Design of a parallel-plate energy spread analyzer

A 45° parallel-plate energy spread analyzer has been designed and built for the ISAC project at TRIUMF. It features an energy resolution of ⩽0.04% and a spectrometer constant of k=1.29. Nineteen 0.1 mm by 10 mm metal guard frames with 1 MΩ resistors are used to equalize the electric field in the analyzer to an order of ⩽0.5%. Electric field simulation is done by a code POISSON. This article describes the design of the analyzer. Preliminary experimental results are also presented.