European XFEL X-Ray Optics Group projects and challenges

The European X-Ray Free-Electron Laser Facility (European XFEL), an X-Ray research laser facility, was first commissioned in 2017. The European XFEL accelerator can accelerate electrons up to 17.5 GeV. Electron bunch trains are produced at a repetition rate of 10Hz. Every train can consist of up to 2700 electron bunches; thus, up to 27000 X-Ray pulses can be generated per second for use in scientific experiments. The facility is aiming for continuous improvement and upgrades, despite the peculiar challenges and low availability of some special optical components. We list some representative projects that are either already accepted or proposed and are involving the Optics Group at XFEL.