DARK 2007 Sydney Sept 28 th ,2007 Page 1 Knowing the Universe from a Hole in the Ground Particle-Astrophysics Research at SNO & SNOLab T. Noble, Queen’s University The Past The Sudbury Neutrino Observatory ( SNO ) • Current Status The Future SNOLab • Physics potential • Status
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DARK 2007 SydneySept 28 th,2007Page 1 Knowing the Universe from a Hole in the Ground Particle-Astrophysics Research at SNO & SNOLab T. Noble, Queen’s University.
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DARK 2007 Sydney Sept 28th,2007 Page 1
Knowing the Universe from a Hole in the Ground
Particle-Astrophysics Researchat
SNO & SNOLab
T. Noble, Queen’s UniversityThe Past
The Sudbury Neutrino Observatory ( SNO )
• Current Status
The Future
SNOLab
• Physics potential
• Status
DARK 2007 Sydney Sept 28th,2007 Page 2
SNO
Status• Data acquisition, NCD phase, complete November 28,
2006• Heavy water returned by May, 2007• Analysis proceeding well. • Primary focus:
– NC and CC data from NCD Phase.– Low Energy Threshold Analysis (LETA) from previous phases.
• Analysis will continue until April 2009
Main Results:
•30 year old Solar Neutrino Puzzle solved… •Strong evidence for weak flavor change (> 7 sigma). Solar Neutrino Oscillations! Neutrinos have finite mass, mix…•Total Flux in excellent agreement with expectations from solar
models We have a good understanding of the fusion processes in the
Sun…
DARK 2007 Sydney Sept 28th,2007 Page 3
Getting The Last Drop Out!
DARK 2007 Sydney Sept 28th,2007 Page 4
SNO data taking is Complete.
The Experiment is Decommissioned.
What is the future programme for Particle Astrophysics at this Facility?
DARK 2007 Sydney Sept 28th,2007 Page 5
SNOLAB
A new International Facility for Underground Science.
DARK 2007 Sydney Sept 28th,2007 Page 6
Physics Program• Direct Search for Dark Matter 85% of mass in universe + MSSM DEAP/CLEAN, PICASSO,
SNO+ (SNO with Liquid Scintillator)• heavy water is returned• replace with liquid scintillator and use existing SNO apparatus• Inexpensive, could be collecting data soon!
What can be measured?• low energy solar neutrinos - pep, CNO, 7Be• geo-neutrinos - anti-neutrinos from U/Th• reactor neutrinos - Bruce and Darlington• live for supernova • potential for large mass 0υbb decay experiment with 150Nd
What are the challenges?- some re-engineering of experiment- purification of scintillator
DARK 2007 Sydney Sept 28th,2007 Page 17
150Nd Option
• 3.37 MeV endpoint
• (9.7 ± 0.7 ± 1.0) × 1018 yr 2half-life (measured by NEMO-III)
• isotopic abundance 5.6%
1% natural Nd-loaded liquid scintillator in SNO+ has 560 kg of 150Nd compared to 37 g in NEMO-III !!
• Isotopic Enrichment:– SuperNEMO and SNO+, MOON and DCBA are supporting
efforts to maintain an existing French AVLIS facility that is capable of making 100’s of kg of enriched Nd
DARK 2007 Sydney Sept 28th,2007 Page 18
0: 1000 events per year with 1% natural Nd-loaded liquid scintillator in SNO+
Poor energy resolution compensated by high statistics
Test <m> = 0.150 eV
maximum likelihood statistical test of the shape to extract 0 and 2 components…~240 units of 2 significance after only 1 year!
Klapdor-Kleingrothaus et al., Phys. Lett. B 586, 198, (2004)
simulation:one year of data
DARK 2007 Sydney Sept 28th,2007 Page 19
SNO+ Double Beta Spectrum
1 yr, 500 kg isotope, m = 150 meV
DARK 2007 Sydney Sept 28th,2007 Page 20
Statistical Sensitivity in SNO+
500 kg isotope 56 kg isotope
• 3 sigma detection on at least 5 out of 10 fake data sets• 2/0 decay rates are from Elliott & Vogel, Ann. Rev. Nucl. Part. Sci. 52, 115 (2002)
DARK 2007 Sydney Sept 28th,2007 Page 21
SNO+ vs. Super-Kamiokande
CC: (260) 41% (7000) 91%
(30) 4.7%
(10) 1.5%
NC: (60) 9.3% (410) 5%
(270) 42%
ES: (12) 1.9% (300) 4%
SN Neutrino Detection in SNO+
DARK 2007 Sydney Sept 28th,2007 Page 22
XeXe off ers a qualitatively new tool against background:off ers a qualitatively new tool against background:136136Xe Xe 136136BaBa++++ee-- ee-- final state can be identified final state can be identified
using optical spectroscopy using optical spectroscopy ((M.MoeM.Moe PRC44 (1991) 931)PRC44 (1991) 931)
BaBa++ system best studiedsystem best studied((NeuhauserNeuhauser, , HohenstattHohenstatt,,ToshekToshek, , DehmeltDehmelt 1980)1980)Very specific signatureVery specific signature
““shelvingshelving””Single ions can be detectedSingle ions can be detectedfrom a photon rate of 10from a photon rate of 1077/s/s