Study and test of a superconducting accelerating module for the Spiral2 project

The SPIRAL2 project, in its construction phase at GANIL in Caen, will increase the capabilities of the current existing facility SPIRAL. This upgrade consists in the construction of a production area of rare radioactive isotopes associated to a superconducting linac. The latter can accelerate a 5 mA deuteron beam up to 40 MeV and can handle a wide variety of ions (protons, deuterons, ions with a charge over mass ratio of 1/3) up to 14.5 MeV/u at 1 mA. The targeted fission rate (∼10¹⁴ fissions/seconds) and accelerating polyvalence is achieved thanks to the superconducting technology. The study, the conception and integration of the superconducting accelerating modules are in charge of the Nuclear Physics Institute of Orsay (IPNO). The PhD work presented here consisted in first testing and characterising mechanically and electromagnetically the superconducting quarter-wave resonator in a qualifying cryostat (- 269 deg. C). Then, a fully-equipped accelerating module has been tested without beam. More specific studies have been carried out on the Q-disease, on microphonics and on the frequency tuning system with moving plunger, a novel system for superconducting cavities. The validation of the accelerating module performances during the PhD period has lead to the fabrication phase launching of the accelerating cavities and their modules. (author)