1. GSI Helmholtzzentrum für Schwerionenforschung GmbH The Optimized Superconducting Dipole of SIS100 for Series Production ICEC26 March 9th, 2016 GSI Helmholtzzentrum für Schwerionenforschung GmbH C. Roux et al.

2. GSI Helmholtzzentrum für Schwerionenforschung GmbH Introduction 1.Overview: FAIR, SIS100, dipole module 2.SIS100 Dipoles 1.Basic design 2.First of Series Magnet (FoS) 3.Improvement Strategy 4.First of Series Magnet with New Yoke (FoS-2) Conclusions Outline 2

3. GSI Helmholtzzentrum für Schwerionenforschung GmbH Dipole module Introduction: FAIR, SIS100, dipole 3 Heavy Ion Synchrotron SIS100 core component 100 Tm rigidity 1 s cycle, ( B max = 1,9 T) 1100 m circumference 108 dipoles, 168 quadrupoles, correctors vacuum quality: < 10 -12 mbar

4. GSI Helmholtzzentrum für Schwerionenforschung GmbH SIS100 Dipole: Basic Design NUCLOTRON type magnet: Superferric design Hollow superconducting cable Forced-flow two-phase Helium cooling Cold iron (4 K) Requirements: Maximal field: 1.9 T Ramp rate: 4 T/s (@ 1 Hz) Homogeneity better 6×10 -4 within 57.5 x 30 mm (elliptical) ~ 3 m 4 N S ~ 260 mm s.c. coil ~ 330 mm 1 - Cooling tube CuNi 2 - SC wire NbTi 3 - CrNi wire 4 - Kapton tape 5 - Glasfiber tape Nuclotron cable: iron yoke

5. GSI Helmholtzzentrum für Schwerionenforschung GmbH  First of Series (FoS-1) Production (Middle of 2013)  Testing started in November 2013 SIS100 First of Series Dipole 5 Excellent quench performance Excellent mechanical stability of the coil (alternating quenches in lower and upper poles) Low quench degradation factor no de-training quench performance:

6. GSI Helmholtzzentrum für Schwerionenforschung GmbH SIS100 First of Series Dipole 6 Parametric model: q h = 4.2±0.5 J q e = 6.0±0.2 J ˑ s  First of Series (FoS-1) Production (Middle of 2013)  Testing started in November 2013 ac losses:

7. GSI Helmholtzzentrum für Schwerionenforschung GmbH SIS100 First of Series Dipole 7 However: Magnetic-field quality!  First of Series (FoS-1) Production (Middle of 2013)  Testing started in November 2013

8. GSI Helmholtzzentrum für Schwerionenforschung GmbH Allowed harmonics: accuracy ± 0.2 units Main field: Non-allowed harmonics: z = 0 z = ±300 mm z = ±900 mm R ref = 40 mm NCS Non-allowed harmonics: Rotating coil data FoS-1: Magnetic-Field Integral 8

9. GSI Helmholtzzentrum für Schwerionenforschung GmbH 9 Egbert Fischer et al. / SC Magnets / MAC-14 Gap geometry measurement tools carrier with capacitive sensors (operational at 4 K): carrier with mechanical sensors:

10. GSI Helmholtzzentrum für Schwerionenforschung GmbH Gap height (@ 300 K) Gap width with coil (@ 300 K) FoS-1: Gap geometry allowed by spec 10 after intense survey:

11. GSI Helmholtzzentrum für Schwerionenforschung GmbH  Optimization of welding procedure: laser welding Low heat input Low tension Automated  Lamination stamped to final geometry  Removal of gap between yoke at 300 K Coil clamped within its elastic range Welding seams ~330 mm Cross section (yoke only) Screws ~3 m ~260 mm 11 Overview + > 130 further changes in fabrication and quality issues for series dipoles Welding seams FoS-2: Optimization toward Series Production

12. GSI Helmholtzzentrum für Schwerionenforschung GmbH Excellent quench performance Excellent mechanical stability of the coil (alternating quenches in lower and upper poles) Low quench degradation factor no de-training 12 Parametric model: q h = 4.2±0.5 J q e = 6.0±0.2 J ˑ s FoS-1,2: Quench behavior and ac losses

13. GSI Helmholtzzentrum für Schwerionenforschung GmbH FoS-2: gap height Side view of yoke: frame welded to lamination – separated – welded again (accidentially) 13 gap height: allowed by spec

14. GSI Helmholtzzentrum für Schwerionenforschung GmbH FoS: comparison FoS-2: Variation of gap height reduced by more than a factor of 2 ! Periodic structure disappeared. Yoke well within specification 14 allowed by spec gap height pole tilt FoS-2: tilt of pole surfaces reduced by more than factor of 3! Periodic structure disappeared.

