Near Ambient Pressure XPS at ALBA

The ALBA light source has started to operate this year. One of the seven beamlines built in the first phase is the CIRCE beamline (BL24), with two endstations in different branches, dedicated to Photoemission Electron Microscopy (PEEM) and Near Ambient Pressure Photoelectron spectroscopy (NAPP). In this communication we present the NAPP endstation. A differentially pumped electron energy analyzer allows extending the standard Xray Photoelectron Spectroscopy (XPS) technique, which traditionally required ultra-high vacuum (UHV) conditions, to sample pressures up to 20 mbar. The surface reactivity and structure in more realistic environments can reveal dramatic differences with respect to the solid-vacuum studies. A novel differentially pumped system for the photon beam entrance and other state-of-the-art instrumentation built by SPECS GmbH (Berlin, Germany) are briefly described.