1. Rare Isotopes (Enriched Isotopes for Astroparticle Physics) Ezio Previtali INFN and University of Milano Bicocca Aspera meeting on “R&D and Astroparticle Physics”, Lisbon 8 January 2008

2. IsotopeNatural Abbund Q(ββ) *Enrich. Actual Enrich. Other 48 Ca0.2%42710.54 ICR 76 Ge7.4%20390.73 UltraCent.ICR 82 Se8.7%29951.70 UltraCent.ICR 100 Mo9.6%30345.0 UltraCent.ICR 116 Cd7.5%28021.30 UltraCent. ?ICR 130 Te34.0%25334.26 UltraCent. 136 Xe9.0%24790.28 UltraCent. 150 Nd5.6%336757.0 AVLIS, ICR Rare Isotopes Candidates Double Beta decay experiments Dark Matter experiments Ar element depleted in 39 Ar isotope (under test) Odd nuclei for spin dependent measurements (?) Aspera meeting on “R&D and Astroparticle Physics”, Lisbon 8 January 2008 *F.T. Avignone II et al., New Journal of Physics 7 (2005) 6

3. Actual situation for DBD experiments Isotope Production Mass Natural Abund. Production Enrich. Production Method Production Site PurificatinChemical Form Physical Form Actual Mass Actual Enrich. CustomersActual Exper. Future Exper. 238 U Contam. 232 Th Contam. 130 Te1 kg34 %94 %Ultra Centrifuge KurchatovRecristal. China TeO 2 Crystals800 g TeO 2 73 %INFN Milano CUORICIN O CUORE<10 -11 g/g 128 Te1 kg32 %95 %Ultra Centrifuge KurchatovRecristal. China TeO 2 Crystals800 g TeO 2 82 %INFN Milano CUORICIN O CUORE<10 -11 g/g 136 Xe10 kg9 %64 %Ultra Centrifuge Oak RidgeXeGas10 kg Xe64 %INFN Milano DAMA 100 Mo 9.6 %Ultra Centrifuge RussiaITEPMoMetal2.479 kg 100 Mo 95 %NEMOSNEMO<15 mBq/kg <0.5 mBq/kg 100 Mo9.6 %Ultra Centrifuge RussiaINEELMoComposite4.434 kg 100 Mo 99 %NEMOSNEMO<15 mBq/kg <0.3 mBq/kg 82 Se1 kg8.7 %97 %Ultra Centrifuge RussiaSeComposite932 g 82 Se97 %NEMOSNEMO<25 mBq/kg <4.0 mBq/kg 130 Te34 %89 %Ultra Centrifuge Kurchatov TeO 2 Composite454 g 130 Te 89 %KurchatovNEMOSNEMO<20 mBq/kg <4.0 mBq/kg 116 Cd7.5 %93 %Ultra Centrifuge DistillationCdMetal + Mylar 405 g 116 Cd 93 %NEMOSNEMO<56 mBq/kg ±7 mBq/kg 150 Nd5.6 %91 %Electro magnetic Nd 2 O 3 Composite37 g 150 Nd92 %??INRNEMOSNEMO<66 mBq/kg <23 mBq/kg 96 Zr2.8 %57 %Electro magnetic ChemicalZrO 2 Composite9.4 g 96 ZrITEP + INR NEMOSNEMO<222 mBq/kg <27 mBq/kg 48 Ca0.2 %73 %Electro magnetic CaF 2 Composite7 g 48 CaNEMOSNEMO<15 mBq/kg <6 mBq/kg 76 Ge6 kg7.4 %86 %Ultra Centrifuge KurchatovZone Refining GeHPGe Diodes 6 kg Ge86 %ITEPIGEXGerda<10 -12 g/g 76 Ge11 kg7.4 %86 %Ultra Centrifuge KurchatovGeHPGe Diodes 11 kg Ge86 %Kurchatov MPI Heid. Heidelberg Moscow Gerda<10 -12 g/g 78 Kr99 %Ultra Centrifuge ECP Svetlana INR RAS 136 Xe68 kg9 %80 %Ultra Centrifuge ECP Svetlana XeGas68 kg80%Stanford University EXO 129+131 X e 10 kg80 %Ultra Centrifuge ECP Svetlana XeGasInst Cosm S. Tokyo 82 Se2 kg8.7%96%Ultra Centrifuge KurchatovINEEL 82 SeIN2P3NEMOSNEMO 76 Ge38 kg7.4 %86 %Ultra Centrifuge ECP Svetlana GeMax Plank Inst. Heid. Gerda

