Comments on Neutrinoless Double Beta Decay Experiments

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Comments on Neutrinoless Double Beta Decay
Experiments

• Huan Zhong Huang (???)
• Department of Physics and Astronomy
• University of California, Los Angeles 90095
• huang_at_physics.ucla.edu
• OCPA Underground Sciences Workshop
• Hong Kong, July 21-23 2008
• Thanks to F. Avignone, S.J. Freedman,
• E. Fiorini, R. Maruyama

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Neutrino Physics Program
Critical Questions for Future Neutrino Physics
Program 1) Are neutrinos their own
anti-particles? Dirac or Majorana
neutrinos 2) What are the scale of neutrino
masses and the hierarchy of the neutrino mass
ordering? 3) What is the remaining neutrino
mixing angle q13? 4) Do neutrinos violate the
CP symmetry and contribute to the
matter-antimatter asymmetry?
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Massive Neutrinos Majorana or Dirac?
Lorentz Invariance massive particle velocity
lt speed of light c
spin
Left-handed nLH
Momentum
(Lab)
Right-handed nRH
(Speed-of-light Frame)
Majorana Neutrino Neutrinoanti-neutrino
Dirac Neutrino Neutrino and anti-neut distinct
Boost
Boost
nLH
nRH
CPT
CPT
CPT
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Double Beta Decay
2???
2nbb T1/2 1018y
1935
M. Goeppert-Mayer
(A,Z) ? (A,Z2) 2e 2?ne
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Dirac or Majorana Neutrinos?
0???
1937
Majorana ? neutrino anti-neutrino Lepton Number
violation !
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Measuring Neutrino Masses

• Direct Measurement
• tritium decays
• E0 18.6 keV
• ltmbgt

2) Effective Majorana Mass ltmbbgt
ei CP phase for neutrinos
3) Precise Cosmological Measurement ltmSgt

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The actual range of mbb depends on the NME
! There is no clear issue identified regarding
the experimental data.
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The Cuoricino experiment

• 62 TeO2 bolometers
• Total detector mass
• M 11 kg 130Te 5x1025 130Te nuclides
• Deep underground in the Gran Sasso Laboratory
  (Italy) (3500 m.w.e.)
• Started in 2003, currently the largest operated
  bolometric experiment

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Cuoricino Results Neither Support Nor Rule Out
Heidelberg-Moscow Claim
Background in bb region 0.18 ? 0.01
c/keV/kg/y Average resolution _at_ 2615keV 8keV
Results for 0nbb half life and Majorana mass (90
c.l.) T1/20n (130Te) gt 3.1 x 1024 y mbb lt
200 - 680 meV () () using NME from Rodin et
al, Nucl. Phys. A 776 (2006) and erratum
arXivnucl-th/0706.4304
Cuoricino demonstrates the feasibility of a large
scale bolometric detector with good energy
resolution Background reduction is being worked
on for scaled up CUORE
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The Constraint from Cosmology Competitive
Model Dependent ! G.L. Fogli et al,
hep-ph/0805.2517 Cosmological Data Set S (at
2s) CMB lt 1.19 eV CMBHSTSN-Ia lt 0.75
eV CMBHSTSN-IaBAO lt 0.60 eV
CMBHSTSN-IaBAOLya lt 0.19 eV
CMB WMAP 5-year, ACBAR, VSA, CBI, BOOMERANG HST
Hubble Space Telescope h0.75-0.07 SN-Ia
SNLA (The SuperNova Legacy Survey) BAO Baryonic
Acoustic Oscillation (WMAP) Lya Small Scale
Primordial Spec from Lyman-a forest coulds
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Candidate for Double beta Decays
Q (MeV) Abund.()
48Ca?48Ti 4.271 0.187
76Ge??76Se 2.040 7.8
82Se?82Kr 2.995 9.2
96Zr?96Mo 3.350 2.8
100Mo?100Ru 3.034 9.6
110Pd?110Cd 2.013 11.8
116Cd?116Sn 2.802 7.5
124Sn?124Te 2.228 5.64
130Te?130Xe 2.533 34.5
136Xe?136Ba 2.479 8.9
150Nd?150Sm 3.367 5.6
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Major 0nbb Experiments(scalable to 1 ton now or
planned)
0nbb Experiments -- CUORE 130Te --
MAJORANA/GERDA 76Ge -- EXO 136Xe Essential to
Measure 0nbb for Several Elements !!
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US-Italy Collaboration CUORE _at_ LNGS
CUORE RD (Hall C)
Underground National Laboratory of Gran
Sasso L'Aquila ITALY 3500 m.w.e.
CUORICINO - CUORE (Hall A)
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CUORE
CUORE Cryogenic Underground Observatory for Rare
Events will be a tightly packed array of 988
Bolometers - M 200 kg of 130Te
80 cm

• Operated at Gran Sasso laboratory
• Special cryostat built w/ selected materials
• Cryogen-free dilution refrigerator
• Shielded by several lead shields

