Status Of Lhc Low-Beta Quadrupole Magnets, Mqxa, At Kek

KEK has developed a superconducting quadrupole magnet, MQXA, for the LHC interaction region. This magnet is required to generate an operating field gradient of 215 T/m in the magnet bore of 70 mm and have an effective magnetic length of 6.37 m. For the accelerator operation, sixteen MQXA magnets will be installed in total for four interaction regions, and the cold tests of ten MQXA magnets of them have been completed. These ten magnets had good quench performance and satisfactory field quality for the requirement of beam optics. This paper describes the production quality and the magnet performance of the MQXA magnets.