results of nemo 3 and status of supernemo

Results of NEMO 3 and status of SuperNEMO

Ladislav VÁLAon behalf of the NEMO 3 and SuperNEMO collaborations

Institute of Experimental and Applied Physics

Czech Technical University in Prague

NOW 2008, 6 – 13 September 2008, Conca Specchiulla, Italy

Brief introduction – decay

NEMO 3 – description and results

SuperNEMO – current status

Summary

Outline

Ladislav Vála, Results of NEMO 3 and status of SuperNEMO, NOW 2008, 9th September 2008

In even-even nuclei where single decay is highly suppressed or forbidden but decay is possible, e.g. 48Ca, 76Ge, 82Se, 96Zr, 100Mo,116Cd, 130Te, 136Xe, 150Nd,…

100Mo0+

21+

01+

41+

0+

100Ru

22+

30

34

ke

V

100Tc1+

Double beta decay

2 = (T1/2)-1 = G2(Q11,Z) |M2|

2

G2 – phase space factor M – nuclear matrix element

Two-neutrino decay (2):(A,Z) →(A,Z+2) + 2 e + 2 e


Neutrinoless decay (0):(A,Z) →(A,Z+2) + 2 e

0 = (T1/2)-1 = G0(Q5,Z) |M0|

2 m2

G0 – phase space factor M – nuclear matrix elementm = | j |Uej

|2 eij mj | – effective neutrino mass

Energy sum of the electrons

Beyond SM L = 2, Majorana neutrinos with mass > 0Can be due to: light neutrino exchange m, right-handed currents, Majorana emission, SUSY particle exchange

Calorimetry plus tracking Detection of both electrons: reject unknown nuclear gamma lines

Three kinematic observables: study underlying physics mechanism

(i) individual electron energies (ii) angular correlation (iii) energy sum

Sources separated fromthe detector: measure T1/2 for several isotopes

Background rejection throughparticle identification: e–, e+, , particles

Unique and complementary

NEMO experimental approach


Modane


Detector located in the LSM Modane underground laboratory, France (4800 m.w.e.)

Source: 10 kg of isotopes, cylindrical, S = 20 m2, foils ~ 60mg/cm2

Tracking detector: drift wire chamber operating in Geiger mode (6180 cells)gas = 94% He + 4% ethyl alcohol + 1% Ar + 0.1% H2O

Calorimeter: 1940 plastic scintillators coupled to low radioactivity PMTs

NEMO 3 detector

NEMO = Neutrino Ettore Majorana Observatory

B (25 G)

4 m

20 sectors

3 m

6 m

6 m

Magnetic field: 25 GaussGamma shield: pure iron (18 cm layer)Neutron shield: borated water (ext. wall, 30 cm layer) & wood (top and bottom, 40 cm layer)

Surrounded by an anti-radon tent supplied with Rn-free air from an anti-radon factory

identification of e–, e+, and -particles

116Cd 405 gQ = 2805 keV

96Zr 9.4 gQ = 3350 keV

150Nd 37.0 gQ = 3367 keV

48Ca 7.0 gQ = 4272 keV

130Te 454 gQ = 2529 keV

natTe 491 g

Cu 621 g

2 decaymeasurement

External background measurement

100Mo 6.914 kgQ = 3034 keV 0 decay search

82Se 0.932 kgQ = 2995 keV

&

NEMO 3 sources

All sources produced by centrifugation in Russia


Deposited energy: E1 + E2= 2088 keVInternal hypothesis: (t)mes – (t)theo = 0.22 nsCommon vertex: (vertex) = 2.1 mm (vertex)// = 5.7 mm

Run Number: 2040Event Number: 9732Date: 2003-03-20

100Mo foils

Scintillator+ PMT

Longitudinal viewTransverse view

Vertex of the ee emission

Vertex of the ee emission

event reconstruction

Criteria to select events:

• 2 tracks with charge < 0• 2 PMTs, each > 200 keV• PMT-Track association • Common vertex

• Internal hypothesis TOF (external event rejection)• No other isolated PMT ( rejection)• No delayed track (214Bi rejection)


Results for 2 of 130Te

Preliminary result:

130Te: T1/2 = [ 7.6 ± 1.5 (stat) ± 0.8 (syst) ] 1020 y

Preliminary result:

130Te: T1/2 = [ 7.6 ± 1.5 (stat) ± 0.8 (syst) ] 1020 y

S + B = 607 events

109 events454 g

534 daysS/B = 0.25

background subtracted

NEMO-3 NEMO-3


Energy sum of the electrons Energy sum of the electrons

Cut at 1.5 MeV

E1 + E2 (MeV)

