The European spallation source

The Study Panel of the CEC on Neutron Beam Sources (Large Installations Plan), which addressed the short and long term prospects for neutron scattering research within the EC, recommended initiating study groups to investigate options for a new research reactor and a new spallation source to ensure Europe's continued pre-eminence in neutron scattering beyond the year 2000. Together with KFA Julich, Rutherford Appleton Laboratory has recently taken the initiative to explore possible accelerator-based options for a future 'Next Generation' European Neutron Source. The CEC has provided support for two Expert Meetings, on Accelerators (at Simonskall near Julich in September 1991) and on Neutron Instrumentation and Techniques (at Abingdon near RAL in February 1992), and a further meeting on Target Technologies was held jointly with PSI at Villigen in early February. The source specification was based on a proton accelerator producing 5 MW of beam power in 1 μs pulses at a repetition rate of 50 Hz. Two target stations were envisaged, one operation at 10 Hz for high resolution and long wavelength instruments and one operating at 50 Hz for high intensity. The conclusions of the three workshops were: - that all accelerator which meets this specification is technically possible; - that an appropriate target-moderator system can be built; - that such a source, having a performance substantially beyond what is available today at ILL and ISIS, will make significant advances in the existing fields of neutron scattering and will open up new scientific horizons. These meetings defined the R and D programme on accelerators, target/moderator systems and neutron scattering instrumentation that is required to produce a full feasibility study (with preliminary costing) and outlined the scientific case. (author)