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Status of NEMO 3/ SuperNEMO experiments. Vladimir Vasiliev UCL, London, UK on behalf of the NEMO collaboration. Physics of Massive Neutrinos Joint Annual Meeting of N4 IDEA and N6/WP1 ENTApP Blaubeuren, 1-5 July 2007. Outline. NEMO-3 experiment Overview of the NEMO-3 NEMO-3 background
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Status of NEMO 3/ SuperNEMO experiments Vladimir Vasiliev UCL, London, UK on behalf of the NEMO collaboration Physics of Massive Neutrinos Joint Annual Meeting of N4 IDEA and N6/WP1 ENTApP Blaubeuren, 1-5 July 2007
Outline • NEMO-3 experiment • Overview of the NEMO-3 • NEMO-3 background • Highlights of the main NEMO-3 results • SuperNEMO project • Challenges and R&D program • Current status 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 2
NEMO 3: Neutrino Ettore Majorana Observatory • Czech Republic • Finland • France • Japan • Russia • Spain • UK • Ukraine • USA LS Modane, FR Tunnel Frejus 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 3
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 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 4
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 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 5
Sector interior view cathode rings wire chamber PMTs Calibration tube scintillators bb isotope foils 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 6
Installation in Modane 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 7
Installation in Modane 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 8
With shielding water tank wood coil iron shield 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 9
Full detector now 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 10
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) 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 11
External double Compton Compton + Moller pair production Internal b- +Compton b- +Moller b- +IC NEMO backgrounds 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 12
Backgrounds: external g 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 13
Backgrounds : internal from b- decay single electron events 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 14
(164 ms) b a Backgrounds: Radon, delayed 214Po a Bi-Po Process 238U 214Po 214Bi (19.9 mn) 210Pb 22.3 y 0.021% 210Tl (1.3 mn) • a track length & event topology allows to separate 214Bi on • surface of GG wires • tracking gas • surface of the foil • inside the source foil 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 15
Backgrounds: Radon purification facility Running since Oct. 4th, 2004 in FréjusUnderground Lab. 1 ton charcoal @ -50oC, 7 bars Flux: 150 m3/h Activity of 222Rn : Before Facility = 15 Bq/m3 After Facility < 15 mBq/m3 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 16
Radon purification facility, effect inside NEMO3 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 17
Backgrounds: bb-like events from Cu Phase II data; ~ 1.5 y. MC prediction: 130 ev. 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 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 22 Monte Carlo • Data 22 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) 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 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 Background subtracted 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 20
NEMO 3 highlights: 2b0n100Mo & 82Se 100Mo, Phase I + II, 693 days 82Se ,Phase I + II, 693 days T1/2 > 5.8 x 1023 (90 % CL) <mn> < 0.6 – 1.2 eV T1/2 > 2.1 x 1023 (90 % CL) <mn> < 1.2-2.3 eV expected in 2009: T1/2 > 2 x 1024 (90 % CL) <mn> < 0.3 – 0.65 eV T1/2 > 8 x 1023 (90 % CL) <mn> < 0.6-1.2 eV • Collaboration decided to perform blind analysis with mock data • Plan to open the box and update the results ~ summer 2008 • and once again @ the end of the experiment ~ early 2010. 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 21
SuperNEMO project 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 22
~ 60 physicists, 27 laboratories, 12 countries, Japan U Saga KEK U Osaka Marocco Fes U USA MHC INL (U Texas) Russia JINR Dubna ITEP Mosow Kurchatov Institute UK UC London 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 Zaragoza U Barcelona Czech Republic Charles U Praha IEAP Praha 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 23
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 T1/2() > 2 x 1026 y From NEMO-3 to SuperNEMO M Tobs NA T1/2 () > ln 2 A N90% CL efficiency ~ 30 % 8 % 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 24
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 Conceptual SuperNEMO design Planar and modular design: ~ 100 kg of isotope (~20 modules 5-7 kg) 4 m Top view 1 m 5 m 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 25
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 See Jean-Stephane's talk for details 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 26
R&D: tracker optimisation • optimize: • wire length and diameter • wire material and diameter, • read-out, gas mixture etc • 9-cell prototype built • 90 cell prototype + 300 cell prototype to be built by Spring 2008 • About 500k wires to be strung, crimped, terminated => wire robot under development 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 27