Preliminary results: T1/2 (2) = [4.4 +0.5

-0.4 (stat) ± 0.4 (syst)] × 1019 y

T1/2 (0) > 1.3 × 1022 y (90% C.L.) m < 29.6 eV (90% C.L.), eff. 22%

Preliminary results: T1/2 (2) = [4.4 +0.5

-0.4 (stat) ± 0.4 (syst)] × 1019 y

T1/2 (0) > 1.3 × 1022 y (90% C.L.) m < 29.6 eV (90% C.L.), eff. 22%

133 events7g

948 daysS/B = 6.76

NEMO-3

New results for 48Ca


NEMO-3

Angular distribution

High bkg here due to contamination with 90Sr


Cut at 0

NME: E. Caurrier et al., Phys. Rev. Lett. 100 (2008) 052503.

New results for 96Zr


[1] M.Kortelainen and J.Suhonen, Phys.Rev. C 75 (2007) 051303(R).[2] M.Kortelainen and J.Suhonen, Phys.Rev. C 76 (2007) 024315.[3] F.Šimkovic et al., Phys.Rev. C 77 (2008) 045503. N

ME

:

9.4 g925 days

S/B = 1

NEMO-3 NEMO-3

Angular distributionEnergy sum of the electrons

Preliminary results:

T1/2 (2) = [2.3 ± 0.2(stat) ± 0.3 (syst)] × 1019 y

T1/2 (0) > 8.6 × 1022 y (90% C.L.) m < (7.4 – 20.1) eV [1–3]

Preliminary results:

T1/2 (2) = [2.3 ± 0.2(stat) ± 0.3 (syst)] × 1019 y

T1/2 (0) > 8.6 × 1022 y (90% C.L.) m < (7.4 – 20.1) eV [1–3]

New results for 2 of 150Nd

Preliminary result:

150Nd: T1/2 = [ 7.20 +0.25-0.22 (stat) ± 0.73 (syst) ] 1018 y

Preliminary result:

150Nd: T1/2 = [ 7.20 +0.25-0.22 (stat) ± 0.73 (syst) ] 1018 y


Angular distributionEnergy sum of the electrons

0 results for 150Nd

2 bkg + radioactive bkg MC

radioactive bkg MC

0 MC (T1/2 = 1.45×1022 y)

150Nd

Above 2.5 MeV28.6 ± 2.7 events expected from

background29 events observed


Light neutrino exchange:LEP CLs statistical method above 2.5 MeVDetection efficiency: 19%

NME: V.A. Rodin et al., Nucl. Phys. A 766 (2006) 107.

Previous result: T1/2 > 1.7 × 1021 y (90% CL)

A.A. Klimenko et al., Nucl. Instr. Meth. B 17 (1986) 445.

Right-handed currents:

Emission of Majoron (M1):

T1/2 (0) > 1.45 × 1022 y (90% CL)

m < 3.7 – 5.1 eV

T1/2 (0) > 1.45 × 1022 y (90% CL)

m < 3.7 – 5.1 eV

T1/2 (0) > 1.27 × 1022 y (90% CL)T1/2 (0) > 1.27 × 1022 y (90% CL)

T1/2 (0) > 1.55 × 1021 y (90% CL)T1/2 (0) > 1.55 × 1021 y (90% CL)

[1] M.Kortelainen and J.Suhonen, Phys.Rev. C 75 (2007) 051303(R). [2] M.Kortelainen and J.Suhonen, Phys.Rev. C 76 (2007) 024315. [3] V.A.Rodin et al., Nucl.Phys. A 793 (2007) 213.

NME:

Results for 100Mo and 82Se

693 days of data, Phase I + Phase II (data until spring 2006)


NEMO-3

100Mo

NEMO-3

82Se

T1/2 (2) = [ 7.11 ± 0.02 (stat) ± 0.54 (syst) ] 1018 y

(Phys. Rev. Lett. 95 (2005) 182302)

T1/2 (0) > 5.8 × 1023 y (90% CL)

m < (0.8 – 1.3) eV [1–3]

T1/2 (2) = [ 7.11 ± 0.02 (stat) ± 0.54 (syst) ] 1018 y

(Phys. Rev. Lett. 95 (2005) 182302)

T1/2 (0) > 5.8 × 1023 y (90% CL)

m < (0.8 – 1.3) eV [1–3]

