Non-Oscillation Neutrino Physics Jason Detwiler Lawrence Berkeley National Laboratory DPF 2009, Detroit, MI July 31, 2009
ν Questions • What is the mass scale? • What is the hierarchy? • Does ν = ν ? Normal Inverted • What are the precise oscillation parameters? • Is θ 13 > 0? • Is CP violated in the ν sector? • Do sterile ν exist? • What can ν tell us about From presentation by S. King at UKNF (Dec 2005), available at the sun, Earth, SN, C ν B, ... http://hepunx.rl.ac.uk/uknf/2005-05-04/uknf-sfk-pheno.ppt
Kinematic and Cosmological Experiments
Kinematic Measurements tritium experiments
KATRIN Monitor Provide stable source tritium column Transport electrons Reject low-energy Precise energy selection recycle tritium electrons of electrons parameters density Rear Source Trans/pump Pre-spectrometer Main spectrometer Detector � e 3 H 10 3 e - /s 1 e - /s 10 10 e - /s 10 10 e- /s e - e - e - e - � -decay 1.7 x 10 11 Bq Si pin (0.3 mT) diode 3 He 3 He 3 He 3•10 -3 mbar 10 -11 mbar 10 -11 mbar ± 1 kV -18.4 kV -18.574 kV B = 3 T B = 6 T 70 m Δ E = B min /B max x 18.6 keV = 93 eV → m ν < 200 meV
Neutrino Mass Scale kinematic
KATRIN KATRIN
MARE • 187 Re: • E 0 = 2.47 keV, lowest in nature → higher statistics near endpoint • large natural abundance: 62.8% • AgReO 4 crystal bolometry: • Δ E < 30 eV (target: 10 eV) • pileup is problematic → small crystals
MARE • MANU single crystal: m ν < 20 eV • MIBETA 10 detector array: m v < 15 eV • MARE I / MIBETA 2 • 288 element array under construction (taking data now?) • sensitivity to m ν < 2 eV • MARE II • up to 50k elements • sensitivity to m ν < 0.2 eV
Cosmological Limits K. Ichikawa, J. Phys.: Conf. Ser. 120 , 022004 (2008) E. Komatsu et al. , ApJS 180 , 330 (2009) • Robust limit Σ m ν < ~0.6 eV due to thermodynamics of last scattering surface • Can get stronger but less robust limits near Σ m ν < ~0.2 eV by adding constraints from Ly α forest and galaxy clustering data • Stronger limits will require treatment of mass splittings - see arXiv:0907.1917
Double-Beta Decay Experiments
⎞ ｜ ⎠ ⎛ ｜ ⎝ ⎞ ｜ ⎠ ｜ ⎝ ⎛ Majorana Neutrinos ν L m LM (m D ) T L = ½ ( ν Lc ν R ) + h.c. ν Rc m D m RM Two classes of eigen- ν : ν 1 ≈ ( ν L - ν Lc ) + (m D /m RM )( ν R - ν Rc ) m 1 ≈ (m D ) 2 / m RM ν 2 ≈ ( ν R + ν Rc ) + (m D /m RM )( ν L + ν Lc ) m 2 ≈ m RM “Seesaw” mechanism 12
Majorana Neutrinos ν = ν → Lepton number violation → Leptogenesis Matter-Antimatter Asymmetry: Sakharov conditions* • Baryon number violation / baryogenesis • C and CP violation • Interactions out of thermal equilibrium Double-beta decay is currently the only practical method of determining if ν are Majorana particles. * A. D. Sakharov, JETP 5 , 24 (1967). 13
Double-Beta Decay e - e - ν e ν e W - W - > > Nuclear Process (A, Z) (A, Z+2)
Double-Beta Decay e - e - ν e ν e W - W - > > Nuclear Process (A, Z) (A, Z+2) e - e - ν i ν i U ei U ei W - W - T ½ 0 ν = ( G 0 ν | M 0 ν | 2 〈 m ββ 〉 2 ) -1 > > Nuclear Process (A, Z) (A, Z+2) 〈 m ββ 〉 ≡ ⎮ Σ m i U ei2 ⎮
Double-Beta Decay 3 3 10 10 2 2 10 10 [meV] [meV] Inverted 10 10 � � � � � � m m � � Normal 1 1 -1 -1 10 10 3 3 2 2 10 10 10 10 1 1 10 10 Lightest Lightest mass [meV] mass [meV] � �
Claimed Observation Klapdor Kleingrothaus et al ., Mod. Phys. Lett. A 21 (2006) p 1547. 71.7 kg y T 1/2 = (2.23 +0.44 ) x 10 25 y − 0.31 significance ~6 σ 〈 m ββ 〉 < ~0.15-0.6 eV
Double-Beta Decay 3 3 10 10 Claimed signal in 76 Ge: Mod. Phys. Lett. A 21 (2006) p 1547. 2 2 10 10 [meV] [meV] Inverted 10 10 � � � � � � m m � � Normal 1 1 -1 -1 10 10 3 3 2 2 10 10 10 10 1 1 10 10 Lightest Lightest mass [meV] mass [meV] � �
Double-Beta Decay 3 3 10 10 Disfavored by 0 νββ Claimed signal in 76 Ge: Mod. Phys. Lett. A 21 (2006) p 1547. 2 2 10 10 [meV] [meV] Inverted 10 10 � � � � � � m m � � Normal 1 1 -1 -1 10 10 3 3 2 2 10 10 10 10 1 1 10 10 Lightest Lightest mass [meV] mass [meV] � �
Double-Beta Decay 3 3 10 10 Disfavored by 0 νββ Claimed signal in 76 Ge: Mod. Phys. Lett. A 21 (2006) p 1547. 2 2 10 10 [meV] [meV] Inverted Disfavored by cosmology 10 10 � � � � � � m m � � Normal 1 1 -1 -1 10 10 3 3 2 2 10 10 10 10 1 1 10 10 Lightest Lightest mass [meV] mass [meV] � �
Double-Beta Decay 3 3 10 10 Disfavored by 0 νββ Claimed signal in 76 Ge: Mod. Phys. Lett. A 21 (2006) p 1547. 2 2 10 10 [meV] [meV] Inverted Disfavored by cosmology 10 10 � � � � � � m m � � Normal 1 1 -1 -1 10 10 3 3 2 2 10 10 10 10 1 1 10 10 Lightest Lightest mass [meV] mass [meV] � �
Double-Beta Decay 3 3 10 10 Disfavored by 0 νββ Claimed signal in 76 Ge: Mod. Phys. Lett. A 21 (2006) p 1547. 2 2 10 10 [meV] [meV] Inverted Disfavored by cosmology 10 10 � � � � � � m m � � Normal 1 1 -1 -1 10 10 3 3 2 2 10 10 10 10 1 1 10 10 Lightest Lightest mass [meV] mass [meV] � �
Backgrounds 76 Ge 23
Nuclear Matrix Elements 76 Ge 82 Se 100 Mo 128 Te 130 Te 136 Xe 150 Nd 154 Sm Barea and Iachello, Phys. Rev. C 79 , 044301 (2009).
