X-Ray Pulse (IMAGE) DOE/Lawrence Berkeley National Laboratory Caption A femtosecond x-ray pulse from an x-ray free electron laser intersecting a droplet that contains photosystem II crystals, the protein extracted and crystallized from cyanobacteria. Credit SLAC National Accelerator Laboratory Usage Restrictions Copyright SLAC. Editorial use with credit. Commercial use prohibited. License Licensed content 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.