All Q2 cryo-assemblies required for the tunnel validated
All eight HiLumi Q2 cryo-assemblies required for installation in the LHC tunnel, containing the longest accelerator-quality Nb₃Sn magnets ever built, have been validated.
By Susana Izquierdo Bermúdez (CERN)
On Tuesday 1st September, the cold powering test of the eighth and final Q2 cryo-assembly required for HiLumi LHC installation – containing the MQXFB11 (CERN-made quadrupole) and MCBXFB09 (CIEMAT-made corrector) magnets – was completed, including the final 100 K high-voltage test.
This represents a major milestone for Work Package 3 (responsible for the interaction region magnets) and for the wider superconducting magnet community; produced at CERN, the MQXFB magnets are the longest accelerator-quality Nb₃Sn magnets ever built, with a nominal peak field of 11.3 T and a magnetic length of 7.2 m.
Like the rest of the series, MQXFB11 reached the target current of 16.53 kA at 1.9 K and 4.5 K, demonstrating a large temperature margin, excellent memory after a thermal cycle, and the ability to reach nominal current at ramp rates of up to 100 A/s (see training history in figure 2).
On Tuesday 1st September, the cold powering test of the eighth and final Q2 cryo-assembly required for HiLumi LHC installation – containing the MQXFB11 (CERN-made quadrupole) and MCBXFB09 (CIEMAT-made corrector) magnets – was completed, including the final 100 K high-voltage test.
This represents a major milestone for Work Package 3 (responsible for the interaction region magnets) and for the wider superconducting magnet community; produced at CERN, the MQXFB magnets are the longest accelerator-quality Nb₃Sn magnets ever built, with a nominal peak field of 11.3 T and a magnetic length of 7.2 m.
Like the rest of the series, MQXFB11 reached the target current of 16.53 kA at 1.9 K and 4.5 K, demonstrating a large temperature margin, excellent memory after a thermal cycle, and the ability to reach nominal current at ramp rates of up to 100 A/s (see training history in figure 1).
The two spare MQXFB magnets are now in the final stages of fabrication and will be tested in the coming months.
Progress across the remaining magnet assemblies is also steadily approaching the finish line. All magnets required for HiLumi LHC installation that undergo vertical testing have now been qualified, and 70% of the cryo-assemblies containing new magnets have been completed.
Step by step, the new cryo-assemblies for the new HiLumi interaction regions of ATLAS and CMS are taking shape, and dismantling of the current triplets in the LHC has begun.
