1 / 38

Double beta decay and astroparticle projects in IEAP CTU ( NuPECC , Prague, 2011)

Double beta decay and astroparticle projects in IEAP CTU ( NuPECC , Prague, 2011). I van Štekl Institute of Experimental and Applied Physics, CTU in Prague . List of projects : 1) TGV experiment – measurement of 2 n EC/EC decay of 106 Cd

curry
Télécharger la présentation

Double beta decay and astroparticle projects in IEAP CTU ( NuPECC , Prague, 2011)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Double beta decay and astroparticle projects in IEAP CTU (NuPECC, Prague, 2011) Ivan Štekl Institute of Experimental and Applied Physics, CTU in Prague List of projects: 1) TGV experiment – measurement of 2nEC/EC decay of 106Cd 3) NEMO 3 experiment – measurement of 0n and 2nbb decay of several isotopes 4) SuperNEMO – R&D, measurement of 0nbb decay of 82Se or 150Nd 5) Pixel detectors in bb decay – COBRA (CdTe), SPT (Si pixel det.) 5) PICASSO – detection of dark matter 6) CZELTA – detection of cosmic rays Close cooperation with underground lab. – LSM (France), LNGS (Italy), SNOLab (Canada)

  2. IEAP CTU was established 1. 5. 2002 by the CTU Rector as an educational and research institute of CTU oriented toward the physics of microworld and its applications (experimental base of CTU for the research in particle and subatomic physics being performed in international experiments). Research programme of the IEAP: (1) High energy physics and development of corresponding detection systems (CERN, Atlas experiment). (2) Neutron nuclear physics, physics of atomic nuclei, neutrino physics and astroparticle physics (JINR Dubna, French institutions, BNL, ILL Grenoble, TU Munich, University of Montreal and University of Alberta). (3) Applied nuclear spectroscopy and development of detection techniques. Medipix project (X –ray and neutron radiography, imaging, tomography, ...). Radiation hardness of detectors. CIAA.

  3. results utilization of Si pixel detectors Search for double electron capture in 106Cd (TGV collaboration) Since 2000, focus on 2nEC/EC decay of 106Cd JINR Dubna; IEAP CTU in Prague; CSNSM Orsay; Comenius university (Bratislava), Kurchatov institute (Moscow)

  4. TGV-2 Detectors: 32 HPGeØ 60 mm x 6 mm Sensitive volume 20.4 cm2 x 6 mm Total sensitive volume~ 400 cm3 Total mass ~3 kg Double beta emitters: 16 samples (~ 50 µm ) of 106Cd (enrich.75%) 13.6 g ~ 5.79 x 1022 atoms of 106Cd

  5. Phase I Phase II EC/ECT1/2 ≥ …(90%CL)T1/2 ≥ … (90%CL) (0+→0+,g.s.) 3.0 x 1020 yr 4.2 x 1020 yr (0+→2+1,512) 4.2 x 1019 yr 1.2 x 1020 yr (0+→0+1,1334) 3.1 x 1019 yr 1.0 x 1020 yr 0res.(0+→4+,2741) - 1.7 x 1020 yr 0res.(0+→ ?,2716) - 1.6 x 1020 yr β+/EC (0+→0+,g.s.) 5.9 x 1019 yr 1.1 x 1020 yr (0+→2+1,512) 5.9 x 1019 yr 1.1 x 1020 yr (0+→0+1,1334) - 1.6 x 1020 yr β+ β+ (0+→0+,g.s.) 6.0 x 1019 yr 1.4 x 1020 yr (0+→2+1,512) 5.7 x 1019 yr 1.7 x 1020 yr 2β+ β+ (0+→0+,g.s.)- 1.3 x 1020 yr (N.I.Rukhadze et al., Nucl.Phys. A 852 (2011)197-206)

  6. How it compares with calculations > 4.2 1020 p.w. closed approaching

  7. Plans on near future 23 g of 106Cd with enrichment of 98.4 % Planned measurements with 106Cd: • TGV-2 (Ge detectors) (~15 g) • 600 cm3 HPGe detector (~8 g) (modes with g) • SPT (Pixel detectors) (~8 g)

  8. Approaches to double beta studies K1 K1 K2 TGV II GERDA SuperNEMO CUORE COBRA Setup based on semiconductor detectors Semiconductor + segmentation Detector = source Tracking + scintillator Low-temp. detector Pixel R&D projects COBRA extension SPT(EC/EC) • Segmented CdTe pixel detectors (enriched Cd) • Signature = two tracks of electrons from one pixel, Bragg curve • Particle identification / rejection (alpha, electrons, photons) • Si pixel detectors in coincidence mode • Thin foil of enriched isotope • Signature = two hitted pixels with X-rays of precise energy • Efficiency (factor 2x comparing with TGV II) • Particle identification (alpha, electrons) K1 K1 K2 K2 Observable:2× 21keV X-rays from 106Pd daughter originated in the enriched Cd foil Double-side event Single-side events

