Advanced Extruded Scintillator R&D
Alan Bross
2 Alan Bross ANL-UChicago-FNAL CM4 June 26, 2008
Context
The extruded scintillator R&D Program started at Fermilab about 14 years ago
Primary Goal reduce cost using Industrial Techniques for production – Extrusion
Advantages Use commercial polystyrene Manufacture almost any shape Very-High production rates possible LOW COST
Disadvantage Poorer optical quality
– Requires WLS fiber readout Original work utilized extrusion equipment at outside
vendor Their facilities/production techniques certainly not
optimized for high-quality scintillator production
3 Alan Bross ANL-UChicago-FNAL CM4 June 26, 2008
FNAL-NICADD Extrusion Facility
State-of-the-ArtOptimized for Scintillator
Fully automated
4 Alan Bross ANL-UChicago-FNAL CM4 June 26, 2008
FNAL-NICADD EXTRUSION FACILITY
POLYMERDRYER
CONVEYOR
POLYMER FEEDER
DOPANT FEEDER
EXTRUDER
MELT PUMP
DIE
In-line continuous process: Less handling of raw materials Precise metering of feeders Twin-screw extruder (better mixing) Melt pump offers steady output Control instrumentation
5 Alan Bross ANL-UChicago-FNAL CM4 June 26, 2008
Projects
D0 preshower detectors
MINOS
SciBar – K2K/SciBoone Star Mayan Pyramid Mapping
UT-Austin
6 Alan Bross ANL-UChicago-FNAL CM4 June 26, 2008
Projects II
Hall B – JLAB
Minerva
T2K – ND280 Rochester Lancaster Kyoto (Ingrid)
Double-Chooz Amiga – Pierre Auger
7 Alan Bross ANL-UChicago-FNAL CM4 June 26, 2008
Next step in R&D
Potential Process Modifications Run multiple threads
Maximizes throughput of machine Minimizes linear speed of extrusion part exiting die
– Stability/Cooling issues Co-extrude Kuraray fiber with the scintillator profile
Reduce handling of WLS Fiber Co-extrusion
Prototyped with outside vendor some 8 years ago Post-clad Kuraray fiber
Polyethylene Kynar Teflon
No degradation of fiber seen (but thin (100-300 m) coatings
WLS fiber did see large heat excursion, however
8 Alan Bross ANL-UChicago-FNAL CM4 June 26, 2008
Proposal
Develop Co-Extrusion Die Tooling with ISO-9000 qualified Vendor - Guill Tool
They have experience with this type of die Have developed tooling for co-extrusion applications
that involve polymers with different melt characteristics which required pre-cooling of one or more of the components in the extrusion
Melt temperature for scintillator extrusions above the glass transition of the fiber
Much larger heat soak than in our previous tests
9 Alan Bross ANL-UChicago-FNAL CM4 June 26, 2008
Potential Benefits
Extruded scintillator Profiles Readout with WLS Fiber Advantages of co-extrusion
Almost no fiber handling yielding significant manpower cost reduction
Almost perfect scintillator-fiber optical coupling Greater uniformity with respect to light coupling between
the scintillator and WLS fiber Benefits of UC-Fermilab Collaboration
Students and/or postdocs working on the R&D at the facility Note: Since the demise of the Fermilab student COOP program,
we have not had students (other than summer) working in the facility
R&D nature of the facility will be reinvigorated Has become production-only facility in recent years
Will improve the prospects for technical advances yielding a more powerful/cost-effective detector technology
Allow us to Better serve user base
10 Alan Bross ANL-UChicago-FNAL CM4 June 26, 2008
Magnetized Fine-Resolution Totally Active Segmented Detector
Simulation of a Totally Active Scintillating Detector (TASD) using Noa and Minera concepts with Geant4
3 cm
1.5 cm15 m
3333 Modules (X and Y plane) Each plane contains 1000 slabs Total: 6.7M channels
Momenta between 100 MeV/c to 15 GeV/c Magnetic field considered: 0.5 T Reconstructed position resolution ~ 4.5 mm
15 m
15 m
150 m
B = 0.5T
11 Alan Bross ANL-UChicago-FNAL CM4 June 26, 2008
Magnet
New Idea VLHC SC
Transmission Line Technically
proven Might actually
be affordable
1 m iron wall thickness. ~2.4 T peak field in the iron.
Good field uniformity
12 Alan Bross ANL-UChicago-FNAL CM4 June 26, 2008
TASD Performance II
Excellent Momentum resolution (2-4%) Think Big(ger)
Nucleon Decay
P -> + 0