• J.-L. Biarrotte
  IPN, Orsay
• H. Klein
  IAP, Frankfurt am Main
• A.C. Mueller
  IN2P3, Paris
• P. Pierini
  INFN/LASA, Segrate (MI)
• D. Vandeplassche
  SCK-CEN, Mol

The goal of the MYRRHA project is to demonstrate the technical feasibility of transmutation in an Accelerator Driven System (ADS) by building a new flexible irradiation complex in Mol (Belgium). The MYRRHA facility requires a 600 MeV accelerator delivering a maximum proton flux of 4 mA CW operation. Such a machine belongs to the category of the high-power proton accelerators, with an additional requirement for exceptional reliability: because of the induced thermal stress to the subcritical core, the number of unwanted beam interruptions should be minimized down to the level of about 10 per 3-month operation cycle, a specification that is far above usual proton accelerators performance. This paper describes the reference solution adopted for such a machine, based on a so-called 'fault-tolerant' linear superconducting accelerator, and presents the status of the associated R&D.