Upload
abel-hammond
View
27
Download
2
Embed Size (px)
DESCRIPTION
Reactor Q 13 in the USA. Will discuss Physics case for a “medium” sin 2 2 q 13 ≤ 0.01 reactor experiment. Status of “Midwest” q 13 project at Braidwood, Illinois. Will not discuss Highly advanced, but regrettably suspended Diablo Canyon project. - PowerPoint PPT Presentation
Citation preview
July 28, 2004 Tim BoltonNUFACT 2004-- OSAKA
1
Reactor 13 in the USAWill discuss
Physics case for a “medium” sin2213≤0.01 reactor experiment.
Status of “Midwest” 13 project at Braidwood, Illinois.
Will not discuss
Highly advanced, but regrettably suspended Diablo Canyon project.
American involvement in Double-Chooz, Daya Bay, KASKA, and other international efforts beyond US borders.
US political situation, reactor or otherwise.
July 28, 2004 Tim BoltonNUFACT 2004-- OSAKA
2
Physics Case for sin2213≤0.01Reactor-only:
Uniquely clean and precise measurement of 13.
Medium Braidwood style experiment exploits both rate and shape.
Reactor+T2K/Noa (M. Shaevitz)
Medium experiment resolves (45±23)° degeneracy for 23.
Small D-Chooz type experiment may leave ambiguity.
But for T2K/Noa with + running:
Minimal impact on mass hierarchy from reactors.
Modest impact on CP violation from reactors.
Caveat: A D-Chooz null result would make this physics tough for everybody.Huber et al.
hep-ph/0303232
July 28, 2004 Tim BoltonNUFACT 2004-- OSAKA
3
M. Shaevitz Study:
sin2213(true)=0 sin2213(true)=0.05
Reactors get 13!
July 28, 2004 Tim BoltonNUFACT 2004-- OSAKA
4
23 45 deg. reflection degeneracy
1.5% sin2223
Medium Braidwood-like reactor + / off-axis resolves ambiguity.
Result holds even without high precision 23.
D-Chooz may leave degenerate solutions, even with precise 23.
July 28, 2004 Tim BoltonNUFACT 2004-- OSAKA
5
Precision MeV Physics
104 105 e interactions in near detector precision!
e.g.: RJ ee ee ep e n
(J. Conrad, et al.)
Robust observable, first order flux cancellation.
Addresses “NuTeV anomaly” at NuTeV precision.
Interesting EW tests (ST plane) at Q2=0.
Challenging singles measurement, needs:
•Depth to suppress spallation.
•Borexino-level radioactivity.
•Use of low background energy window.
•≤ 1% systematics (calibrations).
July 28, 2004 Tim BoltonNUFACT 2004-- OSAKA
6
Braidwood Experiment Details
People.
Location.
Layout.
Detectors.
R&D.
Schedule.
July 28, 2004 Tim BoltonNUFACT 2004-- OSAKA
7
ANL: M. Goodman, V. Guarino, D. Reyna
Chicago: E. Abouzaid, K. Anderson, E. Blucher, J. Pilcher, M. Worcester
Columbia: J. Conrad, J. Link, M. Shaevitz
FNAL: L. Bartoszek, D. Finley, H. Jostlein, C. Laughton, R. Stefanski
Kansas State: T. Bolton, J. Foster, G. Horton-Smith, D. Onoprienko, N. Stanton
Michigan: B. Roe
Oxford: S. Biller, N. Jelley
Pittsburgh: D. Naples, V. Paolone
Texas: J. Klein
Midwest 13 Collaboration
July 28, 2004 Tim BoltonNUFACT 2004-- OSAKA
8
Location<50 km from two US national labs: Fermilab + Argonne National Lab.
ANL has ~50 years of reactor expertise.
July 28, 2004 Tim BoltonNUFACT 2004-- OSAKA
9
Reactor Complex
But:
Cost risk associated with “green field” site.
