neutrino decays

3. E :  0.1 GeV   100 GeV L :  20 km   13000 km L/ E :  1 km/GeV   10 5 km/GeV Downgoing  : “near” neutrino source Upgoing  : “far” neutrino source Atmospheric neutrinos

4. The MACRO detector 3 types of Scintillators (  600 t) SubdetectorsStreamer tubes Nuclear track detectors Acceptance in  :10 -4    1 S   10,000 m 2 sr for isotropic flux 12 m horizontal Dimensions:76.6 m in length 9.3 m height Subdivided in 6 supermodules, with a lower and an upper part NIM A324(1993)337 NIM A486(2002)663

5. MACRO cross section (schematic)

6. Upthroughgoing muons MC SIMULATION (17% scale error): Bartol Group flux  Phys. Rev. D53 (1996) 1314 inter. Cross sections:  Z. Phys. C67 (1995) 433  Transport in the rock  CERN-EP / 85-03 (1985) Detector simulation: GEANT3 Shape of zenith distribution + L/E distribution  m 2 = 2.5  10 -3 eV 2, sin 2 2  = 1 Significance ~ 4.7  PL B357(1995)481 PL b434(1998)451 hep-ex/0206027

7. Monte Carlos New FLUKA and HKKM: complete three dimensional MCs with improved hadronic model Predictions of FLUKA and HKKM agree perfectly Shapes of zenith distributions with and without oscillations are the same in old Bartol flux, new FLUKA and new HKKM Using the latest primary Cosmic Ray fits: Absolute values are ~ 20-30% lower than MACRO and SUPER K data Using previous Cosmic Ray fits: Absolute values are 5-10% lower than MACRO, SUPER K Need to improve these fits

8. L/E Distribution ● Black points : upthroughgoing  data ○ Open point : Internal Up (IU)  data Green and red lines: MC predictions for    oscillations with the mentioned parameters point-to-point syst. error (12%) Shaded region: NIM A492(2002)376 hep-ex/0304037

9. Zenith distributions for IU  and (ID+UGS)  Shaded regions: no oscillation MC (21% scale error) Black lines: MC predictions for    oscillations with  m 2 = 2.5  10 -3 eV 2 and sin 2 2  = 1 Data are in agreement with MC OSC with the quoted parameters 262 events 164 events  4 GeV PL B478(2000)5 hep-ex/0206027

10. Combination of indipendent data Zenith distrib. Energy measur. H.E. 50 GeV L.E. 4 GeV AbsoluteH.E.Scale error  17% ValuesL.E.Scale error  21% MACRO data are consistent with    oscillations, with Maximal mixing  m 2 = 0.0023 eV 2 (  5  significance) Conclusions