1. Basic Topics for the Design of the SIS100 Quadrupole Modules MAC - 4 December 1 th - 2 nd, 2010 GSI, Darmstadt Egbert Fischer, Pierre Schnizer, Kei Sugita, Hamlet Khodzhibagiyan, Anna Mierau

2. E. Fischer et al., MAC Meeting December 1th 2010Contents 1.Main Magnets  Dipole: aperture of the CSLD  Quadrupole: high current coil design 2.Corrector Magnets  Design optimisation  Manufacture & tests 3.Quadrupole Units  Module conception  Cryostate: integration concepts 4.Conclusion

3. E. Fischer et al., MAC Meeting December 1th 2010 wider aperture ? => higher AC losses => limits for cable & coil geometrie => adjust hydraulics of the QP-Modules SIS100 Main Magnets: aperture of the CSLD MAC3 committee report: "If the harmonics can not be tolerated, a mitigation measure such as widening the magnet bore should be considered - even at the cost of higher cryogenic consumption." "The next prototype will incorporate 3 important differences with respect to the successful BNG prototype... These new features call for an urgent launch of the purchase of the new prototype..."

4. E. Fischer et al., MAC Meeting December 1th 2010  The original Nuclotron cable was adapted for the main parameters of the SIS100 dipole.  An optimisation of the sc wire characteristics was also necessary.  The AC loss estimations were proven by measurements on two-layer prototype dipoles.  A further increase of the magnet aperture requires additional reduction of the hydraulic resistance. Losses & hydraulics considerations SIS100 Main Magnets: aperture of the CSLD

5. E. Fischer et al., MAC Meeting December 1th 2010  Existing model magnets (two layer coil, 16 turns)  Nuclotron (starting design, short models )  first SIS100 full size models straight dipole, BNG (S2LD) straight dipole, JINR (S2LD) curved dipole, BINP (C2LD)  Present design status:  curved single layer design made (CSLD)  not built yet 5 AC loss as measured for the C2LD (BINP) versus the loss obtained for the S2LD magnet (BNG) SIS100 Main Magnets: aperture of the CSLD experimental verification of AC loss estimations

6. E. Fischer et al., MAC Meeting December 1th 2010 CSLD, /\ S2LD, /\ S2LD, 2c CSLD, 2c wider aperture => larger yoke => higher AC losses => hydraulic resistance must be reduced T – S diagrams for the 2c and /\ operation Helium flow trough the bus bars I, the coil II - III (inner - outher layer) and the iron yoke IV at cycles - 2c (left) and triangular (right) The straight Two Layer Dipole (S2LD) and the Curved Single Layer Dipole (CSLD) at intensive ramping modes SIS100 Main Magnets: aperture of the CSLD Losses & hydraulics: phase diagram

7. E. Fischer et al., MAC Meeting December 1th 2010 lamination geometry Cross section of the cable for the SIS100 CSLD SIS100 Main Magnets: aperture of the CSLD geometrical and hydraulic limit for horizontal aperture enlargement:for the given aperture height the loss increase must be below 40 % !

8. E. Fischer et al., MAC Meeting December 1th 2010 SIS100 Main Magnets: aperture of the CSLD example: lamella of the original CSLD vs. a design with horizontally enlarged aperture  increasing the aperture width ~ 20 %  the AC losses will increase by 50 % !

9. E. Fischer et al., MAC Meeting December 1th 2010 SIS100 Main Magnets: aperture of the CSLD Blue: TDR, Green optimised, Red: 100 mm yoke aperture example: load line, transfer function and multipoles different versions of the CSLD

10. E. Fischer et al., MAC Meeting December 1th 2010 SIS100 Main Magnets: quadrupole High current coil design for the Quadrupoles: Using the same cable as for the DP → improved hydraulics, economical benefit Adjustment of the hydraulic resistance to the DP coil in reinforcement structure smaller size 2 or 3 turn per pole design

11. E. Fischer et al., MAC Meeting December 1th 2010 Requirements Cable –Nuclotron cable –Insulated strands (max.28) => must be manufactured and tested –Strands are connected in series => efficient cooling of soldered joints SIS100 Corrector Magnets: design optimisation *

