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Neutrinoless Double Beta Decay Neutrino-less double beta decays and Majorana neutrinos Hiro Ejiri RCNP Osaka Univ. CTU Prague 1.Majorana neutrinos and ββ Decays 2. Neutrino-less 0νββ experiments 3. Nuclear responses for ββ neutrinos 4. Concluding remarks. From the Ejiri’s weekend house at Shounan Thank PAVI organizers 1. Majorana neutrinos and neutrino-less ββ decays 0νββ A = B + β + β Lepton number ΔL=2 beyond SM. Part. ν ppyhysics Majorana ν, mν CP 0ν 0ν 0ν 2 T = G [M mν] FEMT(fm) NlNucl. m icro-lblab. Nucl. physics. gA Cosmology short-range & DM to selectively enhance ττσ σ correlation Leppgtogenesis . ν-exchange 1. 0νββ, processes and experiments A. Energy spectra to select the 0νββ 2-body kinematics B. Θ21 and E12 correlations to identify LHC/RHC ν-mass /M/ ML/MR ΘRL W(Θ)= 1 +αcos θ α = −1, +1 C. Different isotopes and states with different M0ν to see light-ν, SUSY, and others. R PAVI SUSY R=(-)3B+L+2S ν matrix and masses . m3 m2 ΔmS ~9 meV m1 ΔmA ~45meV νe νμ ντ m2 νe νμ ντ m3 m1 NH IH Absolute mass scale 2 <m< mν>=|> = |Σ Ui exp(i φi)m) mi| is given by using Ui ΔmS, ΔmA given by ν oscillations D. Effective ν mass regions studied by ββ experiments QD 100~300 meV KKDC 320meV NEMO3 CUORITINO IH: 20-50 meV NH: 2 - 5 meV θ13 QD: Cosmological 200 ~ 300 meV 2 2 1/2 Phase +/- ~ 2 IH/NH ~ 10 Single β ~ mν = [Σ Ui mi ] ~ 300 meV Mass sensitivities and nuclear sensitivity -１/2 eff -1/2 1/2 <mν> = SN (N ) δ -１/2 2 -１/2 eff 0ν 1/2 SN ＝13 (GM /0.01 A) Ν = ε N ton y, δ ~ (BN) Rodin RQRPA QRPA Suhonen Jastraw UNICOM ) (0ν 10 s M s tt rix elemen 1 tt Nuclear ma Nuclear 0.1 70 80 90 100 Ge Se Mo Cd Te Xe A M0ν ~ 24 /R = 18/A1/3 M； excited state and Nd M＝M/3 Neutrino mass sensitivity and ββ detectors -１/2 0ν -1/2 1/2 <mn> meV= (SN) (ε N) δ 0ν 2 82 0ν SN = G M /0.01A/170) Se, ε = 0.3 B=1/t y(σ :1.5%) M~18/A -１/2 0ν SN =10 meV ε ~ 0.3 100 Small N <0.5 δ = 2.3 in meV ss -1/2 N-1/2 <mν> = 45 N Larger N δ ~1.7 (BN)1/2 IH rino mas rino <m > = 25 N-1/4 B1/4 tt D. ββ-sourcesν to be used. 10 IH: 1 t y ~ 0.5 t-2 y N-1/4 tive neu tive NH: 500 t y ~100 t-5 y cc NH Effe 1 E. ΒG. RI, 2νββ 0.01 0.1 1 10 100 1000 IH B ~ 1 /t y σ ~ 2.2 % N ton year NH B ~ 0.2 /t y σ ~ 1.5 % 2. DBD experiments From the Ejiri’s weekday flat at Yokohama Signal of 0νββ and RI BG schematic spectra Calorimetric. Detector=Source Spectroscopic Detector ≠Source Low Q, RI-BG, sharp-peak high Q, low RI, Broad-peak KKDC Resolution 82 Se: ΔEsum = 5.3%(FWHM) 40 2νββ: 40mg/cm2 2 ) 2νββ: 20mg/cm 30 0νββ: 40mg/cm2 0νββ: 20mg/cm2 20 ( 10 0 2νββ 2700 2800 2900 3000 3100 3200 E1+E2 [keV] 0νββ claim by KKDC H. 1. PRL 83 ’99 > 5.7 10 25 y 90% < 0.19 eV 2Ph2. Phys. J. 01 >19> 1.9 90 < <033 0.33 eV 3. Mod. Phys. 01 0.8—18.3 95 0.11—0.56 eV * 4. KKDC PLB 586 198 04 5. New analysis Phys. Scr T127 2006 40 2.23 1025 y 0.32± 0.03 eV Large dependence on the analysis method. Large inconsistency among the publications on the same data and among the group. NEMO 3: Neutrino Ettore Majorana Observatory 100Mo ββ(2ν) 100Mo Multi-source detector εον = 8%, σ =3.4% T2ν for 82Se, 100Mo, 116Cd, 150Nd To be used for check M0ν 100 23 Mo T1/2 >58> 5.8 × 10 y eV (1.3 – 0.8) > ۄmνۃ E2 CUORICINO PRC 78035502 2008 c. Arnabolid et al., 40.7gr 62Xal M0ν by Rodin 11kgy >3 10 24 y <046eV< 0.46 eV Present limits on 0νββ rates and the ν masses 23 0.32 HM 0580.58 080.8 – 131.3 0.3 0.46 Future projects -1/2 -1/4 <mν>S> ~ SN [Nββ/BG] 0ν 2 A. Select isotopes with large SN = G(M ) and B. Detectors with Nββ, ~0.1 ~1 t , B ~ 1 / t y SNO+ SNO+ Spectroscopic experiments GERDA GERDA • ‘Bare’ enrGe array in liquid argon • Shield: high-purity