Concept of a fault tolerant linear accelerator as proposed in the SNQ project

High availability of the neutron source was the prime design goal in the 5.5 MW long pulse SNQ (Spallations-Neutron-Quelle) project a spallation neutron source designed as a neutron source for a variety of research applications, the main emphasis being on neutron scattering. On the target side a low load level was ensured by a large rotating structure, whose operating temperature would have been sufficiently low to minimise the effect of thermal cycling due to beam trips. A new concept was developed that ensured maximum fault tolerance. With the features of the equipment a very high reliability and availability of the accelerator as well as very economic operation was anticipated, because the accelerator excels by low power consumption, and no preventive maintenance on the RF system was required. (author)