Leveraging new-age x-ray lasers for atomistic insight into ultrafast dynamics

The Linac Coherent Light Source (LCLS) is the world's first hard x-ray free-electron laser (XFEL). It generates ultrabright and ultrashort x-ray pulses to probe fundamental processes in matter, ranging from femtochemistry and structural biology to material physics and warm dense matter. LCLS-II, a new superconducting accelerator that achieved first lasing in 2023, is gearing up to generate up to a million x-ray pulses per second and is now open for early-science user programs. The orders-of-magnitude upgrade in average brightness can now light up atoms and molecules in action with unprecedented signal-to-noise and significantly faster data acquisition times. This would facilitate exploring elusive signals, potentially complex experimental designs and systematic scanning of parameter spaces. I will report on recent developments and planned upgrades in the near future with focus on ultrafast chemistry probed with x-ray scattering and spectroscopy to engage with potential scientific users interested in leveraging next-generation transformational x-ray sources.