A magnetic remoderation system with both incident and reemitted positron beams normal to the moderator surface is presented. Incoming 5 keV positrons are focussed by a single pole lens to an aberration limited spot on the remoderator. Reemitted positrons are extracted along the same axis at a lower energy before being separated from the incoming beam by a toroidal deflector. The single pole lens used is very well suited to different types of positron beam measurements. Its major advantage being that the space around the target can be kept free of both material and electric fields, while maintaining a short focal length. For the outgoing beam, the lens has a parallising action, suggesting applications in reemission positron and positron annihilation Auger electron spectroscopy.
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