Les sentiments négatifs à travers les siècles (l'évolution des champs sémantiques de la colère, de la peur et de la douleur en français dans la base textuelle FRANTEXT (1500-2000))

PARIS7-Bibliothèque centrale (751132105) / SudocSudocFranceF

Accelerated Lifetime Test of Spoke Cavity Cold Tuning Systems for Myrrha

International audienceWithin the framework of MINERVA, the first Phase of MYRRHA (Multi-purpose hYbrid Research Reactor for High-tech Applications) project, IN2P3 labs are in charge of the developments of several accelerator elements. Among those, a fully equipped Spoke cryomodule prototype was constructed, it integrates two superconducting single spoke cavities operating at 2K, the RF power couplers and the associated cold tuning systems. The extreme reliability specified for this project motivated to conduct ALT (Accelerated Lifetime Test) on two extra cold tuning systems in cryomodule like environment. Thus, by gathering information from experimental data, many aspects can be enhanced like maintenance plan consolidation, determination of aging indicators and design optimization of the whole system and its sub components. This paper describes the complete ALT process from the studying elements and the test environment design, to the experimental results and findings

ESS Spoke Cryomodule and Test Valve Box

International audienceESS project aims being the world’s most powerful neutron source feeding multidisplinary researches. The superconducting part of the ESS linear accelerator includes 28 b=0.5 352.2 MHz SRF niobium double Spoke cavities. Paired in 13 cryomodules and held at 2K in a saturated helium bath those cavities will generate of an accelerating field of 9MV/m. The prototype Spoke cryomodule holds two cavities and their RF power couplers and integrates all the interfaces necessary to be operational within the linac machine. It is now being fabricated and its assembly will be performed with dedicated tooling and procedures in and out of the clean room. This prototype will be tested by the end of 2015 at IPNO site and then at full power at FREIA (Uppsala university) test stand. A valve box has thus been designed to take into account the specific features of this prototype cryomodule and of the cryogenic environments of both test sites. This valve box is also considered as a prototype of the cryogenic distribution of the linac Spoke section. This element will then be used for the tests of the series cryomodules. We propose to present this prototype Spoke cryomodule for ESS and the test valve box