Performance of the First LHC Main Quadrupoles Made in Industry

After the creation of a new dedicated factory and a period of technology transfer, ACCEL Instruments has constructed and delivered the first LHC main quadrupole magnets to CERN. The design of these magnets had been the subject of a close collaboration between CEA-Saclay and CERN. Thus, CEA ensures also the technology follow-up for the fabrication of 400 quadrupole magnets and their cold masses. The two quadrupoles delivered to CERN were bare magnets, i.e. magnets not integrated into their cold masses. The purpose was to verify their performance before fabricating full cold masses. The two magnets were tested at 1.9 K in a vertical cryostat at CERN. For both magnets the current could be ramped up to well above their nominal level before a quench occurred. The second powering provoked on one of the magnets a quench at the ultimate level of excitation and in the other magnet no quench, even after the ultimate current value had been well exceeded. The field quality measurements, as far as possible in the vertical cryostat, confirmed the multipole content already found during the warm field measurements made in the factory.