ILIAS-N4 Search on Double Beta decay
-Coordination of double beta decay searches-Bank of pure isotopes-Negociations with Russian labs-Theoretical developments
Integrated Large Infrastructures for Astroparticle Science
D.N4 – Table 1 – Third 18 months Execution Plan
WP25th to 30th month
01.04.2006-30.09.200631st to 36th month
01.10.2006-31.03.200737th to 42nd month
01.04.2007-30.09.2007
1Coordination of DBD
searches
Tasks
- Background issues for the next generation of detectors- Comparisons among different techniques and recommendations on the most promising ones
- Common working group with JRA2 on the R&D projects in relation with the N4 recommendations and follow-up of those R&D
Milestones and
Deliverables
- Final report on background issues - Report on recommendation on the most appropriate techniques
- First version on report on interplay between N4 recommendations and JRA2
2 Bank of
pure isotopes
Tasks- Constitution of a data base of a Bank of isotopes- Study of possible enrichment by laser isotope separation (LIS)
- Comparison of radiopurety results obtained by different methods and / or indifferent labs.
Milestones and
Deliverable
- Updating of isotopes data base- First report on laser isotope separation (LIS)
- Pre-report on radiopurety issues- Final report on laser isotope separation (LIS)
3Collection and investigation
of experimental inputsnuclear matrix elements
Tasks
- Common conclusions of the year 2 working groups and isotope selection for new generation of experiments
- Common working group with JRA2 on R&D projects in relation with N4 recommendation and follow-up of those R&D
Milestones and
Deliverable
- Report on conclusions on matrix element computation and selected isotopes
- Pre-report on interplay between N4 recommendations and JRA2
9.N4 - Table 2 – DBD - Third 18 months Implementation Plan
Tasks and Deliverables 25th to 30Th month 31th to 36th month 37th to 42th month
WP 1: COORDINATION OF DBD SEARCHES
Tasks:
1.4 - Background issues for the next generation of detectors
1.5- Comparison among different techniques and recommendations on the most promising ones
1.6- Common working group with JRA2 on the R&D projects in relation with the N4 recommendations and follow-up of those R&D
Deliverables:
- Final report on background issues
- Report on recommendation on the most appropriate techniques
- First version on report on interplay between N4 recommendation and JRA2
WP 2: BANK OF PURE ISOTOPES
Tasks and Deliverables 25th to 30Th month 31th to 36th month 37th to 42th month
Tasks:
2.2- Constitution of a data base of a Bank of isotopes
2.3C- Study of possible enrichment by Laser Isotope Separation
- Comparison of radiopurety results obtained by different methods and/or indifferent labs.
Deliverables:
- Updating of isotope data base
- First report on Laser Isotope Separation (LIS)
- Pre- report on radiopurety issues
- Final report on Laser Isotope Separation (LIS)
WP 3: COLLECTION AND INVESTIGATION OF EXPERIMENTAL INPUTS, NUCLEAR MATRIX ELEMENTS
Tasks and Deliverables 25th to 30Th month 31th to 36th month 37th to 42th month
Tasks:
- Common conclusions of the year 2 working groups and isotope selection for new generation of experiments
- Common working group with JRA2 on R&D projects in relation with N4 recommendation and follow-up of those R&D
Deliverables:
- Report on conclusions on matrix element computation and selected isotopes
- Pre-report on interplay between N4 recommendations and JRA2
WP1
Deliverable: Final report on background issues
http://idea.dipscfm.uninsubria.it/frontend/exec.php?id_folder=22
GERDA
A major improvement in sensitivity compared to previous experiments can only be achieved by a reduction of the level background.
Present level (IGEX and Heidelberg-Moscow experiments) 10-1 counts/(kg·keV·y) at 2039 keV
GERDA phase I (15 kg of existing 76Ge diodes from the IGEX and HM envisaged background index 10-2 cts/(kg·keV·y).
GERDA phase II (40 kg of enriched Ge76). Minimization of cosmic ray exposure and segmented detector readout will help to reduce the background index by another order of magnitude.
If phase I and II do not show positive evidence for 20 -decay, an O(500 kg) experiment would be necessary to reach the 10 meV scale for the effective neutrino mass. For background-free operation of such an experiment it is necessary to suppress the background index below 10-3 counts/(kg·keV·y).
The background suppression techniques developed in phase I and II of GERDA will show the way to such a large scale background-free experiment that can only be performed in a worldwide collaboration.
Figure 1: CUORICINO background in the 20 region. From left to right are visible: 238U 2448 keV peak, 60Co 1173+1332 keV peak, 232Th
2615 keV peak. The20-decay signal is expected around 2530 keV.
Cuoricino-CUORE
The present results are:- successful selection of most materials with the desired radiopurity ,- high sensitivity fast technique to analyze special materials (lead and copper),- surface treatment procedure with ultra pure materials to remove any contamination from crystals and copper surfaces (both the procedures can probably be exported to other kind of crystals and materials),
The global result achieved after employing these techniques was the reduction of the background level by a factor at least 2 with respect to CUORICINO . A study of the origin of the residual background being on the way.
Once projected into CUORE, whose structure was designed in order to minimize the more critic contribution to background such as those due to surface contaminations, the resulting background is of about 2-4 10-2 count/(keV.kg.y).
NEMO
Using simulation, for each kind of background, the number of expected events in the window 2.8-3.2 MeV for the 100Mo source
is estimated to 1.5 10-3 counts/(keV.kg.y). The contribution to this background is:
7 10-4 counts/(keV.kg.y) of 100Mo 22-decay,
4 10-4 counts/(keV.kg.y) due to 214Bi coming from radon,
3 10-4 counts/(keV.kg.y) given by 208Tl contaminations in 20 sources,
5 10-5 counts/(keV.kg.y) due to the external neutrons and high-energy g-rays.
3 10-6 counts/(keV.kg.y) produced by 214Bi and 208Tl in the glass of the PMTs,
Figure 2: NEMO Experiment - two-electron energy sum spectrum for like emitted from 100Mo sources.
SuperNEMO
The sources activities should be less than
2 Bq/kg for 208Tl
10 Bq/kg for 214Bi in the case of the Se82 source (300 Bq in the case of Nd150, so much lower constraint for radon).
For all the materials of the detector, including radon (except in the case of Nd150) and the glass of the PMTs, the activities should be divided by a factor 10. With such specification the total background will be 5 10-5 counts/(keV.kg.y). The objective is to reach a sensitivity on the effective Majorana mass of neutrino of ~ 50 meV.
Bank of pure isotopes.
Ezio Previtali, Piero Benetti, Massimiliano Clemenza, Dominique Lalanne
Co-ordinator : E. Previtali, INFN, Milano, Italy Deputy Co-ordinator: D. Lalanne, LAL, IN2P3, France
Some new production of isotopes : 2 kg of enriched selenium for NEMO GERDA experiment had received in the last June 37.5 kg of germanium
The Ion Cyclotron Resonance (ICR) approach was presented to the ILIAS community and a Letter of Intent (LOI) was prepared for a Design Study (DS) to be submitted to the 7th Framework Program (FP7)
ICR
Costing, Timescale. Experts from CEA have estimated in 12 million Euros the cost of an ICR, including also the personnel,
having a throughput of 100 kg/year/isotope, at 50% of enrichment level and starting with an isotopic abundance
around 5%. Different raw material inputs or isotopic enrichments are possible and the throughput will change accordingly. The unit should be operating within 5 years,
design phase included.ICR Applications. The production of isotopes can be crucial
for many applications in physics and in other sciences: we will try to indicate some possible interesting items that can be
potentially covered with a dedicated ICR facility:
Double beta decay: many interesting isotopes can be enriched; in particular 48Ca and 150Nd can be produced with
a reasonable throughput, while other techniques show no chance or very little capabilities.
Medicine: stable isotopes for diagnostic and therapeutic applications can be prepared: in particular some interesting stable precursors of radioactive elements can be easily prepared. A very short list can contain: 112Cd, 50Cr, 102Pd, 58Fe, 203Th,… In particular the ICR machine of Theragenics was specifically built with
the DOE support for 102Pd enrichment.
Nuclear industries: in future high quantities of 157Gd, 64Zn, 90Zr, 58Ni, 54Fe, 97Mo, … will be requested.
