1. Task7: NUSTAR2 - Design and Prototype Construction of a Radiation-Resistant Magnet C. Mühle GSI Task leader: G. Moritz /GSI

2. High-radiation area Design parameters and layout of the Super-FRS Magnets in the high radiation area QuantityField/gradient Length Usable apert. Gap height/Pole radius Dipole 1 11° 30.15-1.6T 2.39m 380x140mm 170mm Quadrupole 1 Ap.rad.10cm 21.5-15T/m 1m Ø90mm 100mm Quadrupole 2 Ap.rad.20cm 10.8-7.6T/m 1m 380x200mm 200mm Sextupole 121.5-14T/m 2 0.6m 380x200mm 200mm

3. Recap of first year Original idea: Use of superconducting radiation resistant dipoles Investigation of radiation loads: Heat load on the cryogenic system for a 5 ton magnet: ≈ 2.3 kW (expected FAIR cryogenic power: 20 kW) => economic operation not possible Decision Normal conducting magnets with mineral insulated cable (MIC) Surveying and alignment system for high-radiation areas Not directly influenced by this decision => Main work in 2006 was dedicated to the conceptual design of a dipole with MIC

4. Conceptual design of a dipole with MIC: Cooling Cooling options: direct: hollow conductor indirect: solid conductor + radiator Direct cooling: Advantage: good heat transfer Disadvantage: radiolysis Indirect cooling: Advantages: pressure drop and cooling power can be designed independently from coil no radiolysis water and power connectors separated Disadvantage: limited heat transfer Decision: indirect cooling

5. Conceptual design of a dipole with MIC: Coil Conductor: Cable Size 19mm x 19mm Sheath Thickness 1 mm Insulation Thickness 1 - 1.5 mm Cond. Area 190 mm 2 Unit Length 100m Radiator: Copper plate 12 mm thick Stainless steel tube 10x1mm Coil system: 2 x 192 turns, 12 columns, 2 x 16 layers 2 x 8 double pancakes ≈ 100 m conductor per single pancake total conductor length ≈ 3.2 km

6. Conceptual design of a dipole with MIC: Yoke Requirements: α=11°, r=12.5m, B max =0.15-1.6T L=2.39m Useful aperture 380x140mm (ΔB/B≤±2x10 -4 ) Gap height 170mm Yoke design H-type Curved Laminated thickness 2 bis 4 cm cut by laser final milling of pole profile Cross section 2740mm x 2020 mm Yoke weight 85 t Pole shims but no active correction Longitudinal split into 3 parts

7. Conceptual design of a dipole with MIC: Dipole operation I=610A P=122kW Cooling ΔT=21.9K 79.2 l/min @ 1bar Conductor temperature: Return water temperature +40K

8. Construction of a prototype dipole with MIC To be done in the remaining project time: Manufacturing design Production of tooling and first (test) double pancake Production of full coil Production of yoke Assembly of final magnet Time scale ≈ 1 year => close to the limit, but still feasible Cost estimation of prototype magnet incl. tooling: 1.5 M € Budget This task: 568 k € (50%EU,50%GSI) Budget gap: ≈ 950 k € Redirect money from other tasks Finance remaining gap by GSI

9. Surveying and alignment system for high-radiation areas  Measurement concept and simulation of alignment approach nearly finished  Photogrammetric solution on Super-FRS target area working platform with four cameras on two movable vehicles  Sequential photogrammetric survey of inaccessible areas during shutdown

10. Surveying and alignment system for high-radiation areas Problems to solve:  mounting and fiducialization of excentric magnet points  Penetration of shielding between magnets and working platform  Remote-controlled adjustment of magnet positions (radiation! weight!)