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Search for bb0n decay with NEMO 3 and SuperNEMO experiments

Search for bb0n decay with NEMO 3 and SuperNEMO experiments. Vladimir Vasiliev UCL, London, UK on behalf of the NEMO collaboration. SUSY 2007 Karlsruhe, 28 July 2007. Outline. bb decay and SUSY NEMO-3 experiment Overview of the NEMO-3 Highlights of the main NEMO-3 results

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Search for bb0n decay with NEMO 3 and SuperNEMO experiments

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  1. Search for bb0n decay with NEMO 3 and SuperNEMO experiments Vladimir Vasiliev UCL, London, UK on behalf of the NEMO collaboration SUSY 2007 Karlsruhe, 28 July 2007

  2. Outline • bb decay and SUSY • NEMO-3 experiment • Overview of the NEMO-3 • Highlights of the main NEMO-3 results • SuperNEMO project • R&D program • Current status 28 July 2007, SUSY07, Karlsruhe Vladimir Vasiliev NEMO 3/ SuperNEMO experiments 2

  3. bb0n decay, n mass mechanism only possible for Majorana neutrinos with mass > 0 Beyond the SM: Lepton Number Violation ! 28 July 2007, SUSY07, Karlsruhe Vladimir Vasiliev NEMO 3/ SuperNEMO experiments 3

  4. bb decay and SUSY: threelinear terms lepton number violation bb decay amplitude related to (l'111)2 dR+dR → uL+uL+eL+eL exchange with: squarks sleptons neutralinos gluinos 28 July 2007, SUSY07, Karlsruhe Vladimir Vasiliev NEMO 3/ SuperNEMO status 4

  5. bb decay and SUSY: squark mixing contribution from l'1jk possible via left- and right- squark mixing Hirsch,Klapdor-Kleingrothaus, Kovalenko, PLB 372 (1996) 181 Paes, Hirsch,Klapdor-Kleingrothaus, PLB 459(1999) 450 28 July 2007, SUSY07, Karlsruhe Vladimir Vasiliev NEMO 3/ SuperNEMO experiments 5

  6. bb decay and SUSY: radiative neutrino mass neutrino can acquire mass due to SUSY radiactive corrections,l'1kk Gozdz, Kaminski, Šimkovic, PRD 70 (2004) 095005 28 July 2007, SUSY07, Karlsruhe Vladimir Vasiliev NEMO 3/ SuperNEMO experiments 6

  7. NEMO 3: Neutrino Ettore Majorana Observatory • Czech Republic • Finland • France • Japan • Russia • Spain • UK • Ukraine • USA LS Modane, FR Tunnel Frejus 28 July 2007, SUSY07, Karlsruhe Vladimir Vasiliev NEMO 3/ SuperNEMO experiments 7

  8. 20 sectors B(25 G) 3 m 4 m key techniques: tracking, calorimetry, timing NEMO-3 • Goal: reconstruct 2 electrons of the final state • E1 + E2 = Qbb • Particle physics - like approach: • Measure several observables of the final state • Trajectories of 2 electrons • Energies of 2 electrons • Time • Magnetic field curvature ("+" vs "-") • Reconstruct the final state topology and kinematics • Several requirements for candidate events • Topology (vertex, track-scintillator correlation) • Time coincidence • 2-electron invariant mass • Identify e-, e+, g, a • Able to measure backgrounds 28 July 2007, SUSY07, Karlsruhe Vladimir Vasiliev NEMO 3/ SuperNEMO experiments 8

  9. bb2n measurement bb0n search Multi source detector 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 Detector bkg measurement natTe893 g 100Mo6.914 kg Qbb = 3034 keV 82Se0.932 kg Qbb = 2995 keV Cu621 g 28 July 2007, SUSY07, Karlsruhe Vladimir Vasiliev NEMO 3/ SuperNEMO experiments 9

  10. Sector interior view cathode rings wire chamber PMTs Calibration tube scintillators bb isotope foils 28 July 2007, SUSY07, Karlsruhe Vladimir Vasiliev NEMO 3/ SuperNEMO experiments 10

  11. Installation in Modane 28 July 2007, SUSY07, Karlsruhe Vladimir Vasiliev NEMO 3/ SuperNEMO experiments 11

  12. Installation in Modane 28 July 2007, SUSY07, Karlsruhe Vladimir Vasiliev NEMO 3/ SuperNEMO experiments 12

  13. With shielding water tank wood coil iron shield 28 July 2007, SUSY07, Karlsruhe Vladimir Vasiliev NEMO 3/ SuperNEMO experiments 13

