1. Integrated Large Infrastructures for Astroparticle Science
N4 - Double beta Network
Dominique Lalanne, Paris, November 19th 2007

2. Month number 48 corresponds to April 2008
9.N4 - Table 2 – DBD - Fourth 18 months Implementation Plan
Tasks and Deliverables
37 th to 42nd month
43rd to 48th month
49th to 54th month
WP 1: COORDINATION OF DBD SEARCHES
Tasks:
1.4
- Common working group with JRA2 on the R&D projects in relation with the NA recommendations and follow-up of those R&D
1.5
- Common working group with the other 2 work packages
Deliverables:
- First version on report on interplay between N4 recommendation and JRA2
- White book on DBD common to all work packages (first version
Month number 48 corresponds to April 2008

3. WP 2: BANK OF PURE ISOTOPES
Tasks:
2.2
- Comparison of radiopurity results obtained by different methods and / or indifferent labs.
2.3C
- Follow-up of ICR technique
- Follow-up of LIS technique
Deliverables:
- Final report on radiopurity issues
- White book on DBD common to all work packages (first version)
WP 3: COLLECTION AND INVESTIGATION OF EXPERIMENTAL INPUTS, NUCLEAR MATRIX ELEMENTS
- Common working group with JRA2 on R&D projects in relation with N4 recommendation and follow-up of those R&D
- Pre-report on interplay between N4 recommendations and JRA2

4. Preparation for the N4 deliverables
Co-ordinator Christine Marquet, CENBG, France
In March 2008, deliverable for N4 network activities
(It must prepare the final 5 years N4 deliverable for march 2009)
Reports on N4:
WG1 : Co-ordination of double beta decay searches
co-ordinator: Xavier Sarazin, LAL-Orsay, France
WG2 : Bank of pure isotopes.
co-ordinator: E. Previtali, INFN Milano, Italy
WG3 : Theoretical developments
co-ordinator: J. Suhonen, Jyväskylä University, Finland
For WG1: we propose that this report will be very similar to the ASPERA roadmap
+ details of the R&D Status of the differents projects
Each project (GERDA, CUORE, and GERDA) has to give an updated status before 30 January 2008 (3 to 5 pages should be OK)

5. Main issues and recommendations
The European next-stage detectors are GERDA, CUORE and Super-NEMO. Cobra is in R&D stage but might be a promising technique.
The three experiments with germanium, bolometers and tracko-calo detectors have skill and experience ready for the next generation of double beta experiments.
These techniques have recent improvements showing capabilities and reliability for possible low level of background which is the main issue for the expected sensitivity on the neutrino mass.
These three experiments could operate their full detector in with a final sensitivity on the effective neutrino mass mbb around 50 meV.
With their sensitivities and complementary experimental approaches the three experiments could prove or disprove the KKGH claim.
Their motivation: exploration of the parameter range predicted by the inverted mass hierarchy.
Our recommendation is to keep these three axes of study in the double beta research field.
With these detectors, Europe will be in the best position to improve sensitivity, maintain its leadership in this field, to prove or discard “degenerate” neutrino mass scenarios, …
… and may be able to finally discover the Majorana nature of neutrino.

6. WP1, deliverables :
- First version on report on interplay between N4 recommendation and JRA2
- White book on DBD common to all work packages (first version)
Most of the work has been done for ASPERA

7. WP2, deliverables :
Final report on radiopurity issues
- White book on DBD common to all work packages (first version)
Work almost done in previous reports
- Updating of the data base of double beta emitters
To be added 38 kg of enriched Ge76
1.5 kg of enriched Se82

8. Pre-report on interplay between N4 recommendations and JRA2
WP3 deliverables :
Pre-report on interplay between N4 recommendations and JRA2
- White book on DBD common to all work packages (first version)
Recommendations correspond to a confidence
on matrix elements of double beta emitters
Work on good tracks

14. ILIAS-JRA2 Integrated Large Infrastructures for Astroparticle Science
Enrichment and purification of Se82
recent delivery : 1.5 kilos of enriched Se82 from Tomsk

15. 1.5 kg from Tomsk

16. New deliverables : purified Selenium
by chemistry INL (Idaho) kg of Se82 done
by distillation Kurchatov kg of Se (nat.) done
IChHPS (Russia) kg of Se (nat.) done
Conclusion : a lot of measurements to be done on Germanium detectors in LSM

17. 82Se Purification for SuperNEMO
J. D. Baker Idaho National Laboratory
C. A. McGrath Idaho National Laboratory
C. S. Sutton Mount Holyoke College
A. M. Caffrey Mount Holyoke College
J. Horkley Idaho State University
ISU, Pocatello, ID
November 8, 2007

