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LAUNCH Workshop Heidelberg 21-22 March 2007. NEMO-3 and SuperNEMO. Xavier Sarazin Laboratoire de l’Accélérateur Linéaire, Orsay Univ. Paris 11, CNRS/IN2P3. NEMO: A tracko-calo detector. b Calorimeter. b. Tracking. Source foils. b. Direct signature of the 2 electrons
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LAUNCH Workshop Heidelberg 21-22 March 2007 NEMO-3 and SuperNEMO Xavier Sarazin Laboratoire de l’Accélérateur Linéaire, Orsay Univ. Paris 11, CNRS/IN2P3
NEMO: A tracko-calo detector b Calorimeter b Tracking Source foils b Direct signature of the 2 electrons 3 observables: - total deposited energy - individual energy - angular corelation Possibility to measure various isotopes Advantages: Ch. Marquet – APPEAL 07 – February 2007
The NEMO3 detector 20 sectors B(25 G) 3 m Magnetic field:25 Gauss Gamma shield:Iron (18 cm) Neutron shield: borated water + wood 4 m Identification e-, e+, g and a @ Frejus Underground Laboratory : 4800 m.w.e. Source: 10 kg of isotopes cylindrical, S = 20 m2, 60 mg/cm2 Tracking detector: Drift wire chamber in Geiger mode (6180 cells) Gas: He + 4% ethyl alcohol+ 1% Ar + 0.1% H2O Calorimeter: 1940 plastic scintillators coupled to low radioactivity PMTs
View of one sector during source installation Cathodic rings Wire chamber PMTs Calibration tube scintillators bb isotope foils
bb decay isotopesin NEMO3 detector bb(2n) measurement 116Cd405 g Qbb = 2805 keV 96Zr 9.4 g Qbb = 3350 keV 150Nd 37.0 g Qbb = 3367 keV 48Ca 7.0 g Qbb = 4272 keV 130Te454 g Qbb = 2529 keV External bkg measurement natTe491 g 100Mo6.914 kg Qbb = 3034 keV 82Se0.932 kg Qbb = 2995 keV Cu621 g bb0n (Enriched isotopesproduced in Russia) 100Mo purified at INL (USA) and ITEP (Russia)
bb events selectionin NEMO3 Transverse view Run Number: 2040 Event Number: 9732 Date: 2003-03-20 Longitudinal view Vertex emission Vertex emission Deposited energy: E1+E2= 2088 keV Internal hypothesis: (Dt)mes –(Dt)theo = 0.22 ns Common vertex: (Dvertex) = 2.1 mm (Dvertex)// = 5.7 mm bb events selection • Trigger: 1 PM > 150 keV • 3 Geiger hits (2 neighbour layers + 1) • Trigger Rate = 5,8 Hz • bb evts: 1 event every 2 minutes • 2 trackswith charge < 0 • 2 PM, eachE> 200 keV • PM-track association • Common vertex • Internal hypothesis Dt~0ns • No isolated PM(g rejection) • No delayed track (214Bi rejection ) Typical bb2n event observed from 100Mo
100Mo bb(2n) Results – Phase 2 8000 7000 6000 5000 4000 3000 2000 1000 0 7000 6000 5000 4000 3000 2000 1000 0 Number of events Number of events/0.05 MeV • Data • Data 22 Monte Carlo 22 Monte Carlo Background subtracted Background subtracted Phase 2 Oct. 2004 – Mar. 2006 LOW RADON Angular distribution Sum energy spectrum 138969 events 6914 g 294 days S/B = 54 138969 events 6914 g 294 days S/B = 54 NEMO-3 NEMO-3 100Mo 100Mo E1 + E2 (keV) Cos() T1/2(bb2n) = 7.15 ± 0.02 (stat) ± 0.54 (syst) 1018 years «bb factory»→ tool for precision test
Other Nuclei bb(2n) Results – Phase 1 48Ca 82Se T1/2 = 10.3 ± 0.2 (stat) ± 1.0 (syst) 1019 y(Qbb=2995 keV) 116Cd T1/2 = 2.8 ± 0.1 (stat) ± 0.3 (syst) 1019 y (Qbb= 2805 keV) 150Nd T1/2 = 9.7 ± 0.7 (stat) ± 1.0 (syst) 1018 y (Qbb= 3367 keV) 96Zr T1/2 = 2.0 ± 0.3 (stat) ± 0.2 (syst) 1019 y (Qbb=3350 keV) 48Ca T1/2 = 3.9 ± 0.7 (stat) ± 0.6 (syst) 1019 y (Qbb =4272 keV) 932 g 389 days 2750 events S/B = 4 82Se Background subtracted