  14. Full detector now 28 July 2007, SUSY07, Karlsruhe Vladimir Vasiliev NEMO 3/ SuperNEMO experiments 14

  15. 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 Typical bb2n event observed from 100Mo 100Mo6.914 kg Qbb = 3034 keV Criteria to select bb events: • 2 tracks with charge < 0 • 2 PMT, each > 200 keV • PMT-Track association • Common vertex • Internal hypothesis TOF (external event rejection) • No other isolated PMT (g rejection) • No delayed a track (214Bi rejection) 28 July 2007, SUSY07, Karlsruhe Vladimir Vasiliev NEMO 3/ SuperNEMO experiments 15

  16. External double Compton Compton + Moller pair production Internal b- +Compton b- +Moller b- +IC NEMO backgrounds • Natural radioactivity: • U/Th chain • 40K • Radon • cosmic m • neutrons 28 July 2007, SUSY07, Karlsruhe Vladimir Vasiliev NEMO 3/ SuperNEMO experiments 16

  17. Backgrounds: bb-like events from Cu - background sources simulated using Monte Carlo - radioactivity rates from material tests in HPGe and control channel meas's Phase II data; 1.5 y x 0.6 kg ~ 1 kg y. MC prediction: 130 ev. 28 July 2007, SUSY07, Karlsruhe Vladimir Vasiliev NEMO 3/ SuperNEMO experiments 17

  18. Angular distribution Sum energy spectrum 12000 10000 8000 6000 4000 2000 0 219 000 events 6914 g 389 days S/B = 40 219 000 events 6914 g 389 days S/B = 40 12000 10000 8000 6000 4000 2000 0 Number of events • Data 22 Monte Carlo • Data 22 Monte Carlo Background subtracted Background subtracted Cos() T1/2() = 7.11  0.02 (stat)  0.54 (syst)  1018 years « factory»→ tool for precision test NEMO 3 highlights: 2b2n100Mo NEMO-3 NEMO-3 100Mo 100Mo Number of events/0.05 MeV E1 + E2 (MeV) Phys. Rev. Lett. 95 182302 (2005) 28 July 2007, SUSY07, Karlsruhe Vladimir Vasiliev NEMO 3/ SuperNEMO experiments 18

  19. 48Ca NEMO 3 highlights: 2b2n preliminary Preliminary results for ~360 d Phase I data. Additional statistics is being analysed and to be published soon. 82Se T1/2 = 9.6 ± 0.3 (stat) ± 1.0 (syst)  1019 y 116Cd T1/2 = 2.8 ± 0.1 (stat) ± 0.3 (syst)  1019 y 150Nd T1/2 = 9.7 ± 0.7 (stat) ± 1.0 (syst)  1018 y 96Zr T1/2 = 2.0 ± 0.3 (stat) ± 0.2 (syst)  1019 y 48Ca T1/2 = 3.9 ± 0.7 (stat) ± 0.6 (syst)  1019 y 932 g 389 days 2750 events S/B = 4 82Se Important ingridient for M0n calculation in QRPA 28 July 2007, SUSY07, Karlsruhe Vladimir Vasiliev NEMO 3/ SuperNEMO experiments 19

  20. NEW in 2007: direct meas. of 130Te 2b2n • The  half-life of 130Te has been a long-standing mystery:: • Geochemical: • (25 ± 2) x 1020 years (Kirsten 83) • (27 ± 2) x 1020 years (Bernatowicz 93) • (7.9 ± 1) x 1020 years (Takaoka 96) • ~8 x 1020 years (Manuel 91) • Difference between ‘old’ and ‘young’ ores due to • time dependence of constants..? • Ratio of 82Se/130Te (less systematic): • (9 ± 1) x 1020 years (average by A. Barabash) • Direct measurement: • (6.1 ± 1.4 (syst) ± 2.93.4(stat)) x 1020 years (Arnaboldi 2003) 28 July 2007, SUSY07, Karlsruhe Vladimir Vasiliev NEMO 3/ SuperNEMO experiments 20

  21. NEW in 2007: direct meas. of 130Te 2b2n 109 events 607 events background subtracted 534 days, 454 g of 130Te 28 July 2007, SUSY07, Karlsruhe Vladimir Vasiliev NEMO 3/ SuperNEMO experiments 21

  22. NEMO 3 highlights: 2b0n100Mo & 82Se 100Mo, Phase I + II, 693 days 82Se ,Phase I + II, 693 days T1/2 > 2.1 x 1023 (90 % CL) <mn>* < 1.4-2.2 eV l'111 < 2.5 10-4 T1/2 > 5.8 x 1023 (90 % CL) <mn>* < 0.8 – 1.3 eV l'111 < 1.5 10-4 T1/2 > 8 x 1023 (90 % CL) <mn>* < 0.7-1.1 eV expected in 2009: T1/2 > 2 x 1024 (90 % CL) <mn>* < 0.4 – 0.7 eV • Collaboration decided to perform blind analysis with mock data • Plan to open the box and update the results ~ summer 2008 and again ~ early 2010. * Recent QRPA NME calculation as in MEDEX'07 28 July 2007, SUSY07, Karlsruhe Vladimir Vasiliev NEMO 3/ SuperNEMO experiments 22

