Double beta decay with NEMO3 and SuperNEMO

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Outline 0νββ and 2νββ Observation technique Nemo-3 Results SuperNEMO design and construction. Double beta decay with NEMO3 and SuperNEMO. Stefano Torre University College London for NEMO3 and SuperNEMO collaborations Half day IoP Meeting 12 Oct 2011. - PowerPoint PPT Presentation

Transcript of Double beta decay with NEMO3 and SuperNEMO

  • Stefano TorreUniversity College London

    for NEMO3 and SuperNEMO collaborations

    Half day IoP Meeting12 Oct 2011Double beta decay with NEMO3 and SuperNEMO

  • *S.Torre - Double beta decays with NEMO3 and SuperNEMO - 12/10/2011Which process cause the double beta decay?But can be due to mass mechanism, V+A, majoron, SUSY, ... with different topology in the final state - angle between e1 and e2E1 - single e- energy, keVmV+A

  • *S.Torre - Double beta decays with NEMO3 and SuperNEMO - 12/10/2011Measuring the Lepton Violating parameterPhase space factor

    IsotopeQ, MeV48Ca4.2776Ge2.0482Se3.096Zr3.35100Mo3.03116Cd2.8130Te2.53136Xe2.48150Nd3.37G010-15 yr-175.87.633,569.754.558.952.856.3249

  • *S.Torre - Double beta decays with NEMO3 and SuperNEMO - 12/10/2011NEMO3 isotope foilsPMTcathode rings wire chamberPlasticscintillatoruse calorimeter for energy and time measurementuse tracker for full event reconstructionidentify e-, e+, , 10 kg of isotopes: 7kg 100Mo 1kg 82Sesmaller quantities of 116Cd, 150Nd, 48Ca, 96Zr, 130Te

  • *S.Torre - Double beta decays with NEMO3 and SuperNEMO - 12/10/2011NEMO3source distributed on cylindrical surfacedrift wire chamber operated in geiger mode (6180 cells)He + 4% ethyl alcohol + 1% Ar + 0.1%H2Ocalorimeter made of 1940 plastic scintillators coupled to low radioactivity PMTsMagnetic field: 25 GaussGamma shield: ironNeutron shield:30cm borated water (external wall)40cm wood (top and bottom)

  • *S.Torre - Double beta decays with NEMO3 and SuperNEMO - 12/10/2011NEMO3LSM Modane, France(Tunnel Frejus, depth of ~4,800 mwe )

  • *Selection of eventsS.Torre - Double beta decays with NEMO3 and SuperNEMO - 12/10/2011

  • *S.Torre - Double beta decays with NEMO3 and SuperNEMO - 12/10/2011BackgroundsBackground measurement in NEMO-3: NIM A606 (2009) 449 Natural radioactivity238U, 232Th, 40K, Rn

    Cosmics

    neutrons

  • *S.Torre - Double beta decays with NEMO3 and SuperNEMO - 12/10/2011Background: Rn activityT1/2 = 162.9sDelay time of the track (s)

  • *S.Torre - Double beta decays with NEMO3 and SuperNEMO - 12/10/2011700000 two-electron events from 100Mo foilsS/B = 76 (22) = 0.043 T1/2(22) = [7.16 + 0.01 (stat)] 1018 y PRELIMINARY

    To be compared with the published NEMO-3 result obtained with Phase 1 data T1/2 = [7.11 + 0.02(stat) + 0.54(syst)] 1018 y Phys.Rev.Lett. 95(2005)483100Mo100Mo100Mo100Mo220000 evtsS/B=40Phase 1NEMO-32 100Mo Phase 2 data, 4 years

  • *S.Torre - Double beta decays with NEMO3 and SuperNEMO - 12/10/20112 ResultsFirst direct observation

    Indirect observations:- ~2.7 x 1021 yrs in 109 yr old rocks- ~8 x1020 yrs in 107-108 yr old rocks

    Indication from MIBETA Coll in isotopically enriched crystals: 6.1 1.4(st) +2.9-3.5(sy) x1020 yrs

    IsotopeMass (g)Q(keV)T1/2(2) (1019yrs)CommentReference82Se93229969.6 1.0Worlds best!116Cd7.4928092.8 0.3Worlds best!150Nd3733670.9 0.07Worlds best!Phys. Rev. C 80, 032501 (2009)96Zr9.433502.35 0.21Worlds first and best!Nucl.Phys.A 847(2010)16848Ca742714.4 0.6Worlds best!100Mo691430340.71 0.05Worlds best!Phys.Rev.Lett. 95(2005)483130Te454253370 14Worlds first and best!Phys. Rev. Lett. 107, 062504 (2011)

  • *Search for 0S.Torre - Double beta decays with NEMO3 and SuperNEMO - 12/10/2011[1] QRPA M.Kortelainen and J.Suhonen, Phys.Rev. C 75 (2007) 051303(R)[2] QRPA M.Kortelainen and J.Suhonen, Phys.Rev. C 76 (2007) 024315[3] QRPA F.Simkovic, et al. Phys.Rev. C 77 (2008) 045503 PHFB [5] P.K. Rath et al., Phys. Rev. C 82 (2010) 064310[4] IBM2 J.Barrea and F.Iachello Phys.Rev.C 79(2009)044301 SM [6] E.Caurrier et al. Phys.Rev.Lett 100 (2008) 052503NME82Se100Mo100Mo : 7kg 4.5 years82Se : 1kg 4.5 years

