PARALLEL, MULTICHANNEL ENERGY AND ANGLE RESOLVING ELECTROSTATIC ELECTRON ANALYZER

A new charged particle analyzer offering parallel and multichannel det ection of a range of emitted energy and angle is described. Simultaneo us multiplex detection of both these variables is achieved with the us e of a two-dimensional position sensitive detector. The instrument is so arranged that angular information is recovered from the azimuthal c oordinate, and energy from the radial coordinate of each detected part icle. The instrument is based upon the original 'Bessel Box' design of Alien and co-workers and shares many of the favorable characteristics of that analyzer. General theoretical principles are considered and a ssessed, and then the actual performance of a specific device, fabrica ted for use in an angle resolved UV photoelectron-photoion coincidence experiment is reported. Simple in situ control of the operational mod e of the instrument is described and demonstrated with the prototype, allowing convenient selection of the most effective compromise between resolution and bandwidth. (C) 1995 American Institute of Physics.