The Linac Coherent Light Source (LCLS) X-ray light source has been upgraded with a new delta undulator which can produce light with any selected polarization to better characterize materials. An update version of the delta undulator is under development and will produce x-rays that are 10,000 times brighter than the current system.


Left: Electrons wiggle between two rows of magnets in a traditional undulator, creating X-rays. These X-rays, or light waves, are linearly polarized. Right: With four moving rows of magnets, the Delta undulator can create circularly polarized, or spiraling, light. (Source: SLAC National Accelerator Laboratory)