Present status and upgrade plans for ISIS

ISIS, the spallation neutron source, has run for neutron scattering research for extended periods during the last year. It has run regularly with a mean current of 28-32 μA at 550 MeV. Efficiencies of transmission of the beam from injector through the synchrotron to the neutron production target have been good. The system for collecting beam lost in the synchrotron is working well. Modifications are in hand in the present shut-down to increase the proton energy to its design 800 MeV and to increase the current from its present 15% of design to 200 μA mean. Under the umbrella of a Memorandum of Understanding signed by Ministers from France, Italy, Sweden and the UK an International ISIS Project Group with members from the above countries and others has produced a technical report with various costed options for development of ISIS beyond its present specification. Following appraisal by the International Science Advisory Group this report is expected to form the basis of the presentation to Governments proposing a fully international ISIS program