T1/2 (2) = [ 9.6 ± 0.3 (stat) ± 1.0 (syst) ] 1019 y

(Phys. Rev. Lett. 95 (2005) 182302)

T1/2 (0) > 2.1 × 1023 y (90% CL)

m < (1.4 – 2.2) eV [1–3]

T1/2 (2) = [ 9.6 ± 0.3 (stat) ± 1.0 (syst) ] 1019 y

(Phys. Rev. Lett. 95 (2005) 182302)

T1/2 (0) > 2.1 × 1023 y (90% CL)

m < (1.4 – 2.2) eV [1–3]

0 decay search

expected sensitivities in 2010:100MoT1/2(0) > 2 × 1024 y (90 % CL)

m < (0.4 – 0.7) eV

82SeT1/2(0) > 8 × 1023 y (90 % CL)

m < (0.7 – 1.1) eV

Collaboration decided to perform blind analysisAnalysis is now under wayResults will be ready soonData acquisition with NEMO 3 until the end of 2010


[1] M.Kortelainen and J.Suhonen, Phys.Rev. C 75 (2007) 051303(R). [2] M.Kortelainen and J.Suhonen, Phys.Rev. C 76 (2007) 024315. [3] V.A.Rodin et al., Nucl.Phys. A 793 (2007) 213.

NME:

From NEMO 3 to SuperNEMO

N90A

T1/2 (0) > ln 2 M Tobs NA A Nexcluded


7 kg 100 – 200 kg isotope mass M

8 % ~ 30 %

isotope 100Mo 150Nd or 82Se

NEMO 3 SuperNEMO

internal contamination 208Tl and 214Bi in the foil

A(208Tl): < 20 Bq/kg

A(214Bi): < 300 Bq/kg

A(208Tl) < 2 Bq/kg

if 82Se: A(214Bi) < 10 Bq/kg

T1/2(0) > 2 × 1024 y

m < (0.3 – 0.6) eV

T1/2(0) > 2 × 1026 y

m < (50 – 100) meV

energy resolution (FWHM) 8% @ 3 MeV 4% @ 3 MeV

efficiency

SuperNEMO Collaboration

~ 90 physicists, 12 countries, 27 laboratories

MoroccoFes U

United KingdomUCL

U ManchesterImperial College

FranceCEN Bordeaux

IPHC StrasbourgLAL ORSAYLPC Caen

LSCE Gif s/YvetteSpainU ValenciaU ZaragozaU Barcelona

USAMHCINL

(U Texas)Russia

JINR DubnaITEP Moscow

Kurchatov Institute

JapanU Saga

KEKU Osaka

Slovakia(U Bratislava)

UkraineINR Kiev

ISMA Kharkov

Czech RepublicCharles U Prague

CTU Prague

PolandU Warszawa

FinlandU Jyväskylä


SuperNEMO preliminary design


• Planar geometry

Source (40 mg/cm2) 12 m2 , tracking volume (~ 3000 channels) and calorimeter (~ 1000 PMT)

• Modular (~ 5 kg of enriched isotope/module)

100 kg: 20 modules ~ 60 000 channels for drift chamber ~ 20 000 PMT channels (3000 if bar design)

Top view5 m

1 m

Side view

4 m

February 2006 – July 2009

Approved in UK, France and Spain. Smaller but vital contributions from USA, Russia, Czech Republic, Japan.

Main tasks and deliverables:– R&D on critical components

• Calorimeter energy resolution of 4% at 3 MeV• Optimisation of tracking detector and construction (robot)• Better background rejection (e.g. extra veto counters)• Ultrapure source production and purity control • Simulations and geometry optimisation (B-field question)

– Technical Design Report– Experimental site selection (Modane, Canfranc, Gran Sasso)

SuperNEMO design study


Choice of isotope


Choice of nucleus depends on:

• enrichment possibilities

• high Q value

• phase space factor G0

• 2 half-life

• purification of 4 kg of 82Se underway (INL, USA)• enrichment of 150Nd possible in France

(MENPHIS facility at CEA – Atomic Vapour Laser

Isotope Separation)

= G M m22

T0

1

Two main options:

150Nd 82Se

Q (MeV) 3.367 2.995

G0 (y-1eV-2) 8×10-25 10-25

82Se obtained by centrifugation.Impossible for 150Nd, only laserenrichment.

