Prsentation PowerPoint

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NEMO-3 Experiment Neutrino Ettore Majorana
Observatory RESULTS OF NEMO3 SUPERNEMO
Laurent Simard 1 for the NEMO-3
Collaboration CENBG, IN2P3-CNRS et Université de
Bordeaux, France Charles University, Praha, Czech
Republic CTU, Praha, Czech Republic FES
University, Morocco INEEL, Idaho Falls, USA IReS,
IN2P3-CNRS et Université de Strasbourg,
France ITEP, Moscou, Russia JINR, Dubna, Russia
Jyvaskyla University, Finland Kharkov
University, Ukrain 1 LAL, IN2P3-CNRS et
Université Paris-Sud, France LSCE, CNRS Gif sur
Yvette, France LPC, IN2P3-CNRS et Université de
Caen, France Manchester University, United
Kingdom Mount Holyoke College, USA University of
Osaka, Japan RRC Kurchatov Institute, Moscow,
Russia Saga University, Saga, Japan University of
Texas, USA UCL, London, United Kingdom
Laurent Simard for the NEMO-3 Collaboration
WIN 05 Delphi 06-11 June 2005
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• Plan of the talk
• Results of NEMO-3 experiment
• NEMO-3 Detector
• Measurement of bb2n decay for several nuclei
• Search for bb0n decay with 100Mo and 82Se
• Description of future projects
• The SUPERNEMO project
• other projects

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The NEMO3 detector
Fréjus Underground Laboratory 4800 m.w.e.
Source 10 kg of ?? isotopes cylindrical, S
20 m2, e 60 mg/cm2 Tracking detector
drift wire chamber operating in Geiger
mode (6180 cells) Gas He 4 ethyl alcohol 1
Ar 0.1 H2O Calorimeter 1940
plastic scintillators coupled to low
radioactivity PMTs
Laurent Simard for the NEMO-3 Collaboration

WIN 05 Delphi 06-11 June 2005
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Cathodic rings Wire chamber
PMTs
Calibration tube
scintillators
bb isotope foils
Laurent Simard for the NEMO-3 Collaboration
WIN 05 Delphi 06-11 June 2005
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AUGUST 2001
Laurent Simard for the NEMO-3 Collaboration
WIN 05 Delphi 06-11 June 2005
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NEMO-3 Opening Day, July 2002 Start taking data
14 February 2003
Water tank
wood
coil
Iron shield
Laurent Simard for the NEMO-3 Collaboration
WIN 05 Delphi 06-11 June 2005
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bb decay isotopes in NEMO-3 detector
116Cd 405 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
130Te 454 g Qbb 2529 keV
External bkg measurement
100Mo 6.914 kg Qbb 3034 keV
82Se 0.932 kg Qbb 2995 keV
natTe 491 g
Cu 621 g
(All the enriched isotopes produced in Russia)
Laurent Simard for the NEMO-3 Collaboration
WIN 05 Delphi 06-11 June 2005
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bb events selection in NEMO-3
Typical bb2n event observed from 100Mo
Transverse view
Run Number 2040 Event Number 9732 Date
2003-03-20
Longitudinal view
100Mo foil
100Mo foil
Geiger plasma longitudinal propagation
Scintillator PMT
Laurent Simard for the NEMO-3 Collaboration
WIN 05 Delphi 06-11 June 2005
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2e- event
e-N??event?to measure ?????l ?
? - ? (delay track) event 214Bi ? 214Po ?
210Pb
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Performance of the detector
Laurent Simard for the NEMO-3 Collaboration
WIN 05 Delphi 06-11 June 2005
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Measurement of 2b2n decay in NEMO-3
Laurent Simard for the NEMO-3 Collaboration
WIN 05 Delphi 06-11 June 2005
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100Mo 2?2? preliminary results
(Data 14 Feb. 2003 22 Sep. 2004)
Sum Energy Spectrum
Angular Distribution
219 000 events, S/B 40 6914 g, 389 days
219 000 events 6914 g 389 days S/B 40
NEMO-3
NEMO-3
100Mo
100Mo

