Claudia Nones

Physics of Massive Neutrinos - Blaubeuren, July 1 - 5, 2007

Status of Cuoricino and CUOREwith some remarks on nuclear matrix elements

Centre de Spectrométrie Nucléaire etde Spectrométrie de Masse - Orsay

Brief remarks on the bolometric technique and the choice of 130Te as source of the 0vDBD

Cuoricino experiment: the detector and the updated results

CUORE project

Outline of the talk

Cuoricino vs HM ; 130Te vs other isotopes: comparisons through different N.M.E. calculations seen by the eyes of an experimentalist

Conclusions

deposited energy

heat sink

thermal couplingabsorber crystal

temperature sensor

Bolometric technique:

Main advantages:Main advantages:- high energy high energy resolutionresolution- wide flexibility (few wide flexibility (few constraints on constraints on absorber material)absorber material)- the detector is fully the detector is fully sensitive (no dead sensitive (no dead layer)layer)(also a drawback)(also a drawback)

From a very simple thermal model

-> to develop high pulses the detector has to work at low temperature (10mk)

Signal:∆T = E/C

Brief remarks

WHY WHY 130130Te ?Te ?

• high natural isotopic abundance (33.87 %)

• high transition energy (Q=2530.30 ± 1.99 keV)

- this means large phase space for the decay- the Q-value is important with respect to the natural radioactive background

• encouraging theoretical calculations for 0vDBD lifetime

Cuoricino and CUORE Location

Cuoricino experiment is installed in

Underground National Laboratory of Gran Sasso

L'Aquila – ITALY

the mountain providing a 3500 m.w.e. shield against cosmic rays

R&D final tests for CUORE (hall C)

CUORE (hall A)

Cuoricino(hall A)

It is a self-consistent experiment giving significant results on Double Beta Decay.

The Cuoricino detector

Total number of detectors: 62

total active mass

TeO2 : 40.7 kg

130Te : 11.3 kg

128Te : 10.5 kg

The Cuoricino detector

Neutrinoless DBD results (1)

Background sum spectrum of all the detectors in the DBD region

60Copile up

Energy (keV)

Cou

nts

130Te0vBB

MT = 11.83 kg 130Te y

UPDATED RESULTS:

T1/20v (y) > 3 1024

y mee< 0.2 – 0.98 eV

Bkg = 0.18±0.02 c/keV/kg/y

Neutrinoless DBD results (2)

Are we now able to scrutinize the HM claim of evidence?

… we will see in the last part of the talk!!!

MT = 11.83 kg 130Te y

FWHM measured on sum bkg spectrum @ 2.6

MeV ~ 7 keV

Cryogenic Underground Observatory for Rare Events

CUORE

CUORE status

Funded by the US

For the moment,

we are not late with respect to the master plan

Data taking foreseen in 2011

“PER ME SI VA NE LA CITTA’ DOLENTE,      PER ME SI VA NE L’ETERNO DOLORE,

     PER ME SI VA TRA LA PERDUTA GENTE.  GIUSTIZIA MOSSE IL MIO ALTO FATTORE:

     FECEMI LA DIVINA POTESTATE,      LA SOMMA SAPIENZA E ‘L PRIMO AMORE.

 DINANZI A ME NON FUR COSE CREATE

     SE NON ETERNE, E IO ETERNA DURO.

     LASCIATE OGNI SPERANZA, VOI CH’ENTRATE.”   (Inferno, Canto III, vv. 1-9)

« THROUGH ME THE WAY TO THE CITY OF WOE,THROUGH ME THE WAY INTO ETERNAL PAIN,

THROUGH ME THE WAY AMONG THE LOST.JUSTICE MOVED MY MAKER ON HIGH.

DIVINE POWER MADE ME,

WISDOM SUPREME, AND PRIMAL LOVE.BEFORE ME NOTHING WAS

BUT THINGS ETERNAL,AND I ENDURE ETERNALLY.

ABANDON ALL HOPE, YOU WHO ENTER HERE. »

The world of the Nuclear Matrix Elements through the eyes of an experimentalist

Thanks to A. Poves, V. Rodin and

J. Suhonen for th

eir help…in this

hell!!!

QRPA or not QRPA?…this is the question!!!

QRPA

Shell Model

J. Suhonen – O. Civitarese and the Jyväskylä group

A. Faessler and the Tuebingen group

Prof. Faessler’s advice:

« Do not take democratic averaged matrix elements »

… but so what can we do with our value of T0v

1/2? to evaluate mv

to scrutinize the HM result

to compare next generation experiments

E. Caurier, F. Nowacki, A. Poves, et al.

Cuoricino prospects

Are we able now to scrutinize the HM claim of evidence?

