Design of the spoke cavities and its associated cryomodule for the MYRRHA superconducting LINAC

International audienceThe MYRRHA Project aims at the construction of an accelerator-driven system (ADS) at MOL(Belgium) for irradiations and transmutations experiments purposes. The facility will feature asuperconducting LINAC able to produce a proton flux of 2,4 MW (600 MeV – 4 mA). The first sectionof the superconducting linac will be composed of 352 MHz (beta = 0.37) spoke type superconductingcavities housed in short two cavities cryomodules operating at 2K.A first R&D phase on the Spoke cavities design and performances has been initiated in 2015. Thefirst results on the performances of two prototypes designed for the MHYRRA LINAC, tested at 2Kare presented.The cryomodule has for main design constrains the availability and the reliability required by theoperation in a nuclear plant environment. To fulfil these requirements several solutions have beentaken into account and especially the so-called “Fault-tolerance” scheme that will be used tooperate the proton beam. The second part of the paper describes the whole cryomodule design(spoke cavities, Cryostat, Power Coupler, Cold Tuning System…) by mainly focusing on theconceptual choices driven by the reliability and fault tolerance scheme requirements