External BKG: 208Tl (PMTs) channel external (e-, g) ~ 10-3 evts y-1 kg -1 2.8<E1+ E2<3.2 MeV External BKG:neutrons and g > 3MeV channel crossing e- or (e-,e+)int with E1+E2> 4 MeV ~ 3. 10-3evts y-1 kg -1 2.8<E1+ E2<3.2 MeV 208Tl in the bb foils : 80 ± 20 mBq/kg Channels (e-,2g), (e-,3g) coming from the foil ~ 0.1 evts y-1 kg -1 2.8<E1+ E2<3.2 MeV 214Bi in NEMO3 0.1 evts y-1 kg -1 2.8<E1+ E2<3.2 MeV Radon in NEMO3 Channel (e-,g,a) in gas or in the foil ~ 1 evt y-1 kg -1 2.8<E1+ E2<3.2 MeV Background radon level suppressed by a factor 10 in Dec. 2004 with the radon-free air purification system 100Mo bb2nT1/2 = 7.15 1018 y ~ 0.3 evts y-1 kg -1 2.8<E1+E2<3.2 MeV Measurements of bb(0n) backgrounds NEMO3 is able to measure each componant of its background by different analysis channels
Two phases of runs in NEMO-3 Phase I: High radon level February 2003 - September 2004 394 days of data taking bb0n publication: Phys. Rev. Lett. 95, 182302 (2005) Phase II: Low radon level December 2004 - today 294 days of data taking have been preliminary analysed (Dec 2004-Mar 2006)
bb(0n) results with 100Mo Phase II, Low radon 299 days Phase I + II 693 days Number of events / 40 keV Number of events / 40 keV [2.8-3.2] MeV: e(bb0n) = 8 % Expected bkg = 3.0 events Nobserved = 4 events 100Mo, 7 kg Phase I, High radon 394 days Number of events / 40 keV [2.8-3.2] MeV: e(bb0n) = 8 % Expected bkg = 8.1 events Nobserved = 7 events T1/2(bb0n) > 5.8 1023 years (90 % C.L.) Phases I + II Expected sensitivity End 2009: T1/2(bb0n) > 2. 1024 years (90% C.L.)
bb(0n) results with 82Se 82Se, 1 kg Phase I, High radon 394 days Phase I + II 693 days Phase II, Low radon 299 days [2.7-3.2] MeV: e(bb0n) = 13 % Expected bkg= 1.2 ± 0.3 Nobserved = 2 evts [2.7-3.2] MeV: e(bb0n) = 13 % Expected bkg= 3.1 ± 0.6 Nobserved = 5 evts T1/2(bb0n) > 1.2 1023 (90 % C.L.) Phases I + II Expected sensitivity End 2009: T1/2(bb0n) > 8. 1023 years (90% C.L.)
From NEMO-3 to SuperNEMO 150Nd or 82Se 100Mo Choice of isotope Energy resolution FWHM (calorimeter) 4% @ 3MeV 8% @3MeV Isotope mass M 100-200kg 7 kg Efficiency e(bb0n) 8 % ~ 30 % Internal radiopurity 208Tl and 214Bi in the bb foils 208Tl < 2mBq/kg (If82Se: 214Bi < 10 mBq/kg) 208Tl < 20mBq/kg 214Bi < 300 mBq/kg T1/2(bb0n) > 2. 1024 y <mn> < 0.3 – 1.3eV T1/2(bb0n) > 1026 y <mn> < 50 meV SENSITIVITY 1) bb source production 3) Radioprurity Main R&D tasks: 2) Energy resolution NEMO-3 SuperNEMO 4) Tracking
SuperNEMO Collaboration ~ 60 physicists, 12 countries, 27 laboratories Japan U Saga KEK U Osaka Marocco Fes U USA MHC INL (U Texas) Russia JINR Dubna ITEP Mosow Kurchatov Institute UK UCL U Manchester Imperial College Finland U Jyvaskula Poland U Warsaw Ukraine INR Kiev ISMA Kharkov France CEN Bordeaux IReS Strasbourg LAL ORSAY LPC Caen LSCE Gif/Yvette Slovakia (U. Bratislava) Spain U Valencia U Saragossa U Barcelona Czech Republic Charles U Praha IEAP Praha
SuperNEMO Design Study February 2006 – February 2009 • Approved in France, UK and Spain. Similar proposals under consideration in Russia, Czech Republic, Japan • Main tasks and deliverables • R&D on critical components • Calorimeter energy resolution of 4% at 3 MeV • Optimisation of tracking detector • Wiring automation • Ultrapure source production and purity control • Sensitivity simulations • Technical Design report • Experimental site selection (Modane (Frejus), Canfranc, Gran Sasso, Boulby)