4. DBD near future New generation double beta decay experiments detector mass larger than 100 kg highly enriched in  candidates Some example: CUORE 130 Tenatural~600 kg Gerda III 76 Geenriched 86%~1 ton Majorana 76 Geenriched 86%~180 kg SuperNEMO 82 Se/ 150 Ndenriched90%~100 kg MOON 100 Moenriched85%~100 kg EXO I 136 Xeenriched65%~200 kg EXO II 136 Xeenriched65%~1 ton SNO++ 150 Ndenriched90%~560 kg ……… During the next years there will be a large request of enriched isotopes Production must be clean, flexible (many different nuclei) and fast The production mass scale change from few kg to few hundreds kg Cost estimates for all enrichments > 100 M€ (actual prices in Russia with UC) Aspera meeting on “R&D and Astroparticle Physics”, Lisbon 8 January 2008

5. DBD medium term Experiment strategies indicate possible future steps New request of isotope production will begin when actual experiments will start Experimental mass for each experiment can, in principle, grow in the range of 1 ton Possible timescale for new experiments ~15 years Aspera meeting on “R&D and Astroparticle Physics”, Lisbon 8 January 2008 Actual proposed experiments can explore only the inverse hierarchy for m ν To go further we need more DBD mass and less background Same setup can measure different isotopes: CUORE, …. Same detector can be multiplied few times Xe experiments, …. New techniques are under developments Scintillating Bolometers, ….

6. Production quality Very pure isotopes are necessary Normal enrichment production is not so clean After enrichment a purification process is normally needed    sensitivity detector mass [kg] measuring time [y] detector efficiency background background [c/keV/y/kg] energy resolution [keV] isotopic abundance atomic number S 12 0 a.i. A Mt meas Ebkg Aspera meeting on “R&D and Astroparticle Physics”, Lisbon 8 January 2008 A general rule will be: Increasing a.i. without increasing background

7. Production quality A specific example: For MiBetaII experiment we produced 1 kg enriched Te ( 130 Te) Enrichment level was 94% at the production site Material was delivered by the producer in form of TeO 2 Background will be very critical: “old” experiments had background in the range of 0.1 counts/(keV kg y) future experiments are going to the range of 0.001 counts/(keV kg y) Purification will be of primary importance and needs precisely evaluations technically and economically TeO 2 crystals was grown at SICCAS (China): Material was purified few time: it was full of Si Growing procedure was repeated in order to purify the material After growing processes we obtain: Crystals of TeO 2 for a total mass of 800 g Level of enrichments at 73% Background around few 10 -12 g/g in U and Th (10 -13 g/g in natural crystals) Cost for enriched crystal production was ~3 times larger respect to natural Aspera meeting on “R&D and Astroparticle Physics”, Lisbon 8 January 2008

8. Actual production capability USA: Calutron production was stopped in 2004 Medium size ICR machine founded by DOE is installed at Theragenics production is oriented to medicine application New program for AVLIS founded at Livermore (very expensive) it is unclear if this program will be completed Russia: Few labs are able to produce isotopes with Ultracentrifuges Only elements that have gas compounds can be produced Prices of enriched isotopes are favorable (today) Europe and Japan: There are some enrichment facilities based on Ultracentrifuges Restart of an AVLIS machine in France is not yet established ( 150 Nd) Actually practically only Russian labs can produce stable isotopes Aspera meeting on “R&D and Astroparticle Physics”, Lisbon 8 January 2008

9. Possible future strategy (1) It is possible to find an agreement with Russian producers Advantage: - Enrichment plants exist - Actual prices per unit product are low - They have a lot of experience in UC technique Disadvantage: - Only isotopes with UC will be produced - It is not clear at which level can be done an R&D program - Produced materials are normally dirty and need purification - What about future prices? Aspera meeting on “R&D and Astroparticle Physics”, Lisbon 8 January 2008

10. Te-130 in form of metal: Mass - 250 kg Enrichment - > 99% Purity > 99.9% Cost – 9.9 $/g (at FCA, Krasnoyarsk condition) Time 400 days (> 99%) 350 days (> 90%) Cost enriched Te for CUORE 12 April 2005 New quotation was asked from USA group of CUORE October 2007, CUORE meeting at LNGS, F. Avignone report New Cost - 13.0 $/g (indicative) Aspera meeting on “R&D and Astroparticle Physics”, Lisbon 8 January 2008 Possible future strategy (1)

