Research into tiny, incredibly swift atoms frequently proves challenging, according to Professor Dr. Christian Bressler. Yet this is the daunting task now faced by the scientist and the Femtosecond X-ray Experiments (FXE) team at European XFEL in Schenefeld. A femtosecond is a quadrillionth of a second and the shortest time unit for all chemical processes. “The unit hardly moves in a femtosecond even though the reaction can be explosive,“ Bressler told Hamburg News in an interview. At stake is the precise snapshot.
Researching incredibly swift processes, producing molecular film
The world’s largest X-ray laser, the European XFEL generated the first extremely bright, short X-ray flashes on May 4, 2017. First experiments have already begun for commissioning purposes. User operation for scientific research purposes is scheduled from September 1. FXE is among the first experiments and will allow the scientists to research incredibly swift processes and to produce a molecular film for examining the many interim steps in a fast chemical reaction closely.
Stimulating and photographing
FXE is housed in a lead-sheathed room beside the “Mission Control Center” with all kinds of servers, computers and monitors. Experiments are remote-controlled as the intense radiation makes it impossible for scientists to remain in the hall. An optical laser in a third room provides pulses of red, green and blue flashes of light depending on biochemical processes. The high-power, optical laser is synchronized with the European XFEL pulses and tuneable in both wavelength and pulse duration to the needs of different experiments. Thanks to the synchronisation, the momentary reaction can be photographed. The process is similar to a strobe light in a discotheque that shines momentary bright lights while people dance, said Bressler. “The laser light stimulated in femtoseconds means the molecules all move on the same short time scale,” he added. FXE records the stereotypic behaviour in certain time intervals. “We repeat that incredibly often and then turn these pin sharp still images into a film. That allows us to examine the behaviour of the molecules exactly.” However, Bresseler and his team do not want to simply document processes in nature and are striving to gain a better understanding of the movements.
Stimulating and photographing
The combination of optical, stimulating laser light and the ultra-short X-ray laser light for photographs makes this possible. The findings can be used in diverse fields e.g. research into the molecular processes of illnesses, energy research and improving chemical procedures. “We can, for instance, examine candidates for a new drug and watch exactly what is happening on the molecular level.” This may give insight into possible side effects. “However, the power lies mainly with the X-ray laser.” And while the process is still a long way off, “it is of course an objective,” said Bressler.
Global expertise and exchange
The international team includes 12 scientists and Ph.D. candidates from seven countries whose combined approaches and fresh ideas form the basis of progress and development. Bressler noted: “I would not be the proud group leader of FXE without diverse stints spent abroad. But the team, who hail from all over the world, are crucial to our success.“ The global input helps us to develop new approaches “and if we do not have a specific skill here, we will bring people from all over the world to Hamburg.” However, people’s origins alone are not the key to success and their experience elsewhere is also decisive. “It is inspiring to see diverse approaches to scientific problems before we set up something new.”
Hamburg – top centre of light research
Scientists are expecting spectacular findings from FXE and “then Hamburg will become the world’s top light research centre,” said Bressler. European XFEL is already the world’s brightest X-ray light and is likely to make Hamburg shine for years to come.
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