PSI status 2008-Developments at the 590 MeV proton accelerator facility

The PSI accelerator, a 590 MeV/51 MHz ring cyclotron, routinely delivers 2.0 mA of proton current, which makes it the most powerful machine of this kind worldwide. An upgrade program will boost the current to 2.6 mA and ultimately to 3 mA, in a time frame of 4-5 years from now. Priority applications nowadays are muon spectroscopy (μSR) and neutron scattering. Six μSR-instruments are in operation, and the Swiss spallation neutron source SINQ hosts 15 instruments serving neutron scattering and imaging. PSI always seeks for options to improve the performance of the spallation target to optimized neutron production and reliability at high-power levels. In this context, MEGAPIE (MEGAwatt PIlot Experiment), a liquid metal target for SINQ, is the most recent outstanding project. In the near future, batches of 1% duty cycle of the full proton beam will be deflected to a new Ultracold Neutron source which is currently under construction and will be a key tool for particle physics at PSI.