Facts and Figures


Total length

3.4 kilometres

The facility runs from the DESY site in Hamburg in a northwestern direction to the town of Schenefeld in Schleswig-Holstein.

Number of sites


The three sites are: DESY-Bahrenfeld (ca. 2 hectares), Osdorfer Born (ca. 1.5 hectares) and Schenefeld (ca. 15 hectares). The research campus is located in Schenefeld.

Depth of the tunnels

6 to 38 metres

The tunnels are covered by at least 6 metres of soil.

Construction costs including preparation and commissioning

1.22 billion euro
(price levels of 2005)

As the host country, Germany (Federation, Hamburg, and Schleswig-Holstein) covered 58% of the construction costs. Russia took over 27% and the other international partners between 1% and 3% of the construction costs each.

European XFEL GmbH

Legal form


The European XFEL was constructed and is operated by the European XFEL GmbH, a non-profit Company of Limited Liability under German law. The company was founded on 28 September 2009.

Annual budget (estimated)

117 000 000 euro

rounded to thousand euro

Staff (under development)

over 300 employees

The European XFEL GmbH has a workforce of over 300 people, about 240 DESY employees operate the accelerator for European XFEL.

Participating countries

currently 11

Denmark, France, Germany, Hungary, Italy, Poland, Russia, Slovakia, Spain, Sweden, and Switzerland participated in the construction and operation of the European XFEL. The United Kingdom is in the process of joining as the twelfth member state.


Start of commissioning


Beginning of testing and preparation of the completed facility for operation

First X-ray flashes


First X-ray flashes are generated from electrons

First proposals


First proposals for experiments at the first two instruments

User Operation


Start of user operation with 1 beamline and 2 experiment stations



Superconducting linear accelerator


Total length

2.1 kilometres


Acceleration length

1.7 kilometres



17.5 billion electron volts

expandable to 20 billion electron volts. This would allow the generation of even shorter wavelengths.


minus 271 degrees Celsius

The accelerator elements are cooled to -271°C using liquid helium. At these temperatures, they conduct electric current without any losses.

Number of modules

96 (+2 in injector)

The electrons are accelerated in accelerator modules comprising several superconducting chambers (called cavities or resonators). In these cavities, an oscillating microwave accelerates the particles. The cavities are surrounded by cooling elements.

Properties of the X-ray laser flashes

Flashes per second

27 000

This high repetition rate is what makes the European XFEL unique among the X-ray lasers in the world. It is only possible thanks to the superconducting accelerator technology.


0.05 to 4.7 nanometres

The wavelengths of the X-ray flashes of the European XFEL are so short that even atomic details become discernible.


less than 100 quadrillionth of a second (less than 100 femtoseconds)

Thanks to this extremely short pulse duration, scientists will be able to film e.g. the formation of molecules or the reversal of magnetization.

Brilliance (peak value)

5·1033 (photons / s / mm2 / mrad2 / 0.1% bandwidth)

The peak brilliance is a billion times higher than that of the best conventional X-ray sources. The brilliance describes the number of photons of a given energy that are emitted per second, area, and angle within a small energy interval.

Brilliance (average value)

1.6·1025 (photons / s / mm2 / mrad2 / 0.1% bandwidth)

The average brilliance is 10 000 times higher than that of the best conventional X-ray sources.



The X-ray flashes have the characteristics of laser light. This makes it possible to take 3D images at the atomic level.