A new spectrometer at the European XFEL’s small quantum systems (SQS) instrument will measure soft x-ray radiation and extreme ultraviolet (XUV) light generated by gaseous samples after interaction with intense XFEL pulses. This enables fresh avenues of research for the instrument. The spectrometer was built by a collaboration involving scientists from European XFEL and Uppsala University in Sweden, and will allow scientists at SQS to probe new and exciting processes on the atomic scale.
“The spectrometer will give us the ability to look at XUV light emitted from atoms and molecules. Its unique capability to image along the interaction zone enables us to study the effect of European XFEL’s intense X-ray radiation as it travels through dense gases,” says Michael Meyer, leading scientist of the SQS instrument. “It will offer new possibilities to study fundamental processes in the interaction of x-ray radiation with matter.”

Radiation with wavelengths in the extreme ultraviolet (XUV) range is emitted upon excitation or ionization of a sample by the European XFEL pulses. Spectroscopy of these emitted XUV photons is an ideal tool for studying the quantum mechanical properties of the sample in its interaction with the intense X-ray pulses. This is particularly useful in comparison with other techniques based on electron or ion spectroscopy as the photons are not severely impacted by the charged particles created during the interaction.

“At SQS we study fundamental properties of atomic and molecular systems, predominantly looking at electrons and ions. The new spectrometer complements these techniques and helps us to better understand physics on the very small scale,” says Thomas Baumann, scientist at SQS.