Reactor managment presently encouraging, but tough decisions lie ahead.
July 28, 2004 Tim BoltonNUFACT 2004-- OSAKA
10
Basic Scheme
One near detector at ~270m; at least two far detectors at ~1700m.
Near and far detectors at 450 mwe depth (if bore hole samples confirm).
Identical 6.5m diameter 3-zone (a la D-Chooz) spheres.
Gd-loaded LS fiducial in 25-50 ton range, depending on buffer optimization.
LS -catcher + non-scintillating buffer.
Passive and active external shielding.
Detectors fully constructed at surface sites.
Detectors lowered down shafts (a la KASKA).
Detectors movable via surface transport for cross calibration.
July 28, 2004 Tim BoltonNUFACT 2004-- OSAKA
11
Layout Schematic
Note: reactor management has agreed to shorten near access tunnel length from 300m to 50m ($$$!).
July 28, 2004 Tim BoltonNUFACT 2004-- OSAKA
12
Aerial View
July 28, 2004 Tim BoltonNUFACT 2004-- OSAKA
13
Mechanical Conceptual Design
Lifting points allow full assembly at surface.
Permits far detectors to move to near site for cross calibration.
July 28, 2004 Tim BoltonNUFACT 2004-- OSAKA
14
“Hoist and Roll” Scheme
“Common” procedure in industry.
Considerably cheaper than tunneling.
Favorable terrain at Braidwood site using truck on gravel road or rails, depending on load stresses.
Clearly requires careful design/implementation studies (underway).
Left: 750 ton test lift by crawler crane.
Right: 200 ton drilling equipment on gantry + self-propelled platform trailer. (ALE Lastra).
July 28, 2004 Tim BoltonNUFACT 2004-- OSAKA
15
Hall Layout
July 28, 2004 Tim BoltonNUFACT 2004-- OSAKA
16
July 28, 2004 Tim BoltonNUFACT 2004-- OSAKA
17
Acrylic Sphere Support
Multiple <2.5 cm dia. Spacers.
Assumes simultaneous filling for neutral buoyancy.
Ongoing work at ANL, U. Chicago.
July 28, 2004 Tim BoltonNUFACT 2004-- OSAKA
18
Software
Parametric and full G4 hit-level simulations (D. Onoprienko).
Good agreement with Chooz measurements (after some pain).
Optimizing geometry (RFID vs. R-C vs. RBUF).
July 28, 2004 Tim BoltonNUFACT 2004-- OSAKA
19
Cost/Schedule Detailed estimate prepared for underground construction at Braidwood site prepared by independent consultants (Hilton and Associates, Inc.).
Included civil construction; outfitting with pumps; elevators, ventilation, etc.; and decommissioning costs at experiment end.
Permanent surface structures, detectors not yet included.
Detail level sufficient for re-scaling to optimized layouts.
•First iteration: two 300 mwe shafts, different detector hall designs, 300m tunnel for near site access:
$35M cost, 39 month construction schedule.
•Revised layout: considerably shortened near access tunnel, 450 mwe depth (160m rock+20m soil).
Cost in $25-35M range, <24 month construction schedule.
Detector cost (from MiniBoone scaling) ~ $8M/detector.
July 28, 2004 Tim BoltonNUFACT 2004-- OSAKA
20
Summary
Compelling physics case for a sin2213≤0.01 experiment.
•Medium scale reactor best short-term choice.
•Importantly extends Double-Chooz capabilities (provide ~3×better sin2213 sensitivity; with LBL, resolve 23 45 degree reflection degeneracy; open new field of precision MeV physics.)
Braidwood site an attractive choice:
•High power modern reactor complex with cooperative management.
•Simple layout with deep near site and possibility of movable detectors.
•Access to national lab infrastructure.
Current status:
•Active lab + university-based R&D.
•Bore hole study at Braidwood soon that follows up detailed costing studies.
•Preparing R&D proposal this Fall towards full proposal in 2005.