Long Baseline Neutrino Oscillation Experiments

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1 Long Baseline Neutrino Oscillation Experiments Alfons Weber University of Oxford XXXVIIth Recontre de Moriond "Electroweak Interactions and Unified Theories" Les Arcs, Savoie, France March 9-16, 2002

2 Contents Introduction Long baseline experiments K2K MINOS OPERA ICARUS KamLAND The Future SuperBeams Neutrino Factories A. Weber LBL Experiments 2

3 Introduction Several indication for neutrino oscillations Solar neutrino problem Homestake, SAGE, GALLEX Kamiokande, Super-Kamiokande, SNO Atmospheric neutrino problem Kamiokande, IMB, Frejus, NUSEX, Soudan 2, SuperK LSND effect LSND, KARMEN New precision experiments are needed! replace natural with man-made neutrino source tune oscillation distance and energy to problem A. Weber LBL Experiments 3

4 Neutrino Oscillations νe c12c13 c13s12 s13 ν1 iδ iδ ν µ = c23s12e c12s13s23 c12c23e s12s13s23 c13s 23 ν 2 iδ iδ ν τ s23s12e c12c23s13 c12s23e c23s12s13 cc ν 3 with c ij =?mij 2 cos( θij ), sij = sin (? ij ),? ij = mixing angle and = 6 parameter to be determined: 3 angle 2 mass differences 1 CP violating phase Disappearance of atmospheric muon neutrinos: mass difference m L 23 P( νµ ντ) = cos ( θ13)sin ( θ23)sin Eν A. Weber LBL Experiments 4

5 K2K Distance: 250 km Beam Energy: 12 GeV Neutrino Energy: 1.3 GeV A. Weber LBL Experiments 5

6 MINOS Beam travels 730 km to Soudan Minnesota FNAL Main Injector E = 120 GeV 4x10 13 ppp (?) Cycle 2 sec 10 µsec spill Tuneable neutrino Energy Peak at: 3, 7, 15 GeV A. Weber LBL Experiments 6

MINOS Collaboration Around 180 Physicists and Engineers IHEP-Beijing College de France Athens Dubna ITEP-Moscow Lebedev Protvino Cambridge Oxford Rutherford Sussex University College London Argonne

7 MINOS Collaboration Around 180 Physicists and Engineers IHEP-Beijing College de France Athens Dubna ITEP-Moscow Lebedev Protvino Cambridge Oxford Rutherford Sussex University College London Argonne Brookhaven Caltech Chicago Elmhurst Fermilab James Madison Harvard Illinois Indiana Livermore Macalester Minnesota Northwestern Pittsburgh South Carolina Stanford Texas-Austin Texas A&M Tufts Western Washington Wisconsin A. Weber LBL Experiments 7

8 MINOS Far Detector 2 Super-modules 2.7 kiloton each 486 planes of steel and scintillator 96 scintillator strips each plane double sided read-out with multi-anode PMTs Toroidal magnetic field (1.5 T at 2 m radius) Very similar near detector! A. Weber LBL Experiments 8

9 MINOS Scintillator Module WLS Fibers Scintillator Module Optical Connector Optical Connector Multiplex Box Connection to electronics 8 m PMTs Connection to electronics Optical Connector Optical Connector Multiplex Box WLS Fibers Clear Fiber Ribbon Cable (2-6 m) 4-8m scintillator modules strips double sided readout multi anode PMTs (16/64) A. Weber LBL Experiments 9

10 MINOS Plane 2-m wide, 0.5-inch thick steel plates Scintillator plane Orientations alternate ±90 o in successive planes Bottom steel plane layer Top steel plane layer A. Weber LBL Experiments 10

11 MINOS Oscillation Physics Several channels to analyse neutrino oscillations T-Test = #CC / #NC ν µ disappearance ν e appearance (θ 13 ) ν τ appearance Combination of all analysis will reveal mixing parameters m 2 sin 2 2θ flavour? µ hadrons? µ hadrons 1.5 m µ 5 m? µ A. Weber LBL Experiments 11

12 ? µ CC Energy Analysis Select? µ charge current events and reconstruct neutrino energy E E + ν = µ E h range, B field Energy resolution: pµ / pµ = 10% Eh / Eh = 60% / calorimetry Compare energy spectrum in near and far detector Measure? m 2 and sin 2 2? E? m 2 sin 2 2? A. Weber LBL Experiments 12

13 ? µ Disappearance Results A. Weber LBL Experiments 13

14 CNGS Beam Baseline: 730km <E? > = 17 GeV optimised for t appearance CERN Neutrinos to Grand Sasso CERN SPS E p = 400 GeV 4.8*10 13 ppp cycle sec 7.6*10 19 pot/year Experiments ICARUS OPERA try find t by searching for decay kink nuclear emulsion A. Weber LBL Experiments 14

