Design of injectors and stay-alone cryostats with superconducting cavities for high RF powers applications

Abstract

Injectors and stay-alone cryostats with superconducting (sc) cavities are sometimes applied at modern particle accelerators. Typically, very stringent requirements on beam quality are foreseen at injectors, and application of sc cavities is advantageous, particularly if operation at high current densities and high accelerating gradients is foreseen. Stay-alone cryostats with one or few sc cavities also find applications, e.g. at ELBE, DIAMOND, S-DALINAC accelerators, and accelerate particle beams in High Frequency fields. In the future, very high RF fields will be needed, and improvement of the cooling of cavity surfaces will improve cavity performance. Application of a sub-cooled superfluid helium gives several advantages, e.g. higher heat flux densities, longer time for onset of a film boiling regime and shorter recovery time, reduced Kapitza resistances, etc [2]. In the present paper, an application of sub-cooled superfluid helium for injector and stay alone cryostats is considered. Design of the cryogenic system is presented in some details and possibility of adapting of such injector for future applications is also discussed.