SuperNEMO collaboration

Transcription

1 Jose Busto

2 SuperNEMO Collaboration SuperNEMO collaboration SuperNEMO collaboration ~ 100 physiciens, 10 countries, 24 laboratoires USA MHC INL U Texas UK UCL U Manchester Imperial College Finland U Jyvaskula Poland U Warsaw Russia JINR Dubna ITEP Mosow Kurchatov Institute Japan U Saga KEK U Osaka France CEN Bordeaux LAL ORSAY LPC Caen LSCE Gif/Yvette CPPM Marseille LAPP Annecy Ukraine INR Kiev ISMA Kharkov Slovakia (U. Bratislava) Czech Republic Charles U Praha IEAP Praha

3 SuperNEMO Collaboration SuperNEMO collaboration SuperNEMO collaboration ~ 100 physiciens, 10 pays, 24 laboratoires Goal : Study the fundamental properties of the neutrino USA MHC INL U Texas UK UCL U Manchester Imperial College France CEN Bordeaux LAL ORSAY LPC Caen LSCE Gif/Yvette CPPM Marseille LAPP Annecy Finland U Jyvaskula Poland U Warsaw Russia JINR Dubna ITEP Mosow Kurchatov Institute Ukraine INR Kiev ISMA Kharkov Slovakia (U. Bratislava) Czech Republic Charles U Praha IEAP Praha Japan U Saga KEK U Osaka

4 Neutrinos in the Univers 12 fundamental fermions Q = 0 M not well know

5 Neutrinos in the Univers 12 fundamental fermions Q = 0 M not well know The second most abundant particle in the univers

6 Neutrino Oscillations n e n μ = cosθ sinθ sinθ cosθ n 1 n 2 Flavor eigenstate Mixing Matrix Mass eigenstate P n μ n e = sin 2 2θ sin m 2 L En

7 Neutrino Oscillations n e n μ = cosθ sinθ sinθ cosθ n 1 n 2 Flavor eigenstate Mixing Matrix Mass eigenstate P n μ n e = sin 2 2θ sin m 2 L En Neutrinos oscillation have been observed at low and high energy Neutrino oscillation = > m n 0 = > physics beyond the minimal standard model

8 Neutrino Oscillations n e n μ = cosθ sinθ sinθ cosθ n 1 n 2 Flavor eigenstate Mixing Matrix Mass eigenstate P n μ n e = sin 2 2θ sin m 2 L En Neutrinos oscillation have been observed at low and high energy Neutrino oscillation = > m n 0 = > physics beyond the minimal standard model Open questions : What is the nature of the neutrino : What is the mass hierarchy :...

9 Nature of neutrino Dirac Q neutrino = 0 IF Majorana NOT possible in SM Majorana

10 Neutrino Oscillations n e n μ = cosθ sinθ sinθ cosθ n 1 n 2 Flavor eigenstate Mixing Matrix Mass eigenstate P n μ n e = sin 2 2θ sin m 2 L En Neutrino oscillation = > Dm 0 = > new physics beyond the minimal standard model Open questions : What is the nature of the neutrino : Dirac n n, or Majorana ( n = n ) : What is the mass hierarchy :...

11 Particle Physics without accelerator Particle Physics from very rare decays Single beta decay Weak Interaction n R n R

12 Double beta decay Two neutrinos double beta decay Rare but allowed process T 1/2 = ( )10 20 y even even nucleous Rare ( 48 Ca, 76 Ge, 82 Se, Eve 100 Mo, 130 Te, 150 Nd )

13 Double beta decay Neutrinoless double beta decay D L = 2 Forbidden process Majorana Neutrino n n In addition RHC (V+A) v R, n L Majoron B-L...

14 Neutrinoless Double beta decay

15 Mass Hierarchy and absolute mass scale If dominant process : light Majorana n Current bb experiments Mass Hierarchy Future experiments : start exploring at least the inverse hierarchy area 15

16 (bb) 0n observables (bb) 0n : emission of 2 electrons : at the same time : from the same point : with SE e = Q bb

17 (bb) 0n observables bb(2n) (bb) 0n : emission of 2 electrons : at the same time : from the same point : with SE e = Q bb

18 (bb) 0n observables bb(2n) (bb) 0n : emission of 2 electrons : at the same time : from the same point : with SE e = Q bb Background : natural radioactivity, radon, neutron, muons Exemple : for SuperNEMO radon concentration <

19 Techniques expérimentales How to build a (bb) 0n experiment Take a very thin film of bb nucleous : 82 Se, 130 Te, 150 Nd, b b

20 Techniques expérimentales How to build a (bb) 0n experiment Put the film in the center of a gas tracking detector b b

21 Techniques expérimentales How to build a (bb) 0n experiment Surround the detector with scintillators for énergie and timing measurements b b (bb) 0n : Emission of 2 electrons at the same time from the same point with SE e = Q bb

22 From NEMO 3 to SuperNEMO SuperNEMO is the extrapolation of NEMO III bb experiment Installed in LSM from 2000 to 2010

23 SuperNEMO Single module bb film Modular detector Background study First module (demostrator) running with 82 Se in march ~ 10 kg bb 95 % enrichment - D E ~ 4 3 MeV - Very low radioactive background 2 Electron tracker Scintillator calorimeter Big improvement

24 SuperNEMO au LSM 100m 55m 22,5m 14,9m If background is low enough 20X Single module => ~ 150 kg bb isotope => T 1/2 (0nbb) > ans <m n > < 0.04 ev

25 CPPM CPPM is in charge of radon background - gas purification - radon background transport simulations - radon concentration measurement We need less than 50 atoms of radon on atoms of He Radon trap Spherical detector for quality of the gaz

26 Further information : Jose Busto : busto@cppm.in2p3.fr : : CPPM office n-304