CERN-INFN, 23 Febbraio 2017 Stato del programma 16 T Davide Tommasini

Questions addressed by the program Are 16T accelerator magnets feasible? can we achieve the field with “sufficient” margin? can we protect the magnet, once in the whole circuit? can we meet the field quality requirements? If yes, at which cost? cost of conductor cost of construction

Masterplan 2017-2023 Conductor Procurement of ~ 1 t of conductor/year to feed models and demonstrators Increase of Jc up to FCC target (1500 A/mm2 @ 4.2 K, 16 T) Vigurous conductor R&D, the FCC program is co-funding a 2nd line at Bruker-EAS Initiatives in Russia (Bochvar/TVEL), Korea (KISWire/KAIST), Japan (KEK/Jastec/Furukawa) for conductor development towards target Jc Comprehensive electro-mechanical characterization Feed the FCC Conceptual Design Report (end 2018) One reference option, including cost, plus a description of the alternative options. Models (2016-2020) Design, Manufacture & Test of ERMC and RMM Models. Demonstrators (2018-2023) Design, Manufacture & Test of Demonstrator Magnets (< 2m long). Longer magnets (2023-)

Base (interna, confidenziale) per ordini conduttori Table I : number of coils to manufacture as a function of coil type and time   Description Mass [kg] Site 2017 2018 2019 2020 2021 2022 2023 ERMC non-graded 70 CERN 3 CEA CIEMAT 1 2 RMM non-graded ERMC graded-HF 15 5 ERMC graded-LF 27 RMM graded-HF 10 RMM graded-LF DemCea - HF 30 DemCea - LF 42 DemCiemat - HF DemCiemat - LF DemInfn - HF INFN DemInfn - LF DemCern - HF 7 DemCern - LF ProtCern – HF (6m) 120 ProtCern – LF (6m) 170

Present programs FCC 16 T Magnets Technologies EuroCirCol WP5 US Magnet Development Program

Recent initiatives CEA (being finalized) Development and manufacture of a demonstrator model. CERN will provide the conductor, the main components and a monetary contribution. CIEMAT (looking for funding the laboratory infrastructure) Participation to the manufacture of ERMC/RMM model coils and possibly to the development and manufacture of a 16 T demonstrator (probably common coil). INFN (under discussion) Development and manufacture of a demonstrator model. CERN will provide the conductor, the main components and a monetary contribution. Swiss contribution & PSI (signed) Exploration of a canted cosine-theta options (whole magnet or instert) Development of reaction resistant Nb3Sn splices

Models: 16 T Magnets Technology Program Two model types: ERMC and RMM, non-graded and graded versions 530 800 a real straight section a structure for fields up to 18-19 T, key & bladders for ease of multiple assembly ERMC coils compatible with use in the RMM RMM equipped with harmonic field probes RMC ERMC/RMM demonstrate that the field level can be achieved with margin and limited/no training measure and characterize field quality static and dynamic with different conductors management of transitions (layer jump, ends …) study/optimize coil manufacture (including interface conditions coil/pole, coil-coil …) explore different loading configurations/strategies (transversal & longitudinal) splice studies in real magnet configuration

*H2020-INFRADEV-1-2014-1 EuroCirCol WP5* Explore design options for a 16 T accelerator dipole magnet Feed the FCC-CDR with a baseline magnet, including cost Japan KEK Finland TUT France CEA Italy INFN Netherlands UT Spain CIEMAT CERN&UNIGE WP 5 TASKS of WP5 5.1: Work Package Coordination  5.2: Study magnet design options  5.3: Develop dipole magnet cost model  5.4: Develop Magnet Conceptual Design  5.5: Conductor studies  5.6: Devise quench protection concept  5.7: Produce Magnet Engineering Design   Three options are being considered: Block coils (CEA) Common coils (CIEMAT) Cosinetheta (INFN) *H2020-INFRADEV-1-2014-1

US MDP Priority is to demonstrate 14 T in a cosinetheta configuration using part of the tooling of the 11 T. Tests planned in 2018.

Salient common assumptions Magnet length 14.3 m Free physical aperture 50 mm Field amplitude 16 T Margin on the load-line @ 1.9K 14 % Total time delay 40 ms Critical current density @ 1.9 K, 16T (total) 2300 A/mm2 Conductor fit (Jc/B) Bernardo’s fit Degradation due to cabling 3% Minimum Cu/nonCu 0.8 also check 0.9-1.0 Maximum strand diameter 1.2 mm also check 1.1 mm Maximum (any) stress on conductor 200 MPa Maximum hot spot temperature (@ 105% Inom) 350 K Maximum number of strands in a cable 40 check up to 60 Maximum voltage to ground (magnet contribution) 1.2 kV set as tentative value Maximum TOTAL voltage to ground 2.5 kV Conductor cost (performance based) 5 Euro/kAm

Summary of present status and next steps Conductor: about 50 km RRP from OST in house agreements with Russia, Korea, Japan for conductor development towards target Jc ERMC/RMM: design completed start winding in April 2017 EuroCirCol: three design options available in 2D (electromagnetic and mechanical) further work and initial 3D until FCC week in Berlin (May 2017) quench studies well advanced, a common tool for all teams cost model: well advanced, still major uncertainty on conductor cost selection of one baseline design for the FCC CDR, description of the alternative options Demonstrators: ideally constructional design of all design options as basis for demonstrators start winding in 2019 ideally one demonstrator per each of the EuroCirCol design options, possibly one more (canted type) depending on advancement of work at PSI and US MDP one 14 T demonstrator being developed with the US MDP

Grazie