  • *S.Torre - Double beta decays with NEMO3 and SuperNEMO - 12/10/2011n: spectral index, limits on half-life in years* Phase I+Phase II data (including 2008)** Phase I data, R.Arnold et al. Nucl. Phys. A765 (2006) 483Majoron emission would distort the shape of the energy sum spectrumPreliminary

    V+A*n=1n=2**n=3**n=7**Mo>5.71023 5.31022 Gee1.71022 >1.01022>71019Se>2.41023 1.51022 **Gee61021>3.11021>51020

  • *S.Torre - Double beta decays with NEMO3 and SuperNEMO - 12/10/201112th January 2011: So long NEMO3

  • *S.Torre - Double beta decays with NEMO3 and SuperNEMO - 12/10/2011From NEMO to SuperNEMO Isotope mass MIsotope Contaminations in the foil Calorimeter energy resolution (FWHM) 7 kg 100Mo NEMO-3208Tl: ~ 100 Bq/kg214Bi: < 300 Bq/kgRn: 5 mBq/m3 T1/2(0) > 12 x 1024 y < 0.3 0.9 eV8% @ 3MeV100+ kg 82Se (or 150Nd or 48Ca) SuperNEMO208Tl 2 Bq/kg214Bi 10 Bq/kgRn 0.15 mBq/m3T1/2(0) > 1 x 1026 y < 0.04 - 0.1 eV4% @ 3 MeVRn in the trackerSensitivityR&D since 2006

  • *S.Torre - Double beta decays with NEMO3 and SuperNEMO - 12/10/2011SuperNEMOModular design20 modules, each with 5kg of isotope

    Each Module:Source: (40mg/cm2) 4x2.7m282Se (High Q, long T1/2(2), proven enrichment technology)150Nd, 48Ca being looked atTrackingdrift chamber ~2000 cells in Geiger modeCalorimeter: 550 PMTs + scintillatorsModule surrounded by water and passive shielding

  • *S.Torre - Double beta decays with NEMO3 and SuperNEMO - 12/10/2011Main calorimeter walls designRequired resolution has now been reached on hexagonal as well as cubic blocks

  • *S.Torre - Double beta decays with NEMO3 and SuperNEMO - 12/10/2011X-walls R&D and constructionUse scintillators on the side of tracker (X-wall) for event reconstructionincrease acceptance on signal and SuperNEMO sensitivity if resolution
  • *S.Torre - Double beta decays with NEMO3 and SuperNEMO - 12/10/2011Tracker R&D Basic design developed and verified with several prototypesResolution: 0.7mm transverse, 1cm longitudinalCell efficiency > 98%Automated wiring robot design to mass produce at ultra low background conditionReadout electronic being developed right now:Allow for single and double cathodes readoutDifferentiate anode signal

  • S.Torre - Double beta decays with NEMO3 and SuperNEMO - 12/10/201182Se source radiopurityshaped in foils of 40-50 mg/cm2radio purity 208Tl < 2 Bq/kg 214Bi < 10 Bq/kgdedicated BiPo detector developed and installed in Canfranc

  • *Radon Detector(Electrostatic & Pin Diode)S.Torre - Double beta decays with NEMO3 and SuperNEMO - 12/10/2011Rn activity measurementVacuum PumpCarbon TrapRadon Concentration Linesensitivity < 0.1 mBq/m3

  • *S.Torre - Double beta decays with NEMO3 and SuperNEMO - 12/10/2011The Demonstratorof the technologyof the control of background levelsless than 0.2 background events in 2.76 - 3 MeV with 21 kg yr (7kg3yrs)to produce competitive result:reach NEMO3 (100Mo) sensitivity in 4.5 monthsreach Gerda-I sensitivity by 2015if good it will be the first SuperNEMO module

  • *S.Torre - Double beta decays with NEMO3 and SuperNEMO - 12/10/2011ScheduleInstallation in LSMDemonstrator Module construction and commissioningDemonstrator Module running. Klapdor sensitivity end of 2015 Construction and deployment of successive SuperNEMO modules Continuous operation of 1 SuperNEMO module

  • *S.Torre - Double beta decays with NEMO3 and SuperNEMO - 12/10/2011ConclusionsNEMO3 has finished data takingno evidence of lepton violating decays has been foundthe double beta decay of seven isotopes has been measuredanalysis of final samples is currently ongoing

    SuperNEMO design is now being finalized

    the Demonstrator has now entered the construction phase

  • *S.Torre - Double beta decays with NEMO3 and SuperNEMO - 12/10/2011Backup

  • *S.Torre - Double beta decays with NEMO3 and SuperNEMO - 12/10/2011Th and U chains

  • *S.Torre - Double beta decays with NEMO3 and SuperNEMO - 12/10/2011[2.8,3.2]MeV in 4.5 years 18 events observed, 16.4+1.3 expectedSearch for 0 with 100Mo

  • *S.Torre - Double beta decays with NEMO3 and SuperNEMO - 12/10/2011[2.6,3.2]MeV in 4.5 years 14 events observed, 11.1+1.3 expectedSearch for 0 with 82Se

  • *S.Torre - Double beta decays with NEMO3 and SuperNEMO - 12/10/2011[9.60.1(stat)1.0(sys)]1019 y[9.11+0.25-0.22(stat)0.63(sys)]1018 yPhys. Rev. C 80, 032501 (2009)[2.350.14(stat)0.16(sys)]1019 yNucl.Phys.A 847(2010)168[2.880.04(stat)0.16(sys)]1019 y[4.4+0.5-0.4(stat)0.4(sys)]1019 y82Se130Te116Cd96Zr150NdPreliminaryPreliminary[7.00.9(stat)1.1(sys)]1020 yPhys. Rev. Lett. 107, 062504 (2011)2 Results