Examples for Research

Cluster physics
Clusters are tiny collections of atoms or molecules.The picture shows the model calculation of a copper particle with the size of 17000 atoms - a cluster which plays a role in catalytic processes. (Source: DESY in Hamburg)

Cluster experiment at a free-electron laser
First cluster experiment at the free-electron laser of the TESLA Test Facility at DESY. (Source: DESY in Hamburg)

Cluster experiments
When matter is irradiated with very intense light, unusual processes occur, which do not happen after irradiation with less intense light.
Top: A cluster of a few hundred Xenon atoms is irradiated with light flashes from a "conventional" light source and absorbs one high-energy photon. Excited by this energy, an electron is ejected from the cluster leaving a positively charged Xenon cluster behind.
Bottom: A Xenon cluster is irradiated with the intense light flashes of a free-electron laser and absorbs many high-energy photons. At first, some electrons leave the cluster. Yet the process continues: due to irradiation with such highly intense light, the cluster continuously absorbs new photons. Thus, the electrons reach highly excited energy states. However, only rarely do they have enough kinetic energy to leave the cluster completely. According to model representations of physicists, a so-called nanoplasma forms after a few femtoseconds (Am: millionths of a billionth of a second oder quadrillionths of a second oder GB: thousandths of a billionth of a second): The positively charged Xenon cluster is surrounded by a negatively charged "cloud" of high-energy electrons, which may linger a certain distance away from the cluster but are still confined by the positive charge.
When - in this manner - more and more electrons leave the cluster and are confined in the cloud, also more and more positively charged Xenon ions emerge. These ions can even be multiply charged. They all repulse each other so strongly that the cluster "explodes" and the Xenon ions speed into all directions. (Source: DESY in Hamburg)

"Filming" chemical reactions
"Filming" chemical reactions using ultra-fast lasers. (Source: DESY in Hamburg)

Femtochemistry
A chemical reaction is triggered by a laser flash-molecules are excited to a more energetic state. Thereafter they "drop" back to their less energetic equilibrium state. A second laser pulse is then sent at varying intervals (t) after the first one to take instantaneous snapshots of the changes that have occurred in the molecule. (Source: DESY in Hamburg)

Structural biology
This protein DNA complex was investigated at the Hamburg Outstation of the European Laboratory for Molecular Biology (EMBL) with the protein crystallography method. But multiple protein DNA complexes are often very large and therefore difficult to crystallise. To unravel their structure and function in the living organism the X-ray laser opens new possibilities without the need for conventional crystallography. (Source: EMBL Hamburg)

"Explosion" of a biomolecule
Biomolecules are destroyed by intense X-ray radiation: they "explode". The illustration shows a simulation of this process. In order to obtain a usable image of the biomolecule, the image must be recorded very quickly before the sample is destroyed. (Source: DESY in Hamburg)

Plasma physics
With an X-ray laser, plasmas can be created that are as hot as the interiors of giant stars. At the same time, it will be possible to investigate the plasmas so created at varying intervals with another part of the laser beam and thus to conduct research into the plasma state. (Source: DESY in Hamburg)

Plasma experiment
With an X-ray laser, plasmas can be created that are as hot as the interiors of giant stars. At the same time, it will be possible to investigate the plasmas so created at varying intervals with another part of the laser beam and thus to conduct research into the plasma state. (Source: DESY in Hamburg)