XPE Spectroscopy (image) DOE/Lawrence Berkeley National Laboratory Caption With photoemission spectroscopy techniques such as HARPES, a beam of x-rays flashed on a sample transfers energy from the photons to electrons, causing photoelectrons to be emitted. Measuring the kinetic energy of these photoelectrons and the angles at which they are ejected reveals much about the sample's electronic structure. Credit Image from Fadley group Usage Restrictions None 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.