A new facility for fundamental particle physics: The high-intensity ultracold neutron source at the Paul Scherrer Institute.

The fundamental properties of the neutron can be studied in detail using ultracold neutrons (UCN) which can be stored and observed for hundreds of seconds. A new user facility providing ultracold neutrons for fundamental physics research has been constructed at the Paul Scherrer Institute, the PSI UCN source. Assembly of the facility finished in December 2010 with the first production of ultracold neutrons. The layout of the source and its operation are briefly discussed. [ABSTRACT FROM AUTHOR]