Transcript Double-Beta Decay Valencia - uni

Double Beta Decay
and
Physics beyond the
Standard Model
Amand Faessler
Tuebingen
Accuracy of the Nuclear Matrix Elements.
It determines the Error of the Majorana
Neutrino Mass extracted
Amand Faessler,
München, 24. November
2005
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Oνββ-Decay (forbidden)
P
P
Left
ν
Phase Space
Left
106 x 2νββ
n
n
only for Majorana Neutrinos
ν = νc
Amand Faessler,
München, 24. November
2005
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GRAND UNIFICATION
Left-right Symmetric Models SO(10)
Majorana Mass:
Amand Faessler,
München, 24. November
2005
5
P
P
ν
e-
L/R
n
e-
ν
l/r
n
Amand Faessler,
München, 24. November
2005
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L/R
l/r
P
P
ν
l/r
light ν
heavy N
l/r
Neutrinos
n
n
Amand Faessler,
München, 24. November
2005
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Supersymmetry
Bosons ↔ Fermions
----------------------------------------------------------------------P
P
e-
e-
Proton
Proton
u
u
Neutralinos
u
d
u
d
Neutron
Neutron
n
n
Neutralinos
Amand Faessler,
München, 24. November
2005
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Theoretical Description:
Simkovic, Rodin, Benes, Vogel, Bilenky, Salesh,
Gutsche, Pacearescu, Haug, Kovalenko, Vergados,
Kosmas, Schwieger, Raduta, Kaminski, Stoica,
Suhonen, Civitarese, Tomoda, Valle, Moya de
Guerra, Sarriguren et al.
Never in Tuebingen: Muto/Tokyo, Hirsch/Valencia
0+
k
k
1+
P
P
e1
ν
k
e2
Ek
2n
n
Ei
0+
0+
0νββ
Amand Faessler,
München, 24. November
2005
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Neutrinoless Double BetaDecay Probability
Amand Faessler,
München, 24. November
2005
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Effective Majorana
Neutrino-Mass
for the 0nbb-Decay
Tranformation from Mass
to Flavor Eigenstates
CP
Amand Faessler,
München, 24. November
2005
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Bilenky, Faessler, Simkovic:, Phys.Rev.
D70:033003(2004) : hep-ph/0402250
Amand Faessler,
München, 24. November
2005
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The best choice:
Quasi-Particle-
Pairing
(a)
Quasi-Boson-Approx.:
(b)
Particle Number non-conserv.
(important near closed shells)
Unharmonicities
Proton-Neutron Pairing
(c)
(d)
Amand Faessler,
München, 24. November
2005
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g(A)**4 = 1.25**4 = 2.44 fit to 2nbb
Rodin, Faessler, Simkovic, Vogel, Mar 2005 nucl-th/0503063
Amand Faessler,
München, 24. November
2005
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2.76 (QRPA)
2.34 (RQRPA) Muto corrected
Amand Faessler,
München, 24. November
2005
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M0ν (QRPA)
O. Civitarese, J. Suhonen,
NPA 729 (2003) 867
Nucleus
76Ge
100Mo
130Te
136Xe


their(QRPA, 1.254)
3.33
2.97
3.49
4.64
our(QRPA, 1.25)
2.68(0.12)
1.30(0.10)
1.56(0.47)
0.90(0.20)
g(pp) fitted differently
Higher order terms of nucleon
Current included differently with Gaussian form factors
based on a special quark model ( Kadkhikar, Suhonen,
Faessler, Nucl. Phys. A29(1991)727). Does neglect
pseudoscalar coupling (see eq. (19a)), which is an effect of
30%.
We: Higher order currents from Towner and Hardy.

What is the basis and the dependence on the size of the
basis?

Short-range Brueckner Correlations not included. But
finite size effects included.

We hope to understand the differences. But for that we
need to know their input parameters ( g(pp), g(ph),basis,
…)!
Amand Faessler,
München, 24. November
2005
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Uncorrelated and Correlated
Relative N-N-Wavefunction
in the N-N-Potential
Short Range Correlations
Amand Faessler,
München, 24. November
2005
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Influence of Short Range
Correlations
(Parameters from Miller and Spencer, Ann. Phys 1976)
Amand Faessler,
München, 24. November
2005
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Comparison of 2nbb
Half Lives with Shell model
Results from Strassburg
Amand Faessler,
München, 24. November
2005
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Neutrinoless Double Beta Decay and the
Sensitivity to the Neutrino Mass
of planed Experiments
expt.
T1/2
[y]
<mv>
[eV]
1.2 X 1024
2.3
MAJORANA
(76Ge)
3 X 1027
0.044
EXO 10t
(136Xe)
4 X 1028
0.012
GEM (76Ge)
7 X 1027
0.028
GERDA II
(76Ge)
2 X 1026
0.11
CANDLES
(48Ca)
1 X 1026
0.2
MOON
(100Mo)
1 X 1027
0.058
DAMA
(136Xe)
Amand Faessler,
München, 24. November
2005
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Neutrinoless Double Beta Decay and the
Sensitivity to the Neutrino Mass
of planed Experiments
expt.
T1/2
[y]
<mv>
[eV]
XMASS
(136Xe)
3 X 1026
0.10
CUORE
(130Te)
2 X 1026
0.10
COBRA
(116Cd)
1 X 1024
1
DCBA
(100Mo)
2 X 1026
0.07
DCBA (82Se)
3 X 1026
0.04
CAMEO
(116Cd)
1 X 1027
0.02
DCBA
(150Nd)
1 X 1026
0.02
Amand Faessler,
München, 24. November
2005
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Summary:
Accuracy of Neutrino Masses
from 0nbb


Fit the g(pp) by 2nbb in front of the particleparticle NN matrixelement include exp. Error of
2nbb.
Calculate with these g(pp) for three different
forces (Bonn, Nijmegen, Argonne) and three
different basis sets (small about 2 shells,
intermediate 3 shells and large 5 shells) the
0nbb.

Use QRPA and R-QRPA (Pauli principle)

Use: g(A) = 1.25 and 1.00


Error of matrixelement 20 to 40 % (96Zr
larger; largest errors from experim. values of
T(1/2, 2nbb)).
Core overlap reduction by ~0.90 (preliminary)
Amand Faessler,
München, 24. November
2005
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Summary:
Results from 0nbb

Klapdor et al. from 0nbb Ge76 with R-QRPA (no
error of theory included): 0.15 to 0.72 [eV].

<m(n)>(0nbb Ge76, Exp. Klapdor) < 0.47 [eV]
<M(heavy n)> > 1.2 [GeV]

<M(heavy Vector B)> > 5600 [GeV]

SUSY+R-Parity: l‘(1,1,1) < 1.1*10**(-4)

Mainz-Troisk, Triton Decay: m(n) < 2.2 [eV]

Astro Physics (SDSS): Sum{ m(n) } < ~0.5 to 2
[eV]

Do not take democratic
averaged matrix elements !!!
Amand Faessler,
München, 24. November
2005
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Open Problems:
1. Overlapping but slightly different
Hilbert spaces in intermediate Nucleus
for QRPA from intial and from final
nucleus.
0+
pn-1
1+
β-
2-
np-1
0+
0+
2. Pairing does not conserve Nucleon
number. Problem at closed shells.
Particle projection.
Lipkin-Nogami <N>, <N2>
3. Deformed nuclei? (e.g.:
THE END
Amand Faessler,
München, 24. November
2005
150Nd
)
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