19 CUORICINO-like towers with 13 planes of 4
crystals each
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Bolometer
TeO2 Bolometer Source Detector
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Signal from NTD Ge Thermistor
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Energy resolution of a TeO2 crystal of 5x5x5
cm3 ( 760 g )
0.8 keV FWHM _at_ 46 keV 1.4 keV FWHM _at_ 0.351
MeV 2.1 keV FWHM _at_ 0.911 MeV 2.6 keV FWHM _at_
2.615 MeV 3.2 keV FWHM _at_ 5.407 MeV the best a
spectrometer so far
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Scaling CUORE from CUORICINO
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Background Reduction is the Key
CUORICINO Surface Related Background CUORE --
Crystal Production -- TeO2 Material QA for
Crystal Production -- Crystal Processing QA
-- Improved Surface Cleaning Procedure Crystal
Support Structure (Cu) -- New/Improved Surface
Cleaning Procedure Note CUORICINO/CUORE Has
Excellent Shielding (Roman Lead)
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Expected Sensitivity of the CUORE Experiment
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General Comments
CUORE-- 130Te -- Excellent Energy Resolution
(FWHM 0.3) -- Cost Effective -- Background
Elimination Challenging -- Data-Taking Early
2011 GERDA/MAJORANA -- 76Ge -- Ultra-Low
Background Possible -- Detector Segmentation and
Pulse Shape Analysis Possible -- Very Costly
! EXO -- 136Xe -- Easy to Scale Up -- Ba
Tagging Challenging / FWHM 3.4
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Interdisciplinary Sciences
Three Overarching Themes -- APS multidivisional
neutrino study Neutrino Matrix
physics/0411216

• Neutrinos and the New Paradigm
• -- neutrino masses, Dirac/Majorana and CP
  violation
• beyond the Standard Model
• 2) Neutrinos and the Unexpected
• -- Many discoveries in recent years, what
  surprises and
• extraordinary properties ahead?
• 3) Neutrinos and Cosmos
• -- of neutrinos, neutrino masses large
  structures
• CP violation matter/anti-matter asymmetry

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CUORE Collaboration
Universita di Milano-Bicocca5 C. Arnaboldi, C.
Brofferio, S. Capelli, M. Carrettoni, M.
Clemenza, E. Fiorini, S. Kraft, C. Maiano, C.
Nones, A. Nucciotti, M. Pavan, D. Schaeffer, M.
Sisti, L. Zanotti Sezione di Milano
dellINFN F. Alessandria, L. Carbone, O.
Cremonesi, L. Gironi, G. Pessina, S. Pirro, E.
Previtali Politecnico di Milano R. Ardito, G.
Maier Laboratori Nazionali del Gran Sasso M.
Balata, C. Bucci, P. Gorla, S. Nisi, E. L.
Tatananni, C. Tomei, C. Zarra Universita di
Firenze and Sezione di Firenze dellINFN M.
Barucci, L. Risegari, G. Ventura Universita
dellInsubria5 E. Andreotti, L. Foggetta, A.
Giuliani, M. Pedretti, C. Salvioni Universita di
Genova S. Didomizio6, A. Giachero7, P.
Ottonello6, M. Pallavicini6 Laboratori
Nazionali di Legnaro G. Keppel, P. Menegatti, V.
Palmieri, V. Rampazzo Universita di Roma La
Sapienza and Sezione di Roma dellINFN F.
Bellini, C. Cosmelli, I. Dafinei, R. Faccini, F.
Ferroni, C. Gargiulo, E. Longo, S. Morganti, M.
Olcese, M. Vignati Universita di Bologna and
Sezione di Bologna dellINFN M. M. Deninno, N.
Moggi, F. Rimondi, S. Zucchelli University of
Zaragoza M. Martinez Kammerling Onnes
Laboratory, Leiden University A. de Waard, G.
Frossati Shanghai Institute of Applied Physics
(Chinese Academy of Sciences) X. Cai, D. Fang,
Y. Ma, W. Tian, H. Wang 5also Sezione di Milano
dellINFN 6also Sezione di Genova dellINFN 7also
LNGS
University of California at Berkeley A. Bryant2,
M.P. Decowski2 , M.J. Dolinski3 , S.J. Freedman2,
E.E. Haller2, L. Kogler2, Yu.G.
Kolomensky2 University of South Carolina F.T.
Avignone III, I. Bandac, R. J. Creswick, H.A.
Farach, C. Martinez, L. Mizouni, C. Rosenfeld
Lawrence Berkeley National Laboratory J.
Beeman, E. Guardincerri, R.W. Kadel, A.R. Smith,
N. Xu Lawrence Livermore National Laboratory K.
Kazkaz, E.B. Norman4, N. Scielzo University of
California, Los Angeles H. Z. Huang, S.
Trentalange, C. Whitten Jr. University of
Wisconsin, Madison L.M. Ejzak, K.M. Heeger, R.H.
Maruyama, S. Sangiorgio California Polytechnic
State University T.D. Gutierrez 2also
LBNL 3also LLNL 4also UC Berkeley
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Full estimated range of M0n within QRPA framework
and comparison with NSM
(higher order currents now included in NSM) P.
Vogel
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Double Beta Decay Candidates
Normal beta-decay is energetically forbidden,
while double beta-decay from (A,Z) ? (A, Z2)
is energetically allowed
(Aeven, Zeven)
A, Z1
A, Z3
0
A, Z
bb
0
A, Z2
Some candidates
48Ca, 70Zn, 76Ge, 80Se, 86Kr, 96Zr, 100Mo, 116Cd,
130Te, 136Xe, 150Nd
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CUORE

• Array of 988 TeO2 crystals
• 19 Cuoricino-like towers
• 13 levels, 4 crystals each
• 5x5x5 cm3 (750 g each)
• Low conductance Teflon insulators
• OFHC Cu structure
• Crystals equipped with NTDs
• Suspended from cold stage
• Mechanically isolated

OGHC-Oxygen Free High Conductivity NTD-Neutron
Transmutation Doped
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Neutrino Masses and Hierarchy
Normal
Inverted
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Cosmogenic Co from Te