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SNOW 2006, StockholmNEMO 3 and SuperNEMO experiments Vladimir Vasiliev, UCL 2-6 May ’06, Stockholm on behalf of NEMO and SuperNEMO collaborations NEMO.

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Presentation on theme: "SNOW 2006, StockholmNEMO 3 and SuperNEMO experiments Vladimir Vasiliev, UCL 2-6 May ’06, Stockholm on behalf of NEMO and SuperNEMO collaborations NEMO."— Presentation transcript:

1 SNOW 2006, StockholmNEMO 3 and SuperNEMO experiments Vladimir Vasiliev, UCL 2-6 May ’06, Stockholm on behalf of NEMO and SuperNEMO collaborations NEMO collaboration: IReS, Strasbourg, France; LAL, Orsay, France; INEEL, Idaho Falls, USA; ITEP, Moscow, Russia; CENBG, Bordeaux- Gradignan; JINR, Dubna, Russia; IEAP, Prague, Czech Republic; UCL, London, UK; LPC, Caen, France; Saga Universityt, Japan; LSCE, Gif-sur- Yvette, France; Jyvaskyla University, Finland; MHC, South Hadley, USA; Charles University, Prague, Czech Republic; Manchester University, UK. SuperNEMO collaboration: CENBG Bordeaux-Gradignan; IReS, Strasbourg, France; LAL, Orsay, France; LPC, Caen, France; LSCE Gif- Sur-Yvette, France; Jyvaskula Uiversity, Finland; Saga University, Japan; Osaka University, Japan; Fes University, Marocco; INR RAS, Moscow, Russia; ITEP, Moscow, Russia; JINR, Dubna, Russia; RRC Kurchatov Institute, Moscow, Russia; Charles University, Prague, Czech Republic; Technical University, Prague, Czech Republic; Manchester University, UK; UCL, London, UK; ISMA, Kharkov, Ukraine; INEEL Idaho Falls, USA; Mount Holyoke College, USA; University of Texas, USA; IFIC, Valencia, Spain; Canfranc laboratory, Zaragosa, Spain; NEMO 3 and SuperNEMO experiments

2 SNOW 2006, StockholmNEMO 3 and SuperNEMO experiments Neutrinoless  decay Experimental signature: a)2 electrons b)E  + E   Q  NEMO 3. Tracking experiment a) and b). Better signature, control and suppression of background. But worse resolution. Ultimate background –  decay tail.

3 SNOW 2006, StockholmNEMO 3 and SuperNEMO experiments 3 m 4 m B (25 G) 20 sectors NEMO-3 detector Frejus underground laboratory 4800 m.w.e. Source : 10 kg of  isotopes, foil ~ 50mg/cm 2 Tracking detector : drift wire chamber operating in Geiger mode (6180 cells) Gas: He + 4% ethyl alcohol + 1% Ar + 0.1% H 2 O  xy =0,6 cm;  z =1,3 cm; Calorimeter : 1940 plastic scintillators coupled to low radioactivity PMTs FWHM=14% (5”); 17% (3”) @ 1MeV Time resolution = 0.25 ns @ 1MeV  detection efficiency ≈ 50 % Magnetic field: 25 Gauss (3% e+/e - confusion @ 1 MeV) Gamma shield: Iron (e = 18 cm) Neutron shield: 30 cm water + boron (ext. wall); 40 cm wood (top and bottom) Able to identify e , e ,  and 

4 SNOW 2006, StockholmNEMO 3 and SuperNEMO experiments  isotope foils scintillators PMTs Calibration tube Cathodic rings Wire chamber

5 SNOW 2006, StockholmNEMO 3 and SuperNEMO experiments 100 Mo 6.914 kg Q  = 3034 keV 82 Se 0.932 kg Q  = 2995 keV 116 Cd 405 g Q  = 2805 keV 96 Zr 9.4 g Q  = 3350 keV 150 Nd 37.0 g Q  = 3367 keV Cu 621 g 48 Ca 7.0 g Q  = 4272 keV nat Te 491 g 130 Te 454 g Q  = 2529 keV  measurement Background measurement  search  isotopes in NEMO-3

6 SNOW 2006, StockholmNEMO 3 and SuperNEMO experiments Background model External background Detector radioactivity (PMT, iron,  flux from lab). Measured by  Compton scattering in the foil. Radon in tracking chamber 214 Bi pollution of wires and foil surfaces. Measured by delayed 214 Po  -decay. Source foil Internal radioactivity. e and e  events from foil.  decay Cu foil