Possible SuperNEMO design • Source (40 mg/cm2) 4 x 3 m2 • Tracking : drift chamber ~3000 cells in Geiger mode • Calorimeter: Scint. + PMTs ~ 1000 PMTs if scint. Blocs • ~ 100 PMTs if scint. bars 1 module 1 m 5 m Top view Planar and modular design: ~ 100 kg of enriched isotopes 20 modules 5 kg
R&D Scintillators Plastic scintillators (collaboration with Karkhov and Dubna = PICS) - Improvement on polystyrene production - Development of Polyvinylxylene - Geometry and wrapping (chemical treatment Karkhov) Tests in CENBG of different production and size of scintillators with an e- spectrometer Scintillator blocks 6 x 6 x 2 cm3 PMT XP5312B (Photonis) FWHM @ 1 MeV ~ 7% Liquid scintillators - Advantages: high light yield + very good uniformity and transparency - Challenge: mechanical contraints particularly for the entrance window (electron detection) Liq. Scintillator 75 x 75 x 20 mm3 + Light guide + PMT 3" FWHM @ 1 MeV = 7.3 % Photomultipliers - Hamamatsu and Photonis - Large size and Large Quantum Efficiency: QE ~ 45 % for 3" PMTs
1 2 0n T1/2 = G0nM0n‹mn›2 150Nd: a dream for bb0n ? T1/2(0n) avec mn=50meV Shell Model: Caurier et al. QRPA: Feasller Rodin Simkovic Vogel 2005
150Nd: a dream for bb0n ? 100 kg of 150Nd is equivalent to: (efficiency and background constant) If M0v = cte, M0n QRPA 1700 kg of 76Ge 1000 kg of 76Ge 400 kg of 82Se 340 kg of 82Se 400 kg of 130Te 720 kg of 130Te 400 kg of 136Xe 2600 kg of 136Xe Qbb150Nd = 3.367 MeV, Beyond the g of 2.614 MeV from 208Tl Beyond 214Bi Qb = 3.2 MeV
150Nd production: The Laser Method (AVLIS) Enriched U collecting plate Vaporized isotope mixture AVLIS: Atomic Vapor Laser Isotope Separation Selective photoionization based on : isotope shifts in the atomic absorption optical spectra U + 3 selective photons →235U+ + e- Depleted U collecting plate Laser beam
2000 – 2003 Program: MENPHIS Facility Evaporator Dye laser chain Yag laser Copper vapor laser Expression of Interest of SuperNEMO, SNO++ and Japan to keep MENPHYS for Nd enrichment Design : 2001 Building : 2002 1st test : early 2003 1st full scale exp. : june 2003 • Production of 200 kg of enriched U at 2.5 % in few days • Results in agreement with simulation expectation MENPHIS simulation shows that enrichment of 150Nd is doable (ton scale), ~ 100 kg in few weeks !!! 48Ca enrichment is theoriticaly doable. Studies must be done
SNO++ Project Neodinium loaded in Liquid Scintillator in SNO With T1/2(0n) = 1.3 1024 y 1000 bb0n events/y with 1% natural Nd-loaded liquid scintillator in SNO++ simulation: one year of data SNO++ with 1% of 150Nd-loaded = High potential of discovery !!! SuperNEMO + SNO + 150Nd= A unique Tracko-Calo + Calo
Modane(Frejus) (France) Phase II 100- 200 kg (2012) Phase I 20 kg (2010) Canfranc (Spain) Possible location for SuperNEMO
2010 2011 2007 2008 2009 2012 2013 Schedule / cost NEMO3 Running R&D SuperNEMO SuperNEMO 1st module construction Preparation of the site construction of 20 modules 6 SuperNEMO modules running @ Canfranc Final SuperNEMO modules installation • Cost estimate (preliminary) • Isotope: • (10 M€)if 82Se • 20 M€ if 150Nd (AVLIS) • Detector: • 20M€ • Grand Total: 40 - 50 M€ RUNNING of Full detector