FLASH, acronym of
Free Electron LASer in Hamburg, a
particle accelerator-based soft
X-ray laser located at the
DESY accelerator facilities in
Hamburg,
Germany. It can generate very powerful, ultrashort pulses (~10
-14 s) of coherent radiation in the energy range 10 eV (
electronvolt) to 200 eV. It started operation for external users in the year 2005 and is used for surface, molecular and atomic physics experiments. Intended applications are also the imaging of single biological complex
molecules with time resolution.