12. E. Fischer et al., MAC Meeting December 1th 2010 SIS100 Corrector Magnets: design optimisation Superconducting correctors Position of correctors All correctors are next to quadrupole. Current leads and power converter All local copper leads. Multipole cor. & steering: Their own P.C. Chromaticity: 8 magnet in series. Superconductor Low loss, 4.3µm filament diameter Cable Nuclotron type cable with insulated sc wires

13. E. Fischer et al., MAC Meeting December 1th 2010 Design: Super-ferric magnet Nuclotron type cable with insulated sc wires: –Low current (reduce lead loss) –Each wire is connected in series SIS100 Corrector Magnets: design optimisation Chromaticity sextupole

14. E. Fischer et al., MAC Meeting December 1th 2010 Multipole correctors SIS100 Corrector Magnets: design optimisation Design: Cos theta magnet –Quadrupole, sextupole and octupole nested Nuclotron type cable with insulated sc wires: –Low current (reduce lead loss) –Each wire is connected in series

15. E. Fischer et al., MAC Meeting December 1th 2010 Design: Cos theta design –Horizontal and vertical dipole nested Nuclotron type cable with insulated sc wires –Low current (reduce lead loss) –Each wire is connected in series Steering magnet SIS100 Corrector Magnets: design optimisation

16. E. Fischer et al., MAC Meeting December 1th 2010 Parameters SIS100 Corrector Magnets: design optimisation

17. E. Fischer et al., MAC Meeting December 1th 2010 SIS100 Corrector Magnets: manufacture & tests Urgent topics of preliminary work for prototyping the SIS100 quadrupole modules minimum time scale

18. E. Fischer et al., MAC Meeting December 1th 2010 108 +2 modules SIS100 Quadrupole Units: module conception courtesy of A. Kovalenko

19. E. Fischer et al., MAC Meeting December 1th 2010  The problem: How to combine the quadrupoles with the corrector elements hydraulically in an optimal scheme for stable operation, minimizing also the effort of cryostate layout, electrical connections, alignment, testing and maintenance.  Two principal different proposals are under discussion:  From cryostate design point of view the units should be as long as possible, however for testing and maintenance free access to all elements is important and may be crucial for testing, commissioning and efficient operation of the accelerator.  Discussion status @ GSI: Both version have their pro and cons - the single QP cryostate version is more expensive, whereas the combined option is more risky if a significant amount of He leckages within the cooling circuits and the connection points is considered.  A study for technological risk analysis is ordered from industry. SIS100 Quadrupole Units: module conception Two or one quadrupole in the cryostate modules?

20. E. Fischer et al., MAC Meeting December 1th 2010 Connection: warm-warm, warm-cold, cold-cold Special cryostat for injection, extraction and transfer to SIS300 Different configurations in the Arc Chrom. Sext. + QD + Col + Steering + QF + BPM Steering + QD + Col + Chrom. Sext. + QF + BPM (For multipole corrector) SIS100 Quadrupole Units: integration concept A courtesy of J. P. Meier cryostat with two quadrupoles

21. E. Fischer et al., MAC Meeting December 1th 2010 QD BPM ST QD BPM ST QD COL Schematic view of the cryostat concept with two quadrupoles Warm-warm connection Cold-warm connection Cold-cold connection QD BPM ST QD COL CS SIS100 Quadrupole Units: integration concept A courtesy of J. P. Meier

22. E. Fischer et al., MAC Meeting December 1th 2010 [1] “Conceptual analysis and a proposal to optimize the cryogenic system of the SIS100 ring and 100 Tm beam lines”, H. Khodzhibagiyan, and E. Fischer, Report on R&D contract Nr.5-1 between GSI Darmstadt and JINR Dubna, November 2004. [2] "New Design for the SIS100/300 Magnet Cooling", H. Khodzhibagiyan, E. Fischer, and A. Kovalenko, IEEE Trans. Appl. Supercond. vol. 16, pp. 411-414, 2006 SIS100 Quadrupole Units: integration concept B The original module conception [1,2]