• Data

2?2? Monte Carlo

• Data

Background subtracted
2?2? Monte Carlo
Background subtracted
7.37 kg.y
T1/2 7.11 0.02 (stat) 0.54 (syst) ? 1018 y
Laurent Simard for the NEMO-3 Collaboration
WIN 05 Delphi 06-11 June 2005
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2?2? preliminary results for other nuclei
NEMO-3
Background subtracted
932 g 241.5 days 2385 events S/B 3.3
82Se
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
NEMO-3
NEMO-3
NEMO-3
37 g 168.4 days 449 events S/B 2.8
5.3 g 168.4 days 72 events S/B 0.9
405 g 168.4 days 1371 events S/B 7.5
96Zr
150Nd
116Cd
bb2n simulation
bb2n simulation
bb2n simulation
E1E2 (MeV)
E1E2 (MeV)
E1E2 (MeV)
Laurent Simard for the NEMO-3 Collaboration
WIN 05 Delphi 06-11
June 2005
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Search for 2b0n decay in NEMO-3
Laurent Simard for the NEMO-3 Collaboration
WIN 05 Delphi 06-11 June 2005
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bb0n Analysis Background Measurement
NEMO-3 can measure each component of its
background !

• External Background 208Tl (PMTs)
• Measured with (e-, g) external events
• 10-3 bb0n-like events year-1 kg -1 with 2.8ltE1
  E2lt3.2 MeV

• External Neutrons and High Energy gamma
• Measured with crossing e- or (e-,e)int events
  with E1E2 gt 4 MeV
• ? 0.05 bb0n-like events year-1 kg -1 with 2.8ltE1
  E2lt3.2 MeV

• 208Tl impurities inside the foils 60 mBq/kg
• Measured with (e-,2g), (e-,3g) events coming
  from the foil
• 0.06 bb0n-like events year-1 kg -1 with 2.8ltE1
  E2lt3.2 MeV

• Radon inside NEMO-3 detector
• Measured with (e-,g,a) events from the gas or the
  foil
• 1 bb0n-like events year-1 kg -1 with 2.8ltE1
  E2lt3.2 MeV

• 100Mo bb2n decay T1/2 7.14 1018 y
• 0.3 bb0n-like events year-1 kg -1 with
  2.8ltE1E2lt3.2 MeV

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Limit on the effective mass of the Majorana
neutrino Phase 1 (Feb. 2003 Sept. 2004 1.08 y
of data) with radon bkg (limits _at_ 90 CL)
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Limit on Majoron and on VA (limits _at_ 90 CL)

Limit on Majoron 100Mo
T1/2 (bb0nM) gt 1.8 1022 y
82Se T1/2 (bb0nM) gt 1.5 1022
y gM lt (5.3 8.5) 10-5
(best limit)
gM lt (0.7 1.6) 10-4
Simkovic (1999), Stoica (1999)

Simkovic (1999), Stoica (2001)

• 
  Limit on VA
• 100Mo T1/2 (bb0n VA) gt 2.3 1023 y
  82Se T1/2 (bb0n VA)
  gt 1.0 1023 y
• l lt (1.5 2.0) 10-6
  
  l lt 3.2 10-6
• Tomoda (1991),
  Suhonen (1994)
  
  Tomoda (1991)

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Free-Radon Purification System in construction
Radon was the dominant background for NEMO-3
Today A(222Rn) in the LSM 15 Bq/m3
Factor 10 too high
May 2004 Tent surrounding the detector
May 2004
August 2004 Radon-free SuperKamiokande-like
Air Factory Expected activity A(222Rn) 0.2
Bq/m3 150 m3/h 2 x 450 kg charcoal _at_ -40oC
Expected Purification Factor 75
Laurent Simard for the NEMO-3 Collaboration
WIN 05 Delphi 06-11 June 2005
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Radon-free air factory
Starts running on October 2004 the 4th In
Laboratoire Souterrain de Modane 2 x 450 kg
charcoal _at_ -50oC, 7 bars Activity A(222Rn) lt 1
mBq/m3 !!! Flux 125 m3/h
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After installation of radon-free air factory
(active charcoal)
222Rn Activity between february 2003 and
september 2004 0.95 Bq
now 0.1 Bq (réduction by a factor 10)
Only 0.7 evt/y of background for bb0n of 100Mo lt
Nbdf due to bb2n
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NEMO-3 Expected sensitivity

