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Final Results of the Sudbury Neutrino Observatory
The CAP'09 CongressMoncton, 7-10 June, 2009
Alain BelleriveOn behalf of the SNO CollaborationCarleton University, Ottawa, Canada
Final Results of the Sudbury Neutrino Observatory
The CAP'09 CongressMoncton, 7-10 June, 2009
Alain BelleriveOn behalf of the SNO CollaborationCarleton University, Ottawa, Canada
From Solving the Solar Neutrino Problem to Precision Physics
Outline Introduction
Solar Neutrino Flux (update)
The Sudbury Neutrino Observatory
The new stuff for 2011 (3-phase) !!!
New hep neutrino results
Expected 8B neutrinos survival probability
Constraints on Oscillation Parameters
Future Prospects
Rencontre de Blois May 29 – June 3, 2011 A.Bellerive
Evidence for Neutrino Mixing
Earth
Underground νe detector
Solarcore
Primary neutrino sourcep + p D + e+ + νe
Sun
~10 8 kilometers
Cosmic-rayshower
π0π+
µ+
νe
e+
νµ
νµ
Underground νe, νe, νµ, νµ
detector
Atmospheric neutrino sourceπ+ µ+ + νµ
e+ + νe + νµπ– µ– + νµ
e– + νe + νµ
~30 kilometers
30 meters
νe detectorNeutrinos νe, νµ, and νµ
Proton
beam
Pions
Copper beam stop
Muons and electrons
Watertarget
Solar Neutrinoslow energies
Atmospheric Neutrinoshigh energies
Beamstop Neutrinostunable energies
2 ≠eν
ν µ
First evidence of neutrino oscillation
Today’s talk !!!
Parallel Session Talk by Dr. Yoshihisa Obayashi
h
The First Piece
Solar Neutrino Flux and Physical Observables
The Sun produces υe in fusion nuclear reactions
Survival probability depends on the neutrino energy
Solar neutrino oscillation occurs inside the Sun
±1%
±6%
BPS08
±6% ±1.1%
±11%
±16%
Borexino
Neutrino Production in the Sun
Earth
Underground νe detector
Solarcore
Primary neutrino sourcep + p D + e+ + νe
Sun
~10 8 kilometers
Light Element Fusion Reactions
p + p →2H + e+ + νe
p + e- + p → 2H + νe
3He + p →4He + e+ + νe
7Be + e- →7Li + νe
99.75 %
0.25 %
15 %
~10-5 %
8B → 8Be* + e+ + νe 0.02 %
BPS08: (Bahcall) Pena‐Garay, C., & Serenelli, A. 2008. arXiv:0811.2424
http://www.sns.ias.edu/~jnb/
±1%
±6%
BPS08
±6% ±1.1%
±11%
±16%
Borexino
Neutrino Production in the Sun
Earth
Underground νe detector
Solarcore
Primary neutrino sourcep + p D + e+ + νe
Sun
~10 8 kilometers
Light Element Fusion Reactions
p + p →2H + e+ + νe
p + e- + p → 2H + νe
3He + p →4He + e+ + νe
7Be + e- →7Li + νe
99.75 %
0.25 %
15 %
~10-5 %
8B → 8Be* + e+ + νe 0.02 %
BPS08: (Bahcall) Pena‐Garay, C., & Serenelli, A. 2008. arXiv:0811.2424
http://www.sns.ias.edu/~jnb/
±1%
±6%
BPS08
±6% ±1.1%
±11%
±16%
Borexino
Neutrino Production in the Sun
Earth
Underground νe detector
Solarcore
Primary neutrino sourcep + p D + e+ + νe
Sun
~10 8 kilometers
Light Element Fusion Reactions
p + p →2H + e+ + νe
p + e- + p → 2H + νe
3He + p →4He + e+ + νe
7Be + e- →7Li + νe
99.75 %
0.25 %
15 %
~10-5 %
8B → 8Be* + e+ + νe 0.02 %
