Innovative approach toward new generation sources

The world neutron community needs more neutrons and more opportunities at a much less expense. A worldwide neutron net work proposed here would be a future dream of the community. A neutron source being able to satisfy such requirements is the innovative neutron source. A new FFAG synchrotron will be the best candidate to realize such a network consisting of various spallation sources ranging from kW to MW in beam power. There would be many advantages with this accelerator. The next are the target issues: how to accept a higher beam-power beyond 5 MW. Some thoughts are discussed here. Various moderators are discussed in connection with the requirements from the instruments proposed for JSNS, mainly focussed on the performance and utilization of a coupled hydrogen moderator with optimized premoderator, aiming at more efficient use of neutrons. A new idea for pulse shaping, 'mechanical poisoning' is proposed. At an existing spallation source the number of instruments is much smaller than at a reactor. In order to install as many instruments as possible, the beam extraction and branching methods become very important. However, even at a reactor, where mainly monochromatic neutrons are used, the neutron-intensity losses due to beam multiplexing uses are significant. This problem becomes more serious in case of a pulsed source, where in many cases polychromatic beams are required. This issue is also discussed. (author)