• Background
• External Background negligible
• Internal Background 208Tl 60 ?Bq/kg for
  100Mo
• 300
  ?Bq/kg for 82Se
• 214Bi lt 300 ?Bq/kg
  
• 0.1 count kg?1 y ?1 with
  2.8ltE1E2lt3.2 MeV
• ???? 100Mo T1/2 7.14 1018 y
• 0.3 count kg?1 y ?1 with
  2.8ltE1E2lt3.2 MeV

Nuclear Matrice Elements Ref Simkovic (1999),
Stoica (2001), Suhonen (1998,2003), Rodin (2005),
Caurier (1996)
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CONCLUSIONS ON NEMO3

• NEMO-3 Detector running since 14 Feb. 2003
• Expected performance of the detector has been
  reached !
• 2b2n preliminary results for 100Mo, 82Se, 96Zr,
  116Cd and 150Nd
• already more than 235 000 2b2n events
  collected
• 100Mo in favour of Single State
  Dominance (SSD)
• 100Mo bb2n decay to excited state has
  been measured with 4 s
• Preliminary T1/2(bb0n) limit (1.08 years of
  data)
• 100Mo (4.10 kg.y) T1/2(bb0n) gt 4.6 1023 y
  ? ?mn? lt 0.7 2.8 eV
• 82Se (0.55 kg.y) T1/2(bb0n) gt 1023 y ?
  ?mn? lt 1.8 4.9 eV
• Level of backgounds as excepted
• Free radon purification system in operation in
  August 2004
• Reduction of the radon level by a factor 10
• Expected sensitivity in 5 years after radon
  purification
• 100Mo T1/2(bb0n) gt 2 .1024 y ltmngt lt
  0.32 1.35 eV

Laurent Simard for the NEMO-3 Collaboration
WIN 05 Delphi 06-11 June 2005
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The SUPERNEMO project
Idea continue with a tracko-calo like detector
with a mass of few 100 kg of 82Se (T 1/2 bb2n
15 times greater than for 100Mo, Q bb around 3
MeV also) 3 years RD program
Laurent Simard for the NEMO-3 Collaboration
WIN 05 Delphi 06-11 June 2005
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From NEMO-3 to SuperNEMO
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SuperNEMO preliminary design
Side view
Plane and Modular Geometry (5 kg of enriched
isotope/module)
1 Module Source (40 mg/cm2) 4 x 3 m2
Tracking volume drift wire chamber in Geiger
mode, 3000 cells Calorimeter scintillators
PMTs (1000 PMTs)
20 modules 100 kg of enriched isotope
60 000 channels for drift chamber
20 000 PMT if scint. block 2
000 PMT if scint. bars
4 m
1 m
5 m
Top view
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Water shield
Need of cavity of 60m x 15m
x15m Possible in Gran Sasso or in
Modane if a new cavity
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sources RD
GOAL A(214Bi) lt 10 mBq/kg A(208Tl) lt 2
mBq/kg
not only enrich and purify sources, but also
measure their radiopurity
2 mBq/kg of 1 kg of sources give 64 decays/year
!!!
sensitivity in 208Tl of High Purity-Germanium
detectors used for the measurement of NEMO3
sources 60 mBq/kg
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calorimetry RD
Goal reach FWHM less than 4 at 3 MeV (for
NEMO-3 8)
6 (source) () 4 (calo) 7 (global)
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Other projects
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Other projects
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Conclusions

• If any bb0n signal seen in any isotope, it will
  HAVE to be observed by a tracko-calo detector  a
  la NEMO  to tag the 2 e- emitted in bb0n decay

• NEMO-3 reached the expected performance and
  nominal background data taking will continue up
  to 2009
• expected sensitivity T1/2(bb0n) gt 2. 1024 with
  7 kg of 100Mo
• T1/2(bb0n) gt 8. 1023 with 1 kg of 82Se

• NEMO technique can be extrapolated to 100 kg

SuperNEMO is a large scale bb0n detector Need an
international collaboration France, Russia, UK,
Tchec., Japan and USA !