Biggest X-Ray Laser in the World Generates its First Laser Light (2 of 2) (image) Deutsches Elektronen-Synchrotron DESY Share Print E-Mail Caption View into the 2.1-kilometer long accelerator tunnel of European XFEL with the yellow superconducting accelerator modules hanging from the ceiling. Credit Credit: DESY/D. Nölle Usage Restrictions Free for use by the media if reporting on the European XFEL Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.