The next generation neutrino mass experiment KATRIN (Karlsruhe Tritium Neutrino experiment) uses a series of superconducting magnet systems, which guide the electrons from tritium beta-decay adiabatically from the source to the detector within a magnetic flux of 0.0191 . The electron transport and tritiuAm pumping sections contain two complex magnet systems; the Differential Pumping Section (DPS2-F) and the Cryogenic Pumping Section (CPS) that are designed with a central magnetic flux density from 5 T to 5.7 T for persistent-mode operation. Each system has a series of superconducting solenoids in a zigzag arrangement that is designed to enhance the tritium pumping efficiency. The 7 m long DPS2-F was commissioned at the end of 2010 and the magnetic performance of the DPS2-F was accepted for the KATRIN experiment. The DPS2-F was operated for more than 325 hours in persistent-mode to investigate long term field stability, which is required to stay within 0.01% at the nominal field for a 60-day measurement run. All seven modules of the CPS were manufactured and successfully cold-tested.
In order to build a compact linear accelerator, high acceleration gradients of superconducting radio frequency (SRF) cavities have to be achieved. In many large accelerators, e.g. XFEL, CEBAF or SNS, operational limitations are caused either by a limit on available overall cooling power of refrigerators or on cooling capabilities of sc cavities. So, for the further improving of sc cavity cooling, it is possible to increase either a quality factor (Q
0) or to improve a heat transfer at the cavity surfaces. 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. In the present paper, application of sub-cooled superfluid (sf) helium for linac-based Free Electron Lasers, Energy Recovery and Proton Linacs is considered. In order to limit the present discussion, its application to CEBAF/SNS-style cryomodules is discussed in detail. For operation at higher RF power levels, further cooling improvements of a fundamental power coupler are needed and design modifications also presented.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.