Important superconducting devices in particle accelerators are superconducting magnets and superconducting cavities. The former is a DC superconducting application and the latter is a radio-frequency application, each of which requires quite different materials and technologies. The basic differences will be given in this section.
The development of superconducting cavities has a history of five decades in Japan. In this period, many world-leading achievements were released, including the world’s first full-scale application, ampere-class beam current accumulation, and the development of high-power input couplers and higher-order-mode dampers. These achievements were based on Japanese technology supported by cooperation with companies.
In the 1960s, basic technologies have been established for the practical use of superconducting magnets. The superconducting magnet technologies are widely used in large accelerator applications. This paper describes the principle and history of the superconducting magnets for synchrotrons, and also describes the magnetic field design of the superconducting magnet and quench protection including actual examples.
The refrigerator technology is indispensable for superconducting accelerators. The primary function of the refrigerator is to keep the low temperature environment for the superconducting devices such as superconducting RF (SRF) cavities and superconducting (SC) magnets, and to remove generated heat from these superconducting devices and heat leakage from the room temperature ambience. SRF cavities and SC magnets have different thermodynamic characteristics from cryogenic point of view, and hence the refrigerators for each of them have different configuration to establish appropriate cooling schemes. This article describes the refrigerator technology for SRF cavities and SC magnets with emphasis on the different cooling schemes for each device.
The reason of superconducting accelerators being adopted in many projects of the world is the success of the superconducting cavities at TRISTAN and the successful results of the development of niobium materials. This paper describes the history of niobium for superconducting cavities and current market of high purity niobium.
Practical superconducting wires and tapes have been developed after a discovery of superconductivity in 1911. Nowadays, many “practical” superconducting wires and tapes are available commercially and used for various applications. Most of them are multifilamentary wires with stabilizer. The present status of practical superconducting wires and tapes are introduced with short histories.
Superconducting detector solenoid magnets for particle physics have advanced with Al stabilized superconductor and indirect-cooling technology, in particular, for large-scale particle detector systems in colliding accelerators, since 1970s. This paper will introduce the key technologies to realize “thin and transparent” solenoidal magnetic field for momentum analysis of particles passing through the superconducting coil with minimum interaction, and briefly discuss the future prospect.
A muon beam generated with accelerator is utilized for elementary particle physics, material science and for wide application. For higher intensity of a muon beam superconducting magnets are being adopted in muon source recently. High radiation tolerance is required on the superconducting magnets in high radiation environment near a production target. Development of the superconducting magnets for muon source is introduced in this manuscript.
The history of superconducting cyclotrons is reviewed. The first successful superconducting cyclotron was designed and constructed by Henry Blossor’s group from MSU, using circular superconducting coils. Later, the technology of superconducting coils was developed, and a separate sector ring cyclotron using non-circular coils was completed in RIKEN RI beam factory in 2006. In the above two cyclotrons, only the magnet was superconducting. But Tritron project in Germany aimed at making a completely superconducting cyclotron where acceleration cavities were also superconducting. Unfortunately, it has not yet been put to practical use. Superconducting cavity technology has been developed at present, and a fully superconducting cyclotron is not a dream.
The synchrotron radiation accelerator facility, so called light source accelerator, becomes widespread all over the world. Especially, the 3rd generation light source is applied to almost of the institute as a most useful machine for material structure science. As it spreads, the machine components is standardized to be able to respond to requirements of light performance from various beam line users. For this standardization, this report overviews how the superconducting technology has been treated as accelerator technology and future perspective of superconducting application in light source accelerator.