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Where do we find SNO in April?. Hamish Robertson Kubodera Festschrift April, 2004. Sudbury Neutrino Observatory. 1000 tonnes D 2 O. Support Structure for 9500 PMTs, 60% coverage. 12 m Diameter Acrylic Vessel. 1700 tonnes Inner Shielding H 2 O. 5300 tonnes Outer Shield H 2 O. - PowerPoint PPT Presentation
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Where do we find SNO in April?
Hamish RobertsonKubodera FestschriftApril, 2004
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Sudbury Neutrino Observatory
1700 tonnes InnerShielding H2O
1000 tonnes D2O
5300 tonnes Outer Shield H2O
12 m Diameter Acrylic Vessel
Support Structure for 9500 PMTs, 60% coverage
Urylon Liner andRadon Seal
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Heavy Water from Bruce Plant
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Reactions in SNO
NCxx
npd
ES -- ee x x
-Low Statistics -Mainly sensitive to e,, some
-sensitivity to and
-Strong direction sensitivity
-Gives e energy spectrum well-Weak direction sensitivity 1-1/3cos()- e only.
-Measure total 8B flux from the sun.- Equal cross section for all types
CC-epd e p
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Neutrino-deuteron interactions
Effective Field TheoryEFT (pionless)
Standard Nuclear Physics Approach (SNPA):
Potential modelHigher-order corrections
with mesons, ’sPrecision numerical calculation
Expansion of interactions in power series. Scattering length a, deuteron binding , momentum p are all small compared to pion mass (lowest non-nucleonic excitation)
K. Kubodera:NSGK, PRC63, 034617 (2001)NSA+, NP A707, 561 (2002)
Butler, Chen, Kong:BCK, PRC 63, 035501 (2001)
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EFT gives general results
• Leading order & NLO cross sections model-independent• Cross sections are analytic expressions• All observable parameters (doubly differential cross sections,
angular distributions, neutrino and antineutrino, CC & NC)• First undetermined term is in NNLO. Term is the weak axial
two-body current, called L1,A
Depend on L1A
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L1A can be fit to SNPA calculations
A SINGLE choice of L1A produces this agreement!
EFTSNPA
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EFT compared to Standard Nuclear Physics Approach
Ratio of Butler et al. (BCK) EFT with L1A = 4.0 fm3 to Nakamura et al. (NSA+)
CC
NC
MeV
EFT/SNPA
-
-
-
-
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Neutrino Flavor Composition of 8B Flux
Fluxes
(106 cm-2 s-1)
e: 1.76(11)
: 3.41(66)
total: 5.09(64)
SSM: 5.05
PRL 89, 011301, 2002
Shape-constrained fits. Pure D2O data.
BP04: 5.79 (1 0.23)
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L1A = 4.0
L1A = 20
ES
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Process L1A (fm3) Reference
CC, NC, ES 4.0 6.3 Chen et al., PRC 67, 025801 (2003), nucl-th/0210073
Reactor antineutrinos
3.6 4.6 Butler et al. nucl-th/0206026
Tritium decay
4.2 0.1 Schiavilla et al. PRC 58, 1263 (1998); Park et al. nucl-th/0106025 & nucl-th/0208055; Ando et al. nucl-th/02026001
Solar pp reaction
4.8 5.9 Brown et al. nucl-th/0207008
Potential model
4.0 Nakamura et al. NP A707, 561 (2002)
Determinations of L1A
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Total spectrum (NC + CC + ES)
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Less than Maximal Mixing at 3 Best Fit
m2 = 6.2 x 10-5 eV2
tan2 = 0.40
Flux/SSM = 1.06
3 Bounds
m2 < 3.3 x 10-4
tan2 < 0.80
tan2 < 1 implies m2 > m1
SOLAR LMASOLAR LMA
de Holanda and Smirnovhep-ph/0205241
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tan212-m122
Solar Only Solar+KL rate Solar+KL spect.€
φCC
φNC
⎛
⎝ ⎜
⎞
⎠ ⎟SNO
= 0.33−0.06+0.11 (99% CL)
€
φCC
φNC
⎛
⎝ ⎜
⎞
⎠ ⎟SNO
= 0.38−0.03+0.06 (99% CL)
de Holanda & Smirnov, hep-ph/0205241, hep-ph/0212270
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Advantages of NaCl for Neutron Detection
• Higher capture cross section• Higher energy release• Many gammas
n
36Cl*35Cl 36Cl
3H 36Cl
2H+n
35Cl+n
6.0 MeV
8.6 MeV = 0.0005 b
= 44 b
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Neutron Capture Efficiency in SNO
35Cl(n,)36Cl Average Eff. = 0.399Te ≥ 5.5 MeV and R ≤ 550 cm
2H(n,)3H Average Eff. = 0.144Te ≥ 5.0 MeV and R ≤ 550 cm
Radial Position of 252Cf Source, cm
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Cherenkov light and 14
) 43o
Charged particle, v > c/n
Hollow cone of emitted photons
Energy & Direction
ij
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Use of 14 to distinguish neutrons and e-
