n Physics at UCL MINOS and NEMO-III Ruben Saakyan UCL Sheffield Particle Physics seminar 12 November 2003
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n Physics at UCL MINOS and NEMO-III Ruben Saakyan UCL Sheffield Particle Physics seminar 12 November 2003 Motivation Neutrino Mixing Observed ! ne Ue1 n U1 n U1 Ue2 U 2 U 2 Ue3 n1 U 3 n2 U 3 n3 From KamLAND, solar n and atmospheric n 0.5 U 0.61 0.61 VERY approximately 0.87 0.35 0.35 0 0.71 0.71 2 mLMA 5x10 5 eV 2 (7 meV)2 2 matm 3x10 3 eV 2 (55 meV)2 Neutrino MASS What do we want to know? • Relative mass scale (n-osc) • Mass hierarchy (n-osc and bb) • Absolute mass scale (bb+3Hb) mmin ~ 0 - 0.01 eV mmin ~ 0.03 - 0.06 eV Dirac or Majorana n preferred by n theorists n n (see-saw) n or n Only from bb ne n1 n2 n3 Ue12 Ue22 Ue32 From n-osc Mixing MINOS outline MINOS basics Construction status and schedule Atmospheric n’s Physics reach Why ? Confirm SuperK with controlled n beam (K2K is first here) Demonstrate oscillatory behaviour Make first ever precise (10%) measurement of oscillation parameters Dm232, sin2 2q23 Improving existing result (CHOOZ) on subdominant n ne (Ue3) Who ? Main Injector Neutrino Oscillation Study 32 institutions 175 physicists Where and How ? NearDet ~1kT 735km FarDet ~5.4kT Two functionally identical magnetized steel/scintillator sandwich calorimeters How ? (Part II) Expected event spectrum (from NearDet) Observed event spectrum (from FarDet) Ratio: survival probability as a Function of energy Shape: Oscillations? Decay? Other? Mixing angle Dm2 NuMI beam # protons on target 5 year plan Year 2005 2006 2007 2008 2009 Total Protons 2.5 3.8 5.0 6.5 7.2 25 ( × 1020) Lots of work to make it possible n CC events/8×1020 pot (~2.5 yr) Low 5,080 Medium High 13,800 29,600 Construction @ Fermilab. The Beam Decay pipe is finished Horns in fabrication Tunneling is finished and encased in concrete • NuMI beamline completed Dec 2004 • Jan-Mar 2005 – Beam commissioning • Apr 2005 – Start of physics running October’03: Target Hall outfitting complete Beneficial occupancy of Near Detector hall – January 2004 677 m decay pipe Target Near Detector Detector Technology • 1” thick steel planes • Extruded plastic scintillator strips • XY orientation of scint planes • WLS fiber + Hamamatsu multianode PMTs: M16 (Far) and M64 (Near) • <B> = 1.5 Tl (Far and Near) • Front-ends VA(IDE) – M16 QIE – M64 • Software trigger MINOS Far Detector •8 m octagonal 1” steel plates • 2 Supermodules 15 m each • 5.4 kT total mass • 484/485 scintillator/steel planes • 2-ended readout • 8X optical multiplexing • ~1000 Km of scintillator ~2000km of WLS + clear fiber ~26000m2 of active detector planes • <B> ~ 1.5 Tl • DE/Ehadronic 55%/E DE/Eem 22%/E • DP/P 12% (by curvature) 6% (by range) Far Detector at Soudan Completed July 2003 Magnetized and running Half the detector has been running since mid 2002 Fully commissioned Taking atmospheric neutrino data, Soudan 2 exposure by the end of next year Cosmic ray muons Reconstructed front view Cosmic ray muons are used for calibration (and physics!) 2.6ns/plane timing resolution permits direction determination Veto shield tags incoming “parallel” muons which can mimic neutrino events Timing Atmospheric n’s at FarDet Veto Shield Veto shield to veto vertical muons and reduce background Veto shield Upward muons Downward Timing allows measurement of 1/b Good separation of downward (cosmic ray) and upward (neutrino induced) muons Upward Atmospheric n events at FarDet • Atmospheric n interactions have been observed • B-field allows to measure muons up to 70 GeV • B-field gives charge info: distinguish n and nbar • Potential to test CPT Num of events in 5 years n Contained