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Reactor neutrinos, double beta and beta decays Experimental review. Fabrice Piquemal Laboratoire Souterrain de Modane ( CNRS/IN2P3 and CEA/IRFU) and Centre d’Etudes Nucléaires de Bordeaux-Gradignan ( Univ . Bordeaux I and CNRS/IN2P3). ICHEP 2010 July, 28 2010 Paris.
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Reactor neutrinos, double beta and beta decays Experimentalreview Fabrice Piquemal Laboratoire Souterrain de Modane (CNRS/IN2P3 and CEA/IRFU) and Centre d’Etudes Nucléaires de Bordeaux-Gradignan (Univ. Bordeaux I and CNRS/IN2P3) ICHEP 2010 July, 28 2010 Paris
Neutrino properties • - Oscillation parametersin 2q13 • Absolute neutrino mass • - Nature of neutrino (Dirac ≠ or Majorana = ) • - Neutrino mass scale • Right HandedCurrent • - Majoron • ……
m2sol =m212 = (7.58 0.21) 10-5 eV2 Oscillations parameters and neutrino mass Mixing angles Atmospheric (SK) Accelerators (K2K,Minos) Solar (SNO, SK) Reactors(KamLAND) Reactors (CHOOZ) Accelerators (JPARC) ,b : CP Majoranaphase tan223=1.0 ± 0.3sin2213 < 0.16tan212=0.47 ± 0.05 CP:CP Dirac phase Mass hierachy Absolute neutrino mass Beta decay : |mn| = S |Uei| mi< 2.6 eV (90 % CL) Double beta : <mee> = |S U2ei mi| < 0.3 – 0.7 eV (95% CL) Cosmology : mn= m1 + m2 + m3< 0.5 – 1 eV (95 % CL) m2atm =m231 = (2.2 0.2 ) 10-3 eV2
Reactor neutrinos Clean measurement of q13 Negligeablemattereffect No CP effect Liquid scintillator for gtagging Eth = 1.8 MeV n + p e+ + n Liquid Scintillator (loaded with Gd) Prompt signal from e+ Slowing down of the neutron Delayed signal ~100 ms from n capture on H (2.2 MeV g) or Gd (7 MeV g) Transparent buffer with PMT
Reactor neutrino results CHOOZ KamLAND+ Solar neutrinos Sin 2q13 < 0.16 (90 %CL) L (m) NP B Vol; 188 2009, 84-89
Reactor neutrinos CHOOZ LIMIT sin 2q13 < 0.16 (90% CL) Errors on the ratio Nobserved/NexpectedStatisticalerror =2.8% , Systematicalerror= 2.7 % 3 experiments to improve sin 2q13sensitivity : Double Chooz (France), Daya Bay(China) RENO (South Korea) SeetalksMasakiHishitsuka, Cheng-Ju Lin, Soo-Bong Kim Near detector to cancel somesystematics: Cross section, flux fromreactor, cutefficiency Higherstatistic: More powerfulreactors, longer time of running, larger mass of target sstat= 0.2 – 0.5 % , ssyst=0.4 – 0.6% sin 2q13 < 0.01 – 0.03 Backgrounds correlatedwith muons spallations (depth and muons tagging) Uncorreleted background fromnaturalradioactivity (low radioactive materials)
Reactor neutrinos Near (Sept. 2012) Far (2012) Lingao near (2012) Daya Bay Near (2011) Far (Sept. 2010) 2 reactors 8,5 GWth 6 reactors 17.4 GWth Near (2010) Far (2010) 6 reactors 17.3 GWth
averaged neutrino mass Beta decay (A,Z) (A,Z+1) + e- + ne Direct measurement by cinematics dN/dE ~[ (E0-Ee)2 – mi2]1/2: MAC-E spectrometers 3 Fraction of decay in [Qb – mn, Qb] ~ (mn/Qb) MAINZ:m2 = -0.6 ± 2.2 ± 2.1 eV2 mn< 2.3 eV (95% C.L.) C. Kraus et al., Eur. Phys. J. C 40 (2005) 447 lowestQb value3H (Qb= 18.6 keV) High counting rate Low background Energyresolution ~ mn TROISK:m2 = -2.3 ± 2.5 ± 2.0 eV2 mn< 2.05 eV (95% C.L.) But systematics from end-point fluctuations not included
KATRIN experiment Improvement of DE:0.93 eV (4.8 eV for Mainz) Largeracceptance Statistics100 days1000 days 3 yr of data (5 y real time) Tests of main spectrometer 2011 Complete system integration 2012
1 mm MARE experiment MicroBolometers of ArReO4 187Re Qb = 2.47 keV(T1/2=4.4 1010 yr) Full energymeasurement No systematicfrom source But time response of sensor pile-up MARE-I: 300 detectors FWHM ~20 eV t ~100 – 500 ms mn< 2 –4 eV ( 5 years) MARE – II : 5000 detectors (~2018) FWHM ~20 eV t ~1 – 5 ms mn< 0.2 eV (10 years) MIBETA 10 detectors mn2 = -141 211 stat 90 sys eV2 Studies for 163Ho Electron capture QEC ~2.6 keV, T1/2 = 4600 yr mn< 15 eV (90% c.l.)