15. GSI Helmholtzzentrum für Schwerionenforschung GmbH FoS-2: Magnetic field vs. geometry 15 gap heightmagnetic field deviation (relative) Full agreement between measurement of gap height (sensors) and magnetic field (rotating coil)  strong QA tools for series (both data averaged over 600 mm) FoS-2 within specification of ΔB/B < 6×10 -4

16. GSI Helmholtzzentrum für Schwerionenforschung GmbH After detailed review and analysis of FoS magnet, the optimization for the series production has been done. Geometrical and magnetic-field measurements on FoS-2 magnet showed clear improvement of the manufacturing technology. After successful tests and final check of the production drawings and processes the series production can be released soon. Conclusion 16

17. GSI Helmholtzzentrum für Schwerionenforschung GmbH 17 Egbert Fischer et al. / SC Magnets / MAC-14 Thank you very much for your attention

18. GSI Helmholtzzentrum für Schwerionenforschung GmbH 18 Egbert Fischer et al. / SC Magnets / MAC-14

19. GSI Helmholtzzentrum für Schwerionenforschung GmbH FoS: comparison 19 yoke halfes displacement FoS-2: horizontal displacement out of spec but just to be accepted

20. GSI Helmholtzzentrum für Schwerionenforschung GmbH z-900 B11.93 b2-1.05 a2-5.17 b3-8.24 a30.33 z-300 B11.93 b2-4.43 a2-2.09 b3-7.07 a30.12 z900 B11.93 b2-3.27 a2-0.38 b3-8.64 a33.07 z300 B11.93 b2-4.88 a23.23 b3-7.09 a33.31 z0 B11.93 b2-4.66 a21.42 b3-6.95 a33.04 z1500 B11.04 b226.74 a20.24 b3-100.1 a3-2.95 z1500 B11.08 b258.47 a2-8.17 b3-107.69 a35.79 Gap height (@ 300 K) Gap width with coil (@ 300 K) CS NCS R ref = 40 mm I = 13.5 kA FoS: Magnetic-Field Local allowed by spec 20 Correlation between local multipoles and magnet-gap geometry

21. GSI Helmholtzzentrum für Schwerionenforschung GmbH FoS-2 AC Loss Parametric model: q h = 4.2±0.5 J q e = 6.0±0.2 J ˑ s 21

22. GSI Helmholtzzentrum für Schwerionenforschung GmbH FoS-2 Quench behavior Excellent quench performance – 2 nd quench above nominal current Excellent mechanical stability of the coil (alternating quenches in lower and upper poles) Low quench degradation factor FoS: even better quench performance – 1 st quench above nominal current No coil degradation after yoke exchange close to SSL (90 %) measurements limited by CS and time FoS-2: 22

23. GSI Helmholtzzentrum für Schwerionenforschung GmbH SIS100 Dipole: preparation of series production... optimization of series dipoles experience with FoS1 and FoS2 guide to change of fabrication technique of yoke tight QA measures design adjustments (mechanical, thermal, electrical,...) refinement of test procedures for each craft definition of series instrumentation... !!! huge technological step forward from FoS to series dipoles !!! list of changes with > 130 entries to be implemented for series FDR: Egbert Fischer et al. / SC Magnets / MAC-14 23

24. GSI Helmholtzzentrum für Schwerionenforschung GmbH Introduction: FAIR, SIS100, dipole 24

25. GSI Helmholtzzentrum für Schwerionenforschung GmbH 25 Egbert Fischer et al. / SC Magnets / MAC-14 nominal current reached after the first quench no de-training after thermal cycling Measured with VI method q h = 4.2±0.5 J q e = 6.0±0.2 J ˑ s

26. GSI Helmholtzzentrum für Schwerionenforschung GmbH FoS-2 Critical Current Critical current-density of single superconducting wires Fit formula (L. Bottura): Highest current at quench at 16.07 kA Short sample limit: 17.8 kA Magnet already at 90 % of Short Sample Limit 26

27. GSI Helmholtzzentrum für Schwerionenforschung GmbH Backup 27 Egbert Fischer et al. / SC Magnets / MAC-14 cable parameters ► the Nuclotron cable is the core component for the fast ramped magnet

28. GSI Helmholtzzentrum für Schwerionenforschung GmbH Magnet Cooling 28 Egbert Fischer et al. / SC Magnets / MAC-14 ICEC25, 7 -11. July. 2014, Enschede Inlet – sub-cooled helium P in = 1.6 bar, T in = 4.5 K Coil out: P = 1.2 bar, two-pase (4.3 K) Joke out: P = 1.2 bar, two-phase, x = 0.9 – 1.0 Heat load: static:2 W dynamic:up to 50 W Mass flow: defined by the pressure difference P in -P out and by the total heat load hydraulic resistance of cooling channels: cable inner diameter:d = 4.7 mmiron yoke: d = 10 mm dipole:L = 54 m + 54 m P 1, T 1 <Tsl P 3, T 3 T 2 <T 1 He in He out

29. GSI Helmholtzzentrum für Schwerionenforschung GmbH provided a successfully finalized SAT and completed series FDR Site Acceptance Tests (SAT)12/2015 Final Design Review (FDR)01/2016 Release of series01/2016 First series magnet05/2016 All magnets deliveredQ4/2018 SIS100 Dipole: Series production time schedule Egbert Fischer et al. / SC Magnets / MAC-14 29

30. GSI Helmholtzzentrum für Schwerionenforschung GmbH Nuclotron type cable with insulated wires – Connect wires in series – By replacing sc. wire, operation current is adjustable.

31. GSI Helmholtzzentrum für Schwerionenforschung GmbH  Dipole magnet  Superferric magnet 1.9 T, 13 kA  Nuclotron cable, 2 phase helium cooling  Fast ramp magnet 4 T/s  Curved magnet Polyimide insulations NiCr wire Sc strands CuNi tube Iron yok e Coil

32. GSI Helmholtzzentrum für Schwerionenforschung GmbH 32 Egbert Fischer et al. / SC Magnets / MAC-14 cryostat vessel thermal radiation shield soft iron yoke bus bars suspension rods yoke cooling pipes LHe lines cable and windings 1 - Cooling tube CuNi 2 - SC wire NbTi 3 - CrNi wire 4 - Kapton tape 5 - Glasfiber tape Nuclotron cable: