1. 1 M. Modena for the CLIC MDI magnet study Team (A. Aloev, P. Thonet, E. Solodko, A. Vorozhtsov) CLIC MDI Meeting,16 January 2015

2. 2 CLIC experiments “roll-in” concept and layout developed for 3 TeV and L* = 3.5 m: 2Michele Modena M. Modena, CLIC MDI Meeting on 16 January 2015 …Remind of what was done:

3. 3 3 - A potential QD0 solution based on hybrid concept for a: high strength, compact, stabilizable, without any active cooling, was developed, and integrated in the MDI. - An antisolenoid was also developed for the same layout. M. Modena, CLIC MDI Meeting on 16 January 2015

4. 4 Gradient: highest as possible towards a nominal value of: 575 T/m Total Length: 2.73 m (…possibly to be splittable in 2 longitudinal modules…) Magnet Bore Radius: 4.125 mm Field Quality: in the order of ≤10 relative units… Tunability: -20% minimum Major geometric and others boundary conditions: Spent beam vacuum pipe presence:  the QD0 horizontal midplane must be free Stabilization: as for MBQ magnets in the linac modules, QD0 needs to be actively stabilized in the nm range  weight should be minimized as well as any vibration sources. Alignment will be critical: 10 µm total budget for fiducialization and alignment  we the quadrupole active part (poles) should be visible Anti-solenoid presence (for beam dynamic reasons AND PM blocks shielding). “Nominal” Requirements for QD0 (3TeV, L*=3.5 m): : M. Modena, CLIC MDI Meeting on 16 January 2015

5. 5 Gradient: ? Required total Length: ? ; could be split in sub-elements ? Magnet Bore Radius: ? mm Field Quality: ≤? relative units… Tunability: minimum -?% Geometric and other boundary conditions still present: Spent beam chamber presence: IDEM as for L* 3.5 m:  the QD0 horizontal midplane must be free Stabilization: IDEM: weight should be minimized as well as any vibration sources. Alignment TIGHTER?: will be probably more demanding of the 10 µm total budget asked for L*=3.5 m  we need to “see” the quadrupole active part (poles). Major differences: magnet will be not anymore inside the detector  compactness less critical (but weight will remain critical)  access (for assembly, alignment, etc) less critical  Anti-solenoid not anymore necessary? OTHERS? Requirements for longer L* ? (for a same 3 TeV layout ? Or other energy?) M. Modena, CLIC MDI Meeting on 16 January 2015

6. 6 The super-ferric variant (i.e. same hybrid core design but with small superconducting coils at the place of the low current density resistive coils) will minimize the weight (and the cross section) preserving the “visibility” and accessibility of the iron part, making easier and more precise the alignment and the stabilization the QD0. ILC parameters: Gradient 127 T/m Aperture radius 10 mm Ampere-turns 5 kA Possible QD0 design evolution, a super-ferric version: 1.Quadrupolar core in Permendur 2.SmCo PM inserts 3.Post-collision line vacuum chamber 4.Return iron yokes 5.Coil packs: 9 NbTi SC wire turns wound around the 4.5 K LHe cooling circuit pipe. 6.Cryostat @75K shield 7.Cryostat assembly M. Modena, CLIC MDI Meeting on 16 January 2015

7. 7 The main requirements & boundary conditions for SD0 magnet are (as for QD0): 1)Strongest as possible gradient 2)Tunability of min. -20 % 3)Minimized weight and vibrations (magnet must be actively stabilized) 4)Integration with the Post Collision vacuum pipe. ParameterValue Inner radius4.3 mm Nom. Sext. Gradient 219403 T/m2 Magn. Length0.248 m SD0 hybrid design and procurement status: M. Modena, CLIC MDI Meeting on 16 January 2015

8. 8 Tendering for the central components closed on the 6 January: Offers under evaluation. Compactness is less critical respect to QD0 (magnet is placed in the Accelerator Tunnel just at the border with the Experimental Hall). The prototype manufacturing should permit to investigate the precise assembly of several (4) longitudinal sections, each one equipped with PM blocks (same concept of QD0). Key aspects: -Manufacturing (precision) of each Permendur sector, PM block, etc. -Sorting of PM blocks -Assembly of the sectors (magnetic forces between blocks, fragility of PM blocks,…) -Fiducialisation and alignment M. Modena, CLIC MDI Meeting on 16 January 2015

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