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14 Detectors at ( ) CHORUS NOMAD Roberto Petti Neutrino beam

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26 NETSCAN location (Phase II): Pick up all track segments (θ < 0.4 rad) in the scanning volume (1.5 x 1.5 mm 2 8 plates) Offline analysis of emulsion data At least 2-segment connected tracks Reconstruct full vertex topology Track segments from 8 plates overlapped Eliminate passingthrough tracks Roberto Petti

27 Automatic microscope at : Megapixel CCD and XYZ stage 71 cm High Performance optics 36 cm Roberto Petti

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35 MOTIVATIONS FOR CNGS n m disappearance in Super-K: SuperK n m - n t 1.2 < Dm 2 < 5.4 x 10-3 ev 2 at 90% CL % Best fit Dm 2 = 2.4 x 10-3 ev 2 n m disappearance in K2K: Expected (no osc.) Detected 56 (~ 2s effect) Oscillation dip in the E ν spectrum at m 2 ~ 3 x 10-3 ev 2? n t appearance in Super-K Poor S/B ratio ~ 0.7%, statistical significance ~ 2s Roberto Petti Sterile ν disfavoured at ~ 99% events K2K? n energy (GeV)

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38 CNGS status: civil engineering Roberto Petti

39 CNGS status: schedule today Roberto Petti

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41 THE OPERA DETECTOR n supermodule m spectrometer Magnetised Iron Dipoles Drift tubes and RPCs ~ 10 m brick (56 Pb/Em. cells ) module 8 cm (10X 0 ) n target and t decay detector Each supermodule is a sequence of 24 modules consisting of - a wall of Pb/emulsion bricks Roberto Petti - two planes of orthogonal scintillator strips brick wall scintillator strips 235,000 bricks

42 Status of the experiment Approved as CNGS1 in 2000 Construction & test of full-scale prototypes completed Target tracker module Wall support structure Starting final construction Roberto Petti Magnet during construction

43 THE DONUT BENCHMARK ν τ has been detected in the DONUT ECC t hadron 1mm Fe plate Emulsion film Structure: OPERA ECC = DONUT ECC Material : Lead Iron Better performance for physics analysis Test for the OPERA technology Roberto Petti

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45 Long decay topology: Long decays Search for a kink with an angle q kink > 20 mrad leptonic channels hadronic channels t fi e, m t fi h, r kink P q kink Require large P T = P*q kink at 2ry vtx. leptonic channels > 100, 250 Mev/c hadronic channels > 600, 300 Mev/c n m NC t Additional kinematic cuts at 1ry vtx. for the hadronic channels F t-h > p/2 P t miss < 1 GeV/c 1 t p/2 n m NC Φ τ-h P t miss (GeV/c) Roberto Petti

46 Short decay topology: emulsion film plastic base At least two additional 1ry tracks for vertex reconstruction P > 1.0 GeV/c I.P. Pb P Require a large impact parameter I.P. > 5 to 20 mm Short decays leptonic channels t fi e, m Signal Additional kinematic cuts on minimal mass/p T for n e CC/charm rejection (P T ) min > 50 Mev/c t fi e (M inv ) min > 3 GeV/c t fi m 80% 0.2% Background Roberto Petti Mass (GeV/c 2 )

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48 Experimental sensitivity (5 years, 1.8kt): 90 % CL upper limit obtained on average by a large ensemble of experiments, in the absence of signal events Dm 2 < 1.2x10-3 ev 2 at full mixing sin 2 (2q) < 5.7x10-3 at large Dm 2 Uncertainties on background (±33%) and on efficiencies (±15%) included Roberto Petti

49 Probability of ns significance: Schematic view of the Super-K allowed region Simulate a large number of experiments with oscillation parameters generated according to the Super-K probability distribution Dm 2 22% 68% 9% N ns events are required for a ns significance Evaluate the fraction P ns of experiments observing N ns events sin 2 2q N 4s = 6 Run P 3s (%) P 4s (%) 3 y P 4s 5 y Distribution of events observed Roberto Petti

50 THE ICARUS DETECTOR Basic element T600 LAr modules (TPC) Proposed baseline T * T1200 (3000 t) electronics, cooling, etc. T1200 T1200 T600 Cross section Roberto Petti T600 First T600 constructed and tested

51 THE T600 DETECTOR View of the inner detector 4 m 4 m 20 m LAr Cryostat (half-module) Roberto Petti

52 2 Data from T600 Drift coord. (m) 1 Full 2D View from the Collection Wire Plane Wire coord. (m) El.m. shower Zoom views 2 m stop and decay in e Run Evt 12 3 Roberto Petti El.m. shower Detail of a long (14 m) m track with d-ray spots

53 2 Drift Coord. (m) Full 2D view from the Collection Wire Plane Wire coord. (m) Zoom View 3.9 m 1.3 m Run Evt 7 Roberto Petti Large el.m. shower

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