With its outstanding diversity of light sources, DESY is one of the world’s leading centres for science with photons. Other similar research institutes typically have just one accelerator available as a light source, which is set up to provide specific radiation properties. At DESY, however, both the existing and planned light sources complement one another perfectly. Scientists working at DESY therefore have access to exactly the type of radiation they need for their experiments.

Light sources at DESY

DORIS III

For several decades, scientists have conducted research using the very intense light from the DORIS storage ring at DESY. DORIS has been in operation since 1974 – initially both for particle physics and for research with synchrotron radiation. In 1990 and 1991 the storage ring was expanded to make room for seven additional magnet structures, so-called wigglers and undulators. This modified machine, DORIS III, has been used exclusively as a source of synchrotron radiation since 1993.

The results of this period have been substantial. Time and again, the scientists and engineers at DORIS were able to develop new methods and instruments and to achieve breakthrough results that opened new fields of research. In many cases, what began as a local test experiment developed into a successful experimental method that ultimately established itself worldwide as a standard method used in research and industrial applications.

FLASH

Since 2005 researchers at DESY have had access to a unique new type of light source: FLASH, the world’s only free-electron laser to generate radiation in the vacuum ultraviolet and soft X-ray regions. This is a pioneering facility in a number of ways. As the world’s first-ever X-ray free-electron laser with a superconducting linear accelerator, FLASH is a source of indispensable knowledge for the development of future accelerators and X-ray lasers. At the same time, it provides researchers from virtually all the natural sciences with unprecedented experimental possibilities.

Initial usage of FLASH soon resulted in some spectacular new experiments, and the scientific interest is correspondingly intense. As a user facility, FLASH offers a total of five experimental stations where different instruments can be set up as required. At the same time, the operation of FLASH generates important knowledge for the forthcoming XFEL X-ray laser and similar light sources worldwide.

PETRA III

For a number of years the 2.3-kilometre-long PETRA storage ring was used for particle physics experiments and to provide test experimental stations with hard X-rays for science with photons. meanwhile, however, PETRA is dedicated solely to generating light. In summer 2007 work began on the modification of the facility. In 2009, it commenced operation under the new name of PETRA III as one of the most brilliant storage-ring-based X-ray radiation sources worldwide.

Almost 300 metres of the ring had to be completely rebuilt and a new experimental hall was constructed. In the final stage, PETRA III will provide 14 experimental stations with up to 30 instruments. The installation of several specially adapted undulators delivering X-ray radiation of an especially high brilliance guarantees excellent research opportunities for users from around the world.

European XFEL

An absolute highlight in the genuine sense of the word is the forthcoming X-ray free-electron laser European XFEL, which is being realized as a European project with strong DESY participation in the Hamburg region and is due to start up in 2014. As the only light source of its kind in Europe, the European XFEL will generate extremely intense, ultra-short pulses of laser light in the X-ray range at wavelengths substantially shorter than even the light generated by FLASH. The European XFEL will therefore open up a whole new realm of highly promising research opportunities for almost all the natural sciences.

The 3.4-kilometre-long facility, which is currently under construction, extends from DESY in Hamburg to the Schleswig-Holstein town of Schenefeld in the Pinneberg district, where the research campus comprising an experimental hall and space for ten experimental stations will be located. The European XFEL was approved in principle in February 2003. In June 2007 the German research ministry gave the go-ahead for the construction of an initial version with six experimental stations, to be funded by Germany and international partners. Civil construction began on 9 January 2009, the start of commissioning is scheduled for 2014.