BPS08: (Bahcall) Pena‐Garay, C., & Serenelli, A. 2008. arXiv:0811.2424
http://www.sns.ias.edu/~jnb/
±1%
±6%
BPS08
±6% ±1.1%
±11%
±16%
Borexino
Neutrino Production in the Sun
Earth
Underground νe detector
Solarcore
Primary neutrino sourcep + p D + e+ + νe
Sun
~10 8 kilometers
Light Element Fusion Reactions
p + p →2H + e+ + νe
p + e- + p → 2H + νe
3He + p →4He + e+ + νe
7Be + e- →7Li + νe
99.75 %
0.25 %
15 %
~10-5 %
8B → 8Be* + e+ + νe 0.02 %
BPS08: (Bahcall) Pena‐Garay, C., & Serenelli, A. 2008. arXiv:0811.2424
http://www.sns.ias.edu/~jnb/
±1%
±6%
BPS08
±6% ±1.1%
±11%
±16%
Borexino
Neutrino Production in the Sun
Earth
Underground νe detector
Solarcore
Primary neutrino sourcep + p D + e+ + νe
Sun
~10 8 kilometers
Light Element Fusion Reactions
p + p →2H + e+ + νe
p + e- + p → 2H + νe
3He + p →4He + e+ + νe
7Be + e- →7Li + νe
99.75 %
0.25 %
15 %
~10-5 %
8B → 8Be* + e+ + νe 0.02 %
BPS08: (Bahcall) Pena‐Garay, C., & Serenelli, A. 2008. arXiv:0811.2424
http://www.sns.ias.edu/~jnb/
11
Sudbury Neutrino Observatory
FAAQ2006Alain Bellerive
υe
12
Solar Neutrino Mixing
quantity signed
21
22
212 mmm −=∆
mixingsolar 12 =θ
Survival Probability3 Parameters !
The state evolves with
time or distance
Pee ≡P(υe→υe)Pee = cos4(θ )[1-sin2(2θ )
sin2(ϕ)]Pee ≈ 1-sin2(2θ ) sin2(ϕ)where ϕ =1.27∆m2 L / E
Main Solar Physics:∆m2 & sin(2θ )
Experiment:Distance (L) & Energy (E)
1212
1213
12
12
small 13 =θ2-32
31 eV 10 2.3 ×±=∆m
The Second Piece:
Pre-SNO (~2001)
Solar Neutrino Problem (Pre SNO)
Experiment Medium Threshold (MeV)
Measured/SSM
Homestake Chlorine 0.814 0.34±0.03
SAGE+GALLEX/GNO Gallium 0.2332 0.52±0.03
SuperK H2O 7.0 0.406±0.013
Neutrino reactions
Source: arXiv:hep-ph/0406294
νe
~108 km
Measured PredictedPee
Phys.Rev. D64 (2001) 093007
LMA
Allowed Regions
SMA
LOW
VAC
JustSo2
∆m
2 (e
V2)
tan2θ
Combination of theChlorine, Gallium, SK, and CHOOZ
restricted the mixingparameters
Pre SNO (~2001) 212
2 mm ∆=∆
12 θθ = 013 =θ
TODAY
Mixing Parameters
Arranging the Pieces:
The Sudbury Neutrino Observatory
17
1700 tonnes InnerShield H2O
1000 tonnes D2O
5300 tonnes Outer Shield H2O
12 m Diameter Acrylic Vessel
Support Structure for 9500 PMTs, 60% coverage
Image courtesy National Geographic
Sudbury Neutrino
Observatory
6000 mwe overburden
17.8 m
Key signatures for ν mixing with SNO
18
τµ νννν
++=
ΦΦ
e
e
NC
CC
)(154.0 τµ νννν
++=
ΦΦ
e
e
ES
CC
Flavor change ? Pee(Eυ) ≠ 1 !CC
ES
NC
Timeline of SNO
Commissioning D2O + Salt D2O D2O + 3He counters
3He countersInstallCommission
1998 1999 2000 2001 2002 2003 2004 2005 2006 2007
D2O
Phase I Phase II Phase III
306days 391days 396days
PRL 87, 071301, 2001PRL 89, 011301, 2002PRL 89, 011302, 2002PRC 75, 045502, 2007
PRL 92, 181301, 2004PRC 72, 055502, 2005
Total of ~1100 live-days
PRL101, 111301, 2008
PRC, 055504, 2010
Upcoming… Phase I-II-III combined analysis
Combined Phase I-IILow Energy Threshold Analysis
DataAnalysis
Soon!
