PARALLEL, MULTICHANNEL ENERGY AND ANGLE RESOLVING ELECTROSTATIC ELECTRON ANALYZER

A new charged particle analyzer offering parallel and multichannel detection of a range of emitted energy and angle is described. Simultaneous multiplex detection of both these variables is achieved with the use of a two-dimensional position sensitive detector. The instrument is so arranged that angular information is recovered from the azimuthal coordinate, and energy from the radial coordinate of each detected particle. 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 assessed, and then the actual performance of a specific device, fabricated for use in an angle resolved UV photoelectron-photoion coincidence experiment is reported. Simple in situ control of the operational mode 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.