2017 Volume 52 Issue 3 Pages 149-156
The large-aperture beam separation dipole (D1 magnet) needs to be developed for the high luminosity upgrade of the Large Hadron Collider (HL-LHC) at CERN. This magnet requires a field integral of 35 T·m at 12.0 kA and 1.9 K with a coil aperture of 150 mm. The technical challenges are controlling the pre-stress of the thin coils, achieving high radiation resistance and managing the iron saturation. In the framework of CERN-KEK collaboration, KEK is in charge of developing the D1 magnet and has been conducting design studies since 2011. A design including a single-layer coil based on Nb-Ti technology with a collared yoke structure was selected and fabrication of the first 2-m model started in 2015. In this paper, the overview and design studies of the D1 magnet are first introduced. Then, fabrication and test results of the first 2-m model are reported. Finally, future perspectives for the D1 production magnets are described.