SNO Phases I+II Major Improvements Tune up the Monte Carlo on calibration data based on 5 years of
operational experience - Reduction of systematic uncertainties Improve optics (especially at large radii) with late light and new
energy estimator (improve energy resolution by 6%)
Energy ThresholdD2O phaseTeff = 5 → 3.5 MeVSalt phaseTeff = 5.5 → 3.5 MeV
Improve statistics CC by ~40% NC by ~70%
Allow to fit the background wall
Night
Day
Pee typical LMA
Eν
No distortion, no D/N:∆χ2 = 1.94 / 4 d.o.f.LMA-prediction:
∆χ2 = 3.90 / 4 d.o.f.
Previous global best-fit LMA point tan2θ12=0.468 ∆m2=7.59x10-5 eV2
DAY
NIGHTADN
Φ(8B) = 5.046in units of 106 cm−2 s−1
SNO Phases I+IIDirect joint-phase fit of Pee
PRC, 055504, 2010
Previous global best-fit LMA point tan2θ12=0.468 ∆m2=7.59x10-5 eV2
Previous global best-fit LMA point tan2θ12=0.468 ∆m2=7.59x10-5 eV2
+0.159 +0.107 -0.152 -0.123
SNO NCD’s Phase III
n
Ni wall
3He:CF4 gas
Cu wire19
1 ke
V
573
keV
764
keV
PRL101, 111301, 2008
Global View
Data Sets Solar Oscillation Analysis Radiochemical : Cl, Ga
– Ga rate: 66.1 ±3.1 SNU SAGE+GNO/GALLEX [PRC80, 015807(2009)]– Cl rate: 2.56 ±0.23 [Astrophys. J. 496 (1998) 505]
SK– SK-I 1496 days, zenith spectrum E ≥ 5.0 MeV– SK-II 791 days, spectrum + D/N E ≥ 7.5 MeV
Borexino– 7Be rate: 49 ± 5 cpd/100tons [PRL101, 091302(2008)]
SNO– Phase I + II (PMT Low Energy threshold E ≥ 4.0 MeV)– Phase III (NCD and PMT E ≥ 6.5MeV)
KamLAND reactor experiment: 2008 [PRL100, 221803 (2008)]
8B spectrum: W. T. Winter et al., PRC 73, 025503 (2006).
Oscillation Analyses: Global Solar
Best-fit LMA point:
tan2θ12 = 0.457 (+0.038 -0.041)
∆m2 = 5.89x10-5 eV2
(+2.13 -2.16)
Φ(8B) = 5.104in units of 106 cm−2 s−1
-2.95ΔΦ8B = +3.90 %
12
2ν model
Best-fit LMA point:
tan2θ12 = 0.457
θ12=34.06 deg
∆m2 = 7.59 x10-5 eV2
Solar + KamLAND 2-flavor
2ν model
-0.029+0.040
+0.20 -0.21
+1.16-0.84
-2.95ΔΦ8B = +2.37 %
Φ(8B) = 5.013in units of 106 cm−2 s−1
12
3ν model
Solar + KamLAND 3-flavor
Best-fit: sin2θ13=2.00 +2.09
-1.63 x10-2
sin2θ13 < 0.057 (95% C.L.)
Best-fit LMA point:
tan2θ12 = 0.468
∆m2 = 7.59 x10-5 eV2
-0.023+0.042
+0.21 -0.2112
Remark: SNO and SK global oscillation analyses consistent
28
Sudbury Neutrino Observatory
FAAQ2006Alain Bellerive
Newest stuff for summer 2011 !!!
SNO hep neutrino sensitivity (3-phase)
SSM
Preliminary fit to all SNO data
Φ(hep) < 21×103 ν/cm2/s (90% CL)
All phases combined D2O+Salt+NCD8B Pee(Eν) fit
SNO Full 3-Phase Expected improvement
Δχ2
Δχ2
Peeday
ADN
Conclusion & Future Great physics out of solar neutrino experiments
From solving SNP to precision physics Direct evidence of solar neutrino oscillation by SNO Global solar solution favors LMA (Cl+Ga+SK+BX+SNO)
SNO: 3-flavour analysis Upcoming new and final SNO I+II+III publication
Almost ready… to be expected for TAUP 2011 Expect further improvement with SNO 3-phase analysis
The only model-independent fit of solar survival probability
Rencontre de Blois May 29 – June 3, 2011 A.Bellerive
Merci !
Thank you!
Rencontre de Blois May 29 – June 3, 2011 A.Bellerive