Development of large aperture superconducting dipole magnet for LHC at Cryogenics Science Center

（English translation 2024-06-18）

The Cryogenics Science Center is collaborating with CERN to install a beam that will be installed in the beam final convergence section, which will be required for the LHC high-luminosity upgrade project. We are proceeding with research and development of a large-aperture superconducting dipole magnet (D1) for beam separation.
The main specifications are a coil diameter of 150mm, a rated magnetic field of 5.6T, a magnetic field length of 35Tm, and an operating load of 78% at 1.9K cooling.
We are proceeding to develop a short 2m long model magnet (Model 1) at the center that includes disassembly, reassembly and testing of the magnet. Currently, the second model magnet (Figure 1) has been completed and excitation tests are underway.
Figure 2 shows the quench test results for Model 1 and Model 2.
Initially, the quench performance of Model 1 did not meet the specifications, but by adding internal stress during disassembly and reassembly, the specifications were met.
As a result of the design of the second unit taking these results and specification changes from CERN into consideration, the second unit also met the specifications for quench performance. In the future, we plan to prototype Model No. 3 and conduct reproducibility tests, confirm magnetic field performance, etc., and finalize the final design for production.
This research and development is being carried out with the support of the ATLAS group at the Institute of Particle and Nuclear Studies, with engineering support from the Mechanical Engineering Center, and assistance with magnetic field measurements and structural analysis calculations from the Accelerator Laboratory’s Superconducting Magnet Group.