1. Progress on the MICE Cooling Channel Solenoid Magnet System
 M.A. Green, S. Q. Yang,
G. Barr, U. Bravar, J. Cobb  
W. W. Lau, R.S. Senenayake, 
H. Witte, A. E. White
Physics Department, Oxford University, UK
D. Li and S. P. Vorostek
Lawrence Berkeley Laboratory, Berkeley USA

2. Outline Introduction of MICE Cooling Channel
MICE Absorber Focusing Coil module
The Focusing Magnet Design
FEA Models of the Focusing magnet
MICE RF and Coupling Coil module
The Coupling Magnet design
FEA Models of the Coupling Magnet
Tasks Completed and Tasks to Do
Conclusion

3. Focusing and Coupling Magnet Reports
M. A. Green and S. Q. Yang, “Heat Transfer into and within the 4.4 K Region and the 40 K Shields of the MICE Focusing and Coupling Magnets” Oxford University Physics Report, 28 April 2004
M. A. Green and R. S. Senanayake, “The Cold Mass Support System for the
MICE Focusing and Coupling Magnets,” Oxford University Physics Report, 23 August 2004
M. A. Green and S. Q. Yang, “The Coil and Support Structure Stress and Strain the MICE Focusing and Coupling Magnets,” Oxford University Physics Report, 30 August 2004
M. A. Green, “Cooling the MICE Magnets using Small Cryogenic Coolers,” Oxford University Physics Report, 10 September 2004
S. Q Yang, M. A. Green, G. Barr, et al, “The Mechanical and Thermal Design for the MICE Focusing Solenoid Magnet System,” submitted to IEEE Transactions on Applied Superconductivity 15, (2005), submitted 5 Oct. 05
M. A. Green, S. Q. Yang, U. Bravar, et al, ““The Mechanical and Thermal Design for the MICE Coupling Solenoid Magnet,” submitted to IEEE Transactions on Applied Superconductivity 15 (2005), submitted 5 Oct. 05

4. The MICE Cooling Channel
Coupling Coil
Focusing Coil
RF Cavity
Coupling Magnet Cryostat
Focusing Magnet Cryostat
AFC Module

5. Half Section View of the MICE Cooling Channel
Coupling Coil
RF Cavities
Absorber
AFC Module
RF Coupling Module
Coupling Magnet Cryostat
Focusing Coil

6. MICE Focusing Magnet

7. MICE: Absorber Focusing Coil (AFC) module
Cooler
Magnet Vacuum
Absorber Vacuum Door
Coil Mandrel
Hydrogen duct
Absorber Body
Safety Window
S/C Coil 1
LH2 window
S/C Coil 2
Absorber vacuum
Module vacuum vessel
AFC 2D Cross-section
AFC 3D View

8. MICE Focusing Solenoid Cross-section

9. AFC Magnet Cross-section
Focusing Magnet
Cold Mass Support
Magnet Coil and Absorber Cross-section

10. The Basic Parameters of the Focusing Magnet in the Non-flip and the Flip Mode
Coil Separation (mm)
200
Coil Length (mm)
210
Coil Inner Radius (mm)
263
Coil Thickness (mm) 84
Number of Layers 76
No. Turns per Layer
127
Magnet J (A mm-2)*
71.96
138.2
Magnet Current (A)*
130.5
250.7
Magnet Self Inductance (H)
137.4
98.6
Peak Induction in Coil (T)*
5.04
7.67
Magnet Stored Energy (MJ)*
1.17
3.10
4.2 K Temp. Margin (K)*
~2.0
~0.5
Inter-coil Z Force (MN)*
-0.56
3.40
* Design based on p = 240 MeV/c and beta = 420 mm.

11. The Focusing Magnet Load Lines and Conductor Current Versus the Magnetic Induction at Various Conductor T
TM = 0.5 K
TM = 2.0 K

12. Focusing Magnet DT, Cooling along One Line
Local region applied 4.3K
DT = 1.08 K
The focus magnet is attached to the cooler along a 100 mm wide strip that is at 4.3 K.
The radiation heat load on all other surfaces QR = 1.0 W m-2.
The maximum DT = 1.08 K

13. Focusing Magnet DT, Outside Cooling
The heat flux on the inner cylindrical surface and the ends is 1 W m-2; the outer cylindrical surface is at 4.3 K.
The maximum DT = K

14. Magnet connection to the Cooler with a Liquid Helium Cold Pipe
T2 - T1 < 0.1
The superconducting coils for the MICE focus magnets will be cooled by conduction from liquid helium in a space on the outside of the magnet coils. A simple gravity feed heat pipe supplies cold liquid from the helium condenser to the bottom of the magnet. The boil off gas is re-liquefied on a condenser surface and the condense liquid helium is sent back to the bottom of the magnet helium tank

15. Focusing magnet Stress and Deflection due to the Cool Down
The results show the Von Mises Stress, Radial Deflection (negative y direction) and Longitudinal Deflection (z direction) due to cooling the Focusing Magnet Module from Room Temperature to 4.2 K.

