1. Congresso del Dipartimento di Fisica Highlights in Physics 2005 11–14 October 2005, Dipartimento di Fisica, Università di Milano Icarus: a multipurpose detector; the simulation codes G. Battistoni *, A. Ferrari *†, S. Muraro * and P.R. Sala * * INFN sezione di Milano † on leave at CERN The ICARUS experiment has a vast physics program, including proton decay, and neutrino oscillations from natural and artificial sources. The so-called T600 detector, composed by two modules, 300 tons of Liquid Argon each, is now in the Gran Sasso Hall B and will be operational next year Drifting Ionizing Track e-e- light Ionization in LiquidArgon Drift in E field Induced/collected signals on wire grids 2-dim views: wire vs. drift time 3-d reconstruction with 3 wire planes K+ µ+ e+ Run 939 Event 46 K+K+ ++ e+e+ p  K + e _ p=425 MeV CERN Neutrino to Gran Sasso: ν beam from 400GeV proton beam, 732 km path to Gran Sasso Laboratory. Main aim is the direct detection of τ neutrinos from ν μ → ν τ oscillation FLUKA simulation includes all details of beam transport, interaction, structure of target, horn focusing, decay, etc. Used for engineering calculations and for the prediction of ν fluxes at Gran Sasso 20 m 3 m The detection Principle : LAr Time Projection Chamber: An electronic bubble chamber with 3mm resolution + calorimetry Hadronic Interaction. Real event in 2001 test Proton decay : a test of baryon Number conservation. Important for GUT theories and matter-antimatter asymmetry FLUKA is an interaction and transport MonteCarlo code, used for many applications from high energy physics to microdosimetry. It is an INFN-CERN project. Special developments/applications for ICARUS from INFN-Milano and CERN FLUKA simulated proton decay event In T600 CNGS beam line FLUKA simulated ν μ flux Three flavor oscillations with matter effect, for ν μ → ν e studies in view of the determination of the theta13 parameter have been recently coupled to CNGS and atmospheric analysis The plot shows the expected ν e and ν τ spectra for the CNGS beam, with and without 3-F oscillation To identify p decay in an Ar nucleus, It is essential to understand and reproduce nuclear effects, such as Fermi motion, binding energy, reinteraction of decay products inside the nucleus: Handled by the FLUKA nuclear model Real event with K decay Oscillation of atmospheric ν has been detected in the SuperKamiokande experiment. However, a better understanding of theoretical flux and experimental systematics would be welcome Fluka simulations of cosmic showers in atmosphere, including geomagnetic effects have been set up and checked: here muon spectrum at ground level, simulated (line) and expt (dots) Result: first full 3-D simulation of atm. ν Coupled to simulation of ν interactions, with nuclear effects, and full ICARUS simulation of tracks in the detector References S. Amerio et al. (ICARUS coll.) NIM A 527, 329 (2004) P. Aprili et al (ICARUS coll.) LNGS-P28/2001 and CERN-SPSC-2002-027 A. Fasso et al. FLUKA, CERN yellow report, INFN/TC_05/11, in press; A. Fasso et al., arXiv:hep-ph/0306267; www.fluka.orgwww.fluka.org G. Acquistapace et al., NGS, CERN-98-02 (1998); R. Baldy et al., INFN/AE-99/05 and CERN SL- 99-034 DI (1999) A. Ferrari et al., Nucl. Phys. B - Proc.Suppl. 145,93 (2005) G. Battistoni et al., Astropart. Phys 12, 315 (2000); Astropart. Phys. 19,269 (2004); Astropart. Phys. 17, 477 (2002) ICARUS upgraded analysis, ICARUS TM/05-04