TFAS (a tophat for all species): design and computer optimization of a new electrostatic analyzer

Abstract
TFAS (tophat for all species) is discussed. It is a 360 degrees field-of-view electrostatic analyzer that can process particles of either charge simultaneously. The TFAS analyzer resembles two tophat analyzers placed hat to hat, but with the tophat plates removed and the tophat region shared in common by both analyzers. In the tophat region, deflection is by parallel plates, one with potential +V and the other with potential -V. A collimator allows particles to enter this parallel plate region and the particles are then deflected into the spherical deflection region of the analyzer. The TFAS has characteristics comparable to the spherical tophat analyzer. A mathematical analysis is presented showing the optimal dimensions selection for the TFAS analyzer, given a particular tophat angle. Raytracing simulations have been performed. Design curves showing various analyzer characteristics as a function of tophat angle are presented. The design curves are compared to similar curves already in the literature for the spherical tophat analyzer. Differences between the TFAS analyzer and the spherical tophat analyzer are summarized.<>