zoneconvective

2e-+4p 4He+2e MeVcoeur

zoneradiative

500'000 km

(70% 1H, 28% 4He,...)

e

L=1.44 1011 m.

Le soleil

100

10-2

101

10-1

10-3

107

106

105

104

r[R ]

g cm-3]T[K]102108

T=107K: plasma with Tcin0.8 keV,

enough for penetration through Coulomb barrier via tunnel effect,

nuclear reactions

8B 8Be+e++e+14.6 MeV

3He+3He 4He+2p+12.86 MeV

p+p 2H+e++e+0.42 MeV

0.25 %99.75 %

2H+p 3He++5.49 MeV

3He+4He 7Be++1.59 MeV

86 %

14 %

Q=26.2 MeV

p+e-+p 2H+e+1.44 MeV

7Be+e- 7Li+e+0.87 MeV 7Be+p 8B++0.14 MeV

99.89 % 0.11 %

7Li+p 4He+4He+17.35 MeV

Q=25.7 MeV

8Be 4He+4He+3 MeV

Cycle pp(98.5 % de la luminosité)

12C+p 13N+

13N 13C+e++e (1.2 MeV)

13C+p 14N+

14N+p 15O+

15O 15N+ e++e (1.73 MeV)

15N+p 12C+4He

Cycle CNO (1.5 % soleil)

112 MeVscm

SNO

• CC interaction sensitive only to e. Proposed by Pontecorvo in 1946.

N* is extracted from the target with physical-chemical techniques and identified by its decay back in N.

1 Solar Neutrino Unit [SNU] = 1 interaction/sec each 1036 target atoms.

Radiochemical experiments e*NNe

2-46i cm 10 ~

)()(

)(i)( target dEPdE

EdENRRatenInteractio ee

ii

eAuger,raysXN*Ne eL,K

37Cl(e,e)37Ar (Ethr = 813 keV) Kshell EC t = 50.5 d

37Cl + 2.82 keV (Auger e-, X)

615 t C2Cl4 tank, in Homestake mine (4400 mwe) 30102.2 37Cl atoms (nat abundance 24 %)

Every 30 days inject 0.2 cc Ar, purge with He to remove 37Ar, fill prop. counter

pep 0.2 SNU 7Be 1.2 SNU 8B 6.2 SNU CNO 0.4 SNUTot calc. 8.1 ± 1.8

Measured 3.23 SNU ± 0.68 (0.46-0.08=0.38 atom/day)

cosmic background

Bahcall and

Pinsonnault

+SSM

Gallex-GNO Gran Sasso lab (3500 mwe)

)d4.11T(

GaEC

eGeGa

2/1

e71

7171e

30 t of Ga (40 % 71Ga) GeH4

Eth=0.233 MeV

Calibration with 51Cr source

day-1 SNU

pp 0.61 70.8 pep 0.02 3.0 7Be 0.30 34.3 8B 0.10 14.0 CNO 0.08 9.9 tot 1.14 132

tot 0.61 70.8 4

tot 66.9 5

BP+SSM

Gallex-GNO measured

SAGE (metallic Ga)

Deficit of solar neutrinos

Superkamiokande (Japon) :

50 kt H2Ophotomultiplicateurs

queatmosphéri,

)km104.1L(solaires

e

8e

)km300L(KEK

)km1200030L(

ee ee XeNXN e

)()()()(

XeNXN e

1000 tonnes D2O

12 m diameter Acrylic Vessel

18 m diameter support structure; 9500 PMTs (~60% photocathode coverage)

1700 tonnes inner shielding H2O

5300 tonnes outer shielding H2O

Urylon liner radon seal

depth: 2092 m (~6010 m.w.e.) ~70 muons/day

Sudbury Neutrino

Observatory

SNO, construction of acrylic vessel

Acrylic vessel+PMT

Water purification system Photos courtesy of SNO

Neutrino Reactions in SNO

- Q = 1.445 MeV- good measurement of e energy spectrum- some directional info (1 – 1/3 cos)- e only

- Q = 2.22 MeV - measures total 8B flux from the Sun- equal cross section for all active flavors

NCxx

npd

ES e−e− x

- low statistics - mainly sensitive to e, some and - strong directional sensitivity

CC e−ppd e

x

Čerenkov Detection

PMT MeasurementsPMT Measurements

-positionposition-chargecharge-timetime

Reconstructed EventReconstructed Event

--event vertexevent vertex-event direction-event direction-energy-energy-isotropy-isotropy

SNO Neutral Current Trilogy

Pure D2O

Nov 99 – May 01

n d t

(E = 6.25 MeV)

good CC

PRL 87, 071301 (2001)

PRL 89, 011301 (2002)

PRL 89, 011302 (2002)

“D2O Archival Long Paper” in progress

Salt

Jul 01 – Sep 03

n 35Cl 36Cl

(E = 8.6 MeV)

enhanced NC and event isotropy

PRL 92, 181301 (2004)

“Long Salt Paper” soon to be submitted

3He Counters

Fall 04 – Dec 06

n 3He t p

proportional counters = 5330 b

event-by-event separation

“First NCD Paper” in the future

Physics Motivation

Event-by-event separation. Measure NC and CC in separate data streams.

Different systematic uncertainties than neutron capture on NaCl.

3He array removes neutrons from CC, calibrates remainder. CC spectral shape.

Detection Principle

2H + x p + n + x - 2.22 MeV (NC)

3He + n p + 3H + 0.76 MeV

40 Strings on 1-m grid

398 m total active length

x

nNCD

PMT

SNO Phase III: 3He Detectors 3He Proportional Counters (“NC Detectors”)

391 days salt phase

Favored channel: ,e

N=235U, 238U, 239Pu, 241Pu

fission/MeV58.200Q

5.2kQnk)Z,A()Z,A(UUn 2211

236

92

235

92th

600 K (PWR)

A

Fragment distribution

ee)1Z,A()Z,A(

MeV70E

fission/65 e

PWR: 238U+3.5 % 235U (start)

nth+239Pu, 241Pu

nfast+238U

MeV8.1TE

MeVcm1014.9ApEA

e

2244

ee

nepe

e e (disappearance experiment)

Pth= 8.4 GWth, L = 1.050 km, M = 5 t

overburden: 300 mwe

CHOOZ

nepe

• Prompt e+, EP=1-8 MeV, visible energy

• Delayed neutron capture on Gd, ED=8 MeV

• Prompt(/) - Delayed(/) some pulse shape discrimination information

• Directionality: weak & statistical (to be studied for the future)

Time correlation: 30sec

Space correlation: < 1m3

prompt event:

E prompt E En 0.8 MeVQ~1.8 MeV Threshold

0.7-9 MeV

delayed event:MeV)8(~'* sGdGdn

6-11 MeV

CHOOZ

Gd loaded scintillator (0.1 %)

CHOOZ

CHOOZ

2244ee MeVcm1014.9ApEA

KAMLAND

KAMLAND

Chooz: 13<130

solar

Kamland Kamland + solar

solar: Cl37+Gallex+SAGE+SK+SNO

reactor: Kamland

allowed area (95 % CL)

SK: day-night assymetry

measured: %6.18.1A 3.16.1N

,e

SK atmospheric neutrinos

ExpectedBest fit

Favored channel:

Favored channel:

Provide an unambiguous evidence for oscillations in the region of atmospheric neutrinos by looking for appearance in a pure beam

Search for the subleading e oscillations (measurement of 13 )

732 KmGiven the distance (732 Km): flux optimized for the maximal number of charged current interactions

<L/E> = 43 Km/GeV : « off peak »

<E> 17 GeV

(e+e)/ 0.87%

/ 2.1%

prompt negligible

CNGS PROGRAM:

OPERA: 6200 CC+NC /year 19 CC/year (@ 2 10-3 eV2)

8.3kg

10 X0

Pb

Emulsion layers

1 mm

The basic unit: the « Brick »

• Based on the concept of the Emulsion Cloud Chamber (ECC)• 56 Pb sheets 1mm + 56 emulsion layers• Solves the problem of compatibility of large mass for neutrino interactions + high space resolution in a completely modular scheme

ECC are completely stand-alone detectors: Neutrino interaction vertex and kink topology reconstruction Measurement of the momenta of hadrons by multiple scattering dE/dx pion/muon separation at low energy Electron identification and measurement of the energy of the electrons and photons

10.2 x 12.7 x 7.5 cm

ECC Tecnique validated by the direct observation of : DONUT 2000

supermodule

8 m

Target Trackers

Pb/Em. target

ECC emulsions analysis:

Vertex, decay kink e/ ID, multiple scattering, kinematics

Extract selected brick  

Pb/Em. brick

8 cm Pb 1 mm

Basic “cell”

Emulsion

trigger and localization of neutrino interactions muon identification and momentum/charge measurement need for a hybrid detector

Electronic detectors:

Brick finding, muon ID, charge and p

Link to mu ID,Candidate event

Use of the electronic detectors:

Spectrometer

Target Tracker

XY planes, 7000m2 in total32256 Scintillator strips 6.86m x 2.6cm x1cmAMCRYS-H (Kharkov) + Kuraray WLS

1000 MaPMT Hamamatsu 64channelsDedicated Front End electronics for gain correction Autotriggerable and threshold @ 1/5 p.eEthernet DAQ cardsWell above 5 p.e. /

readout end

(in the middle: worst case for two-end readout)

6.9m

Construction of the modules in progress (8/week)Installation at LNGS since September 2004

1.7 m

0 max

p.h.

Neutrino interaction trigger

Brick localization Muon tracking and ID

64 strips/module

OPERA structure with two Super-Modules

31 target planes / supermodule (in total: 206336 bricks, 1766 tons)

TargetsMagnetic Spectrometers

Proposal: July 2000, installation at LNGS started in May 2003

SM1 SM2

Data taking starts in 2006, prepare scanning!

sensitivity

full mixing, 5 years run @ 4.5 x1019 pot / year

signal

(m2 = 1.9 x 10-3 eV2)

signal

(m2 = 2.4 x 10-3 eV2)

signal

(m2 = 3.0x 10-3 eV2)

BKGD

OPERA1.8 kton fiducial

6.6(10) 10.5(15.8) 16.4(24.6) 0.7(1.06)

(…) with CNGS beam upgrade (X 1.5)

m2 (10-2 eV2)

Probability of observing in 5 years a number of candidates greater than a 4 background fluctuation

13, or Ue3= Y. Giomataris and J.D. Vergados

Xenon(?) at 1 barR determined from lateral diffusion

3H 3He+e+e- (Q=18.6 keV)6x1018 /s

Tmax=1.27 keVEth=200 eV

Neutrino energy

(T>200 eV)

R(m)m2=2.5x10-3

eV2

=0.17