International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05
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
1. Extruded Plastic Scintillator
2. Current R&D Status
3. Summary of R & D so far
4. Application to Far Detector
5. Summary & Conclusion
Contents
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
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
Extruded Plastic Scintillator
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
Faster energy transfer
Emit UV ~340nm
Absorb UV photon
Emit blue ~400nm
10-8 m
10-4 m photon
photon
Detector (PMT, photo diode …. )
Base plastic
PPO (~1%)
POPOP(~0.05%)
Use WLS fibers as readout
International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05
Die and Materials Die profile
Mixture of dopants Polystyrene : 100% PPO : from 1.0 % POPOP : from 0.03%
• This was originally for MINOS tile
• We start to produce this tile for a reference
• produce and compare the light yield with reference tile
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 produced with 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
Referencesamples
Polystyrene(only) bar 1st batch
Oxidation made the sample opaquebecause of production in air.
Recent 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
Scintillator test setup
Typical cosmic ray From reference sample + WLS
FAN IN-OUT
Logicunit
Gate Generator
100 ns
Delay
VME readout
Disc
5 reference samples and new samples with the same geometrical shape and size were used to compare the light yield
International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05
products of LG and Dongbu chemical company
totally about 10 polystyrenes tested
chose LG 25 E (the best attenuation length etc..)
Polystyrene only
Attenuation Length
0.00
5.00
10.00
15.00
20.00
25.00
4 8 12 16 20
[cm]
Curre
nt[μ
A]
DongbuLG 25 ILG 20 HLG 25 E
International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05
Pulse Height (1st batch)
Our scintillator bars (5 samples)<ADC counts> = 225.9 24.9
Reference scintillator bars(5 samples)<ADC counts> = 534.8 56.9
Relative Light Yield of the first samplesshows 42.3% of reference samples
Our sample(1st batch)
Reference sample
ADC counts
ADC counts
International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05
Light Yield
0
1
2
3
4
5
6
7
0 2 4 6
Sample #
Curr
ent[
μA]
MINOS507075080750809A50809B50810A50810B50813A50817AProgress
0%
20%
40%
60%
80%
100%
0 2 4 6
Sample #
Relat
ive L
Y
507075080750809A50809B50810A50810B50813A50817A
Reference tile to be 100% light yieldRelative Light Yield
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.
0
1
2
3
4
5
6
7
0 2 4 6
Sample #
Cur
rent
[μA
]
50817AMinos5.76 5.35
International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05
Position Scan
0
1
2
3
4
5
6
7
- 40 - 20 0 20 40
Distance [mm]
Curr
ent[
μA
]
Minos 1
Minos 3
Minos 6
Minos 6
Minos 9
K 1
K 3
K 4
K 5
K 6
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 Misung company
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
e
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
15m
6cm
6cm
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
itemtotal weight
(kg)cost($)
Polystyrene 26721900 43554391
PPO 270000 38830297
POPOP 8100 5280920
TiO2 and fiber etc
sum ~ 27kT ~ 87M
1. Scintillator & Fiber : $ 87M
2. Electronics and DAQ : $ 8M
3. Building & outfitting etc.. : $20M
4. Total cost : ~ $114M
Scintillator costs• Very rough estimates• Need more studies
International Workshop on a Far Detector in Korea for theJ-PARC Neutrino Beam, KIAS, Nov 18-19, ‘05
will start R & D for this far detector
Plastic scintillator option may also be feasible
scintillator R & D will go on as it scheduled
Summary
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
15m
15mScintillator Bar
2cm thick Fe