7 SNOW 2006, StockholmNEMO 3 and SuperNEMO experiments Radon free air facility compressor 9-10 bar buffer dryer adsorption unit @ -50°C cooler & heater 15 Bq/m 3 15 mBq/m 3 In the tent around NEMO 3 Rn = 150 mBq/m 3 In the tracker Rn = 4.5 mBq/m3  does not depend any more from Rn level in the tent. 2 sets of data Phase-I, before 4/10/04, Rn ≈ 22.2 mBq/m3, Phase-II, Rn=4.5 mBq/m3

8 SNOW 2006, StockholmNEMO 3 and SuperNEMO experiments  results for 100 Mo T 1/2 = 7.11  0.02 (stat)  0.54 (syst)  10 18 y Phys Rev Lett 95, 182302 (2005) SSD model confirmed HSD, higher levels contribute to the decay SSD, 1  level dominates in the decay (Abad et al., 1984, Ann. Fis. A 80, 9) 100 Mo 00 100 Tc 11 Decay to the excited 0 + state of 100 Ru T 1/2 = 5.7  1.3 (stat)  0.8 (syst)  10 20 y To be published soon  Phase I + II ( 587d) Use MC Limit approach: shape information, different background level for PI and PII E 1 +E 2 >2 MeV 12952 evs MC = 12928 ± 70    T 1/2 > 5.6∙10 23 y, 90% CL Window method [2.78-3.20] MeV, (690d) 14 evs MC = 13.4   =8.2 % T 1/2 > 5.8∙10 23 y, 90% CL Simkovic, J. Phys. G, 27, 2233, 2001 Single electron spectrum different between SSD and HSD E single (keV) SSD simulation

9 SNOW 2006, StockholmNEMO 3 and SuperNEMO experiments  results for 82 Se T 1/2 = 9.6  0.3 (stat)  1.0 (syst)  10 19 y Phys Rev Lett 95, 182302 (2005)  Phase I + II ( 587d) Use MC Limit approach E 1 +E 2 >2 MeV 238 evs MC = 240.5 ± 7    T 1/2 > 2.7∙10 23 y, 90% CL Window method [2.62-3.20] MeV, (690d) 7 evs MC = 6.4   =14.4 % T > 2.1∙10 23 y, 90% CL

10 SNOW 2006, StockholmNEMO 3 and SuperNEMO experiments  decay for other isotopes 116 Cd, T 1/2 =(2.8±0.1(stat)±0.3(syst))∙10 19 y 150 Nd, T 1/2 =(9.7±0.7(stat) ±1.0(syst))∙10 18 y 96 Zr, T 1/2 =(2.0±0.3(stat)±0.2(syst))∙10 19 y 48 Ca, T 1/2 =(5.3±0.9(stat)±0.5(syst))∙10 19 y Very preliminary results, to be crosschecked and published soon

11 SNOW 2006, StockholmNEMO 3 and SuperNEMO experiments Exotic processes search V+A current in electroweak lagrangian Neutrino coupled axions  (majorons) V+A * n=1 ** n=2 ** n=3 ** n=7 ** Mo >3.2∙10 23 <1.8∙10 -6 [1] >2.7∙10 22 g<(0.4-1.8)∙10 -4 [3] >1.7∙10 22 >1.0∙10 22 >7∙10 19 Se >1.2∙10 23  2.8 ∙ 10 -6 [2] >1.5∙10 22 g<(0.7-1.9)∙10 -4 [3] >6.0∙10 21 >3.1∙10 21 >5.0∙10 20 * new PI+PII data ** R.Arnold et al. Nucl. Phys. A765 (2006) 483 NME Calculations: [1] J. Suhonen, Nucl. Phys. A 700 (2002) 649 [2] M. Aunola and J. Suhonen, Nucl. Phys. A 463 (1998) 207 [3] F. Simkovic et al., Phys. Rev. C 60 (1999) 055502; S.Stoica and H. Klapdor-Kleingrothaus, Nucl. Phys. A 694 (2001) 269; O. Civatarese and J. Suhonen, Nucl. Phys. A 729 (2003) 867

