(e, 2e) electron momentum spectrometer with high sensitivity and high resolution

A high sensitivity and high resolution (e, 2e) electron momentum spectrometer with simultaneous detection in energy and momentum are constructed. The design and performance of the spectrometer are reported. The orbital electron density distributions are obtained accurately and rapidly by using this spectrometer equipped with a double toroidal analyzer. The experimental results on argon and helium exhibit the significant improvements in coincidence count rates, resolution, sensitivity and obtainment of a wide range of adjustable experimental impact energies, which are crucial for further electron momentum spectroscopy studying electronic structure and electron correlation in complex systems. (c) 2005 American Institute of Physics.