Parametric Study of the Performance of an Electrostatic Analyzer With an Hemispheric Field‐of‐View Based on the Donut Topology

Abstract We carried out a parametric study of the optical performance of an electrostatic analyzer based on the donut topology. The instantaneous hemispheric field‐of‐view of the optics eliminates the need of electrostatic deflectors, which are usually added to the energy analyzer in other designs to cover such a wide field‐of‐view. Parametrization of the donut topology and the use of parallel computing have enabled a wide parametric study of the instrument's performance as a function of the angle resolution of the instrument. We have identified a limited number of geometric parameters, including the outer radius of the detection system, which determine the geometric factor and energy resolution of the instrument for a given angular resolution. The average geometric factor per pixel of this 3D plasma camera varies in the range with an energy resolution between 9% and 14% for an energy limit of 20 keV. Our results suggest that a wide range of space missions could benefit from this new instrument concept. A low‐angular‐resolution version of the instrument could be installed on a nano‐satellite platform, for example, for space weather monitoring on low‐Earth orbit. For space missions requiring high‐angular‐resolution measurements, a high‐temporal‐resolution plasma camera would be able to provide the detailed distribution function of charged particles on larger platforms.