Reactor neutrinos double beta and beta decays Experimental
Reactor neutrinos, double beta and beta decays Experimental review Fabrice Piquemal Laboratoire Souterrain de Modane (CNRS/IN 2 P 3 and CEA/IRFU) and Centre d’Etudes Nucléaires de Bordeaux-Gradignan (Univ. Bordeaux I and CNRS/IN 2 P 3) ICHEP 2010 July, 28 2010 Paris
Neutrino properties - Oscillation parameter sin 2 13 -Absolute neutrino mass - Nature of neutrino (Dirac ≠ or Majorana = ) - Neutrino mass scale -Right Handed Current - Majoron ……
Oscillations parameters and neutrino mass Mixing angles Atmospheric (SK) Reactors (CHOOZ) Accelerators (K 2 K, Minos) Accelerators (JPARC) tan 2 23=1. 0 ± 0. 3 sin 22 13 < 0. 16 Solar (SNO, SK) Reactors (Kam. LAND) tan 2 12=0. 47 ± 0. 05 , b : CP Majorana phase CP: CP Dirac phase Mass hierachy Absolute neutrino mass Beta decay : |m | = S |Uei| mi < 2. 6 e. V (90 % CL) Double beta : <mee> = |S U 2 ei mi| < 0. 3 – 0. 7 e. V (95% CL) Cosmology : m = m 1 + m 2 + m 3 < 0. 5 – 1 e. V (95 % CL) m 2 sol = m 212 = (7. 58 0. 21) 10 -5 e. V 2 m 2 atm = m 231 = (2. 2 0. 2 ) 10 -3 e. V 2
Reactor neutrinos Clean measurement of 13 Negligeable matter effect No CP effect Liquid scintillator for g tagging Transparent buffer with PMT Liquid Scintillator (loaded with Gd) + p e+ + n Eth = 1. 8 Me. V Prompt signal from e+ Slowing down of the neutron Delayed signal ~100 ms from n capture on H (2. 2 Me. V g) or Gd (7 Me. V g)
Reactor neutrino results CHOOZ Kam. LAND + Solar neutrinos Sin 2 13 < 0. 16 (90 %CL) L (m) NP B Vol; 188 2009, 84 -89
Reactor neutrinos CHOOZ LIMIT sin 2 13 < 0. 16 (90% CL) Errors on the ratio Nobserved/Nexpected Statistical error =2. 8% , Systematical error= 2. 7 % 3 experiments to improve sin 2 13 sensitivity : Double Chooz (France), Daya Bay (China) RENO (South Korea) See talks Masaki Hishitsuka, Cheng-Ju Lin, Soo-Bong Kim Near detector to cancel some systematics: Cross section, flux from reactor, cut efficiency Higher statistic: More powerful reactors, longer time of running, larger mass of target sstat = 0. 2 – 0. 5 % , ssyst=0. 4 – 0. 6% sin 2 13 < 0. 01 – 0. 03 Backgrounds correlated with muons spallations (depth and muons tagging) Uncorreleted background from natural radioactivity (low radioactive materials)
Reactor neutrinos Far (2012) Near (Sept. 2012) Lingao near (2012) Daya Bay Near (2011) Far (Sept. 2010) 2 reactors 8, 5 GWth 6 reactors 17. 4 GWth Location Thermal Power Distance Near/far Depth Near/far Double Chooz France 8. 5 410/1050 120/300 RENO South Korea 17. 3 290/1380 120/450 DAYA BAY China 17. 4 360/1985 500/1613 260/910 Near (2010) Far (2010) 6 reactors 17. 3 GWth
3 yr data sensitivities sstat (%) ssyst (%) sin 2 13 (90 % CL) Double Chooz 0. 5 0. 6 < 0. 03 RENO 0. 3 0. 5 < 0. 02 DAYA BAY 0. 2 0. 4 < 0. 01
Reactor neutrinos Location Thermal Power Distance Near/far Depth Near/far Target mass (tons) running sstat (%) ssyst (%) sin 2 13 (90 % CL) Double Chooz France 8. 5 410/1050 120/300 8. 6/8. 6 2010 (far) 2012 0. 5 0. 6 < 0. 03 RENO South Korea 17. 3 290/1380 120/450 16/16 Dec, 2010 0. 3 0. 5 < 0. 02 DAYA BAY China 17. 4 360/1985 500/1613 260/910 20 x 2/40 DB 2011 Full 2012 0. 4 < 0. 01
