A workshop on the Future Developments of European Muon Sources took place at Cosener’s House, Abingdon, UK on the 2nd and 3rd November 2006. The Workshop was funded as a foresight study through the EC Neutron and Muon Integrated Infrastructure Initiative (NMI3). It aimed to bring together European users of the muon spin rotation, relaxation and resonance techniques to discuss future possibilities for the development of muon sources within Europe. The workshop enabled consideration of current European sources (ISIS, UK and PSI, Switzerland) and their future development plans; developments in the muon technique and their implications for future sources; the extent to which new neutron sources in Europe might be used for muon production; and the further development of a science case to support new muon source initiatives.

The opening session on ‘Present sources, now and in the future’ gave reviews of the current facilities at ISIS (UK), PSI (Switzerland) and TRIUMF (Canada) and their future plans. These include construction of a new high longitudinal field (5T) instrument at ISIS, due to be online at the end of 2008; improvements on the low energy muon beamline at PSI allowing a tuneable implantation depth of 1–200nm and increasing the flux; and plans to increase data rates by the use of multiple pixel detectors and a new, fully-automated beamline at TRIUMF. Also, an interesting idea of using a ‘magnetic leaky bottle’ was presented which could significantly increase the muon flux from the production target.

Consideration of future muon sources in European is very timely. Kurt Clausen, from PSI, showed that opportunities within Europe for new neutron source provision continue to develop, with the inclusion of the ESS project within the European Strategy Forum for Research Infrastructures roadmap for future facilities (http://cordis.europa.eu/esfri/). Bob Cywinski, from Leeds University, presented some very interesting ideas using fixed field alternating gradient (FFAG) accelerators. FFAGs may enable provision of an accelerator-based muon source tailored to the needs of the muon technique. Finally, Chris Warsop, from ISIS, gave a wide range of possible upgrade options to the ISIS facility which could lead to a 3 GeV source.

The session on the muon technique in the future made it clear the method continues to evolve and develop. There are increased possibilities available to technique users – such as the range and combination of thermodynamic variables that can be accessed, the ability to use pulsed stimuli, increasing data rates and decreasing sample size, and use of low energy muons. The coming years will continue to see further developments in these areas and facilities report levels of funding increase that are enabling such technique improvements.

Finally, a wide range of presentations were given to support the science case for future muon sources. These talks showed the variety of investigations that are possible using muons, including studies of reaction kinetics, muoniated free radicals, DNA, ionic conductors, semiconductors, molecular magnets, magnetic materials and superconductors. Implications of studies in these areas for future muon sources were also given.

The Workshop demonstrated that there is considerable potential for future muon developments in Europe. All workshop presentations and the final workshop report are available on the future developments of European Muon Sources website