-1 T1/2= F(Qbb,Z) |M|2<mee>2 Neutrinoless double beta decaybb(0n) (A,Z) (A,Z+2) + 2 e- DL=2 Non-conservation of leptonicnumber Majorana neutrinos Test of new physics :Right HandedCurrent, Majoron, SUSY,… Light neutrino exchange 5 <mee>= m1|Ue1|2 + m2|Ue2|2.eia1 + m3|Ue3|2.eia2 |Uei|: mixingmatrixelement,a1 et a2: Majorana phase M . t e A (y) e A (y) M . t Experimentally NBckg. DE NO Background With Background
bb(0n) observables bb(0n) bb(2n) Electron energysum From G. Gratta Mass mechanism Mass mechanism RHC RHC Angular distribution Ee1 – Ee2 distribution 150Nd distribution s arxiv: 1005.1241v1 [hep-ex]
bb(0n): isotope choice 2.614 MeV Highest gamma-ray fromnaturalradioactivity Double beta decay isotopes Nuclearmatrixelements From F. Simkovic (neutrino 2010)
Effective neutrino mass and q13 Isotope mass Required background level ~ 10 kg 2011 100 – 1000 cts/yr/ton ~ 100 kg 2015 1 – 10 cts/yr/ton ~ 1000 kg 0.1 – 1 cts/yr/ton |mee| Heidelberg-Moscow (2001) ~11 kg of enriched Ge bb(0n) ? S T Petcov 2009 J. Phys.: Conf. Ser.173 012025 Nextstep ~ 100 kg experiment 2011 - 2015
bb(0n) : experiments and projects NEMO3/SuperNEMO (82Se, 150Nd, 48Ca) NEXT (136Xe) SNO++ (150Nd) DCBA (150Nd) EXO (136Xe) Majorana (76Ge) EXO gaz (136Xe) Cuoricino/CUORE (130Te) GERDA (76Ge) COBRA (116Cd) CANDLES (48Ca) KamLAND (136Xe) MOON (100Mo) Tracko-calo Source detector Calorimeter Source = detector b b b b
Cuoricino Thermometer Double beta decay 5.3 kg.an 208Tl (232Th chain) T1/2 > 1. 1024 ans (90%) <mn> <0.5 – 2.4 eV 60Co pile up 214Bi (238U chain) bb(0n) Energy (keV) Bolomètres: CUORICINO Bolometers of TeO2(33.8% of 130Te) (Qbb= 2.528 MeV) 41 kg of natTe 11.6 kg of 130Te Heat sink DE/E ~ 8 keVat 2 527 keV Bckg: 0.169 cts/keV/kg/yr Crystal absorber See talk A. Nucciotti
NEMO 3 Tracko-calo detector e- Vertex E1 Drift chamber (6000 cells) Plastic scintillator + PMT (2000) 10 kg of isotopes Multi-isotopes DE/E (FWHM) : 8 % @ 3 MeV e- E2 bbevent Bckg: 0.025cts/keV/kg/yr See talk Ch. Marquet 100Mo, 7 kg, 1275 days, 620 000 events Also T1/2 (2n) and T1/2 (0n) for 48Ca, 150Nd, 116Cd, 96Zr, 130Te, 82Se and excited states, majoron, etc….
100 kg experiments Seetalks A. Nucciotti, Ch. Marquet Step by stepapproach GERDA Ge diode in LAr CUORE130Te bolometers GranSassolaboratory GranSassolaboratory CUORE-0 39 kg of natTe 13 kg of 130Te Data taking 2011 CUORE 200 kg Data taking 2013 (scintillatingbolometres ?) 2010: 18 kg of 76Ge (HM and IGEX crystals) 1st results 2011 2012: 40 kg of 76Ge + Energyresolution + Natural Te + Energyresolution SuperNEMOtracko-calo MAJORANA Ge segmented Diode Modane laboratory DUSEL laboratory Module-0 7 kg of 82Se (150Nd) Data taking 2013 20 Module 100 kg Data taking 2015 2011: 20 kg of natGe 2013 ? : 30 kg of 76Ge + Background rejection + Multi-isotopes + Energyresolution
100 kg experiments Agressive approach Seetalks Carter Hall, Alfredo Thomas, Masayuki Koga EXOliquidXenon SNO++ Ndsalt + liquidscintillator WIPPL laboratory SNOLAB laboratory 2010: 200 kg of 136Xe Results 2013 Ba tagging R&D 2010: 740 kg of natNd (44 kg of 150Nd) Dissolved in scintillator + Large mass + Possibility to tag daughter nucleus + Large mass + low background detector NEXT Xe high pressure TPC KamLAND-ZenXe + liq. scintillator Canfranclaboratory Kamiokalaboratory 2011: 1 kg of 136Xe 2013 : 100 kg 2011: 400 kg of 136Xe Dissolved in liq. scintillator + Large mass + low background detector + Background rejection
Summary Measure of sin 2q13withreactor neutrinos2015sin 2q13 < 0.01 – 0.03 Direct mvmeasurement2017 mn < 0.2 eV Double beta decay2013 – 2018 100 kg experiments<mee> < 40 -100 meV Need to know the results for 1 ton experimentchoice (isotope, technique) If discovery, tracking detector needed to determine the process
Schedule for data taking Tunnel blastingcompleted Near detector (DB) ready in 2011 Full detector ready in 2012 Far detector data taking sept 2010 Civil work for near detector Nov. 2010 Near detector data taking 2012 Detector commissionning nov. 2010 Data takingDec;.2010
Detectors LA (260 m.w.e.) x2 740 n/day DB (300 m.w.e.) x2 840 n/day Far (910 m.w.e.) x4 90 n/day Target: 20 t/detector 410 m (120 m.w.e.) 400 n/day 1050 m (300 m.w.e) 40 n/day Target: 8.6 t 290 m (120 m.w.e.) 1280 n/day 1380 m (450 m.w.e) 114 n/day Target : 16 t