18. Se Purification • Weigh Se
• Add quartz distilled 6 M HNO3 to dissolve Se
• Heat until dryness
• Add nanopure H2O
• Add quartz distilled 2 M HCl
• Add barium solution (First time)
• Add H2SO4, precipitate carries Ra
• Filter Solution (first time)

19. Se Purification continued
Add barium solution (Second time)
Filter Solution (second time), improves separation from Ra
Add saturated Na2S2O5, reduces Se to metal which precipitates, SO2 would be better
Let the solution stand
Filter Se
Combine filtrates and reduce volume, precipitate Se metal
Rinse the Purified Se
Add Se to quartz boats, place boats in furnace, dry Se under He purge.
Weigh ultra-purified Se
Add ultra-purified Se to clean shipping container

20. Natural Se Purification Results
Sample
(mBq/kg)
Mass (g)
Measurement time (h)
40K
60Co
137Cs
226Ra
228Ra
228Th Ru
natural Se
196
447.33
668 ± 31
< 1
2.1 ± 0.9
46 ± 2
13 ± 2
11 ± 2
485
Purified natural Se
563
436.56
< 20
< 0.7
1.0 ± 0.4
< 0.9
< 2.4
< 1.6 3
Reduction
Factor
< 33
---
< 51
< 5.4
< 6.9
162

21. Nd source production
Enrichment : MENPHIS, still under discussion, but lasers will NOT be dismantled
collaboration between SuperNEMO and SNO+, Nd150, November 7th, 2007
for enrichment and purification
Source shaping for SuperNEMO : open question
Chair person for source production (Se and Nd) : Corinne Augier

22. Purification of Nd liquid scintillator Xiongxin Dai Queen’s University SNO+ collaboration meeting, May 30th, 2007

23. Backgrounds for neutrinoless double beta decay
1yr, 1000kg natural, 150meV

24. A reduction of >106 is required!!!
Radio-purification goals:
228Th and 228Ra in 10 tonnes of 10% Nd (in form of NdCl3 salt) down to <110-14 g 232Th/g Nd
Raw NdCl3 salt measurement: 228Th equivalents to 32±2510-9 g 232Th/g Nd
A reduction of >106 is required!!!

25. Requirements for Nd Radio-purification Techniques
Very high efficiency for 228Th and 228Ra
No significant Nd loss after purification
No significant pH change
No addition of other impurities, which can interfere with the Nd-LS synthesis
Fast
Low cost
Safe

26. Extraction efficiency
Spike test results: Extraction efficiencies of Th and Ra in 10% NdCl3 using HZrO and BaSO4
Purification
method
Adsorbent
Conc
Extraction efficiency
228Th
226Ra
HZrO coated filter
10 g Zr/m2
53.1±2.4%
<10%
HZrO mixed-in
0.1 mg/g Zr
0.44 mg/g Zr
0.82 mg/g Zr
<5%
99.06±0.22%
99.89±0.02%
30.7±5.7%
30.1±9.0%
BaSO4 coated filter
10 g Ba/m2
BaSO4 mixed-in
1.0 mg/g Ba
9.5±4.7%
63.4±1.9%
BaSO4 co-precipitation
0.49 mg/g Ba
1.39 mg/g Ba
20.4±4.4%
62.8±2.3%
97.2±0.2%
99.89±0.03%

27. Proposed purification methods for 10% NdCl3 aqueous solution
Step 1 (BaSO4 co-precipitation for Ra):
- add BaCl2 solution into 10% NdCl3, and mix well for 30min;
- add (NH4)2SO4 solution, and Ra co-precipitates with BaSO4, mix for 30min;
- let precipitate settle, and filter the purified NdCl3 supernatant solution
Step 2 (HZrO mixed-in purification for Th):
- Prepare HZrO absorbent: neutralize ZrCl4 with NH4OH, separate the precipitate and rinse with UPW;
- add HZrO into 10% NdCl3, mix for 2 hours to extract Th onto HZrO;

28. Total NdCl3: 10 tonnes of 10% Nd solution
Nd purification plant
Total NdCl3: 10 tonnes of 10% Nd solution
Purification goal: <110-14 g 232Th/g Nd
Turn-around time:
- 200L/batch, 2 batches/week → 25 weeks
- Nd purification can be done in parallel with the Nd-LS production
The design of the Nd purification plant has started at Queen’s

29. New chair persons for ILIAS
N4 : chair Christine Marquet
deputy Xavier Sarazin
JRA2, enrichment and purification :
chair Corinne Augier