Superconducting detector magnets for high energy physics

Various superconducting detector solenoids for particlephysics have been developed in the world. The key technology is thealuminum-stabilized superconductor for almost all the detectormagnets in particle physics experiments. The coil fabricationtechnology is also important and it has advanced along with theconductor technology, such as the inner coil winding technique,indirect cooling, transparent vacuum vessel, quench protectionscheme using pure aluminum strips and so on. The detector solenoidsdesign study is in progress for future big projects in Japan andEurope, that is, ILC (International Linear Collider), FCC (FutureCircular Collider) and CLIC (Compact LInear Collider), based on thetechnologies established over many years. The combination of goodmechanical properties and keeping a high RRR is a key point for thedevelopment of Al-stabilized conductor. The present concern for thedetector solenoid development is to have been nearly losing the keytechnologies and experiences. Nowadays, there are no industrialcompanies having the capacity to manufacture such aluminumstabilized superconductor. Complementary efforts are seriouslyrequired to re-realize and validate the performance required in thefuture projects in collaboration with worldwide institutes andindustries. Some mid-scale physics experiments required detectorsolenoids wound with not aluminum stabilized conductor butconventional copper stabilized conductor. The specific requirementis to control the magnetic field distribution precisely, and theefforts to realize the requirement are on going with regard to themagnetic field design technology with high precision simulation,coil fabrication technology and so on.