16. Focusing magnet Stress and Deflection due to the Cool Down and Magnetic Forces
The results show the von mises stress, the radial (the Y direction) and longitudinal (the Z direction) deflections, for the focusing magnet module that has been cooled from room temperature to 4.2 K, and the coils are powered for as in the baseline full-flip case with a muon beam with an average momentum of 240 MeV/c.

17. MICE Coupling Magnet

18. MICE: RF and Coupling module
Coupling Magnet
Cavity RF Coupler
Dished Be Window
RF Cavity Cell
Module Vacuum Vessel
Vacuum Pump
Magnet Vacuum Vessel
2D view of the RF and Coupling Module
Three quarter section 3D View of RF module

19. MICE Coupling Solenoid Cross-section

20. Relationship of the Coupling Coil to the Cavity
Be Window
Cavity Coupler
201 MHz RF Cavity
Vacuum Pump
The coupling coil length is determined by the position of the RF couplers.

21. The Basic Parameters of the Coupling Magnet in the Non-flip and the Flip Mode
Coil Length (mm)
250
Coil Inner Radius (mm)
725
Coil Thickness (mm)
116
Number of Layers
104
No. Turns per Layer
151
Magnet J (A mm-2)*
104.9
115.5
Magnet Current (A)*
193.6
213.2
Magnet Self Inductance (H)
563
Peak Induction in Coil (T)*
7.09
7.81
Magnet Stored Energy (MJ)*
10.6
12.8
4.2 K Temp. Margin (K)*
~0.9
~0.6
* Design based on p = 240 MeV/c and beta = 420 mm.

22. The Coupling Magnet Load Lines and Conductor Current Versus the Magnetic Induction at Various Conductor T
TM = 0.6 K
TM = 0.9 K

23. entire outside surface a) Cooling at one point on
Temperature Distribution on the Coupling Coil as a Function of Cooling Location
Cooling on the
entire outside surface
QR = 1.0 W m-2
4.3 K
4.568 K
DT = K
a) Cooling at one point on
the outside surface
QR = 1.0 W m-2
4.3 K
DT = K

24. Cooler Circuit for the Coupling Magnet
The heat pipe reduces
T2-T1 to < 0.1 K.
See page 23 for reduction
T3-T2 within the coil.
T3-T0 is ~ 0.2 K
There is no copper strap
between the cooler and
the magnet.

25. Coupling Magnet Stress and Deflection due to the Cool Down and Magnetic Forces
The results show the von Mises stress, the radial (the Y direction) deflection,
for the coupling magnet cooled from 300 K to 4.2 K, and the coils are powered
for the full-flip case with a muon beam with a momentum of 200 MeV/c.

26. Tasks Completed and Tasks to Do
Focusing
Coupling
Basic Coil Design based on a Conductor
Yes
Temperature Distribution in Magnet
Stress and Deflection in Magnet
Cold Mass Support System Design
Cooler Selection and Hook Up Design
Quench Protection System Design
Dec 2004
Engineering Completed for a RFP*
April 2005
June 2005
Specifications for the RFP*
Safety Documentation for RFP*
Sept. 2005
Power Supply Specification*
* Based on developing a performance specification (not build to print)

27. Other Magnet Related Tasks to Do
Complete and check the cold mass support force calculations for all relevant cases. Partly Done
Check the worst cases forces to be encountered during a magnet quench. Partly Done
Determine if a quench of one magnet in MICE can will cause other magnets to quench inductively.
Design the copper current leads from 300 K to 50 K for currents of 300 A and 60 A. Partly Done
Select the 300 A and 50 A HTS leads. Partly Done

28. Conclusions
Most of the relevant design calculations have been done for the focusing and coupling magnets.
Most of the relevant calculations have been done to allow the magnets to be cooled by small coolers.
The 2D and 3D Drawings of the entire channel are beginning to come together.
More work must be done a quench calculations.
The RFP specifications for the magnets and magnet subcomponents need to be written.
The magnets must be looked at for safety hazards.