Scientific research: some enriched isotopes are of specific interest for some research activities: 43Ca, 168Yb, 44Ca, 48Ca, 58Ni, 50Cr, 76Ge, 82Se, 150Nd,
100Mo,…
Negociations with Russian labs for Se82 production
Tender in June 2006 for a production of 1.5 kilo of enriched Se82
ECP-Krasnoyarsk…
…and SURPRISE : a second answer : Chemgas (France)
Choice done for Chemgas (better price)
According the procedure, not possible to make a different choice
All possible sites in Russia are (and Chemgas is in touch with all of them) :
For Se82, it seems the choice of Chemgas is Tomsk
Actually Alexander Barabash thinks that the 2 kilos tagged « ITEP-Kurchatov »were produced in Tomsk (September 2006 announcement !). Question: did hereally know that long ago or not, but at my last questioning in June 2006 at Santa Fe he confirmed me that the 2 physicists of Kurchatov were doing the job. (But I have still no report on this from Kurchatov (!))
MENPHIS reconversion to 150Nd
3 phases :
Phase 1 : 6 months, 2 persons, study of new parameters : report done
Present situation : under discussion between CEA and IN2P3
decision of CEA not yet made, but dismantling is the first option
real issue : a framework of funding and manpower
IF POSITIVE DECISION :
Phase 2 : restart of the facility, new collector to be designed tests with new lasers, purchasing of 3 tons of natural Nd (2007-2008)
POSSIBLE PRODUCTION OF A FEW KILOS (up to 10…)
Phase 3 : tests, tuning, running (2009)
Recent news
- study of Commissariat à l’énergie atomique (CEA) on the feasibility of enrichment of Nd150
-International statement for a large production (SNO+, Moon, SuperNEMO, DCBA), July 2006
-Strong letters of support for a Nd150 production from Art Mac Donald (SNO+) and Frank Avignone
- Discussions between IN2P3 and CEA on the subject
Signatories :
José Díaz (Spain), Juan-Jose Gomez (Spain), Serge Jullian (France), Dominique Lalanne (France), Karol Lang (Texas, USA), Julio Morales (Spain), Fabrice
Piquemal (France), Ruben Saakyan (UK), Federico Sánchez (Spain), (SuperNEMO collaboration)
Josh Klein (Texas), Gene Beier (Pensylvania), (SNO+ collaboration)Richard Hahn, Minfang Yeh (Brookhaven National Laboratory, USA, SNO+)Mark Chen, Aksel Hallin, Aksel Hallin, Christine Kraus, Art McDonald, Peter
Skensved, (Queen's University, Canada, SNO+)Clarence Virture (Laurentian University, Canada, SNO+)
Franz von Feilitzsch (Germany), SNO+ collaborationHiro Ejiri (Japan), Masaharu Nomachi (Japan), Masher Monarchy (Japan), (MOON
collaboration)Nabuhiro Ishihara (Japan), (DCBA collaboration)
Letter of Interest for Double Beta Decay Experiments with Neodymium 150July 2006
Theoretical studies
NDM06 Symposium in Paris, November 3-9, 2006:
very interesting discussions between theoreticians on the comparison of QRPA and shell model calculations see web site http://
Work on NME in Tuebingen, Bratislava and Jyväskylä groups
Tuebingen group
A. Faessler, M. Gozdz, V. Rodin, M.Y. Saleh, F. Šimkovic, R. Dvornický, P. Beneš,
The continuum-QRPA, which is the most advanced version of the QRPA,
has been developed for the first time to calculate 2-decay and 0-decay amplitudes. A systematic analysis of the double-beta decaying nuclei is being performed within the approach. Calculation results for 130Te and 76Ge
Bratislava and Tuebingen groups.
A version of the QRPA for deformed nuclei is being currently developed to take into account realistic residual interactions
The ultimate goal of this activity is to calculate 0-decay nuclear matrix elements for such an interesting candidate as 150Nd.
The calculation of the QRPA Hamilton matrices is in progress.
Jyväskylä theory group
J.Suhonen, M.Kortelainen, J.Toivanen
The calculation of nuclear matrix elements for neutrinoless double beta decay has been focused on means of testing the underlying theory frameworks with independent data.
This independent data comes from beta decays, the nuclear muon capture and charge-exchange reactions.