liquid A rgon / H 2O • Phase I (late 2009): ~18 kg (HdM/IGEX diodes) • Phase II Add ~20 kg new detectors - Total ~40 kg Joint Cooperative Agreement: • Open exchange of knowledge & technologies (e.g. MaGe, R&D) • Intention is to merggpe for 1 ton exp. Select best techniq ues developed and tested in GERDA and MAJORANA The MAJORANA Goal of IH 25 meV with 1 t BG=1/t/y DEMONSTRATOR Module 0.06 t Ge –30-kg of 86% enriched 76Ge crystals for science goal; 60-kg for BG –ultra-clean, electroformed Cu Cryostats 4850’ level at Sanford Lab Start 2015 to get 140 meV by 3 y 0. 03 t Majorana S. Elliott 16 1.EXO200 200 kg 136Xe both scintillation and EXO 136Xe ionization to get σ~1.5%. WIPP, start in 2009 Gratta ν08 2νββ and 0νββ 0.3 eV 2.Ba tagging & GXe R&D to identify 0νββ 2008 Xal production 2012 Data taking M=203 kg B = 200 –20 / t y 24~120 – 14~66 meV Possible SuperNEMO design Planar and modular design: ~ 100 kg of enriched isotopes (20 modules × 5 kg) 1 module: Source (40 mg/cm2) 4 x 3 m2 Tracking : drift chamber ~3000 cells in Geiger mode Calorimeter: scintillators + PM 1 000 PM if scint. blocs ~ 100 PM if scint. bars 1 m 5 m Top view 150Nd (SNO+ ) Q = 3.368 100 - 40meV natural – enriched Nd 1k ton detector with 0.1% of Nd, i.e. 56 – 500 kg 150Nd MOON Detector for IH and NH 0νββ Multilayyper modules, expansion of 2-layy(er ELEGANT V(1990-) A. Energy spectrum PL scintillation B. E-Θ β1, β2 C. Different isotopes Detector ≠ββ source D. Signal N~1-10 ton Multi-layer PL E. BG 2νββ 4.2 ε2ν/10−7 PL σ∼2.2 – 1.5 % BG RI Qββ > 3 MeV Vertex Realistic volume PL V =0.4 K m3/ton H. Ejiri et al., Phys. Rev. Lett. 85 (2000) 2917-2920 . H. Ejjyiri, J. Phys. Soc. Jap an, Invited Review, 74 ()(2005) 2101. H. Ejiri, Mod. Phys. Lett. A, Vol. 22, No. 18 (2007) pp. 1277-1291. H. Ejiri1, et al., European Physics Journal, 162 (2008) 239-250 1 module 16 units NaI PMT 1 unit X&Y fiber planes PL plate PL plate PMT PMT ββ source film MOON 1 prototype detector PL 6 layers, 53x53x1 cc BC408. equ.100Mo, 142g 40mg, 3 layers ELEGANT V 1990 PL Mass sensitivity σ=2.2 % , 1.7 % 1.3 % 1000 B C D QD 100 IH 10 1 0.01 0.1 1 10 100 1000 Run N t y (ton year) Phase I NT ~0. 06 t y =0. 03 ton 2 y σ~2. 2 % QD ~ 120 meV Phase II NT ~0.36 t y =0.12 ton 3 y σ~2.2 % QD/IH ~ 70 meV Phase III NT~ 2 t y =0.48 ton 4 y σ~1.7% IH ~30 meV 3. Neutrino nuclear responses From the Ejiri ’s weekday flat at Yokohama Nuclear τσ responses for ν in β &ββ Nuclear weak responses ββ−ν, solar-ν, supernova ν Fermi- Isospin τ GT Spin Ispspin τσ τ,, τσ ν e e e p,3He n,t W γ π,ρ n p n n n p β-decay, e capture γ-capture, e scattering CER 3He,t t,3He d,2He ν-probe from J-PARC γ from Spring-8, HIGS N RCNP, MSU, KVI Charge exchange reaction at RCNP Osaka ΔE /E~ 7 10-5 3 Mi = 0.59 ( He, t) Frekers Ejiri et al , |GTR> ΔE /E~ 7 10-5 |k ββ Mf = 0.55 β M1 = 0.11 ,,g agree with M2ν = 0.12 (EL V, NEMO) Photon γ 1N1. Neu tra l curren t responses 2. Isospin rotation for charged current responses via IAS 1/2 <f |g Mβ| i> = g/e (2T) <f | emγ | I> Spring-8 E1 and M1 γ P (L) azymuthal distribution γ Τ,Tz-1 Τ− =ΙΑΙΑS γ Β Τ,Τz=5,5 T,Tz=6,6 β ββ Τ,Τ,,Τ,Τz=6z=5,6,5 Α Τ,Τz-1 H. Ejiri PRL 21 ’68, H. Ejiri PR 38 ‘78 Low energy Neutrinos H. Ejiri NIM. 503 (2003) 276 – 278. p + Hg Æ n π+ + + + + π Æ μ +νμ μ Æe + νe + anti- νμ 3 GeV 50 GeV Ep Gev Np /sec Nn/sec 15 15 SNS 1 6 10 1 10 J-PARC J－PARC 312103 1.2 1015 5105 1014 FSQP: Fermi Surface Quasi Particle Model 2νββ matrix elements 1 |GTR> M) SS (F 0.1 2ν M |k XP), EE ( ββ 2ν 0.01 M M2ββ2νββ = Σ g 2 Mβ Mb /Δ k A k k k 0.001 70 80 90 100 110 120 130 140 Mass number A (102: 100Mo excited state) H.
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