Calorimeter R&D


• Energy resolution is a combination of energy losses in the foil and calorimeter E/E • Goal: FWHM 7%/E 4% at 3 MeV • Studies

– Material: organic (plastic or liquid)– Geometry and shape (block or bar)– Size– Reflective coating– PMTs (Photonis, Hamamatsu, ETL)

• High QE• Ultra-low background

Calorimeter R&D status


• Focus on large block studies (~ 20 cm, 8” PMT)• Four routes pursued

– 8” PMT + plastic block– 8” PMT + liquid scintillator– 8” PMT + hybrid (liquid + plastic) scintillator– 2 m scintillator bar with 3” or 5” PMTs

• PMTs– Working closely with manufacturers: Hamamatsu, Photonis, ETL– Real breakthrough in high-QE PMTs from Hamamatsu, Photonis: 43% QE from 3’’ PMTs, now working on 8’’– Deep involvement in ultra-low background PMT development (especially Photonis)

• 8% at 1 MeV achieved with 20 cm blocks, standard PMT (27% QE) and reflectors • Extrapolating the above improvements gives 7% but must be tested once all components are in hand• Plan B: 3”/5” high QE PMTs and larger number of channels• Decision on calorimeter design in December 2008


• Optimise operating parameters: – wire length and diameter– wire material, gas mixture – readout

• Several single cells, two 9-cell prototypes built and tested• 90-cell prototype is being built

9-cell prototype in Manchester

Tracker R&D

Drift cell working in Geiger mode (Geiger cell)■ Transverse position from electron drift times■ Longitudinal position from plasma propagation times

Tracker automated wiring


• About 500 000 wires to be strung, crimped, terminated• Wiring robot is being developed at Mullard Space Science Lab (UCL)

Pair of end fittings

Anode wire feed mechanism

Clamp mechanism

Radiopurity measurement


Tracking(wire chamber)

Scintillator + PMT

Source foilto be measured

e–

Prompt e–, T0

Delayed T1/2 ~ 300 ns, Edeposited ~ 1 MeV

Radon + neutron + shield

• BiPo detector to measure contaminations of 208Tl and 214Bi in source foils before installation in SuperNEMO• Goal: ~ 5 kg of foil (12 m2 , 40 mg/cm2) in one month with a sensitivity of

A(208Tl) < 2 Bq/kg & A(214Bi) < 10 Bq/kg

Background < 1 event/month!

(164 s)

(300 ns)

232Th

212Bi(60.5 mn)

208Tl(3.1 mn)

212Po

208Pb(stable)3

6%

238U

214Bi(19.9 mn)

210Tl(1.3 mn)

214Po

210Pb22.3 y0.

021%

Bi-Po process

BiPo-1capsule

BiPo-1capsule

BiPo-1:18 capsules in operation in LSM Modane since February 2008current sensitivity A(208Tl) < 5 µBq/kg

BiPo-2 and Phoswhich:installed in LSM Modane and running since July 2008results expected by the end of 2008

BiPo-2

Set of BiPo-1 capsules


Radiopurity measurement

2007 2008 2009 2010 2011 2012 2013

NEMO 3 running

Running full detector in 2014

Target sensitivity (0.05 – 0.1 eV) in 2016

Construction of Construction of 20 modules 20 modules

SuperNEMO modules installation at new LSM

BiPoinstallation BiPo running @ Canfranc

1 – 5 SuperNEMO modules running at Canfranc

2014

SuperNEMO scheduleLadislav Vála, Results of NEMO 3 and status of SuperNEMO, NOW 2008, 9th September 2008

BiPo1Canfranc/LSM

BiPo construction

Construction of 20 modules

Preparation of new LSM site

SuperNEMO 1st module construction

SuperNEMO design study

Summary

NEMO 3 Unique approach combining tracking and calorimetry 2 factory precise T1/2 measurement for 7 isotopes: new results for

48Ca, 96Zr, 130Te and 150Nd 0 of 100Mo & 82Se: blind analysis of Phase 2 data under way Data taking until the end of 2010 Ideal test bench for SuperNEMO

SuperNEMO 3 year design study addresses most critical issues: calorimeter resolution,

tracker optimisation, radio-purity Based on design study results full proposal for 100+ kg detector in 2009 Start-up in stages due to modular approach: first module by 2010/11, all 20

modules ~ 2013 Target sensitivity 50 – 100 meV by 2016


Backup slides

Backup slides


isotope foils

scintillators

PMT

calibration tube

cathode rings (wire chamber) iron shielding

coil

water tank


1 ton of charcoal @ –50oC, 9 barsair flux = 150 m3/hInput: A(222Rn) 15 Bq/m3

Output: A(222Rn) < 15 mBq/m3 !!!reduction factor of 1000

Phase I : February 2003 – September 2004 (radon background in data)~ 1 0-like event/y/kg with 2.8 < E1+E2 < 3.2 MeV

