Design of a high-resolution angle-resolving photoelectron spectrometer system

The design and construction details, along with performances, of an angle-resolving electron spectrometer specifically designed for use on the Synchrotron Radiation Research Center in Taiwan are described. The spectrometer is a 160 degrees spherical deflecting-type analyzer with a mean radius of 36.5 mm, including input and output lenses in order to enhance the energy resolution and the count rates. Two real apertures defining an acceptance angle and a probe area are located in the field free region ahead of the input lens, and the entrance and exit apertures of the spherical deflecting sector are set to be virtual. In the design, constant angular resolution, constant energy resolution, and constant transmission are achieved by the spectrometer. The performance of the spectrometer has been tested and is in good agreement with the theoretical calculations.