12 SNOW 2006, StockholmNEMO 3 and SuperNEMO experiments SuperNEMO project extension of NEMO 3 technique 100 kg of isotopes, thin source between tracking volumes, surrounded by calorimeter. sensitivity 1-2∙10 26 y, 40-70 meV main improvements needed: energy resolution (8% FWHM @ 1MeV ≡ 4% @ 3MeV) detection efficiency (factor 2) source radio purity (factor 10) background rejection methods

13 SNOW 2006, StockholmNEMO 3 and SuperNEMO experiments SuperNEMO milestones 2006-8: Design study Calorimeter Tracker Source Site selection (Frejus, Gran Sasso, Canfranc, Bulby) Approved and funded R&D program in UK and France. Spain, Russian and Japan groups applied for funding. end 2008: Full Proposal 2009 – 2011: Production 2010-2011: Start taking data 2015: planned sensitivity ~0.04 eV

14 SNOW 2006, StockholmNEMO 3 and SuperNEMO experiments Modular design Top view Side view 5 m 1 m 4 m source tracker calorimeter

15 SNOW 2006, StockholmNEMO 3 and SuperNEMO experiments Alternative design (bar scintillator) Double sided readout

16 SNOW 2006, StockholmNEMO 3 and SuperNEMO experiments Calorimeter R&D so far  7-8% FWHM @ 1MeV for small scintillator 5x5x2 cm  9% FWHM @ 1 MeV for 15x15x2 cm … but because of light guide!  11-13% FWHM @ 1 MeV for 200 cm bar scintillator. Attenuation length 150 cm! looking for better plastic.

17 SNOW 2006, StockholmNEMO 3 and SuperNEMO experiments Wiring robot The challenge: from 6,000 to ~60,000+ cells Wires must be strung terminated crimped This can not be done manually (~10 min/wire) Complications Copper pick-ups Must be cost effective Solder can not be used (radiopurity)

18 SNOW 2006, StockholmNEMO 3 and SuperNEMO experiments BiPo device, ultra low purity msr. Tracking (wire chamber) Shield radon, neutron,  Source foil (40 mg/cm 2 ) Scintillator + PMT 2 modules 2  3 m 2 → 12 m 2 Background < 1 event / month   (300 ns) 232 Th 212 Bi (60.5 mn) 208 Tl (3.1 mn) 212 Po 208 Pb (stable) 36%   (164  s) 238 U 214 Bi (19.9 mn) 210 Tl (1.3 mn) 214 Po 210 Pb 22.3 y 0.021% Bi-Po Process WHY?  spectroscopy doesnt sensitive to purity level required ~10  Bq/kg  delay ee Q  ( 214 Bi)=3.2 Me Q  ( 212 Bi) = 2.2 MeV ee e  prompt  T 1/2 ~ 300 ns E deposited ~ 1 MeV Delay 

19 SNOW 2006, StockholmNEMO 3 and SuperNEMO experiments Isotope choice Detector allows to hold any isotope. Choice depends on: - enrichment possibilities. Obligatory! - Q  value (phase space factor, background) -  life-time 82 Se good candidate  100 kg per 2-3 y enrichment rate possible in Russia  Q  = 2995 keV. Concern about 214 Bi and 208 Tl only.  test 2kg sample produced. Under purification now 150 Nd even better !  SILVA group (SACLAY, France) was contacted. 150 Nd enrichment is possible!  Q  = 3367 keV. Concern about 208 Tl only  Large phasespace. 2  tale only 1.6 bigger then for 82 Se  NME & G  much better then for 82 Se

20 SNOW 2006, StockholmNEMO 3 and SuperNEMO experiments Conclusion NEMO 3 is continuing to take data no  signal so far. 100 Mo: T 1/2 >5.8∙10 23 y ; m <0.6-1.0 eV * 82 Se: T 1/2 >2.1∙10 23 y ; m <1.2-2.5 eV * * F. Simkovic et al., Phys. Rev. C 60 (1999) 055502; S.Stoica and H. Klapdor- Kleingrothaus, Nucl. Phys. A 694 (2001) 269; O. Civatarese and J. Suhonen, Nucl. Phys. A 729 (2003) 867 a number of  results to be published soon SuperNEMO R&D is in progress. 3 year program funded in UK and France.

21 WE ARE IN THE MIDDLE OF THE ROAD

22 EXIT THAT COULD LEAD BEYOND SM thank you for your attention!


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