Radon background for 0 searchis then negligible for Phase 2

Radon background for 0 searchis then negligible for Phase 2

Radon trapping facility

Inside the NEMO 3 tent: factor of 100 – 300

Inside NEMO 3: factor of 10A(222Rn) 2 mBq/m3

Phase II : since October 2004 (radon level reduced by a factor of 10)

(164 s)

238U

214Bi(19.9 mn)

210Tl(1.3 mn)

214Po

210Pb(22.3 y)0.

021%

Bi-Po process

0.015 Bq/m3


T1/2 = [ 7.11 ± 0.02 (stat) ± 0.54 (syst) ] 1018 y

Phys. Rev. Lett. 95 (2005) 182302

T1/2 = [ 7.11 ± 0.02 (stat) ± 0.54 (syst) ] 1018 y

Phys. Rev. Lett. 95 (2005) 182302

219 000 events6914 g

389 daysS/B = 40

cos(ee)

● Data

2 MCsimulation

Background subtracted

Angular distribution

● Data

2 MCsimulation


219 000 events6914 g

389 daysS/B = 40

E1 + E2 (MeV)


Phase I data (February 2003 – October 2004) with radon

2 decay of 100Mo


Now we have 0.5M events and the result will be updated later this year

NEMO-3 NEMO-3

T1/2 = [ 9.6 ± 0.3 (stat) ± 1.0 (syst) ] 1019 y

Phys. Rev. Lett. 95 (2005) 182302

T1/2 = [ 9.6 ± 0.3 (stat) ± 1.0 (syst) ] 1019 y

Phys. Rev. Lett. 95 (2005) 182302

2750 events932 g

389 daysS/B = 4

● Data

2 MCsimulation


E1 + E2 (MeV)

Phase I data (February 2003 – October 2004) with radon

2 decay of 82Se


NEMO-3


External background 208Tl (PMTs) Measured with (e) external events~ 10-3 0-like events y-1·kg -1 with 2.8<E1+ E2<3.2 MeV

~ 0.1 0-like events y-1·kg -1 with 2.8<E1+ E2<3.2 MeV

208Tl impurities inside the foils Measured with (e2), (e3) events coming from the foil

External neutrons and high energy ’s Measured with (ee)int events with E1+E2 > 4 MeV

0.02 0-like events y-1·kg -1 with 2.8<E1+ E2<3.2 MeV

NEMO 3 can measure each component of its background!

100Mo 2 decay T1/2 = 7.1 × 1018 y ~ 0.3 0-like events y-1·kg -1 with 2.8<E1+ E2<3.2 MeV

Background measurement in NEMO 3


Future extension of LSM Modane lab


Main HallMain Hall40 × 15 m (h=11 m)

RAILWAY TUNNEL

ROAD TUNNEL Ultra-Low

backgroundFacility

15 × 10 m (h=8 m)

Old Laboratory20 × 5 m (h=4.5 m)

installations, clean rooms

& offices

Access gallery

Characteristic of the

new LSC

Depth 900 m (2450 mwe)

Main experimental hall

600 m2 (oriented to CERN)

Low background lab

150 m2

Clean room 45 m2 (100/1000 type)

General services

135 m2

Offices 80 m2

- BiPo- SuperNEMO- Dark matter- …

New LSC Canfranc laboratory



150Nd laser enrichment

Vaporised isotope mixture

Laser beam

Enriched Ucollecting plate

Depleted U collecting plate

AVLIS: Atomic Vapour Laser Isotope Separation

Selective photo-ionisation: based on isotope shifts in the atomic absorption optical spectraU + 3 selective photons → 235U+ + e–

• 150Nd enrichment is technically possible• MENPHIS facility (CEA/Pierrelatte - France)


200+ kg of 2.5% enriched Uranium produced MENPHIS

AVLIS facility

• Facility stopped in 2003• Principal agreement by CEA to suspend closure/dismantling• 150Nd enrichment collaboration formed. SuperNEMO and SNO++ plus other

interested parties• Phased approach

– Feasibility studies for high degree enrichment (> 50%)– ~ kg production and tests– 100+ kg production

results of nemo 3 and status of supernemo

Documents

results of nemo

new results

russialadislav vla

caladislav vla

zrladislav vla

double beta decayladislav

single b decay

measure t12