  23. 'Majoron' search Lepton number violation due to local symmetry breaking Axions  (‘Majorons’) with coupling to neutrinos best limits n: spectral index, limits on half-life in years ** PI data, R.Arnold et al. Nucl. Phys. A765 (2006) 483 28 July 2007, SUSY07, Karlsruhe Vladimir Vasiliev NEMO 3/ SuperNEMO experiments 23

  24. SuperNEMO project 28 July 2007, SUSY07, Karlsruhe Vladimir Vasiliev NEMO 3/ SuperNEMO experiments 24

  25. SuperNEMO NEMO-3 150Nd or 82Se isotope 100Mo isotope massM 100-200 kg 7 kg 208Tl < Bq/kg if 82Se: 214Bi < 10 Bq/kg 208Tl: < 20 Bq/kg 214Bi: < 300 Bq/kg internal contaminations 208Tl and 214Bi in the foil energy resolution (FWHM) 8% @ 3MeV 4%@ 3 MeV T1/2() > 2 x 1024 y <mn> < 0.4 – 0.7 eV T1/2() > 2 x 1026 y <mn> < 40 – 70 meV From NEMO-3 to SuperNEMO M Tobs NA T1/2 () > ln 2   A N90% CL efficiency  ~ 30 % 8 % 28 July 2007, SUSY07, Karlsruhe Vladimir Vasiliev NEMO 3/ SuperNEMO experiments 25

  26. 1 module: Source (~40 mg/cm2) 4 (length) x 3(height) m2 Tracking : drift chamber ~3000 cells in Geiger mode Calorimeter: scintillators + PM ~1 000 PM if scint. blocks ~ 100 PM if scint. bars Very preliminary SuperNEMO design Planar and modular design: ~ 100 kg of isotope (~20 modules  5-7 kg) 4 m Top view 1 m 5 m 5 m 28 July 2007, SUSY07, Karlsruhe Vladimir Vasiliev NEMO 3/ SuperNEMO experiments 26

  27. R&D: SuperNEMO calorimeter • Goal: FWHM  7%/E  4% at 3 MeV (Currently 14-16%/E in NEMO3) • A combination of energy losses in the foil and calorimeter DE/E • Studies • Organic (plastic or liquid), • Shape, size, coating • PMTs (Photonis, Hamamatsu, ETL) • Light guides, optical contact • Chemistry High QE Hamamatsu tube = DE/E = 6.5% at 1 MeV  3.8% at 3 MeV if 1/E + BC404 scintillator wraped in teflon 28 July 2007, SUSY07, Karlsruhe Vladimir Vasiliev NEMO 3/ SuperNEMO experiments 27

  28. Qbb (MeV) Isotopic Abundance R&D: isotope enrichment/ purification Choice of nucleus depends on: • enrichment possibilities • high Q value  larger phase space  lower non- background • small 2 contribution • 4 kg of 82Se funded by ILIAS • have been delivered from Russia. • purification at ILN (US) underway • enrichment of Nd possible in France (MENPHIS, currently mothballed) Two main options: G0(150Nd) / G0(82Se) = 8 28 July 2007, SUSY07, Karlsruhe Vladimir Vasiliev NEMO 3/ SuperNEMO experiments 28

  29. 2010 2011 2007 2008 2009 2012 2013 NEMO3 Running TDR R&D SuperNEMO BiPo construction SuperNEMO 1st module construction construction of 20 modules RUNNING of Full detector SuperNEMO schedule summary BiPo1 Canfranc BiPo installation BiPo running @ Canfranc Preparation of the site 6 SuperNEMO modules running @ Canfranc Final SuperNEMO modules installation 28 July 2007, SUSY07, Karlsruhe Vladimir Vasiliev NEMO 3/ SuperNEMO experiments 29

  30. Conclusion NEMO’s Tracking+Calorimetry approach is unique: -high background rejection - choice of isotopes - reconstruction of kinematics NEMO 3 is taking data: - factory, important for understanding of backgrounds and NME -limits on  using different isotopes: -T1/2 (> 5.8 x 1023 y @ 90% CL for 100Mo  <m> < 0.8-1.3 eV (693 days); l'111 < 1.5 x 10-4 -limits on Majoron's coupling -T 1/2() = (7.6 ± 1.5 (stat) ± 0.8(syst)) x 1020 y for 130Te SuperNEMO R&D approved in France, the UK and Spain; TDR expected in 2008; full 20 modules in 2012-2013 -choice of isotopes: 82Se or 150Nd 28 July 2007, SUSY07, Karlsruhe Vladimir Vasiliev NEMO 3/ SuperNEMO experiments 30

  31. Backup slides 28 July 2007, SUSY07, Karlsruhe Vladimir Vasiliev NEMO 3/ SuperNEMO experiments 31

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