Beta decay (A, Z) (A, Z+1) + e- + e Direct measurement by cinematics MAC-E spectrometers d. N/d. E ~ [ (E 0 -Ee)2 – m i 2 ]1/2: averaged neutrino mass Fraction of decay in [Qb – m , Qb] ~ (m /Qb) 3 H lowest Qb value (Qb= 18. 6 ke. V) High counting rate Low background Energy resolution ~ m 3 MAINZ: m 2 = -0. 6 ± 2. 2 ± 2. 1 e. V 2 m < 2. 3 e. V (95% C. L. ) C. Kraus et al. , Eur. Phys. J. C 40 (2005) 447 TROISK: m 2 = -2. 3 ± 2. 5 ± 2. 0 e. V 2 m < 2. 05 e. V (95% C. L. ) But systematics from end-point fluctuations not included
KATRIN experiment Improvement of E: 0. 93 e. V (4. 8 e. V for Mainz) Larger acceptance Statistics 100 days 1000 days Tests of main spectrometer 2011 Complete system integration 2012 3 yr of data (5 y real time)
MARE experiment Micro. Bolometers of Ar. Re. O 4 187 Re Qb = 2. 47 ke. V (T 1/2=4. 4 1010 yr) Full energy measurement No systematic from source But time response of sensor pile-up MIBETA 10 detectors 1 mm MARE-I: 300 detectors FWHM ~20 e. V t ~100 – 500 ms m < 2 – 4 e. V ( 5 years) MARE – II : 5000 detectors (~2018) FWHM ~20 e. V t ~1 – 5 ms m < 0. 2 e. V (10 years) mn 2 = -141 211 stat 90 sys e. V 2 m < 15 e. V (90% c. l. ) Studies for 163 Ho Electron capture QEC ~2. 6 ke. V, T 1/2 = 4600 yr
Neutrinoless double beta decay bb(0 ) (A, Z+2) + 2 e- L=2 (A, Z) Non-conservation of leptonic number Majorana neutrinos Test of new physics : Right Handed Current, Majoron, SUSY, … Light neutrino exchange 5 -1 T 1/2 = F(Qbb, Z) |M|2 <mee>= m 1|Ue 1|2 + m 2|Ue 2|2. ei 1 + m 3|Ue 3|2. ei 2 |Uei|: mixing matrix element, 1 et 2: Majorana phase Experimentally (y) e M. t A NO Background (y) e A M. t NBckg. E With Background
bb(0 ) observables bb(2 ) bb(0 ) Electron energy sum Mass mechanism RHC Angular distribution From G. Gratta Mass mechanism RHC Ee 1 – Ee 2 distribution 150 Nd distribution s arxiv: 1005. 1241 v 1 [hep-ex]
bb(0 ): isotope choice 2. 614 Me. V Highest gamma-ray from natural radioactivity Double beta decay isotopes Nuclear matrix elements From F. Simkovic (neutrino 2010)
Effective neutrino mass and 13 Isotope mass ~ 10 kg Required background level 2011 100 – 1000 cts/yr/ton ~ 100 kg 2015 0. 1 – 1 cts/yr/ton |mee| ~ 1000 kg 1 – 10 cts/yr/ton Heidelberg-Moscow (2001) ~11 kg of enriched Ge bb(0 ) ? S T Petcov 2009 J. Phys. : Conf. Ser. 173 012025 Next step ~ 100 kg experiment 2011 - 2015
bb(0 ) : experiments and projects NEMO 3/Super. NEMO (82 Se, 150 Nd, 48 Ca) NEXT (136 Xe) SNO++ (150 Nd) DCBA (150 Nd) EXO (136 Xe) Majorana (76 Ge) EXO gaz (136 Xe) Cuoricino/CUORE (130 Te) GERDA (76 Ge) COBRA (116 Cd) Calorimeter Source = detector b Tracko-calo Source detector b b b CANDLES (48 Ca) Kam. LAND (136 Xe) MOON (100 Mo)
Cuoricino Bolomètres: CUORICINO Bolometers of Te. O 2 (33. 8% of 130 Te) (Qbb= 2. 528 Me. V) Heat sink Thermometer Double beta decay Crystal absorber See talk A. Nucciotti 41 kg of nat. Te 11. 6 kg of 130 Te E/E ~ 8 ke. V at 2 527 ke. V Bckg: 0. 169 cts/ke. V/kg/yr
NEMO 3 Tracko-calo detector Drift chamber (6000 cells) Plastic scintillator + PMT (2000) 10 kg of isotopes Multi-isotopes E/E (FWHM) : 8 % @ 3 Me. V Bckg: 0. 025 cts/ke. V/kg/yr See talk Ch. Marquet E 1 e- Vertex e. E 2 bb event 100 Mo, 7 kg, 1275 days, 620 000 events Also T 1/2 (2 ) and T 1/2 (0 ) for 48 Ca, 150 Nd, 116 Cd, 96 Zr, 130 Te, 82 Se and excited states, majoron, etc….