T1/20v (y) = (0.69-4.18) 1025 (3σ range)

mee= 0.24 – 0.58 eV (3σ range)

HM experimental results:

REF. Klapdor et al., Physics Letters B 586 (2004) 198-212Best value: 1.19x1025 y

What I have done…

T1/20v

(Klapdor)T1/2

0v (130Te)Choose a nuclear model

2

0

)(

0

)(0

0

02/11300

2/1

76

130

76

130

)()(

v

GerefA

v

TerefAv

Ge

v

Te

vv

M

M

G

G

KlapdorTTeT

Nuclear matrix element of Muto-Bender-Klapdor

References

Tuebingen’s group: erratum of nucl-th/0503063

Suhonen’s group: nucl-th/0208005

Shell Model: Poves’ talk @ 4th ILIAS Annual Meeting - Chambery

0

1

2

3

4

0 2 4 6 8 10 12

T1/2 x 1024 y for 130Te

Nu

cle

ar

mod

els

Jyväskylä group

Shell model group

Tuebingen group

N.B.: No univoque definition of G0v and M0v!!!

Cuoricino limit vs Klapdor’s claim of evidence

3x1024 y 6x1024 yFinal sensitivity

The main goal of CUORE is to test the inverted hierarchy

213 mmm meVmee )5019(

And what about CUORE? (1)

b

TM

A

aF ~0

b

TM

A

aF ~0

a: isotopic abundance

A: atomic mass

ε: efficiency

M: active mass [kg]

T: live time [y]

b: background [c/keV/kg/y]

Γ: energy resolution [keV]

CUORE_conservative

b=0.01 – Γ=5 – T=5y

CUORE_aggressive

b=0.001 – Γ=5 – T=5y

F0v = 2.1 x 1026 y (1σ)

F0v = 6.6 x 1026 y (1σ)

And what about CUORE? (2)

CUORE and the inverted hierarchy

0

1

2

3

4

0 5 10 15 20 25 30 35

T1/2 x 1026 y for 130Te

Nu

cle

ar

mod

els

CUORE_conservative

CUORE_aggressive

Tuebingen group

Shell Model group

Jyväskylä group

0

1

2

3

4

0 10 1000

Summarizing

Tuebingen group

Shell Model group

Jyväskylä group

Cuoricino

CUORE_conservative CUORE_aggressive

T1/2 x 1024 y for 130Te

Isotope Q_value (keV)Isotopic

abundance (%)

48Ca 4271 0.003576Ge 2039 9.282Se 2995 9.2

100Mo 3034 9.6116Cd 2802 7.5130Te 2530 33.8136Xe 2479 8.9

What about 130Te compared with other isotopes?

a) I fix the range of the mass -> inverted hierarchy (19-50 meV)

b) I use the 3 main “schools of thoughts” in terms of N.M.E.

c) I compare the capability to explore the inverted hierarchy region

ReferencesTuebingen’s group: erratum of nucl-th/0503063

Suhonen’s group: nucl-th/0208005

Shell Model: Poves’ talk @ 4th ILIAS Annual Meeting - Chambery

RQRPA (erratum) – Tuebingen group

0

1

2

3

4

5

6

7

8

0 1 10 100 1000

T1/2 x 1026 y

150Nd

130Te

116Cd

76Ge

136Xe

82Se

100Mo

G0v calculates with gA=1.25 and r0=1.1fm

QRPA – Suhonen’s group

G0v calculates with gA=1.25 and r0=1.2fm

0

1

2

3

4

5

6

7

1 10 100 1000

T1/2 x 1026 y

130Te

116Cd

76Ge

136Xe

100Mo

82Se

Shell Model group

G0v calculates with gA=1.25 and r0=1.2fm

0

1

2

3

4

5

6

1 10 100 1000

T1/2 x 1026 y

130Te

116Cd

76Ge

136Xe

82Se

Conclusions

Cuoricino is presently the most sensitive 0νDBD running experiment, capable to confirm the KK-HM “evidence”.

Cuoricino demonstrates the feasibility of a large scale bolometric detector (CUORE) with good energy resolution and bkg on many detectors.

CUORE, a second generation detector, will be built and start up in the next 4 years.

Recent results on background suppression confirm the capability to attack the inverted hierarchy mass region.

Isotope G0v (gA=1.25 r0=1.2fm)

G0v (gA=1.25 r0=1.1fm)

76Ge 6.31x10-15 7.92x10-15

82Se 2.73x10-14 3.52x10-14

100Mo 4.42x10-14 5.73x10-14

116Cd 4.68x10-14 6.22x10-14

130Te 4.14x10-14 5.54x10-14

136Xe 4.37x10-14 5.91x10-14

150Nd 1.94x10-13 2.70x10-13

There is a difference of about 25%

Unit:y Suhonen + SM Rodin

Isotope suhonen shell modeltubingen (QRPA gA=1)

erratum_tubingen (RQRPA gA=1.25)

130Te 3,49 2,41 1,36 2,95

116Cd 3,75 2,94 1,31 2,42

76Ge 3,33 2,58 2,48 3,92

136Xe 4,64 2 0,94 1,97

82Se 3,44 2,49 2,1 3,49

100Mo 2,97 1,24 2,78

150Nd 1,96 4,16