Pump–probe experimental methodology at the Linac Coherent Light Source. (10th May 2019) - Glownia, James M.
Abstract : Techniques developed at LCLS to make optical laser pump–X‐ray probe experiments both robust and easy to implement at ultrafast X‐ray free‐electron lasers are presented. Abstract : Experimental methods that use free‐electron laser (FEL) sources that can deliver short X‐ray pulses below a 10 fs pulse duration and traditional optical lasers are ideal tools for pump–probe experiments. However, these new methods also come with a unique set of challenges, such as how to accurately determine temporal overlap between two sources at the femtosecond scale and how to correct for the pulse‐to‐pulse beam property fluctuations of the FEL light derived from the self‐amplified spontaneous emission process. Over the past several years of performing pump–probe experiments at the Linac Coherent Light Source (LCLS), new methods and tools have been developed to improve the ways experimental timing is measured, monitored and scanned. The aim of this article is to present an overview of the most commonly used techniques at LCLS to perform pump–probe‐type experiments.