e- prompt e- Bi-Po Process 238U 214Po (164 ms) b 214Bi (19.9 mn) a 210Pb 22.3 y Scintillator + PMT 0.021% 210Tl (1.3 mn) Tracking (wire chamber) 232Th Source foil (40 mg/cm2) 212Po (300 ns) b 212Bi (60.5 mn) Shield radon, neutron,g a 208Pb (stable) 36% e- a delay 208Tl (3.1 mn) R&D : radio purity and BiPo device • Need to measure radio purity at a few mBq/kg level • Beyond sensitivity of conventional Ge detectors • Build new tool, BiPo detector. a Delay a See Xavier's talk for more details 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 28
R&D: 82Se production and purification • Gaseous compound exist (SeF6) • can enrich with ultracentrifugation! • Test sample of few kilograms has been produced • purity of the production under investigation on Ge detector • several purification methods proposed • chemical purification • distillation, physical purification 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 29
R&D: 150Nd production at CEA-MENPHIS No gaseous compuond! need alternative technology. Laser-vapor interaction SILVA / AVLIS (Atomic Vapor Laser Ionization S) • 1973 : Atomic isotope separation by laser : initial patent • 1980 : Basic research at CEA (spectroscopy, evaporation) • 1985 : SILVA/AVLIS selected as advanced process : • USA, France, Japan • 1994 : Tens of grams produced at the industrial assay • 1994-1998 : Technological demonstrations (by parts) • Mid 1999 : AVLIS shut down in US ; early 2003 in Japan • 2000: Decision for a conclusive 4 years program • 2000 - 2003: MENPHIS construction and preliminary R&D. • 2003 : Demonstrations on MENPHIS • 204 kg @ 2.5% 235U 2 Isotopes 235U and 238U 5 energy levels (3 transitions) 3 • Current status: mothbolled • 150Nd is possible, but: • Cost? • Enrichement? • Purity? 2 1 235U 238U Photoionization 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 30
R&D: physics simulations • Full MC simulation under development • GEANT4 for low energy physics simulation • Use NEMO-3 & prototype data for accurate tracking chamber simulation • Simulate light transmission for accurate calorimeter simulation • DECAY-4 library for decay kinematics (bb and all radioactive backgrounds) • Cellular automate + Kalman filter for track fit • Will be used to provide input for TDR Preliminary! 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 31
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 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 32
neutrino mass limits comparison QRPA SU(3) Shell model * Deformation of 150Nd nucleus is not taken into account NME calculatios from the following works: [1] O. Civatarese and J. Suhonen, Nucl. Phys. A 729 (2003) 867 (Table 4) [2] S. Stoica and H. Klapdor-Kleingrothaus, Nucl. Phys. A 694 (2001) 269 [3] V.A. Rodin et al., Nucl. Phys. A 766 (2006) 107 (nucl-th/0503063) +erratum (Table 1)[4] E. Caurier, F. Nowacki, A. Poves and J. Retamosa, Nucl. Phys. A654 (1999) 973c (Shell model calculation) [5] H.G. Hirsch, O. Castanos, P.O. Hess, Nucl. Phys A582 (1995) 124 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 33
Conclusion • NEMO 3 will continue to take data for few years more • detector background at low energies (2n) understood • analysis of ~ 3y of 2b2n data for all isotopes in progress and to be published soon • update of 2b0n results ~ next summer • SuperNEMO is undergoing R&D stage • extensive TDR report to be submitted in 2009 to funding agencies 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 34
Backup slides 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 35
Magnetic field: 25 Gauss Gamma shield: Pure Iron (18 cm) Neutron shield: borated water + Wood NEMO 3: details Fréjus Underground Laboratory : 4800 m.w.e. • Source: 10 kg of isotopes • cylindrical, S = 20 m2, 60 mg/cm2 • Tracking detector:drift wire chamber operating in Geiger mode (6180 cells) • ┴ = 5 mm, z = 1 cm ( vertex ) • Calorimeter: 1940 plastic scintillators coupled to low radioactivity PMTs • Energy Resolution FWHM=14% (1 MeV) • Time resolution = 0.25 ns @ 1MeV • g veto efficiency ≈ 50 % Background:natural radioactivity, mainly 214Bi and 208Tl (g 2.6 MeV) Radon, neutrons (n,g), muons, bb(2n) 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 36
exotic processes search in 100Mo & 82Se • Neutrino coupled axions c (majorons) • V+A current in electroweak lagrangian *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 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 37
Challenges & R&D program • Radio purity • source isotope purification • new tools for extra low radioactivity measurement (BiPo) • Better calorimeter resolution • R&D on individual counter design • calibration system R&D • Bigger scale • optimise tracker parameters • wiring robot • Detector efficiency • source thickness • geometry optimisation • reconstruction software • Better background rejection • 150Nd • extra veto counters • alternative, "sandwich", layout 1-5 July 2007, ILIAS meeting, Blaubeuren Vladimir Vasiliev NEMO 3/ SuperNEMO status 38