Dr. Jan GrŸnert is a physicist at the European XFEL facility, and Group Leader of the X-ray Photon Diagnostics (XPD) Group which provides the facility instrumentation for x-ray beam characterization and monitoring. Jan holds laser physics degrees of the Universities of Texas at Austin and Hamburg, Germany. As post-doc at the Paris Observatory, he worked on ultraprecise atomic clocks, then in R&D at Saint-Gobain Sekurit. He joined XFEL in 2008 at the start of construction.