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Where do we find SNO in April?

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.

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Where do we find SNO in April?

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  1. Where do we find SNO in April? Hamish Robertson Kubodera Festschrift April, 2004

  2. Sudbury Neutrino Observatory 1000 tonnes D2O Support Structure for 9500 PMTs, 60% coverage 12 m Diameter Acrylic Vessel 1700 tonnes Inner Shielding H2O 5300 tonnes Outer Shield H2O Urylon Liner and Radon Seal

  3. Heavy Water from Bruce Plant

  4. n +  + + - CC d p e e n +  + + n NC d p n x x ES - - +  + n e n e x x  Reactions in SNO p • Gives ne energy spectrum well • Weak direction sensitivity 1-1/3cos(q) • ne only. • Measure total 8B n flux from the sun. • Equal cross section for all n types • Low Statistics • Mainly sensitive to ne,, some • sensitivity to n and n • Strong direction sensitivity

  5. Neutrino-deuteron interactions Effective Field Theory EFT (pionless) Standard Nuclear Physics Approach (SNPA): Potential model Higher-order corrections with mesons, ’s Precision numerical calculation Expansion of interactions in power series. Scattering length a, deuteron binding g, 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)

  6. Depend on L1A 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

  7. L1A can be fit to SNPA calculations EFT SNPA A SINGLE choice of L1A produces this agreement!

  8. EFT/SNPA - - CC - MeV - NC EFT compared to Standard Nuclear Physics Approach Ratio of Butler et al. (BCK) EFT with L1A = 4.0 fm3 to Nakamura et al. (NSA+)

  9. BP04: 5.79 (1 0.23) Neutrino Flavor Composition of 8B Flux Fluxes (106 cm-2 s-1) ne: 1.76(11) nmt: 3.41(66) ntotal: 5.09(64) nSSM: 5.05 Shape-constrained fits. Pure D2O data. PRL 89, 011301, 2002

  10. L1A = 4.0 L1A = 20 ES

  11. Determinations of L1A

  12. Total spectrum (NC + CC + ES)

  13. Less than Maximal Mixing at 3 s Best Fit Dm2 = 6.2 x 10-5 eV2 tan2q = 0.40 Flux/SSM = 1.06 SOLAR LMA 3s Bounds Dm2 < 3.3 x 10-4 tan2q < 0.80 tan2Q < 1 implies m2 > m1 de Holanda and Smirnov hep-ph/0205241

  14. tan2q12-Dm122 Solar Only Solar+KL rate Solar+KL spect. de Holanda & Smirnov, hep-ph/0205241, hep-ph/0212270

  15. g n 36Cl* 36Cl 35Cl Advantages of NaCl for Neutron Detection • Higher capture cross section • Higher energy release • Many gammas s = 44 b 35Cl+n s = 0.0005 b 8.6 MeV 2H+n 6.0 MeV 3H 36Cl

  16. Neutron Capture Efficiency in SNO 35Cl(n,g)36Cl Average Eff. = 0.399 Te≥ 5.5 MeV and Rg ≤ 550 cm 2H(n,g)3H Average Eff. = 0.144 Te≥ 5.0 MeV and Rg ≤ 550 cm Radial Position of 252Cf Source, cm

  17. Charged particle, v > c/n Hollow cone of emitted photons qij 43o ) Energy & Direction Water b14 = b1 + 4b4 Cherenkov light and b14

  18. Use of b14 to distinguish neutrons and e-

  19. Addition of Mott scattering to EGS4 Angular Distribution of 5 MeV electrons after passing through ~1 mm of water

  20. 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

  21. b14 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

  22. Sun-angle distributions Away from sun Toward sun

  23. Energy spectra Electron kinetic energy

  24. Radioassay • Bottom of vessel • 2/3 way up • Top of vessel • MnOx • HTiO • MnOx • HTiO

  25. Salt Phase: “Box” Opened Aug. 13, 2003 Shape of 8B spectrum in CC and ES not constrained: Salt Phase Standard (Ortiz et al.) shape of 8B spectrum in CC and ES: Pure D2O Phase

  26. tan2q12-Dm122 before Salt Phase Solar Only Solar+KL rate Solar+KL spect. de Holanda & Smirnov, hep-ph/0205241, hep-ph/0212270

  27. From the Salt Phase… Ratio:

  28. Closing in on Dm2, q --90% --95% --99% --99.73% LMA I only at > 99% CL

  29. Results from SNO -- Salt Phase Oscillation Parameters, 2-D joint 1-s boundary LMA II rejected at >99% CL Marginalized 1-D 1-s errors Maximal mixing rejected at 5.4 s A paper plus a “companion” guide can be found at sno.phy.queensu.ca Accepted (at last!) by PRL; nucl-ex/0309004.

  30. Solar n2 n1 ? ? Neutrino Masses and Flavor Content Mass (eV) emutau Atmospheric 0.048 n3 Solar n2 0.040 n1 0.039 0.008 Atmospheric =0 =0 n3 0

  31. Cosmological Implications  neutrino masses:0.048 < m1+m2+m3 < 6.6 eV  Laboratorylimit onnfraction of universe closure density: Large-scale structurelimit : • 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

  32. B. Cabrera, 2004

  33. SNO Phase III (NCD Phase)- Begins ‘04 x n • 3He Proportional Counters (“NC Detectors”) 40 Strings on 1-m grid 398 m total active length 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 PMT NCD Physics Motivation Improved NC, NC/CC: q12 CC spectral shape: MSW, Dm2

  34. Why Event-by-Event? Analyst: A. Hime

  35. Breakingthe Correlation J. Manor, M. Smith

  36. 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.

  37. Lowering a welded string and its electrical cable

  38. Flying the ROV to the string’s anchor position.

  39. Installed 3He Counter Strings 3He 4He N

  40. 764 keV AmBe Source Jan. 13, 2004 Spectrum of 3He(n,p)3H in K6 string Counts per channel Channel

  41. Where do we find SNO in April? Improved precision on q12, q13, sterile neutrinos, hep, matter-enhancement effects… 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.

  42. The SNO Collaboration 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. Wark Rutherford Laboratory and University of Sussex R.L. Helmer TRIUMF A.E. Anthony, J.C. Hall, J.R. Klein University 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 T. Kutter, C.W. Nally, S.M. Oser, C.E. Waltham University of British Columbia J. Boger, R.L. Hahn, R. Lange, M. Yeh Brookhaven 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. Waller Carleton 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. Stokstad Lawrence 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. Wouters Los Alamos National Laboratory

  43. Total Active 8B Fluxes In units of Bahcall, Pinsonneault, Basu SSM, 5.05 x 106 cm-2 s-1

  44. Counts per second N. Oblath Time after muon, s

  45. 16N in D2O Counts per s A.D. Marino

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