100 kg experiments Step by step approach GERDA Ge diode in LAr See talks A. Nucciotti, Ch. Marquet CUORE 130 Te bolometers Gran Sasso laboratory 2010: 18 kg of 76 Ge (HM and IGEX crystals) CUORE-0 39 kg of nat. Te 13 kg of 130 Te Data taking 2011 1 st results 2011 + Energy resolution 2012: 40 kg of 76 Ge MAJORANA Ge segmented Diode DUSEL laboratory 2011: 20 kg of nat. Ge 2013 ? : 30 kg of 76 Ge + Energy resolution + Natural Te CUORE 200 kg Data taking 2013 (scintillating bolometres ? ) Super. NEMO tracko-calo Modane laboratory Module-0 7 kg of 82 Se (150 Nd) Data taking 2013 + Background rejection 20 Module 100 kg Data taking 2015 + Multi-isotopes
100 kg experiments Agressive approach EXO liquid Xenon WIPPL laboratory 2010: 200 kg of 136 Xe Results 2013 Ba tagging R&D + Large mass + Possibility to tag daughter nucleus Kam. LAND-Zen Xe + liq. scintillator See talks Carter Hall, Alfredo Thomas, Masayuki Koga SNO++ Nd salt + liquid scintillator SNOLAB laboratory 2010: 740 kg of nat. Nd (44 kg of 150 Nd) Dissolved in scintillator + Large mass + low background detector NEXT Xe high pressure TPC Canfranc laboratory Kamioka laboratory 2011: 1 kg of 136 Xe 2011: 400 kg of 136 Xe Dissolved in liq. scintillator + Large mass + low background detector 2013 : 100 kg + Background rejection
Sensitivities 2013 - 2018 Technique Location EXO Liquid Xe 136 Xe WIPP (USA) GERDA Diode Ge 76 Ge Gan sasso (Italy) CUORE-0 CUORE SN module 0 Bolometers 130 Te Gan sasso (Italy) Tracko-calo Modane 82 Se, 150 Nd (France) Super. NEMO Mass kg start Cts/ke. V/kg/yr T 1/2(0 ) 5 yr <mee> me. V 200 2010 0. 002 6. 4 1025 < 109 - 135 18 2010 0. 01 3. 1025 < 250– 380 40 2012 0. 001 3. 1026 < 80 - 120 0. 12 8. 1025 <100 - 200 2. 1 1026 6. 5 1026 < 41 -82 < 23 - 47 13 2011 Bckg 200 2013 0. 01 0. 001 7 2013 0. 0001 6. 1024 < 200 – 600 100 2015 0. 0001 1026 < 53 – 145 SNO+ Liq. Scint. 150 Nd SNOLAB (Canada) 44 2012 Kam. LAND Liq. Scinti 136 Xe Kamioka (Japan) 400 2011 < 100 < 60 (2 yr)
Summary Measure of sin 2 13 with reactor neutrinos Direct mv measurement 2017 2015 sin 2 13 < 0. 01 – 0. 03 m < 0. 2 e. V Double beta decay 2013 – 2018 100 kg experiments <mee> < 40 -100 me. V Need to know the results for 1 ton experiment choice (isotope, technique) If discovery, tracking detector needed to determine the process
Schedule for data taking Tunnel blasting completed 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 Near detector Far detector Double Chooz 2012 2010 RENO 2010 DAYA BAY DB 2011 LA 2012 Detector commissionning nov. 2010 Data taking Dec; . 2010
Detectors 410 m (120 m. w. e. ) 400 /day 1050 m (300 m. w. e) 40 /day Target: 8. 6 t LA (260 m. w. e. ) x 2 740 /day DB (300 m. w. e. ) x 2 840 /day Far (910 m. w. e. ) x 4 90 /day Target: 20 t/detector Collaborations Double Chooz DAYA BAY RENO 290 m (120 m. w. e. ) 1280 /day 1380 m (450 m. w. e) 114 /day Target : 16 t
- Slides: 25