Neutrinos Theory

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Neutrinos Theory

• Carlos Pena Garay
• IAS, Princeton

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1 kton water Gd guided by KamLAND

KamLAND 1kton LS, 2000 PMT, 33 cov (1.4 yr,
90) Supernova (8.5 kpc) 300 events Relic
Supernova (Egt6MeV) 0.4 events/yr
bck React Geon Bin1
125.2 (24.6) 2.3 6.3 Bin2
24.6 (19.8) 19.5
7.4 Bin3 12.9 ( 9.8) 35.1
3.9 Bin4 5.9 ( 3.9)
36.1 2.8
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1 kton water Gd guided by KamLAND

Gd-1kton, 2000 PMT, 33 cov (1.4 yr, 90)
Supernova (8.5 kpc) 300 events Relic
Supernova (Egt5MeV) 0.5 events/yr
bck React Geon Bin1
125.2 (24.6) 0 7 Bin2
24.6 (19.8) 1
8.5 Bin3 12.9 ( 9.8) 2
4.5 Bin4 5.9 ( 3.9)
2 3
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Neutrino mass Direct methods
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Plan

• I. Neutrinos as Dirac Particles
• Making Neutrinos
• Neutrinos as Majorana Particles

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Massive Neutrinos Dirac
n(p,h)
n(p,-h)
CPT
Boost, if m ? 0
Boost, if m ? 0
n(p,-h)
n(p,h)
CPT
Chirality vs Helicity
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Massive Neutrinos Majorana
n(p,h)
n(p,-h)
CPT
Boost, if m ? 0
Boost, if m ? 0
n(p,-h)
n(p,h)
CPT
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Massive Neutrinos Majorana
n(p,h)
n(p,-h)
CPT
Boost, if m ? 0
Boost, if m ? 0
n(p,-h)
n(p,h)
CPT
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Parameters Majorana

Majorana phases only relevant in processes
involving Lepton Number Violation (na -
nb) Previous discussion on neutrino osc. is valid
for Majorana ! Helicity suppressed by smallness
of neutrino masses
-
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Majorana vs Dirac 0nbb decay
searching
observed
0nbb nn ? ppee (without
neutrinos)
me ltmneegt

(T1/2 FN )1/2 FN G0n M0nf
(gA/ gV)2 M0nGT 2
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Connection with neutrino parameters
j
ltmneegt S mj Uej2 S mj Uej
2 eif
Normal Hierarchy Inverted Hierarchy Degenerate
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From Osc. Data

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Signal Energy Resolution required

Summed electron energy in units of the kinematic
endpoint (Q)
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nuclear matrix elements?

Nuclear Physics methods QRPA, SMNext
Generation experiments
Observed Neutrinos are Majorana
Not observed Hard to extract neutrino
parameters, and exclude Dirac.
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Positive signal ?
Klapdor et al (part of HM) 28.8 (6.9) -gt
3-4s Bckg 60 ev.
0nbb
214Bi
214Bi
?
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Present Limits

Candidate Detector Present
ltmgt (eV) nucleus type (kg
yr) T1/20?ßß (yr) 48Ca
gt9.51021 (76CL) 76Ge Ge
diode 30 gt1.91025 (90CL)
lt0.390.17-0.28 82Se
gt9.51021 (90CL) 100Mo
gt5.51022 (90CL) 116Cd
gt7.01022 (90CL) 128Te
TeO2 cryo 3 gt1.11023 (90CL) 130Te
TeO2 cryo 3 gt2.11023 (90CL)
lt1.1 - 2.6 136Xe Xe scint 10
gt1.21024 (90CL) lt2.9 150Nd
gt1.21021 (90CL) 160Gd
gt1.31021 (90CL)
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Projected/proposed

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Theorem 0nbb ?? Majorana
in gauge theories with SSB
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Seesaw mechanism

Integrating out the heavy field nR mRgtgt ltfgt
Equivalenly, diagonalize the mass matrix in nL-nR
basis
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Leptogenesis

Generate L asymmetry from direct CP violation in
right handed decay Net effect (2 families
needed) Convert L into B via anomaly
-gt Matter- Antimatter asymmetry

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Summary

• Neutrinos oscillate, refract, decohere,
• -gt test sources and explore mixing matrix
• The field is open with a well defined program
• - Complete the mixing matrix q13 and dCP
• 0nbb Dirac vs Majorana
• Test sources (Solar luminosity with neutrinos,)
• Expand to discovery regions
• Low energies solar, ( s. DM searches),
  terrestrial, SN,
• High energies hadronic acceleration sources, CR
  connection
• Be ready for
  surprises