15 OPERA Collaboration METU, Ankara, Turkey LAPP and Université de Savoie, Annecy, France INFN and Bari University, Bari, Italy IHEP, Beijing, China PR Humboldt University,Berlin, Germany Bern University, Bern, Switzerland INFN and Bologna University, Bologna, Italy IIHE (ULB-VUB), Brussels, Belgium Joint Institute for Nuclear Research (JINR), Dubna, Russia Laboratori Nazionali di Frascati, INFN Frascati, Italy Toho University, Funabashi, Japan CERN, Geneva, Switzerland Märkische Fachhochschule FB Elektrotechnik, Hagen, Germany Technion, Haifa, Israel Hamburg University, Hamburg, Germany High Energy Physics Group Shandong University, Jinan, Shandong, China PR Aichi Educational University, Kariya, Japan Kobe University, Kobe, Japan IPNL and Université C.Bernard, Lyon, France INR, ITEP and MEPHI, Moscow, Russia Münster University, Münster, Germany Nagoya University, Nagoya, Japan INFN and "Federico II" University, Naples, Italy LAL and Université Paris-Sud, Orsay, France INFN and Padova University, Padova, Italy INFN and "La Sapienza" University, Rome, Italy Rostock University, Rostock, Germany INFN and Salerno University, Salerno, Italy IRES, Strasbourg, France Utsunomiya University, Utsunomiya, Japan Rudjer Boskovic Institute (IRB), Zagreb, Croatia 29 groups~ 130 physicists A. Weber LBL Experiments 15

cells ) n ~ 10 m n target and t decay detector Each super-module is a sequence of 24 modules

16 The OPERA Experiment super module m spectrometer Magnetised Iron Dipoles Drift tubes and RPCs brick (56 Pb/Em. cells ) n ~ 10 m n target and t decay detector Each super-module is a sequence of 24 modules consisting of - a wall of Pb/emulsion bricks - planes of orthogonal scintillator strips modul e brick wall scintillator strips 8 cm (10X 0 ) A. Weber LBL Experiments 16

17 OPERA Target Section Selected brick Sampling by Target Tracker planes ( X,Y ) Event as seen by the target tracker Brick wall 10 cm p.h. 0 max Selected bricks extracted daily using dedicated robot Emulsion-Scintillator strip Hybrid Target Tracker task select bricks efficiently High scanning power + low background allow coarse tracking A. Weber LBL Experiments 17

18 OPERA Emulsion Brick Origami packed ECC brick for OPERA ν Vacuum packing Protection against light and humidity variations. Keep the position between films and lead plates. Vacuum preserved over 10 years 10X 0 ( 56 emulsion films ) 12.5cm 235k bricks for 3 super modules A. Weber LBL Experiments 18

19 OPERA? t Candidates Long decays reconstruct kink topology Short decays detect large impact parameter track Loose cut to reject low momentum tracks A. Weber LBL Experiments 19

20 OPERA Sensitivity (average 90 % CL upper limit for a large number of experiment in the absence of a signal) 5 years 3 years 5 years data taking Dm 2 = 1.2x10-3 ev 2 at full mixing sin 2 (2q) = 6.0x10-3 at large Dm 2 A. Weber LBL Experiments 20

21 OPERA: m2 90 % CL limits * m 2 ( 10-3 ev 2 ) (mixing constrained by SuperK) Upper limit Lower limit (U - L) / (2*True) 41 % 19 % 12 % OPERA 90 % CL in 5 years N t / year * assuming the observation of a number of events corresponding to those expected for the given Dm 2 Probability to observe SuperK signal years P3s P4s 3 93% 83% 5 96% 91% A. Weber LBL Experiments 21

22 ICARUS Sensitivity atmospheric beam Sensitivity similar to OPERA! A. Weber LBL Experiments 22

23 SuperBeams Use a very intense proton beam dump to produce neutrinos = SuperBeam Low energy (0.2-2 GeV) low? m 2 Medium baseline (~100 km) large rate Massive detectors ( kton) low sin 2 2T Measurement program: Improve? m 2 23, sin 2 2T 23 Measure? 13! Totally unconstrained! Possibility of measuring CP violating phase d! Sites CERN-Modane (SPL, 130 km) Tokaimura-Kamioka (JAERI, 295km) A. Weber LBL Experiments 23

SuperBeams: JHF-SuperK Phase II Increase beam power: 4 MW HyperKamiokande: 1 Mton Possibility of measuring CP-violation, if parameters are right!

24 SuperBeams: JHF-SuperK Phase II Increase beam power: 4 MW HyperKamiokande: 1 Mton Possibility of measuring CP-violation, if parameters are right! No need for?-factory? New beam from JAERI 50 GeV, 0.77 MW 3.3*10 14 ppp / 3.3 sec Phase I approved start operation 2007 Detector exists! A. Weber LBL Experiments 24

25 SuperBeam Physics Sensitivity (phase I)? µ disappearance (1 year) CP violation (phase II) A CP P( ν νe) P( ν µ ν e) µ = P( ν ν ) + P( ν ν ) µ 2 m12l sin2θ 12 = sinδ 4E sinθ ν e 13 Only possible, if KamLAND µ e δ 2 (sin 2 θ23 ) 0.01 δ ( m ) 2 10 ev sin 2θ < confirms LMA! A. Weber LBL Experiments 25

26 KamLAND Sensitivity Measuring? e disappearance! Mostly ruled out by most recent SNO result A. Weber LBL Experiments 26

27 Neutrino Factory Muon storage ring: The Ultimate Neutrino Source A. Weber LBL Experiments 27

28 Neutrino Factory Physics A. Weber LBL Experiments 28

29 Summary Present K2K (nice data until 2001 and later) KamLAND (just started taking data) Future MINOS (cosmics 2001, beam 2005) OPERA (beam 2005) ICARUS (2005, partially approved) JHF-SuperK (2007, not yet approved) Science fantasy Neutrino Factories (2010, at the earliest) A. Weber LBL Experiments 29

A. Chukanov On behalf of OPERA collaboration JINR, Dubna TAUP 2011, Munich, 5-9 september, 2011

A. Chukanov On behalf of OPERA collaboration JINR, Dubna TAUP 2011, Munich, 5-9 september, 2011 Outline OPERA experiment Event location procedure n t candidate Background estimation Conclusion 2 OPERA: