zone convective 2e - +4p 4 He+2 e  MeV coeur zone radiative 500'000 km (70% 1 H, 28% 4 He,...) e L= m. Le soleil

r[R ]  g cm -3 ] T[K] T=10 7 K: plasma with Tcin  0.8 keV, enough for penetration through Coulomb barrier via tunnel effect, nuclear reactions

8 B 8 Be+e + + e MeV 3 He+ 3 He 4 He+2p MeV p+p 2 H+e + + e MeV 0.25 % % 2 H+p 3 He+  MeV 3 He+ 4 He 7 Be+  MeV 86 % 14 % Q=26.2 MeV p+e - +p 2 H+ e MeV 7 Be+e - 7 Li+  e MeV 7 Be+p 8 B+  MeV % 0.11 % 7 Li+p 4 He+ 4 He MeV Q=25.7 MeV 8 Be 4 He+ 4 He+3 MeV Cycle pp (98.5 % de la luminosité)

12 C+p 13 N+   13 N 13 C+e + + e (1.2 MeV) 13 C+p 14 N+  14 N+p 15 O+  15 O 15 N+ e + + e (1.73 MeV) 15 N+p 12 C+ 4 He Cycle CNO (1.5 % soleil)

SNO

CC interaction sensitive only to e. Proposed by Pontecorvo in 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 target atoms. Radiochemical experiments

37 Cl( e,e) 37 Ar (Ethr = 813 keV) Kshell EC t = 50.5 d 37 Cl keV (Auger e -, X) 615 t C 2 Cl 4 tank, in Homestake mine (4400 mwe) 37 Cl atoms (nat abundance 24 %) Every 30 days inject 0.2 cc Ar, purge with He to remove 37 Ar, fill prop. counter pep0.2 SNU 7Be1.2 SNU 8B6.2 SNU CNO 0.4 SNU Tot calc.8.1 ± 1.8 Measured3.23 SNU ± 0.68 ( =0.38 atom/day) cosmic background Bahcall and Pinsonnault +SSM

Gallex-GNO Gran Sasso lab (3500 mwe) 30 t of Ga (40 % 71 Ga) GeH 4 E th =0.233 MeV

Calibration with 51 Cr source

day -1 SNU pp pep Be B CNO tot tot tot BP+SSM Gallex-GNO measured SAGE (metallic Ga) Deficit of solar neutrinos

Superkamiokande (Japon) : 50 kt H 2 O photomultiplicateurs

1000 tonnes D 2 O 12 m diameter Acrylic Vessel 18 m diameter support structure; 9500 PMTs (~60% photocathode coverage) 1700 tonnes inner shielding H 2 O 5300 tonnes outer shielding H 2 O 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 = MeV - good measurement of e energy spectrum - some directional info  (1 – 1/3 cos  ) - e only - Q = 2.22 MeV - measures total 8 B flux from the Sun - equal cross section for all active flavors NC xx    npd ES    e−e− e−e− x - low statistics - mainly sensitive to e, some  and  - strong directional sensitivity CC e−e− ppd  e x

Čerenkov Detection PMT Measurements -position -charge -time Reconstructed Event -event vertex -event direction -energy-isotropy

SNO Neutral Current Trilogy Pure D 2 O Nov 99 – May 01 n  d  t   (E  = 6.25 MeV) good CC PRL 87, (2001) PRL 89, (2002) PRL 89, (2002) “D 2 O Archival Long Paper” in progress Salt Jul 01 – Sep 03 n  35 Cl  36 Cl   (E  = 8.6 MeV) enhanced NC and event isotropy PRL 92, (2004) “Long Salt Paper” soon to be submitted 3 He Counters Fall 04 – Dec 06 n  3 He  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. 3 He array removes neutrons from CC, calibrates remainder. CC spectral shape. Detection Principle 2 H + x  p + n + x MeV (NC) 3 He + n  p + 3 H MeV 40 Strings on 1-m grid 398 m total active length x n NCD PMT SNO Phase III: 3 He Detectors 3 He Proportional Counters (“NC Detectors”)

391 days salt phase

Favored channel:

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

600 K (PWR) A Fragment distribution

PWR: 238 U+3.5 % 235 U (start) n th Pu, 241 Pu n fast U

e  e ( disappearance experiment) P th = 8.4 GW th, L = km, M = 5 t overburden: 300 mwe CHOOZ

Prompt e+, E P =1-8 MeV, visible energy Delayed neutron capture on Gd, E D =8 MeV Prompt(  /  ) - Delayed(  /  )  some pulse shape discrimination information Directionality: weak & statistical (to be studied for the future) Time correlation:   30  sec Space correlation: < 1m 3 prompt event: Q~1.8 MeV Threshold MeV delayed event: 6-11 MeV CHOOZ

Gd loaded scintillator (0.1 %)

CHOOZ

KAMLAND

Chooz:  13 <13 0

solar Kamland Kamland + solar

solar: Cl37+Gallex+SAGE+SK+SNO reactor: Kamland allowed area (95 % CL) SK: day-night assymetry measured:

SK atmospheric neutrinos Expected Best fit

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 Km Given the distance (732 Km):  flux optimized for the maximal number of  charged current interactions = 43 Km/GeV : « off peak » 17 GeV ( e + e )/  0.87%  /  2.1%  promptnegligible CNGS PROGRAM: OPERA: 6200  CC+NC /year 19   CC/year eV 2 )

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, 7000m 2 in total  Scintillator strips 6.86m x 2.6cm x1cm  AMCRYS-H (Kharkov) + Kuraray WLS  1000 MaPMT Hamamatsu 64channels  Dedicated Front End electronics for gain correction  Autotriggerable and 1/5 p.e  Ethernet DAQ cards Well 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 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: bricks, 1766 tons)  Targets Magnetic Spectrometers Proposal: July 2000, installation at LNGS started in May 2003 SM1SM2

Data taking starts in 2006, prepare scanning!

   sensitivity full mixing, 5 years 4.5 x10 19 pot / year signal (  m 2 = 1.9 x eV 2 ) signal (  m 2 = 2.4 x eV 2 ) signal (  m 2 = 3.0x eV 2 ) BKGD OPERA 1.8 kton fiducial 6.6(10)10.5(15.8)16.4(24.6)0.7(1.06 ) (…) with CNGS beam upgrade (X 1.5)  m 2 (10 -2 eV 2 ) Probability of observing in 5 years a number of candidates greater than a 4  background fluctuation

 13, or U e3 =  Y. Giomataris and J.D. Vergados Xenon(?) at 1 bar R determined from lateral diffusion 3 H 3 He+ e +e - (Q=18.6 keV) 6x10 18 /s T max =1.27 keV E th =200 eV

Neutrino energy (T>200 eV) R(m)  m 2 =2.5x10 -3 eV 2  =0.17