vertex with 620 Upgoing 280 nbar 400 120 700 MeV muon Near Detector n target • ~1 kT • High rates ~ 3 MHz • 3.8 x 4.8 “squeezed” octagon • 1-end readout • no-multiplexing • 220 M64s QIE-based front-end •282 steel planes •153 scintillator planes • Use events with R<30cm EnNear EnFar ninteractions in ND ~10 – 100 n events/spill ~108 – 109 events/yr Unique opportunity for n-scattering physics spectrometer Construction @ Fermilab Near Detector • All NearDet planes assembled and ready to install • Beneficial occupancy of NearDet Hall – Jan 04 • Installation starts January 04 • Installation complete – Oct 04 Calibration Detector at CERN • Both ND and FD too big to be calibrated in test beam • CalDet is the same but smaller • T7 and T11 beamlines at CERN PS in 2001, 2002, 2003 • October 2003: Data taking programme complete Understand detector response to p, e, , p of 0.5 – 10 GeV (particle ID) Calibrate out Near/Far readout differences Debug detector subsystems Refine topology and pattern recognition software 60 planes (1m×1m) 12 ton 24 strips/plane, XY orientation in consecutive planes FarDet and/or NearDet readout Calibration Detector Events Pion 2 GeV 1 GeV Strip Strip Plane Even Plane view 3.5 GeV Plane 2 GeV 1 GeV Odd Plane view Relative Pulse Height 3.5 GeV Odd Plane view Relative Pulse Height Even Plane view Proton Calibration Detector Results Very preliminary MINOS: Physics Reach n n 2.3 yr* 3.7 yr* 5.0 yr* * Times according to 5 year proton intensity plan MINOS: Physics Reach n ne Summary The MINOS Far Detector is complete and taking cosmic and atmospheric n data Beam work and Near Detector construction at FNAL is on schedule. First beam – end 2004. Calibration Detector programme at CERN complete Physics running with NuMI n’s – April 2005 NEMO NEMO Outline bb decay basics The NEMO-III detector First results Sensitivity by 2008 Towards NEMO-NEXT bb decay basics In many even-even nuclei b-decay is energetically forbidden n SM Requires Majorana mn ≠ 0 e e p n n p 2- n 76 n As e n 0+ p e n p 76 Ge Two Neutrino Spectrum Zero Neutrino Spectrum 1% resolution (2 n) = 100 * (0 n) 0+ bb Qbb 2+ 0+ 76 Se This leaves bb as the allowed decay mode 0.0 0.5 1.0 1.5 Sum Energy for the Two Electrons (MeV) 2.0 Qbb bb Decay Basics. Rates 2n 1/ 2 T 0n 1/ 2 (0 0 ) + + 1 1 2n G ( E0 , Z ) M 0n T (0 0 ) G ( E0 , Z ) M + + 2n 2 0n 2 mn 2 G – phase space, exactly calculable; G0n ~ Qbb5, G2n ~ Qbb11 M – nuclear matrix element. Hard to calculate. Uncertainties factor of 2-10 (depending on isotope) Must investigate several different isotopes! <mn> is effective Majorana neutrino mass Isotopes of Interest 48Ca, 76Ge, 100Mo, 150Nd,136Xe, 116Cd, 96Zr, 82Se,130Te Currently Active Experiments NEMO-3 (Tracking calorimeter) CUORICINO (bolometer) <mn> = 0.4 eV ??? Heidelberg-Moscow exp is still running ??? Neutrino Ettore Majorana Observatory 40 physicists and engineers 13 Laboratories/Universities 7 Countries UK NEMO team (so far) Phil Adamson, Leo Jenner, Ruben Saakyan, Jenny Thomas (all UCL) Received approval from PPRP 27 Jan 03 Main involvement: data analysis.. ..and some hardware tasks: PMT helium tests, light injection optimization Expect to participate in shifts at Frejus • From scintil detector: s = 250 ps • From tracker: s||= 1cm s = 0.45mm (using timing information on plasma propagation) Calibration: • Laser survey • neutron Am/Be for s||, s, e+ signature • e- 207Bi, 90Sr for energy calibration • 60Co for time alignment Trigger: 1 scintillator hit > 150 keV + 1 track: few Geiger planes (flexible 3 – 7 Hz) How it works NEMO bb events 3D pictures study single electron spectra study angular distributions Detailed 2ninformation O (105) 2n 100Mo events/yr ! 