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Addition of Mott scattering to EGS4
Angular Distribution of 5 MeV electrons after passing through ~1 mm of water
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Blind Analysis
Three blindfolds for the analysts:
• Include unknown fraction of neutrons that follow muons
• Spoil the NC cross section in MC
• Veto an unknown fraction of candidate events
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14 Distributions for SNO Salt Data
Data from July 26, 2001 to Oct. 10, 2002
254.2 live days
3055 candidate events:
1339.6 +63.8 -61.5 CC
1344.2 +69.8 -69.0 NC
170.3 +23.9 -20.1 ES
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Sun-angle distributions
Toward sun Away from sun
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Energy spectra
Electron kinetic energy
Radioassay
• Bottom of vessel• 2/3 way up• Top of vessel
• MnOx• HTiO
• MnOx• HTiO
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Salt Phase: “Box” Opened Aug. 13, 2003
Shape of 8B spectrum in CC and ES not constrained:
Standard (Ortiz et al.) shape of 8B spectrum in CC and ES:
Pure D2O Phase
Salt Phase
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tan212-m122 before Salt Phase
Solar Only Solar+KL rate Solar+KL spect.€
φCC
φNC
⎛
⎝ ⎜
⎞
⎠ ⎟SNO
= 0.33−0.06+0.11 (99% CL)
€
φCC
φNC
⎛
⎝ ⎜
⎞
⎠ ⎟SNO
= 0.38−0.03+0.06 (99% CL)
de Holanda & Smirnov, hep-ph/0205241, hep-ph/0212270
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From the Salt Phase…
Ratio:
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Closing in on m2,
--90%--95%--99%--99.73%
LMA I only at > 99% CL
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Results from SNO -- Salt Phase
Oscillation Parameters, 2-D joint 1- boundary
Marginalized 1-D 1- errors
LMA II rejected at >99% CL
Maximal mixing rejected at 5.4
A paper plus a “companion” guide can be found at sno.phy.queensu.ca
Accepted (at last!) by PRL; nucl-ex/0309004.
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Mass (eV)
0.048
0.008
=0
Neutrino Masses and Flavor Content
3
e mu tau
Atmospheric
2
1
Solar
Atmospheric
2
1
Solar
=0 3
0.0400.039
0? ?
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neutrino masses: 0.048 < m1+m2+m3 < 6.6 eV Laboratory limit on fraction of universe closure density:
Large-scale structure limit :
Cosmological Implications
Atmospheric neutrinos: m232 2.0 10-3 eV2
One neutrino mass > 0.04 eV
SNO + KamLAND: m122 7.1 x 10-5 eV2
One neutrino mass > 0.008 eV
Limits on “e mass” give: m(1,2,3) < 2.2 eV
0.001 < < 0.13 < 0.02
32B. Cabrera, 2004
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Physics Motivation
Improved NC, NC/CC: 12
CC spectral shape: MSW, m2
Detection Principle
2H + x p + n + x - 2.22 MeV (NC)
3He + n p + 3H + 0.76 MeV Event-by-event separation..
Different systematic uncertainties than neutron capture on NaCl.
Measure neutrons separately: CC shape
x
n
40 Strings on 1-m grid
398 m total active length
NCD
PMT
SNO Phase III (NCD Phase)- Begins ‘04
3He Proportional Counters (“NC Detectors”)
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Why Event-by-Event?
Analyst: A. Hime
Breakingthe Correlation
J. Manor,M. Smith
QuickTime™ and aVideo decompressor
are needed to see this picture.
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Weld and Leak Check System
• Two NCD segments held by inflatable cuffs.
• Cuffs cast from approved silicone resin. • NCD holders insert into rotary stroke
bearings.• Rotation of both NCDs locked by
mechanical linkage with orbit motor.• Vertical position with 3 state cam and
fine screw.• Laser head can rotate and follow NCD
eccentricity.• Rotate NCD or rotate laser weld head.• Side port for making NCD wire
connection, He injection and sniffing.
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Lowering a welded string and its electrical cable
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Flying the ROV to the string’s anchor position.
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Installed 3He Counter Strings
N
3He
4He I4 I2
J3 K3 K2 J2
J4 L4 M3 M2 L1 J1
I3 K4 M4 N2 N1 M1 K1 I1
I5 K5 M5 N3 N4 M8 K8 I7
J5 L3 M6 M7 L2 J8
J6 K6 K7 J7
I6 I8
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Spectrum of 3He(n,p)3H in K6 string
Channel
Counts per channel 764 keVAmBe Source
Jan. 13, 2004
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Where do we find SNO in April?
Salt phase of SNO now complete. Another 150 days of data being analyzed. Spectral shape, day/night this summer.
Neutral-current detectors installed, checkout in progress.
Production running with NCDs expected by summer. Run with
D2O until Dec. 31, 2006.
Improved precision on 12, 13, sterile neutrinos, hep, matter-enhancement effects…
The SNO Collaboration
T. Kutter, C.W. Nally, S.M. Oser, C.E. WalthamUniversity of British Columbia
J. Boger, R.L. Hahn, R. Lange, M. YehBrookhaven National Laboratory
A.Bellerive, X. Dai, F. Dalnoki-Veress, R.S. Dosanjh, D.R. Grant, C.K. Hargrove, R.J. Hemingway, I. Levine, C. Mifflin, E. Rollin,
O. Simard, D. Sinclair, N. Starinsky, G. Tesic, D. WallerCarleton University
P. Jagam, H. Labranche, J. Law, I.T. Lawson, B.G. Nickel, R.W. Ollerhead, J.J. Simpson
University of Guelph
J. Farine, F. Fleurot, E.D. Hallman, S. Luoma, M.H. Schwendener, R. Tafirout, C.J. Virtue
Laurentian University
Y.D. Chan, X. Chen, K.M. Heeger, K.T. Lesko, A.D. Marino, E.B. Norman, C.E. Okada, A.W.P. Poon,
S.S.E. Rosendahl, R.G. StokstadLawrence Berkeley National Laboratory
M.G. Boulay, T.J. Bowles, S.J. Brice, M.R. Dragowsky, S.R. Elliott, M.M. Fowler, A.S. Hamer, J. Heise, A. Hime,
G.G. Miller, R.G. Van de Water, J.B. Wilhelmy, J.M. WoutersLos Alamos National Laboratory
S.D. Biller, M.G. Bowler, B.T. Cleveland, G. Doucas, J.A. Dunmore, H. Fergani, K. Frame, N.A. Jelley, S. Majerus,
G. McGregor, S.J.M. Peeters, C.J. Sims, M. Thorman, H. Wan Chan Tseung, N. West, J.R. Wilson, K. Zuber
Oxford University
E.W. Beier, M. Dunford, W.J. Heintzelman, C.C.M. Kyba, N. McCauley, V.L. Rusu, R. Van Berg
University of Pennsylvania
S.N. Ahmed, M. Chen, F.A. Duncan, E.D. Earle, B.G. Fulsom,H.C. Evans, G.T. Ewan, K. Graham, A.L. Hallin, W.B. Handler,
P.J. Harvey, M.S. Kos, A.V. Krumins, J.R. Leslie, R. MacLellan, H.B. Mak, J. Maneira, A.B. McDonald, B.A. Moffat,
A.J. Noble, C.V. Ouellet, B.C. Robertson, P. Skensved, M. Thomas, Y.Takeuchi
Queen’s University
D.L. WarkRutherford Laboratory and University of Sussex
R.L. HelmerTRIUMF
A.E. Anthony, J.C. Hall, J.R. KleinUniversity of Texas at Austin
T.V. Bullard, G.A. Cox, P.J. Doe, C.A. Duba, J.A. Formaggio, N. Gagnon, R. Hazama, M.A. Howe, S. McGee,
K.K.S. Miknaitis, N.S. Oblath, J.L. Orrell, R.G.H. Robertson, M.W.E. Smith, L.C. Stonehill, B.L. Wall, J.F. Wilkerson
University of Washington
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Total Active 8B Fluxes
In units of Bahcall, Pinsonneault, Basu SSM, 5.05 x 106 cm-2 s-1
BPB01 SSM 1.00+0.20-0.16
Junghans et al. nucl-ex/0308003
1.16 ± 0.16
SNO D20
(constrained)
1.01 ± 0.13
SNO Salt
(unconstrained)
1.03 ± 0.09
49Time after muon, s
Co
unt
s p
er
seco
nd
N. Oblath
50
16N in D2OC
ou
nts
pe
r s
A.D. Marino
51
(,n) Reactions
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BOREXINO: radiopurity requirements
~ 70 Bq / m3 in PC (0.3ev/day/100tons)
~ 10Bq / m3 in air222Rn
0.160.16Bq/mBq/m3 3 (0.5 (0.5 Bq/mBq/m3 3 ) in N) in N22
0.01 events/day/ton
1.1Bq/m3
(13mBq/m3 ) in air
85Kr, (39Ar)
<10-13g/g(PC) ~ 1ppm in dustKnat
~10-16g/g(PC) ~ 1ppm in dust
~ 1ppb stainless steel
~ 1ppt IV nylon
238U, 232Th
14C/ 12C~10-1814C/ 12C<10-12 14C
Borexino levelTypical
Conc.
If secular equilibrium is broken: contaminants such as 210Pb, 210Po may be a serious problem
53
CC, ES, and NC fluxes from Pure D2O Phase
Shape of 8B spectrum in CC and ES not constrained:
Standard (Ortiz et al.) shape of 8B spectrum in CC and ES:
54
Salt Phase: “Box” Opened Aug. 13, 2003
Shape of 8B spectrum in CC and ES not constrained:
Standard (Ortiz et al.) shape of 8B spectrum in CC and ES: