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Detector with Plastic Scintillators. DongHee Kim Kyungpook National University. Contents. Extruded Plastic Scintillator 2. Current R&D Status 3. Summary of R & D so far 4. Application to Far Detector 5. Summary & Conclusion. Extruded Scintillator. Comparing with Casting method:
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Detector with Plastic Scintillators DongHee Kim Kyungpook National University International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05
Contents • Extruded Plastic Scintillator 2. Current R&D Status 3. Summary of R & D so far 4. Application to Far Detector 5. Summary & Conclusion International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05
Extruded Scintillator • Comparing with Casting method: • Use commercial polystyrene pellets → Cheap ! • Processing flexibility → Manufacture of essentially any shape with reflector. • Experimental applications: • MINOS for two detectors: 300 ton of scintillator strips • D0 for two preshower detectors • Star for a shower max. detector in the em. end-cap calorimeter • MINERVA • K2K – SciBar detector • And more …many applications for your future detectors International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05
Extruded Plastic Scintillator • Component: Polystyrene pellets + Dopants (primary & secondary) • Dopants • Primary dopants (UV-emitting) • PPO(2,5-biphenyloxazole) , PT(p-Teraphenyl) • 1-1.5% (by weight) concentration • Secondary dopants (blue-emitting) • POPOP(1,4-bis(5-Phenyloxazole-2-yl)benzene), • bis-MSB(4-bis(2-Methylstyryl)benzene) 0.01-0.03% (by weight) concentration International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05
Plastic Scintillator – how does it work ? Excitation of base plastic by radiation Base plastic 10-8 m Faster energy transfer PPO (~1%) Emit UV ~340nm photon 10-4 m Absorb UV photon POPOP(~0.05%) Emit blue ~400nm photon Use WLS fibers as readout Detector (PMT, photo diode …. ) International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05
Die and Materials • Die profile • This was originally for MINOS tile • We start to produce this tile for a reference • produce and compare the light yield with reference tile • Mixture of dopants Polystyrene : 100% PPO : from 1.0 % POPOP : from 0.03% International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05
Extrusion Process Produced at MiSung Chem. co. In Korea International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05
Current R&D Status • The pure polystyrene bar was produced (w/o PPO, POPOP) • The mechanical process has been established and choose the best polystyrene • PPO and POPOP were mixed up with polystyrene • The 1st scintillator had been produced. • Many scintillator strips have been producedwith different situations since then. • different amount of PPO and POPOP, nitrogen and/or vacuum, • various mix-up methods etc. International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05
Mechanical establishment of tile • Produce polystyrene bar without PPO & POPOP for mechanical establishment • TiO2 was co-extruded to make reflector for test. • Excellent bars were produced assure mechanically • Then, 1st batch came with PPO and POPOP. Progress International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05
Production of Scintillator bar International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05
Comparison of transparency Oxidation made the sample opaque because of production in air. Reference samples Polystyrene (only) bar Recentbatch 1st batch Progress International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05
Preparation of test samples WLS fiber International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05
FAN IN-OUT Disc Logic unit Gate Generator 100 ns Delay VME readout Scintillator test setup • 5 reference samples and new samples with the same geometrical shape and size were used to compare the light yield Typical cosmic ray From reference sample + WLS International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05
Polystyrene only • products of LG and Dongbu chemical company • totally about 10 polystyrenes tested • chose LG 25 E • (the best attenuation length etc..) International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05
Pulse Height (1st batch) Our sample(1st batch) Our scintillator bars (5 samples) <ADC counts> = 225.9 24.9 Reference scintillator bars(5 samples) <ADC counts> = 534.8 56.9 ADC counts Reference sample Relative Light Yield of the first samples shows 42.3% of reference samples International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05 ADC counts
Light Yield Relative Light Yield Reference tile to be 100% light yield Progress Progress International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05
Light Yield (currently the best one) Reference Sample New Sample Relative Light Yield of new samples shows (93±8)% of reference samples’ one. International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05
Position Scan Scan across the fiber International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05
Summary of R & D so far • First Polystyrene bar produced with PPO and POPOP The mechanical process has been established • Light yield measured for new and reference samples Currently the best samples show (93±8) % light yield • Of course, need much more R & D in the future • improving attenuation length, light yield, uniformity and radiation hardness etc.. • Fiber(WLS and clear) will be also R & Ded in the Misungcompany • We can apply this to the detectors • The LHC and LC … calorimeters • Neutrino LB Experiments • Reactor experiments etc…. International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05
Application to the Far Detector • For appearance experiment • Totally active is appropriate • Nova already chose liquid scintillator option • Here we consider the plastic scintillator option • Reference from Nova proposal – Thanks for them! • Nova adopted Liquid scintillator option International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05
Application to the Far Detector • Total Plastic Scintillator Calorimeter • all active absorber • 300 X0 depth • ~ 2000 Layers • each layer : 15m x 15m • 27kT plastic scintillator • one bar : 6cm x 6cm x 15m • 250 bars/layer • x-y positioning every other layer • Total ~ 500k channels 120m 15m 6cm 6cm 15m International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05
Scintillator Bar • Polystyrene + PPO + POPOP • 2mm WLS Fiber embedded in the bar • Light Reflector(TiO2) • readout both ends by APD(or SiPM??) • need about 1M APDs • Ensure enough light yields • with 2mm WLS fiber (4time better light collection compared with 1mm fiber) and Both end readout International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05
Cost Estimates • Scintillator & Fiber : $ 87M • Electronics and DAQ : $ 8M • Building & outfitting etc.. : $20M • Total cost : ~ $114M • Very rough estimates • Need more studies Scintillator costs International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05
Summary • will start R & D for this far detector • Plastic scintillator option may also be feasible • scintillator R & D will go on as it scheduled International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05
Backup International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05
Application to the Far Detector • Option B : • Sampling Calorimeter • Scintillator/Fe Sandwitch • 300 X0 depth • ~ 230 Layers • each layer : 15m x 15m • Iron 15m x 15m x 2cm • Iron 2cm = 1.14 X0 • 8kT iron • 3.1kT plastic scintillator • one strip: 6cm x 6cm x 15m • 250 strips/layer • x-y positioning every other layer ~20m 2cm thick Fe 15m Scintillator Bar 15m International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05