23. E. Fischer et al., MAC Meeting December 1th 2010  Four types of modules:  M1: 1 quadrupole, 1BPM and 1steerer (9 such modules are in one segment)  M2: 1 quadrupole, 1BPM and 1multipole (10 modules)  M3: 1 quadrupole, 1multipole and 1collimator (5 modules)  M4: 1 quadrupole, 1steerer and 1collimator (6 modules)  The heat generated in the multipoles, BPMs, collimators and steerers was estimated based on the experimental data for similar elements of the Nuclotron. (static heat leak: 3 W for dipole and 2 W for quadrupole) [1, 2] : The heat releases for the different super cycles for the SIS100 dipole magnet and the four types of modules. SIS100 Quadrupole Units: integration concept B cryostat with one quadrupole

24. E. Fischer et al., MAC Meeting December 1th 2010 [1, 2] : Some results of the hydraulic calculations SIS100 Quadrupole Units: integration concept B cryostat with one quadrupole

25. E. Fischer et al., MAC Meeting December 1th 2010 The module proposal for the actual lattice (2010) SIS100 modules with one quadrupole Type of Module Number per segment Module structure M14QD - BPM M23Steerer - QF M31Steerer – QF - Multipole M44Ch. Sextupole – QD - collimator M56Steerer - QF - BPM M64Steerer – QD - collimator M74Ch. Sextupole – QF - BPM M81QD - collimator M91Multipole – QD - collimator ► most intense for ∆P in QP units (including two quadrupoles):  Sextupole + QD + Collimator + Steerer + QF + BPM or  QP units including Multipole. ► probably: For the most critical QP unit the hydraulic resistance will be higher than for the dipole due to the 4 mm He-channel in the multipole, the steerer and the sextupole ◄ most intense for ∆P, (i.e. M3 defines the necessary hydraulic resistance of all the other modules) SIS100 Quadrupole Units: integration concept B

26. E. Fischer et al., MAC Meeting December 1th 2010  Magnetic system of the Nuclotron consists of modules.  Each module contains a support structure, a cryostat and support with the device for adjustment.  There is access from both ends of the module to all electrical connections and to about 70 welded and brazed joints of the helium channel of the module.  Each module is tested on cold the test facility: training of the magnet; measuring the quality of the magnetic field in the aperture; the measurement of the hydraulic resistance and the AC losses at pulse operation mode; testing the leak tightness of the helium channels.  These design principles of the Nuclotron magnetic system had allowed to find easily and remove helium leaks occurring during operation directly in the accelerator tunnel, without removing of the module. The Nuclotron system: SIS100 Quadrupole Units: integration concept B

27. E. Fischer et al., MAC Meeting December 1th 2010 Disadvantages of the QP-units (including two quadrupoles): §1 No access to half of the joints of helium channels, located between the QPs; §2 The test bench must have 2 pairs of current leads for the training of each QP separately; §3 We'll have to have two parallel cooling channels for each of the QPs, because of the large hydraulic resistance in their series connection. Otherwise it would be difficult to measure the hydraulic resistance of each QP separately. §4 One must enter a restriction on the cooling rate for the elements due to the different thermal contraction of every single QP and devices for their consolidation. This will increase the time and cost of tests at the facility. §5 Magnetic measurements of the QPs at room and helium temperatures will be less accurate than each QP separately....  The disadvantages include high risk for project management, time and cost schedule. SIS100 Quadrupole Units: integration concept B

28. E. Fischer et al., MAC Meeting December 1th 2010 Conclusion Three full size SIS100 dipole models based on a two layer coil design were intensively tested. The results fit well to the theoretical estimations. The present design status of SIS100 dipole is thoroughly analysed and ready for manufacturing of the first curved single layer dipole. If the harmonics of the actual design can not be tolerated by beam dynamic considerations, the magnet bore could be widened by about 20 %. Design optimisation, manufacturing and test of the quadrupole and corrector magnets is an urgent task for proceeding to the final SIS100 layout. The final design of the quadrupole units must be based on the to yet to measured operation parameters next to the already started risk analysis.