Where do we find SNO in April?

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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

3

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

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16N in D2OC

ou

nts

pe

r s

A.D. Marino

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(,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

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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:

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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: