Recommended Practice for the Use of Electrostatic Analyzers in Electric Propulsion Testing
Electrostatic analyzers are used in electric propulsion to measure the energy per unit charge E/q distribution of ion and electron beams: in the downstream region of thrusters, for example. This paper serves to give an overview of the most fundamental, yet most widely used, types of electrostatic analyzer designs. Analyzers are grouped into two classifications: 1) mirror-type analyzers, and 2) deflector-type analyzers. Common mirror-type analyzers are the parallel-plate mirror analyzer and the cylindrical mirror analyzer. For deflector-type analyzers, a generalized toroidal type is first described and the commonly used cylindrical deflector and spherical deflector analyzers are discussed as special cases. The procedure for energy resolution calculations of electrostatic analyzers is described, which is a common way of comparing analyzers. Ion energy distributions from a spherical deflector analyzer are presented, comparing variations in 1) particle energy, 2) particle angle, 3) the entrance and exit geometry of the analyzer, and 4) sector angle using numerical calculations.
Journal of Propulsion and Power