11. Possible future strategy (2) It is possible to restart some production plants in west countries Examples: - AVLIS (SILVA) in France (CEA) is under discussion - USA plants with UC and AVLIS (not realistic) - URENCO machines (UC) in Europe (Prices probably too high) - Discussion with Theragenics for possible use of ICR machine Advantages: - Different sources of production respect to Russian one - R&D programs will be probably much simple - It is possible the production of more isotopes ( 150 Nd using AVLIS or ICR) Disadvantages: - Restart decision must be taken as soon as possible - Some plants are not flexible (AVLIS in France can produce only 150 Nd) - Some plants are dedicated to other productions (medical application) - In general production throughputs are not enough (a part AVLIS) - Actual production cost are 10/100 times larger then Russian Aspera meeting on “R&D and Astroparticle Physics”, Lisbon 8 January 2008

12. Possible future strategy (3) It is possible to realize a dedicated plant in EU. New plant must be configured for: - Flexibility: a maximum number of isotopes must be produced - Clean: a clean production and an integrated purification system are needed - Cheap: production cost must be comparable with the Russian one - Dedicated: possible R&D programs on specific isotope can be possible Advantages: - Production can be configured as requested from the experiments - Specific isotopes production can be studied ( 150 Nd and 48 Ca) - Cleaning procedures can be made in place Disadvantages: - Plant doesn't exist and it must be realized - It is necessary an agreement will all the involved experiments - Decision must be taken soon, time is practically over - Initial investments are not negligible Aspera meeting on “R&D and Astroparticle Physics”, Lisbon 8 January 2008

13. We proposed last year to built an enrichment facility based on an ICR machine: flexible to produce most of the interested DBD isotopes 48 Ca, 76 Ge, 82 Se, 100 Mo, 150 Nd, … throughput : >100 kg/year for various isotopes realization time: 4/5 years The facility can be realized with: Large current separatorICR machine Low current separatorCalutron Chemical supportClean Room, Chemical Labs,.. Cryogenic supportLN2 and LHe, (liquefier?) Analytical systems ICP-MS,.. General supportUPS, mechanical, … There is, actually, no real agreements to work in this direction Aspera meeting on “R&D and Astroparticle Physics”, Lisbon 8 January 2008 Possible future strategy (3)

14. Conclusions Production of Rare Isotopes will be a crucial issue for future experiments Production capability must be clearly evaluated technically and economically Purification of enriched nuclei must be considered as a very important aspect Analysis must be done on short and medium timescale It is very difficult to define an agreement between different experiments Aspera meeting on “R&D and Astroparticle Physics”, Lisbon 8 January 2008 Actual production cost (for enrichments) is favorable, for the future …….

15. from: G. Yu. Grigoriev, Kurchatov Institute, Moscow Ion Cyclotron Resonance separation Aspera meeting on “R&D and Astroparticle Physics”, Lisbon 8 January 2008

16. But the proposed infrastructure will be not a production facility Scientist can directly participate at source preparation Production can be, in principle, tuned to fulfill experimental request Production costs This infrastructure will be competitive with present production in Russia? As our knowledge actual prices are (examples): 76 Ge~60 €/g 82 Se~120 €/g For these elements we evaluate a general cost between 40 and 80 €/g Moreover it is possible to enrich also nuclei like 48 Ca and 150 Nd Aspera meeting on “R&D and Astroparticle Physics”, Lisbon 8 January 2008

17. By-products Many enriched isotopes for various application can be produced Some of these cannot be massive produced with other techniques Some examples: Medicine (diagnostic and therapy) 112 Cd, 50 Cr, 102 Pd, 58 Fe, 203 Th, …. Industry 157 Gd, 64 Zn, 90 Zr, 58 Ni, 54 Fe, 97 Mo, …. Research 43 Ca, 44 Ca, 48 Ca, 50 Cr, 58 Ni, 76 Ge, 82 Se, 100 Mo, 150 Nd, 168 Yb, … The main advantage of this approach is Flexibility Aspera meeting on “R&D and Astroparticle Physics”, Lisbon 8 January 2008