the birth of the neutrino fiorini , varenna june 17, 2008 1. named neutrino by enrico fermi =>...

The importance of being “Neutrino”

The birth of the neutrino

Ettore Fiorini , Varenna June 17, 20081

Named Neutrino by Enrico Fermi => first properties of weak interactrions

ν e

n p

GF (Fermi constant)

Ettore Fiorini , Varenna June 17,2008

2


3

More than 70 years of searches => parity violation, three flavours,lepton and flavor conservation (???)

Charged currents

Neutral currents

Ettore Fiorini , Varenna June 17, 2008 4

Neutrino oscillations


Solar neutrinos ( νe)

Spectrum of solar neutrinos



SNO and the New SNOLAB


Geo-Neutrinos

• can we detect the antineutrinos produced bynatural radioactivity in the Earth?

radioactive decay of heavy elements(Uranium, Thorium) produces

antineutrinos

e ⇒

10

Super-Kamiokande

νe ~ as predicted νµ deficit from below


Atmospheric neutrinos

Reactor Neutrinos


2002:


1051 m280 m

Double-CHOOZ (France) σινσιν22θ13 < 0.022θ13 < 0.022

σιν

σιν

22 2θ13

2θ13

0.030.03

Daya Bay (China)

DOUBLE CHOOZDOUBLE CHOOZ

Reactors (the future)


Minos K2K

Simulated tau event:

Accelerators

Two different hierarchy models



15

CMB AnisotropyµK nK

WMAP

BOOMERanG DASI


<mν> from Cosmology

mν = 0 eV mν = 1 eV

mν = 7 eV mν = 4 eV

Tiny effect ->

Measurement (or limit ) on neutrino mass by single beta decay


Katrin

3H => 3He + e- + νemν

< 2.2 eV => KATRIN < 0.2 eV



19

The cryogenic or thermal detectors


First ideas

1880 => Langley => resistive bolometers for infrrared from SUN

1905 => Curie et Laborde => calorimetric measurement of radioactivity

1927 => Ellis and Wuster => heat less then expected => the neutrino

1935 => Simon => sensitivity enhanced by lowering the temperature

1983 => T.Niinikoski =>observe pulses in resistors due to cosmic rays

=> McCammon et al (NASA-Wisconsin) Low temp. detectors for astrophysics and neutrino mass measurement1984 => Fiorini and Niinikoski Low temperature detectors for rare events



23

Incidentparticle

absorber crystal

Thermal sensor

Excellent resolution <1 eV ~ 2eV @ 6 keV ~10 eV ~keV @ 2 MeV

VC

Q T =!

J/K )( v

v 1944 C 3

m

V

T

!=


Non equilibrium and equilibrium detectors

-

- Various types of thermometers

=> a thermistor => a transition edge sensor (TES) => an Equilibrium Absorber weakly coupled to a heat bath superconducting tunnel junction (STJ) Cooper pair breaking => a magnetic thermometer . The temperature information is obtained from the change of a paramagnetic sensor placed in a small magnetic field

Caveat => possibility that the heat capacity of the thermometer be comparable or larger than the absorber one:


Non equilibrium detectors

⇒ STJ Superconducting tunnel junctions⇒ SSG Superheated superconducting granules . The field does not enter

more in the granule. Often SQUID pickup Suggested for In solarneutrino detection. Considered for Dark Matter Experiments

=> Superfluid 3He and 4He detectors (rotons) . Also considered forSolar neutrinos

Comparison with conventional detectors:

=> Slow propagation of the vibration inside the absorber Kapitza resistence detector => heat sink (slow rise and decay times)

=> Possible localizazion of the event (TES)


Macro and micro bolometers


Energy resolution of a TeO2 crystal of 5x5x5 cm3 (~ 760 g )

:0.8 keV FWHM @ 46 keV1.4 keV FWHM @ 0.351 MeV2.1 keV FWHM @ 0.911 MeV2.6 keV FWHM @ 2.615 MeV3.2 keV FWHM @ 5.407 MeV

(the best α spectrometer so far

Energy [keV]

210Po α line


Orpheus 0.45 kg of granules 70 m.w.e for Dark Matter detection BernConsidered also for double beta decay (A.Morales)


Q inner

Q outer

A

B

D

C

Rbias

I bias

SQUID array Phonon D

Rfeedback

Vqbias

Hybrid techniquesheat + ionization or heat + scintillation


The scintillating bolometerProved for CaF2 being studied for TeO2



8751 hours x mg (AgReO4)

MIBETA: Kurie plot of 6.2 ×106 Re ß-decay events (E > 700 eV)

10 crystals:

E0 = (2465.3 ± 0.5stat ± 1.6syst) eV

MANU2 (Genoa)metallic Rhenium

m ν< 26 eVNucl. Phys. B (Proc.Suppl.) 91 (2001) 293

MIBETA (Milano)AgReO4

mν < 15 eV

MARE (Milano, Como,Genoa, Trento, US, D)Phase I : mν < 2.5 eVm2

ν = (-112 ± 207 ± 90) eV2

Nucl. Instr. Meth. 125 (2004) 125

hep-ex/0509038

Microcalorimeters for Microcalorimeters for 187187Re ß-decayRe ß-decay

A new fact in Material Science and Nuclear Physics=> Beta Environmenthal Fine Structure 187 Re => 187 Os + e- + ¯νe ΔE = 2.5 keV

The Genoa spectrum with metallic Rhenium


The structure of BEFS has allowed to determine the P to S ratio of thebeta decay


e- + 163 Ho => 163 Os + νe also for searches on neutrino mass

113 Cd => 113 I + e- + ¯ νe τ1/2 = (9+1) x 1015 y

e- + 123 Te => 123 Sb + νe τ1/2 > 1015 y

e- + 7 Be => 7 Li + νe => for solar neutrinos

e- + Ga => 71 Ge + νe => for solar neutrinos

First discovery of the decay 209 Bi => 204 Tl + α

Experiments with heavy ions

Other interesting results in nuclear physics obtatined withcryogenic detctors


ProblemsProblems of of cryogeniccryogenic detectorsdetectors::The are slowThe are slow

and and totallytotally sensitive sensitivesurfacesurface contaminationcontamination


What about the nature of the neutrino and its mass?


→ →<= =>

Majorana=>1937

Neutrinoless double beta decay and Majorana neutrinos

RIGHT

LEFTν:

ν:

39Ettore Fiorini , Varenna June 17, 2008

1. (A,Z) => (A,Z+2) + 2 e- + 2 νe¯2. (A,Z) => (A,Z+2) + 2 e- + χ ( …2,3 χ)3. (A,Z) => (A,Z+2) + 2 e-



41


Double Beta –Disintegration

M.Goeppert-Mayer, The John Hopkins University(Received May, 20 , 1935)

From the Fermi theory of β- disintegration the probability ofsimultameous emission of two electrons (and two neutrinos) has been

calculated. The result is that this process occurs sufficiently rarely to allowan half-life of over 1017 years for a nucleus, even if its isobar of atomicnumber different by 2 were more stable by 20 times the electron mass

At the beginning At the beginning neutrinolessneutrinoless ββββ decay decay searched as the most powerful methodsearched as the most powerful methodto testto test conservation of lepton number. conservation of lepton number. Today, after discovery of Today, after discovery of neutrinoneutrino

oscillationsoscillations represents the best way to measure represents the best way to measure < <mmνν>>

u e -d

de -

W

u

νe

νe

2ν - ββ decay

W

0ν - ββ decay

e -

e -

d

du

u

WW

eνe

ν

Neutrinoless ββ decay



Predictions from neutrino oscillations

Experimental approach

Direct ex-perimentsSource ≠ detectorSource = detector

(calorimetric)

Geochemical experiments82Se = > 82Kr, 96Zr = > 96Mo, 128Te = > 128Xe (non confirmed), 130Te = > 130Xe

Radiochemical experiments238U = > 238Pu (non confirmed)

e-

e-



46

49

Nucleus T0n (y) 1 2 3 5 6 Faessler (Erratum)

48Ca >1.4x1022 2276Ge >1.9x1025 .47 .55 .41 .97 .84 .36 ±.0776Ge >1.6x1025 .51 .60 .44 1.1 .91 .40±.0876Ge 1.2x1025 .59 .69 .52 1.2 1.1 .46±.0982Se >2.1.x1023 2.2 2.9 1.8 2.8 3.7 1.9±2.0100Mo >5.8x1023 .97 2.7 1.1 11 1.1 ±.3116Cd >1.7x1023 2.4 3.5 1.4 2.7 2.3±.8128Te >7.7×1024 1.8 2.5 4.6 2.0 1.5±.6130Te >3x1024 .7 .85 .37 1.1 1.8 .48±.15136Xe >1.2x1024 2.9 2.0 .42 2.6 1.2±.5150Nd >1.2x1021 2.7 4.4 1.0 .84 8±4

1/τ = G(Q,Z) |Mnucl|2

<mν>2

rate of DDB-0ν Phase space Nuclear matrix elements EffectiveMajorana

neutrino mass

The rate of neutrinoless DBD


Claim of Evidence for 0νββ in 76Ge

Single-site events in detectors 2, 3, 4, 5 (56.6 kg-y).H.V. Klapdor-Kleingrothaus, Int. J. Mod. Phys. E17, 505 (2008)

<m> ~ 0.2 to 0.3 eV

Looks good to me…not to me (E.F.)

