title: The design and construction of a high-resolution velocity-map imaging apparatus for photoelectron spectroscopy studies of size-selected clusters.
abstract: A new velocity-map imaging apparatus equipped with a laser-vaporization supersonic cluster source and a time-of-flight mass spectrometer is described for high-resolution photoelectron spectroscopy studies of size-selected cluster anions. Vibrationally cold anion clusters are produced using a laser-vaporization supersonic cluster source, size-selected by a time-of-flight mass spectrometer, and then focused co-linearly into the interaction zone of the high-resolution velocity-map imaging (VMI) system. The multilens VMI system is optimized via systematic simulations and can reach a resolution of 1.2 cm(-1) (FWHM) for near threshold electrons while maintaining photoelectron kinetic energy resolutions (ΔKE/KE) of ~0.53% for higher energy electrons. The new VMI lens has superior focusing power over a large energy range, yielding highly circular images with distortions no larger than 1.0025 between the long and short radii. The detailed design, simulation, construction, testing, and performance of the high-resolution VMI apparatus are presented.
authors.affiliation: Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA.
authors.forename: Iker
authors.initials: I
authors.lastname: León
authors.affiliation: Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Yang
authors.affiliation: Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA.
authors.forename: Hong-Tao
authors.initials: HT
authors.lastname: Liu
authors.affiliation: Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA.
authors.forename: Lai-Sheng
authors.initials: LS
authors.lastname: Wang