Multiple Measurements V. M. Gehman and S. R. Elliott, J. Phys. G 34 , 667 (2007). • Assumes a single dominant mechanism • Requires NME calculated to 20% • Correlations between NME must be considered (see arXiv:0905.1832 hep-ph)
Source = Detector
M AJORANA and GERDA • enr Ge array submersed in LAr • Modular enr Ge arrays in EFCu • Water cherenkov μ veto cryostats, passive and active shielding • D EMONSTRATOR : 30 kg enriched + • Phase I: ~18 kg (H-M/IGEX xtals) 30 kg natural PPC detectors • Phase II: +20 kg seg. or PPC xtals • Open exchange of knowledge and ideas (e.g. MaGe MC) • Intend to merge for 1-ton experiment using the best techniques See talk by Marino, this session
GERDA • Construction progressing rapidly at LNGS • Phase 1 scheduled to start in early 2010. Sensitivity: 〈 m ββ 〉 < ~200-500 meV • Phase II R&D with highly segmented and “BEGe” detectors. Sensitivity: 〈 m ββ 〉 < ~80-200 meV
CUORE See talk by Ejzak, this session TeO 2 bolometers • 750 kg TeO 2 (200 kg 130 Te) • Starting ~2012 in LNGS; first tower this winter • Sensitivity: 〈 m ββ 〉 < 15-80 meV
See talk by Ejzak, this session CUORICINO 60 Co 18 kg ( 130 Te) y 〈 m ββ 〉 < ~0.2-0.7 meV U/Th surface α / β
See talk by Ackerman, EXO-200 this session • 200 kg of 80% enr Xe • LXe TPC: collect ionization and scintillation for improved resolution • Under construction at WIPP • Sensitivity: 〈 m ββ 〉 < ~100-200 meV
See talk by Ackerman, EXO-200 this session • 200 kg of 80% enr Xe • LXe TPC: collect ionization and scintillation for improved resolution • Under construction at WIPP • Sensitivity: 〈 m ββ 〉 < ~100-200 meV
See talk by Ackerman, this session Full EXO • Tag the Ba final state • Tons of 136 Xe • Sensitivity: 〈 m ββ 〉 < 5-30 meV
EXO-gas / NEXT 0 νββ e -
COBRA • CdZnTe room temp semiconductors • 4 x 4 array of 1 cm 3 crystals at LNGS J.V. Dawson et al. , arXiv:0902.3582
KING COBRA • 40 x 40 x 40 array of coincidence pixelated crystals • Enrich to 90% in 116 Cd • Sensitivity: 〈 m ββ 〉 < 20-100 meV
Scintillator Experiments
SNO+ LAB, 0.1% loaded Sensitivity (nom. NME): with nat Nd → 50 kg 〈 m ββ 〉 < ~100 meV
KamLAND+ • Central 1.4 m radius LS balloon loaded with 200 kg 136 Xe • Sensitivity: 136 Xe + 〈 m ββ 〉 < ~100 meV LS • 136 Xe installation as early as 2011
CANDLES CANDLES II
CANDLES III 地下 • 96 crystals, 305 kg • FutureR&D : 48 Ca enrichment via crown ether
Source ≠ Detector Tracking Detectors
NEMO-3 Segmented Modular thin calorimeter ββ source foil High granularity tracking volume 100 Mo 100 Mo
NEMO-3: 100 Mo 〈 m ββ 〉 < 0.5-1 eV 100 Mo 100 Mo SSD confirmation
SuperNEMO • Modular design • 100 kg 82 Se • Likely in Modane • Demonstrator: 7 kg 82 Se 〈 m ββ 〉 < ~200-500 meV
Other ββ Tracking R&D OPERA MOON DCBA TGV
Other ββ Tracking R&D OPERA MOON � � 10 µ m DCBA TGV
Summary • Kinematic and cosmological tests will explore the quasi-degenerate region in the next ~5 years • Klapdor-Kleingrothaus et al . claimed 0 νββ signal will be tested within several years • Inverted hierarchy within reach for several isotopes in the current / next generation detectors
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