Two new experiments NEMO III e CUORICINO


Searches withthermal detectors

Cuoricino (Hall A)

CUORE (Hall A)

CUORE R&D (Hall C)


Mass increase of bolometers

year

tota

l mas

s [k

g]


DetectorsDetectors assemblingassembling

Operations carried outIn a clean room



55

11 modules, 4 detector each,crystal dimension 5x5x5 cm3

crystal mass 790 g4 x 11 x 0.79 = 34.76 kg of TeO2

2 modules, 9 detector each,crystal dimension 3x3x6 cm3

crystal mass 330 g9 x 2 x 0.33 = 5.94 kg of TeO2

Search for the 2β|oν in 130Te (Q=2529 keV) and other rare events

At Hall A in the Laboratori Nazionali del Gran Sasso (LNGS)

18 crystals 3x3x6 cm3 + 44 crystals 5x5x5 cm3 = 40.7 kg of TeO2Operation started in the beginning of 2003 => ~ 4 months

Background .18±.01 c /kev/ kg/ a T 1/2 0ν (130Te) > 3.1 x 1024 y <mν> .16 -.84 eV

Klapdor 0.1 – 0.9


Cosmological disfavoured region (WMAP)

Direct hierarchyΔm2

12= Δm2

sol

Inverse hierarchyΔm2

12= Δm2atm

“quasi” degeneracym1≈ m2 ≈ m3

With the same matrix elements the Cuoricino limit is 0.53 eV

Present Cuoricino region

Possible evidence(best value 0.39 eV)

Feruglio F. , Strumia A. , Vissani F. hep-ph/0201291

Arnaboldi et al., submitted to PRL, hep-ex/0501034(2005).


57

Experiment Nucleus Detector

NEMO III 100

Mo et al 10 kg of enrich. Isotopes -tracking

Cuoricino 130Te + etc. 40 kg of TeO 2 bolometers (nat)

CUORE 130

Te + etc. 750 kg of TeO 2 bolometers (nat)

EXO 136

Xe 200kg - 1 t Xe TPC

GERDA 76

Ge 30-40 kg - 1t Ge diodes in LN

Majorana 76

Ge

180 kg - 1t Ge diodes

MOON 100Mo nat.Mo sheets in plastic sc.

DCBA 150

Nd

20 kg Nd -tracking

CAMEO 116

Cd

1 t CdWO 4 in liquid scintillator

COBRA 116

Cd , 130

Te

10 kg of CdTe semiconductors

Candles 48Ca Tons of CaF 2 in liquid scintillators

GSO 116

Cd

2 t Gd 2SiO5:Ce scintill.in liquid sc.

Xe 136

Xe

1.56 Xenon in liquid scintillator.

Xmass 136

Xe

1 t of liquid Xe

MOON

CUORE

GERDA

EXO

CUORICINO

22PP1/21/2

44DD3/23/222SS1/21/2

493 nm493 nm650 nm650 nm

metastablemetastable 47s47s

Experimental situation

58

CUORE

SNO++

MOON

NEMO - SuperNEMO

CUORE CUORE expectedexpected sensitivitysensitivity

disfavoured by cosmology

11-576.5 _ 10 26510-3

19-1002.1 _ 10 26510-2

<m!> [meV]T1/2 [y]"

[keV]b (counts/keV/kg/y)

11-576.5 _ 10 26510-3

19-1002.1 _ 10 26510-2

<m!> [meV]T1/2 [y]"

[keV]b (counts/keV/kg/y)

Strumia A. and Vissani F. hep-ph/0503246

In 5 years:


59

Compound Isotopic abundance Transition energy

48CaF2 .0187 % 4272keV76Ge 7.44 " 2038.7 "

100MoPbO4 9.63 " 3034 "

116CdWO4 7.49 " 2804 "130TeO2 34 " 2528 "

150NdF3150NdGaO3

5.64 " 3368“

Other possible candidates for Other possible candidates for neutrinolessneutrinoless DBD DBD


Neutrino oscillations exist => Δm ν 2 ≠ 0

Future experiments will enable to investigate in details the parameters of this processDetermination of the absolute value of <mν > becomes imperativeTheory indicates <mν > from a from few to a few tens of meV.The study of Cosmic Microwave Background determines the sum of neutrino masseswith high precision. How much model dependent?Single beta decay constraints directly <m ν> but still far from predictionsFuture experiment on neutrinoless double beta decay could determine <mn > at thelevel predicted by neutrino oscillations under the inverse hierarchy hypothesis, andascertain if neutrino is a Majorana particleThe present claim for this phenomenon indicating <mν > ~0.44 eV is not confirmed byCUORICINOThe most advanced and sometime not yet tested nuclear physics techniques are beingstudied for future DBD experimentDeterminaion of neutrino mass involves already nuclear and sub nuclear physics. Itspeculiar multidisciplinarity involves fundamental problems in astroparticle physics,radioactivity’, materials, geochronology ecc.Very stimulating for young people

CONCLUSIONS


From now on one should discuss seriously all side ofthe problem. Therefore , dear radioactive people , doinvestigate and judge.

Unfortunately I cannot be personally inTubingen since my presence is absolutelyindispensable here for a ball that will take place herein the night between December 6 and 7.

Your devoted servantWolfang Pauli


From the letter of From the letter of WolfangWolfang PauliPauli of December 1, 1930 of December 1, 1930

the birth of the neutrino fiorini , varenna june 17, 2008 1. named neutrino by enrico fermi =>...

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