  9. Experiment NEMO-3 and SuperNEMO NEMO experimentNeutrino EttoreMajoranaObservatory • netrinoless and two-neutrinos double beta decay, several isotopes- 100Mo, 82Se, 130Te, 116Cd, 96Zr, 48Ca, 150Nd • start of operation year 2003; from October 2004 with radon free air (tracking detector, calorimeter, 10 kg of isotopes, located in LSM) • end of operation January 2011 !!!!!!!!

  10. SuperNEMO project (France, UK, Czech Republic, Russia, Spain, USA, Japan, Ukraine, Finland, Slovakia ) Tracko-calo with 100 kg of 82Se or 150Nd T½ > 2. 1026 yr <mn> < 0.05 – 0.11 eV Modules based on the NEMO3 principle Measurements of energy sum, angular distribution and individual electron energy 3 years R&D program: improvement of energy resolution Increase of efficiency Background reduction ……. 100 kg 20 modules R&D funded by France, UK, Spain, Russia, Czech Republic 2010-2011: TDR 2011: commissioning of first module in LSM (France) (2013 ready) 2015: Full detector running

  11. Main activitiesofthe IEAP stafffor SuperNEMO: • Rnmeasurements and R&D programme • Ultra low background facilitybased on high volume HPGe • Testingfacilitiesofscintillatingdetectors Ultra low background facilitybased on high volume HPGe – produced by Canberra, 600 cm3, detector is in LSM (from November 2010); FWHM (122 keV) = 1,13 keV FWHM (1,33 MeV) = 1,98 keV measured relative efficiency = 162% P/C ratio = 113 installation in LSM – January-March, 2011 (frame + Pb shielding = 23 kE). Testingfacilitiesofscintillatingdetectors – prototype is ready in FMPChU(mechanical part, electronic part, X-Y motion are ready; source of electrons with different energies was produced by JINR for us). ENVINET company produces 140 scintillating blocks for X-wall + 40 Veto blocks of SuperNEMO demonstrator tracker (80kE, financed by JINR + Czech Republic) => testing in Prague. schedule: April 2011 – October 2011.

  12. Apparatus for measurement of radon diffusion Left side = high Rnactivity [activity Rn 38 kBq/m3, dry air flow through Rn source 0.34 l/min], Right side =low Rn activity [background 7±3 events per day], Both sides are divided by testing foils. Long term measurements of Rn activities on both sides. 1/2 - Left/right vessel 3 - Radon source 4 - Flow-meter 5 - Sensors of temperature, humidity, and pressure 6 - Air dryer 7 - Air buffer 8 - Air pump, 0.5 l/mini

  13. Apparatus for measurement of radon low activity (1mBq/m3) – step to 1 m3 detector • Stainless steel box, inside 4x50L hemispheres made of wire net with PIN diodes • HV = 5-15 kV, airtight box flushing by measured air • Using 4x 50L detectors instead of one 200 L detector - hoping to increase the efficiency of radon detection. • Present status – measurement of background, calibration of efficiency. • Future plans – test in LSM. 130 cm 70 cm 70 cm

  14. Emulsion of superheatedfreon(C4F10) droplets embedded in a polymerized gel

  15. Main activitiesofthe IEAP stafffor PICASSO: Rnmeasurements and suppression Low background measurements Constructionofdetectors containers (3. generation)

  16. CZELTA • CZEchLarge-area Time coincidence Array – Czech Technical University in Prague – Silesian University in Opava, Czech Republic • The hardware andthedetection station design thesame as isused in theALTA experiment (Alberta Large-area TimecoincidenceArray, University of Alberta, Canada). 10 pieces produced in IEAP CTU. • The sparse network for the detection of high energy cosmic rays (>1014eV). • Stations are installed at roofs of high schools->educational impact. • At present, 7 running detection stations in CR, 1 in Slovakia, 1 in Romania (data are saved on common server, web interface). • We build the global network of detection stations on the Earth = huge „telescope” for detection of cosmic rays showers.

