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θ 23 - experiments. Introduction Atmospheric neutrinos Super Kamiokande Soudan2 Macro Long Baseline, accelerator K2K Minos CNGS Numi Off-axis JHF Summary. Neutrino Oscillations. Weak  Mass eigenstates. where. i.e. Majorana => 2 extra phases, α 1 , α 2. m 3. Δ m 2 13. m 2. - PowerPoint PPT Presentation

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  • 23 - experimentsIntroductionAtmospheric neutrinosSuper KamiokandeSoudan2MacroLong Baseline, acceleratorK2KMinosCNGSNumi Off-axisJHFSummary

  • Neutrino OscillationsWeak Mass eigenstateswherei.e.Majorana => 2 extra phases, 1, 2

  • Oscillation ProbabilitiesProbability that a of energy E oscillates to b over a path length L isIgnoring CP violation and matter effects, yields 9 probabilitieswhereetce.g.Are the differences in m2 between the mass eigenstates

  • Oscillation AnalysesAtmospheric analyses mostly perform a 2 oscillation analysisFrom the evidence we know atmospheric oscillations are -> and 13 is small so this is a good approximation.Strictly, need to perform a 3 oscillation analysis to extract 23. Such analyses are starting to be used basically to get at 13

  • Atmospheric NeutrinosMean E ~ 1GeV10 < L< 13000 km0.5 < m2 < 10-4 eV2

  • Super KamiokandeKamioka Mine, Japan2700mwe overburden50kton water Cerenkov(32kton inner, 18kton outer)22.5 kton fiducial volume1489 day exposure11,146 PMTs (inner)1885 PMTs (outer)The dominant detector in this field!

  • SuperK eventsFully contained e , ~ 2 GeVPartially contained e , (primarily ) ~ 10 GeVUpward going stopping ~ 10 GeVUpward through going ~ 100 GeV detection 4 event types Good particle ID (muon-like, electron-like)

  • SuperK Event Summary

  • SuperK Zenith Angle Distributionse

  • SuperK - fits - oscillation fit

    90% C.L.1.6 10-3 < m2 < 3.0 10-3 eV2sin22 > 0.92

    Best Fitm2 = 2.5 10-3 eV2sin22 = 1.02min = 163.2/170 d.o.fNo oscillations fit

    2min = 465.5/170 d.o.f

  • SuperK 3-flavour oscillation analysisAssuming m212= m2sol
  • SuperK 3-flavour oscillation analysisBest fit sin223 = 1.0

  • Soudan22100 mwe underground in Soudan Mine, Minnesota963 ton modular fine grained tracking calorimeter with active shieldHigh resolution picture quality eventsComplementary to SuperKData taking ended June 20015.9 fiducial kiloton-years exposure

  • Soudan2 Neutrino EventsHigh resolution reconstructionFully (FCE) and Partially (PCE) contained events used in the analysisHiRes sample used for L/E analysis

  • Soudan2 L/EPCEFCEHiResMaximal oscillations data from two data samples

  • Soudan2 Oscillation Parameters(Feldman-Cousins Analysis)Likelihood fit to m2 ,sin2 2 Confidence level contourssin2 2Log10 m2 (eV2)95%90%68%

  • MACROGran Sasso Laboratory, Italy5.3 kton detector, High acceptance500ps timing, 1 angular resolutionE from multiple scattering, dE/dX events & upward s - detection only

  • MACROResultsSuper-KamiokandeSoudanMacro HEMACRO LEMACRO - Limits on m2 , sin22

  • Atmospheric LimitsSummary

    (SuperK) Best Fit

    m2 = 2.5 10-3 eV2sin22 = 1.0

  • K2KThe first long baseline experiment12 GeV PS @ KEK, 5.1019 potE ~ 1.3 GeV, 99% 250 kmFar Detector Super KamiokandeNear Detector(s) at KEK250km baselineMeasure reduction, spectrum distortion

  • K2KNear Detector(s)Accurate measurement of beam flux and composition

  • K2K EventsBeam events in SK cleanly identifiedAtmospheric BG < 10-3 eventsOscillation Analysis

    Fit to

  • K2K LimitsAllowed regionP(no oscillations) = 1%

    90% CL

    m2 = 1.5-3.9 10-3 eV2at sin22 = 1.0

    Best Fit Parameters

    m2 = 2.8 10-3 eV2sin22 = 1.0

  • MINOSHigh intensity beam from Fermilab to Soudan (Mn)120GeV p, 4.1013 ppp, 4.1020 p/yr, 1.9s rep, 8s spillFlexible beam adjustable energy spectrumTwo detectors, Near (1kT) and Far (5.4kT)Calibration detector (mini-minos) @ CERN735.3 km baseline1 km wide at soudan

