Non-Oscillation Neutrino Physics Jason Detwiler Lawrence Berkeley - - PowerPoint PPT Presentation

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?
• What are the precise
• scillation parameters?
• Is θ13 > 0?
• Is CP violated in the ν

sector?

• Do sterile ν exist?
• What can ν tell us about

the sun, Earth, SN, CνB, ...

From presentation by S. King at UKNF (Dec 2005), available at http://hepunx.rl.ac.uk/uknf/2005-05-04/uknf-sfk-pheno.ppt

Normal Inverted

Kinematic and Cosmological Experiments

Kinematic Measurements

tritium experiments

KATRIN

10-11 mbar

• 18.574 kV

Precise energy selection

• f electrons

1 e- /s e- Monitor source parameters

3He

10-11 mbar

• 18.4 kV

103 e- /s e- Reject low-energy electrons 1010 e- /s Transport electrons recycle tritium

3He

1010 e- /s

3H 3He

e-

3•10-3 mbar ±1 kV

• decay

e

• Provide stable

tritium column density

Rear Source Trans/pump Pre-spectrometer Main spectrometer Detector

e-

B = 3 T B = 6 T (0.3 mT)

1.7 x 1011 Bq

70 m ΔE = Bmin/Bmax x 18.6 keV = 93 eV → mν < 200 meV

Si pin diode

Neutrino Mass Scale

kinematic

KATRIN

KATRIN

• 187Re:
• E0 = 2.47 keV, lowest in nature

→higher statistics near endpoint

• large natural abundance: 62.8%
• AgReO4 crystal bolometry:
• ΔE < 30 eV (target: 10 eV)
• pileup is problematic → small

crystals

MARE

• MANU single crystal: mν < 20 eV
• MIBETA 10 detector array:

mv < 15 eV

• MARE I / MIBETA 2
• 288 element array under

construction (taking data now?)

• sensitivity to mν < 2 eV
• MARE II
• up to 50k elements
• sensitivity to mν < 0.2 eV

MARE

Cosmological Limits

• K. Ichikawa, J. Phys.: Conf. Ser. 120, 022004 (2008)
• E. Komatsu et al., ApJS 180, 330 (2009)
• Robust limit Σmν < ~0.6 eV due to thermodynamics of last scattering surface
• Can get stronger but less robust limits near Σmν < ~0.2 eV by adding

constraints from Lyα forest and galaxy clustering data

• Stronger limits will require treatment of mass splittings - see arXiv:0907.1917

Double-Beta Decay Experiments

Majorana Neutrinos

νL νRc ⎛ ｜ ⎝ ⎞ ｜ ⎠ mLM mD ⎛ ｜ ⎝ ⎞ ｜ ⎠ (mD)T mRM

L = ½ ( νLc νR )

+ h.c. Two classes of eigen-ν: ν1 ≈ (νL - νLc) + (mD/mRM)(νR - νRc) ν2 ≈ (νR + νRc) + (mD/mRM)(νL + νLc) m1 ≈ (mD)2 / mRM m2 ≈ mRM

“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

* A. D. Sakharov, JETP 5, 24 (1967).

Double-beta decay is currently the only practical method of determining if ν are Majorana particles.

13

Double-Beta Decay

> >

Nuclear Process

(A, Z) (A, Z+2) W- W- e- e- νe νe

Double-Beta Decay

T½0ν = ( G0ν |M0ν|2 〈mββ〉2 )-1 〈mββ〉 ≡ ⎮Σ mi Uei2⎮

> >

Nuclear Process

(A, Z) (A, Z+2) W- W- e- e- νe νe

> >

Nuclear Process

(A, Z) (A, Z+2) W- W- e- e- νi νi Uei Uei

mass [meV]

• Lightest

1 10

2

10

3

10 [meV]

• m
• 1

10 1 10

2

10

3

10 mass [meV]

• Lightest

1 10

2

10

3

10 [meV]

• m
• 1

10 1 10

2

10

3

10 Inverted Normal

Double-Beta Decay

Claimed Observation

71.7 kg y T1/2 = (2.23+0.44) x 1025 y significance ~6σ

−0.31 Klapdor Kleingrothaus et al., Mod. Phys. Lett. A 21 (2006) p 1547.

〈mββ〉< ~0.15-0.6 eV

mass [meV]

• Lightest

1 10

2

10

3

10 [meV]

• m
• 1

10 1 10

2

10

3

10 mass [meV]

• Lightest

1 10

2

10

3

10 [meV]

• m
• 1

10 1 10

2

10

3

10 Inverted Normal

Double-Beta Decay

Claimed signal in 76Ge: Mod. Phys. Lett. A 21 (2006) p 1547.

mass [meV]

• Lightest

1 10

2

10

3

10 [meV]

• m
• 1

10 1 10

2

10

3

10 mass [meV]

• Lightest

1 10

2

10

3

10 [meV]

• m
• 1

10 1 10

2

10

3

10 Inverted Normal

Double-Beta Decay

Disfavored by 0νββ Claimed signal in 76Ge: Mod. Phys. Lett. A 21 (2006) p 1547.