  17. PC HV Detection station Primary particle Scheme of the scintillating detector Interaction in the atmosphere • 3 scintillators (60 x 60 x 1.5 cm) with photomultipliers in a triangle with a site ~10 m, work in a coincidence=> detection of showers with the energy> 1014 eV. • GPS for precise time-labeling of detected showers (precision ~16 ns) => it is possible to study space and time coincidence of the detected showers. Shower of secondary particles U [V] channel 1 channel 2 channel 3 t [ns]

  18. Dt Analysis of coincidence of distant showers - first results • We search for pairs of showers from different stations coming in a short time window. No information of direction of showers was used. • Data from 21 stations (ALTA+CZELTA) analysed. • Double-coincidences on large distances • No significant excess of coincidences. • Bayes estimation of the event rate of the non-background coincidencies using data from all pairs of stations: f < 2.6 yr-1 (c.l. 95%) • Tripple-coincidences on large distances • No significant excess • Using the directions of showers will significantly reduce the statistical background.

  19. CZELTA with other relative detection networks is the first really global network for the detection of high energy cosmic rays (all sub-networks use the same hardware,all data are available on-line from one web-page). • Precise measurement of time => the project is designed for study of correlations of showers on very large distances. • Secondary purpose of the project is to attract young students from high schools to physics, mathematics and computer sciences. We have good experience with these students after they come to Prague to study at a university – they continue to work in our institute.

  20. Conclusion: • Broad involvement of IEAP CTU in underground physics (neutrino physics, dark matter) • Detection of high energy cosmic rays • Development of detection technique (pixel detectors) • International cooperation (France, Germany, Canada, Russia, Slovakia, …) • Responsibility of Czech team in experiments.

  21. Thank you very much for your attention

  22. SPT setup proposal Estimation of limit for EC/EC decay of 106Cd for 1 pair of Timepix quads: If background = 0 : T1/2 > (e . t . Nat . ln2) / ln (1-CL) = 1,95 × 1020 years 90% CL ln (1-CL) = 2.3 e ...... full efficiency (for SPT = 8,54 %) t ...... time of measurement [years], expected 4 years Nat ... number of 106Cd atoms in foil, 98% of enrichment  Nat = 1.89 × 1021 atoms To reach limit of 1021 years: We would need 5-7 quad Timepix pairs in 1. prototype (for 8 gr. we need 25-30 quad pairs)

  23. Decay modes + signatures 1+ 106Ag 0+ 4+ 2741.0 106Cd 2717.6 ++ +/ECEC/EC 1.25% 2741 2229 1160 1557.7 3+ Q(EC/EC) = 2770 keV  7.2 0+ 1133.8 ++4 511(+  for e.s.)  622 1046 +/EC KXPd + 2511 (+  for e.s.) 2+ 511.9 2νEC/EC 2KX Pd (~21 keV) (+  for e.s.) Main background: Cd KX-rays (~23 keV)  511.9 0+ 0νEC/ECKXPd + LXPd +2741(2229 + 512) 106Pd 0νEC/EC 2KXPd +(1160 + 1046+ 512)

  24. Schedule of TGV II experiment: (in Laboratoire Souterrain de Modane, France) Phase I ~ 10g (12 samples) of 106Cd (75%) T= 8687h (Feb.2005 – Feb.2006) Phase II ~ 13.6 g (16 samples) of 106Cd (75%) T ~ 12900h (Dec.2007 – July 2009) Background I no samples (Aug.2009 – Mar.2010) Background II 16 samples of Cd.-nat(Apr.2009 – …2011)

  25. Phase II, 13.6g of 106Cd, T=12900h KXPd KXCd ROI ROI KXCd ROI KXPd ROI

  26. Type of interaction of ϰ with ordinary matter • Two types: coherent (C) and spin dependent (SD) • Coherent: σ(C) ~ A2 >> for heavy nuclei (A > 50) • Spin Dependent: σ(SD) ~ J(J + 1) λ2 >> depending on λ and other factors (J is the nuclear spin, λ related to the magnetic moment of nucleus) • Future could be: Bromotrifluoromethane Halon, BrF3C (A = 80)

  27. Operation of SDD(Superheated Droplet Detector) Emulsion of superheatedfreon(C4F10) droplets embedded in a polymerized gel Pressurizable detection module External piezo-electric sensors Holds an elastic polymer matrix that protects the superheated droplets The recoiling nucleus triggers the phase transition Liquid droplet explodes and creates a gas bubble Droplets mean size ~ 150 mm PICASSO uses acoustical detection - piezo sensors - amplifiers - ADC’s - VME DAQ (First application by B. Hahn and S. Spadavecchia for detection of fission fragments 1960)

  28. Hardware of the detection station Metal tube with other cables: - high voltage for photomultiplier - signal cables from photomultiplier - cable to testing LED diode - cable for controlling of thermostat Thin metal tubewith cable 230 V Socket of 230 V (heating) GPS antenna Meteorological station Thermostat Wooden box With scintillating detector Outer box with temperature insulation Heating cable

  29. Electronics Crates GPS receiver PC UPS

  30. Web-based interface

  31. Web-based interface

More Related