  • MINOS BeamNUMI beam a feature of MinosTune beam spectrum by moving 2nd horn relative to targetFirst beam, Dec 2004

  • MINOS DetectorsMinos Far DetectorSite: Soudan, Minnesota, 735kmMagnetised, tracking calorimeter. B ~ 1.3T2 Supermodules, 484 planes, 5.4 kton2.5cm thick steel, 4x1 cm scint. stripsSoftware triggering (flexible)GPS to synch ND/FD dataVeto shield (top/sides) being installedInstallation complete, May/June 2003Data taking since ~ Sep 2001Minos Near DetectorSite: Fermilab, ~ 1kmSmall Far detector1kton , 153 planes~ 1km awayPre-assembly at FNAL ready for installationHigh n rate, ~ 50/spillProspects for non-oscillation n physicsInstallation complete ~ Oct 2004

    nmnmnm

  • MINOS Far DetectorInstallation complete May/June 2003MINOSSoudan 2/CDMS IIshaft

  • MINOSOscillation parameter measurement - nm disappearanceoscillatedunoscillatedm2 nm CC events

    Reconstruct nm energy

    Compare Near (no osc.) with Far energy spectrum

    sin22 , m2 measurement from oscillation minimumCC Energy Distributions

  • MINOSSensitivity from nm disappearanceThese plots are for a 10 kton-year exposure

  • MinosA word on atmospheric neutrinos90% CLData taking with Minos FD now Night/Weekend running during installationShield (top/sides) being installed Atmospheric analysis under wayMagnetic field separation of + , -Not dramatic measurementBut Interesting measurement is comparison between neutrino / anti-neutrinoAssumes Super-K value of m2, sin22Fit to L/E (shape+norm)Minos reconstruction software (prelim)Preliminarysin22

  • CERN to Gran Sasso (CNGS)Aimed at , e appearanceExperimentsOPERAICARUS from CERN to Gran Sasson flux @ Gran SassoBaseline = 732 km400GeV SPS protons7.6 1019 pot/year = 17 GeVOptimised for appearanceBeam by 3rd quarter 2006

  • OPERA ExperimentBrieflysuper module1.77 kton206336 bricksLead-emulsion bricksAim: appearance

  • OPERA sensitivity* assuming the observation of a number of events corresponding to those expected for the given m2 Very little (no) information on sin22 Probability to observe SuperK signal

    years

    P3

    P4

    3

    93%

    83%

    5

    96%

    91%

  • ICARUS ExperimentBrieflyLiquid Argon TPCBubble chamber like 3D imagingAbsolute timing and trigger from LAr scintillation lightAmbitious, multi-purpose detector

  • ICARUSThat Event

  • ICARUSSensitivityAtmosphericBeam- -

  • Off Axis ExperimentsNumiBernstein (hep-ex/0212042)90% CLComparison to Minos capabilityNUMI beam at an off-axis siteNew off-axis detector under design(some assumptions made in this plot)Primary Aim : 13 measurementSee talk by Alfons Weber at this meeting for details on Numi off-axis project

    Sensitivity to m2 similar to MinosSensitivity to 23 a little better

  • Off Axis ExperimentsJHF - OverviewSuper-K: 50 ktConventional beam of ~ 1GeVHyper-K: 1MtThis project and 13 covered in detail later by Dave WarkAim for precision measurement of m223, 23

    NB 13 !!

  • JHFSensitivity to m223, 23 d(Dm232 ) ~ < 110-4 (~4%)d(sin22q23) ~ 0.01 (~1%)Phase I, 5 year run

  • Dreaming of ..Very long baseline projectsJapan ChinaBrookhaven S. Dakota/Soudan/... . . . . . . . Neutrino FactoryFocus on q13 , CP violation and high precision measurements

    Not discussed here

  • SummaryClear effect in atmospheric neutrinosObserved by very different experiments in different locations - oscillation supported by first long baseline expt (K2K)Physics is being measured!Best parameter measurement is currently from SuperKsin22 > 0.92 @ 90% CL. Best Fit Value sin22 =1.

    Precision confirmation and improved measurements with controlled beam over next few years (Minos)JHF + 5 years => measurement at ~ 1%Far Future very long baseline, neutrino factory in design, R&D phase

    23 is close to maximal. How close? Why? Is it actually /4 !