mass [meV]

• Lightest

1 10

2

10

3

10 [meV]

• m
• 1

10 1 10

2

10

3

10 mass [meV]

• Lightest

1 10

2

10

3

10 [meV]

• m
• 1

10 1 10

2

10

3

10 Inverted Normal

Double-Beta Decay

Disfavored by cosmology Disfavored by 0νββ Claimed signal in 76Ge: Mod. Phys. Lett. A 21 (2006) p 1547.

mass [meV]

• Lightest

1 10

2

10

3

10 [meV]

• m
• 1

10 1 10

2

10

3

10 mass [meV]

• Lightest

1 10

2

10

3

10 [meV]

• m
• 1

10 1 10

2

10

3

10 Inverted Normal

Double-Beta Decay

Disfavored by cosmology Disfavored by 0νββ Claimed signal in 76Ge: Mod. Phys. Lett. A 21 (2006) p 1547.

mass [meV]

• Lightest

1 10

2

10

3

10 [meV]

• m
• 1

10 1 10

2

10

3

10 mass [meV]

• Lightest

1 10

2

10

3

10 [meV]

• m
• 1

10 1 10

2

10

3

10 Inverted Normal

Double-Beta Decay

Disfavored by cosmology Disfavored by 0νββ Claimed signal in 76Ge: Mod. Phys. Lett. A 21 (2006) p 1547.

Backgrounds

23

76Ge

Nuclear Matrix Elements

Barea and Iachello, Phys. Rev. C 79, 044301 (2009).

76Ge 82Se 100Mo 128Te 130Te 136Xe 150Nd 154Sm

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

MAJORANA and GERDA

• enrGe array submersed in LAr
• Water cherenkov μ veto
• Phase I: ~18 kg (H-M/IGEX xtals)
• Phase II: +20 kg seg. or PPC xtals
• Modular enrGe arrays in EFCu

cryostats, passive and active shielding

• DEMONSTRATOR: 30 kg enriched +

30 kg natural PPC detectors

• 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:

• Phase II R&D with highly

segmented and “BEGe”

• detectors. Sensitivity:

〈mββ〉< ~200-500 meV 〈mββ〉< ~80-200 meV

CUORE

• 750 kg TeO2 (200 kg 130Te)
• Starting ~2012 in LNGS;

first tower this winter

• Sensitivity:

TeO2 bolometers

〈mββ〉< 15-80 meV

See talk by Ejzak, this session

CUORICINO

〈mββ〉< ~0.2-0.7 meV 18 kg (130Te) y

60Co

U/Th surface α/β See talk by Ejzak, this session

• 200 kg of 80% enrXe
• LXe TPC: collect

ionization and scintillation for improved resolution

• Under construction

at WIPP

• Sensitivity:

EXO-200

〈mββ〉< ~100-200 meV

See talk by Ackerman, this session

• 200 kg of 80% enrXe
• LXe TPC: collect

ionization and scintillation for improved resolution

• Under construction

at WIPP

• Sensitivity:

EXO-200

〈mββ〉< ~100-200 meV

See talk by Ackerman, this session

Full EXO

• Tag the Ba final state
• Tons of 136Xe
• Sensitivity:

〈mββ〉< 5-30 meV

See talk by Ackerman, this session

EXO-gas / NEXT

0νββ e-

COBRA

• CdZnTe room temp

semiconductors

• 4 x 4 array of 1 cm3

crystals at LNGS

J.V. Dawson et al., arXiv:0902.3582

KING COBRA

• 40 x 40 x 40 array of

pixelated crystals

• Enrich to 90% in 116Cd
• Sensitivity:

〈mββ〉< 20-100 meV

coincidence

Scintillator Experiments

SNO+

LAB, 0.1% loaded with natNd → 50 kg

Sensitivity (nom. NME): 〈mββ〉< ~100 meV

KamLAND+

• Central 1.4 m radius

LS balloon loaded with 200 kg 136Xe

• Sensitivity:
• 136Xe installation as

early as 2011 〈mββ〉< ~100 meV

136Xe

+ LS

CANDLES

CANDLES II

CANDLES III 地下

• 96 crystals, 305 kg
• FutureR&D : 48Ca

enrichment via crown ether

Source ≠ Detector Tracking Detectors

Modular thin ββ source foil High granularity tracking volume Segmented calorimeter

NEMO-3

100Mo 100Mo

NEMO-3: 100Mo

100Mo

SSD confirmation

100Mo

〈mββ〉< 0.5-1 eV

SuperNEMO

• Modular design
• 100 kg 82Se
• Likely in Modane
• Demonstrator: 7 kg 82Se

〈mββ〉< ~200-500 meV

Other ββ Tracking R&D

MOON TGV DCBA OPERA

Other ββ Tracking R&D

TGV MOON DCBA OPERA

10µm

Summary

• Kinematic and cosmological tests will

explore the quasi-degenerate region in the next ~5 years

• Klapdor-Kleingrothaus et al. claimed 0νββ

signal will be tested within several years

• Inverted hierarchy within reach for several

isotopes in the current / next generation detectors