Target & Capture for PRISM
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Target & Capture for PRISM Koji Yoshimura Institute of Particle and Nuclear Science High Energy Accelerator Research Organization (KEK)
description
Target & Capture for PRISM. Koji Yoshimura Institute of Particle and Nuclear Science High Energy Accelerator Research Organization (KEK). Contents. Targetry for PRISM Solenoid capture Conducting Target Summary. What’s PRISM. PRISM ( P hase R otation I ntense S low M uon source) - PowerPoint PPT Presentation
Transcript of Target & Capture for PRISM
Target & Capture for PRISM
Koji Yoshimura
Institute of Particle and Nuclear ScienceHigh Energy Accelerator Research Organization
(KEK)
NufactJ03May 16-17, 2003, TMU
Contents
Targetry for PRISM Solenoid capture Conducting Target Summary
NufactJ03May 16-17, 2003, TMU
What’s PRISM PRISM( Phase Rotation Intense Slow
Muon source)
A dedicated secondary muon beam channel with high intensity (1011~1012/s)and
narrow energy spread(a few%) for stopped muon experiments
Pion Capture
FFAG PhaseRotator
NufactJ03May 16-17, 2003, TMU
Requirements of the Target for PRISM Pion Momentum
~100 MeV/c backwards capture sheme available!
Emittance As low as FFAG acceptance
horizontal 10000vertical 3000 Method
Solenoidal Capture Conducting Target
NufactJ03May 16-17, 2003, TMU
Solenoidal Capture Capture Maching section Decay section Emittance
B field
B（ T)
R(m)
π
π
€
∝
NufactJ03May 16-17, 2003, TMU
Simulation Setup Simulation code
MARS, GEANT3 12 T field -> 3T
47MeV/c ~ 85 MeV/c Backward 2000 ~ 3000 vertical ac
ceptanceproton
~10 cm
B(high) typ. : 16T
B(low) typ. : 4T
field matching region
B
target(tungsten : 2~3 Interaction Length)
~0.1 radian
Shielding Material
Shielding Material
B
R > R B /Blow lowhigh high
22
proton
12 T
3 T
NufactJ03May 16-17, 2003, TMU
Simulation Results Target material
W is better than C B field
Determined by Capture field
Target Radius Loss due to hit target Reabsorption
Yield of pion 0.002~0.006 muon/proto
n
DATA Summmary
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Target Length
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diameter of Warm bore
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B field
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Target Radius
NufactJ03May 16-17, 2003, TMU
SC Solenoid in High Rad. Env Thick radiation shield is necessary
Yokoi’s Technote ~100 W Radiation shield of 34 cm in thickne
ss is needed Large bore for absorber
High stored energy Extremely expensive
Design Need precise heat load data Experimental data is necessary!
Absorber
SC Coil
Thickness of Absorber34 cm, 100W
NufactJ03May 16-17, 2003, TMU
Beam experiment with R&D Magnet
Beam test with R&D mag Direct measurement of heat load by
radiation Study behavior of magnet under hea
ting condition R&D Magnet
10 T hybrid SC coil Cryo cooler
He free Compact
Y. Kuno, A. Yamamoto KEK PS
12 GeV proton 1011 proton/s
NufactJ03May 16-17, 2003, TMU
Around ’95
NufactJ03May 16-17, 2003, TMU
Target for -Fact in US
NufactJ03May 16-17, 2003, TMU
Comparison
B 12 T 6 T
Useful aperture R 0.05 0.10
Cryost. IR 0.55 0.65
Coil IR 0.65 0.75
Coil mean R ~0.85 ~0.83
Coil OR 1.1 ~0.9
Coil length ~2.0 ~2.0
S/C Nb3Sn/NbTi NibTi
Stored energy ~250 MJ ~60 MJ
Coil mass ~50 Ton 10 Ton
Cost (Estimate) 20 M$ 7.8 M$
NufactJ03May 16-17, 2003, TMU
REALISM
Baseline option B=6T Φ=800mm, L=1200 Graphite Target L=2λ=800mm Still Need R&D
~500 W heat is deposited in SC coil Quench protection Radiation safety
NufactJ03May 16-17, 2003, TMU
R&D Plan
Cooling Method ~500W Pool boiling Thermo siphon (Using convection)
R&D Coil will be constructed this year Half or Quarter size Heating using AC LOSS Or Special heater
Engineering Design -> Future Upgade
NufactJ03May 16-17, 2003, TMU
Conducting Target Confine pions inside the target wit
h troidal field B. Autin, @Nufact01
Advantage over Solenoid Low emittance beam Linear transport element
No SC solenoid channel Cheaper!
Cooling condition better?
NufactJ03May 16-17, 2003, TMU
Basic Priciple
€
B∝ r(Inside the target)
Proton
Acceptance
NufactJ03May 16-17, 2003, TMU
Comparison of target material
Mercury is good candidate Minimum Power Easy to cooling Higher pion yield
Technical Issues How to cut off electrical circuit? Container
Shockwave Cavitation Thicker wall can be used!
No reabsorption
NufactJ03May 16-17, 2003, TMU
Setup for current test
1st phase 1000 A DC 100 J
2nd phase 250 KA 2.5ms Pulse (K2K
horn PS) 15 KW
3rd phase 1 MW? Beam test?
NufactJ03May 16-17, 2003, TMU
Mercury Test Loop
Mercury 18 litter ~ 250 kg Study mercury flow
NufactJ03May 16-17, 2003, TMU
Summary
Solenoidal Capture Standard scheme Beam test was successfully performed using the mockup Design parameters will be considered. Realistic R&D Model coil
Conducting Target Lot of merits R&D Work has just started!
Proof of principle Feasibility test of High current liquid target
