The COVID-19 restrictions have impacted the schedules of the LS2 and of the HL-LHC activities. Concerning the LS2 schedule, the hardware commissioning of LHC should be completed by March 2021 for all sectors except the S67.
WP17 Infrastructure, Logistics and Civil Engineering
Uppsala University in Sweden has been a valuable collaborator since the foundation of CERN. In the 1950’s, Uppsala, having just constructed its own cyclotron, contributed to the development of the very first accelerator at CERN: the synchrocyclotron.
Since Issue3, three of the six series magnets were tested at cold [S1, S2, and S3], and another one [S4] is ready for testing on a test bench in SM18. On the production side, the construction of the cold mass assembly of the first spare magnet has started
The LHC sectors are cooled by eight similar helium refrigerators. P4 needs more cooling capacity due to the superconducting RF. This has not limited LHC so far but would be a bottleneck for the HL-LHC era.
Today’s LHC environment is subject to different radiation types, particle types and energy ranges. In particular, at the machine-experiment regions the main sources of radiation come from beam collisions at experiments and beam interactions.
During the last year, several advancements have been made in the Warm Powering; among them some important steps towards implementing expanded modularity and guaranteeing unprecedented precision.
An important milestone was achieved in June 2020 with the successful test at CERN of a demonstrator of the cold powering system for the HL-LHC magnets. Demo 2 incorporates a superconducting 60-m long power transmission line, the Superconducting Link.
Two prototypes of RF dipole cavities which provide horizontal crabbing for the HL-LHC were successfully built at CERN. The frequency tuning setup before the final two welds is shown in the figure below.
The most significant advancement has been the test of the third US-AUP full size magnet (MQXFA03). It reached nominal gradient with limited training and is the first magnet ready to be included in the first cold mass to be installed in the IT-String test.
