1. DOE/SC Status Review of 12 GeV SHMS HB Magnet: Update since Oct 2015
Eric Sun
Paul Brindza
Steve Lassiter
Mike Fowler
October 25-26, 2016

2. Outline Overview Key Parameters Three-stage Test Plan
Test Results of Stage 3
Magnetic Field Mapping
Conclusion

3. Cryogenic control reservoir
SHMS Q1 beam cutout
Front opening
HB beam cutout
Vacuum vessel
Warm iron
Suspension link

4. Key Parameters of HB Parameter Unit Design Value 11 GeV current A 3900
Test current
4000
Pole Gap (warm) mm
350
Number of turns per pole
turn 90
Stored energy at 3900 A MJ
0.19
Field at 3900 A (11 GeV) T
2.5
Max field in coil at 3900 A
3.2
Self-inductance at 3900 A H
0.025
Current density at 3900 A
A/mm2
22.5
Overall physical length of magnet m
1.16
Magnet weight
ton
6.8
Length of SSC cable in each coil
234.4
Total helium volume in magnet and CCR m3
0.118
Insulation thickness between turns
0.28
Cross section of coil
mm×mm
13.3×130
Cross-section of SSC cable
11.68×1.156
Cu:NbTi ratio of SSC cable
1.8
Dump resistor (final) 
0.024
Effective field length
770
Integral field strength at 3900 A
Tm
1.97
Set pressure of relief valves (He and N2)
atm (gauge) 4
Set pressure of rupture discs (He and N2) 5

5. Eddy Current on Thermal Shield
T6 is a temperature sensor, which can be used to correlate simulations and measurements.

6. Three-Stage Test Plan First Stage – low current tests (up to ~400 A)
Low dump resistor and warm (218 K) thermal shield lead to less eddy current and thus less displacement and stress due to Lorentz force.
Second Stage – medium current tests (up to 2000 A)
Projected displacement and stress were acceptable at 4000 A if a 0.24 ohm dump resistor and a warm (218 K) thermal shield were used.
Third Stage – high current tests (up to 4000 A)
Successful ramped up to 4000 A and fast discharged from 4000 A.
Behaved normally after multiple fast discharges from high currents.
Measured and simulated temperatures matched well.

7. Test Results of Third Stage
Measured (based on T6) vs simulated average temperature rises.
The dashed line, the simulated temperature at T6; the solid line, the measured.
218 K thermal shield and ohm dump resistor.

8. Training Curve
HB magnet was able to reach 3900 A or 4000 A for the last six ramp-ups.
No scope was wired for Event 42. But it was believed Event 42 was caused by PSU.

9. Magnetic Field Mapping - Equipment
LakeShore XHGT-9060 hall probe was used.
Hall probe was manually moved.

10. Magnetic Field Mapping – Results (3900 A)
Measured (blocks) and simulated (solid red line) magnetic field along the central tube.
The measured field at Location 27 was 2.53 T; the Tosca-simulated field, 2.54 T.

11. Conclusion
HB Magnet was successfully ramped up to 4000 A and safely fast discharged from 4000 A.
HB magnet was well trained now.
Measured and simulated magnetic fields match well.
HB magnet is done!