7 isotopes NEMO background events e+e- e- (~7 MeV) from n Data taking June 2002: start with all 20 sectors, iron shielding, neutron shielding but… …still a lot of debugging (both tracking detector and calorimeter) 14 February 2003: start of routine data taking NEMO-3 First Results 100Mo 1200 h 2n: T1/2=[7.4±0.05(stat)±0.8(sys)]×1018yr (19000 events; S/B 50) 0n: 1 event in 2.8 – 3.2 MeV region T1/2 > 1023 yr 90% CL <mn> < 0.9 – 2.1 eV World’s best result for 100Mo Very preliminary (and conservative) from 3800h: T1/2 > 2.3×1023 yr <mn> < 0.6 – 1.4 eV Single State Dominance (SSD) VS Higher order State Dominance (HSD) Simkovic, Domin, Semenov nucl-th/0006084, Phys. Rev. C HSD 1+ 100Tc 0+ SSD 100Mo 0+ 1. 2. 3. 4. 100Ru single e- spectrum Shape of Shape of 2b spectrum Angular distribution ~ 20% difference in T1/2 100Mo + NEMO-like detector can test it experimentally ! NEMO-3 First Results 100Mo 1200 h single e- spectrum Angular distribution between two e- Preliminary: SSD is preferred NEMO-3 First Results Other Isotopes 150Nd 116Cd T1/2=[8.2±0.4(stat)±0.8(sys)]×1019 T1/2=[7.0±0.7(stat)±0.7(sys)]×1018 T1/2=[3.9±0.3(stat)±0.4(sys)]×1019 T1/2 > 4 × 1022 y 90% CL World’s best result ! T1/2 > 7.7 × 1020 y T1/2 > 1.0 × 1022 y 82Se 90% CL 90% CL NEMO-3 0nbb sensitivity 5 years 100Mo E = 2.8 – 3.2 MeV 7 kg Qbb =3.034 MeV External BG: 0 Internal BG: radioactivity < 0.04 event/y/kg 2nbb= 0.11 event/y/kg T1/2 > 3 × 1024 yr <mn> < 0.2 – 0.5 eV 82Se 1 kg Qbb =2.995 MeV External BG: 0 Internal BG: radioactivity < 0.01 event/y/kg 2nbb= 0.01 event/y/kg T1/2 > 1 × 1024 yr <mn> < 0.6 – 1.2 eV In case of full load of 82Se (~14kg) <mn> < 0.1 – 0.3 eV T1/2(2n) and Energy Resolution T1/2n2 ( 82Se) ~ 10 2n 100 T1/ 2 ( Mo) 82Se looks most promising candidate F ~ (sE/E)6 SuperNEMO ~ 100 kg 82Se (or other) Sensitivity <mn> ~ 0.03 eV in 5 yr 4 supermodules, planar geometry Feasible if: a) BG only from 2n (NEMO3) b) DE/E = 5-6% at 3 MeV (Qbb 82Se) (R&D needed) Future bb projects comparison 5yr exposure * Experiment Source and Mass Sensitivity to T1/2 (y) 3×1027 Sensitivity to <mn> (eV)* Majorana $50M CUORE $25M EXO $50M-100M SuperNEMO $20M 76Ge, 2×1026 0.03 – 0.10 136Xe 8×1026 0.03 – 0.10 1 ton 82Se(or other) 100 kg 2×1026 0.03 – 0.07 500kg 130Te, 0.02 – 0.06 750kg(nat) 5 different latest NME calculations Concluding Remarks First (preliminary) results from NEMO-III: <mn> ≤ 0.6 eV after 3800h 2n: SSD is preferred NEMO-III to reach 0.1 – 0.3 eV with 10 – 14 kg 82Se upgrade UK involvement: 1000cm3 HP Ge detector bb excited states physics with this Ge detector Happy to collaborate with Sheffield and Boulby Concluding Remarks II SuperNEMO sounds very promising. Sensitivity ~ 0. 03 eV with 100kg 82Se Feasibility tested with NEMO-III Boulby is a great potential site for SuperNEMO Opportunity for UK leadership 3-5 December in Orsay: 1st meeting to form SuperNEMO collaboration – ALL WELCOME BACKUP n beam systematics Pointing at right place ? • Beam Monitors • GPS and laser survey Do we know the n spectrum and rates ? Near Det What about spectra differences at Near and Far sites ? Far Det MIPP – a hadron production expt MINOS Calibration Cosmic muons • strip-to-strip calibration Muon Energy Unit (MEU) • relative calibration between ND and FD (stopping muons) Energy Calibration goal: • 5% absolute Light Injection • PMT gain drift • 2% relative between ND and FD • PMT/electronic non-linearity Calibration Detector • Converts MEU to GeV • Topology and pattern recognition Pure materials: Source foils measured with the NEMO-3 detector • 208Tl < 2 Bq/kg • 214Bi < 2 Bq/kg • neutrons < 10-9 n cm-2s-1 Radon in the detector • 222Rn ~ 20 mBq/m3 • 220Rn ~ 1.6 mBq/m3 to be improved with new anti-radon system