SNO Intro and Overview

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SNO Intro and Overview Powered By Docstoc

Mark Chen
June 8, 2008
SNO+ is…
   we plan to fill SNO with liquid scintillator
   we also plan to dope the scintillator with
    neodymium to conduct a double beta decay
    measurement (first run is with Nd)
   to do this we need to:
    –   install hold down ropes for the acrylic vessel
    –   buy the liquid scintillator
    –   build a liquid scintillator purification system
    –   minor upgrades to the cover gas
    –   minor upgrades to the DAQ/electronics
    –   change the calibration system and sources
   SNO+ is partially-funded for these activities by
    NSERC and seeks full capital funding in the current
    CFI LEF competition                              2 of 23
SNO+ Physics Program

   search for neutrinoless double beta
   neutrino physics
    – solar neutrinos
    – geo & reactor antineutrinos
    – supernova neutrinos
SNO+ Physics Goals
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Targets for Double Beta
                   1. test the Klapdor
  Klapdor result      claim
                   2. reach the inverse
                   3. beyond the next
                      generation: aim for
                      the normal

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Why 150Nd?
  3.37 MeV endpoint (2nd highest of all  isotopes)
     above most backgrounds from natural radioactivity
  largest phase space factor of all  isotopes
     e.g. factor of 33 greater compared with 76Ge
     for the same effective Majorana neutrino mass, the 0 rate
      in 150Nd is the fastest
  cost of NdCl3 is $86,000 for 1 ton (not expensive)
  upcoming experiments use Ge, Xe, Te; we can deploy a
   large and comparable amount of Nd

How Does 150Nd Compare?
 56 kg of   150
                   Nd is equivalent to:
      0.1% Nd loaded liquid scintillator in SNO+, using natural Nd
 considering only the phase space factor
      ~220 kg of 136Xe
      ~230 kg of 130Te
      ~950 kg of 76Ge
 including QRPA matrix element calculations
      ~1500 kg of 136Xe
      ~400 kg of 130Te
      ~570 kg of 76Ge
                                               thanks L. Simard and F. Piquemal

56 kg of 150Nd and <m> = 100 meV
                       6.4% FWHM at Q-value
                       3 years livetime
                       U, Th at Borexino levels
                       5 sensitivity
                       note: the dominant
                        background is 8B solar
                       214Bi (from radon) is almost
                       212Po-208Tl tag (3 min) might
                        be used to veto 208Tl
                        backgrounds; 212Bi-212Po
                        (300 ns) events constrain
                        the amount of 208Tl

Double Beta Decay Comparisons

              EXO 200


          CUORE 750kg

 SNO+ Estimate:
                  • Natural Nd in 2011 • 50% fiducial volume
                  • Enriched Nd in 2014 • 75% livetime         8
SNO+ Project Funding
   $61.5k from NSERC in 2005-06 for R&D to establish “proof of
   $114k from NSERC in 2006-07 for “Expanded R&D”
   $400k from NSERC in 2007-08 for “Transition Activities and
    Continued Development”
   $1.3M from NSERC in 2008-09 and 2009-10 for “Final Design
    and Initial Construction”
    – also supports HQP, materials, travel, design and engineering
      costs at Queen’s, Laurentian/SNOLAB and Alberta

   SNOLAB EAC officially approved SNO+ for the requested
    space and resources in the lab in 08/2007
    – scientific merit “high” and ready for implementation
   approved as an IPP Project in 01/2008

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Current NSERC Funding
   $1.0M released; $0.3M second installment
    made available after an external
    engineering/technical review of the final AV
    hold down design
   Year 2 funding if the above review is passed
    – $0.8M released; $0.5M second installment if CFI
      funding is approved

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Foreign Funding
   NSF supports ISU group
    – in 2007-08 $113k USD for personnel and travel
    – in 2008-09 $122k USD for personnel and travel
   US DOE groups preparing funding request
    for next year
    – to include a small amount of capital funding for
      DAQ/electronics upgrade
          Penn, Washington

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SNO+ Project Costs and
Funding Strategy
estimated total Canadian costs

NSERC requested share of capital costs: $2.73M

FedNor Innovation Project request is being evaluated: $400k

we will prepare a request to CFI (10/2008) for the remainder
(i.e. whatever doesn’t get funded)

CFI request to include calibration systems, hardware, sources: $0.3M
                                                                   12 of 23
SNO+ AV Hold Down

   AV Support
SNO+ AV Hold Down

   AV Support
                    AV Hold Down
  Robustness of Rope Configurations
rope configuration and loading

 Gaussian perturbation
 2cm sigma on segments
 4cm on anchors

 broken rope in top ring

 max tension 15.4 tonnes.

   AV Hold Down Design Status
• nonlinear buckling and FEA
  analysis completed
   – Vance Strickland (TRIUMF)
   – JRL Consulting
• currently reviewing design
• plan to have Bob Brewer
  approve the design as the
  engineer authority
• have this design subject to an
  external review, as requested
  by NSERC

• have found rope material with
  K, U, Th that meet target
   – Jaret Heise (Idaho State)

AV Hold Down Plans

   once the design is approved and
    reviewed, continue with developing
    the complete installation plan with
    cavity access
   materials procurement delayed until
    later installment of funding from
    NSERC is released

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Scintillator Purification
   prelim design Phase I and Phase IIa completed by
    KMPS (engineering company that designed the
    Borexino scintillator purification)
    – with ±20% cost estimate completed
   sizing completed, operating temperatures and
    pressures, flow rates calculated, performance
   now preparing “process design package” and final,
    fixed price, engineered design (Phase IIb)
    – expanding KMPS scope to include Nd loading and
      purification module and scintillator underground filling
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SNO+ Schedule and Milestones

                           22 of 23
                        SNO+ Collaboration

           University of Alberta:                          University of Pennsylvania:
 R. Hakobyan, A. Hallin, M. Hedayatipoor, C.        E. Beier, H. Deng, W.J. Heintzelman, J. Klein,
               Krauss, C. Ng                                     J. Secrest, T. Sokhair

    Brookhaven National Laboratory:                             Queen's University:
       R. Hahn, Y. Williamson, M. Yeh                M. Boulay, M. Chen, X. Dai, E. Guillian, P.J.
                                                      Harvey, C. Kraus, X. Liu, A. McDonald,
        Idaho National Laboratory:                       H.O’Keeffe, P. Skensved, A. Wright
                    J. Baker
          Idaho State University:                   B. Cleveland, F. Duncan, R. Ford, C.J. Jillings,
J. Heise, K. Keeter, J. Popp, E. Tatar, C. Taylor                     I. Lawson

           Laurentian University:                              University of Sussex:
 E.D. Hallman, S. Korte, A. Labelle, C. Virtue                E. Falk-Harris, S. Peeters

                 LIP Lisbon:                            Technical University of Dresden:
      S. Andringa, N. Barros, J. Maneira                               K. Zuber

             Oxford University:                             University of Washington:
S. Biller, N. Jelley, P. Jones, J. Wilson-Hawke     M. Howe, K. Schnorr, N. Tolich, J. Wilkerson

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• extra slides below

      Acrylic Vessel D2O Loads Compared with Scintillator Loads

                  D2O Condition       Scintillator    Comments
Density                 1.1              0.86        Delta 14% vs
Net Vertical       99.4 Tonnes       120.5 Tonnes    21 % greater
Load                  Down             Buoyant           load
Vertical            120 Tonnes       157 Tonnes
Compressive         (Hydrostatic     (Hydrostatic
Load at Equator    pressure from     pressure of
                  top half pushing    bottom half
                       down)         pushing up)


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