The CoESCA station at BESSY: Auger electron–photoelectron coincidences from surfaces demonstrated for Ag MNN
Journal article, 2021

In this work, we present the CoESCA station for electron–electron coincidence spectroscopy from surfaces, built in a close collaboration between Uppsala University and Helmholtz-Zentrum Berlin at the BESSY II synchrotron facility in Berlin, Germany. We start with a detailed overview of previous work in the field of electron–electron coincidences, before we describe the CoESCA setup and its design parameters. The system is capable of recording shot-to-shot resolved 6D coincidence datasets, i.e. the kinetic energy and the two take off angles for both coincident electrons. The mathematics behind extracting and analysing these multi-dimensional coincidence datasets is introduced, with a focus on coincidence statistics, resulting in fundamental limits of the signal-to-noise ratio and its implications for acquisition times and the size of the raw data stream. The functionality of the CoESCA station is demonstrated for the example of Auger electron–photoelectron coincidences from silver surfaces for photoelectrons from the Ag 3d core levels and their corresponding MNN Auger electrons. The Auger spectra originating from the different core levels, 3d and 3d could be separated and further, the two-hole state energy distributions were determined for these Auger decay channels.

Spectroscopy

Coincidence

APECS

PES

Auger

Surface science

AES

Photoelectron

Author

T. Leitner

Uppsala-Berlin joint Laboratory

Helmholtz

A. Born

Helmholtz

University of Potsdam

I. Bidermane

Uppsala-Berlin joint Laboratory

Helmholtz

Ruslan Ovsyannikov

Uppsala-Berlin joint Laboratory

Helmholtz

Fredrik O.L. Johansson

Uppsala University

Yasmine Sassa

Chalmers, Physics, Materials Physics

A. Föhlisch

Uppsala-Berlin joint Laboratory

Helmholtz

Andreas Lindblad

Uppsala University

Uppsala-Berlin joint Laboratory

F. O. Schumann

Max Planck Society

S. Svensson

Uppsala University

Uppsala-Berlin joint Laboratory

N. Martensson

Uppsala-Berlin joint Laboratory

Uppsala University

Journal of Electron Spectroscopy and Related Phenomena

0368-2048 (ISSN)

Vol. 250 147075

Subject Categories

Atom and Molecular Physics and Optics

Other Physics Topics

Condensed Matter Physics

DOI

10.1016/j.elspec.2021.147075

More information

Latest update

5/25/2021