The CSIRO-GEMOC Nuclear Microprobe: a high-performance system based on a new closely integrated design

A new Nuclear Microprobe (NMP) has been developed at the CSIRO in collabora tion with GEMOC and the University of Melbourne, to better exploit advanced techniques that are unique to the NMP, as a complement to the developing r ange of microanalytical techniques available in geology. The new probe uses a new design that closely integrates the beam forming lens system with the chamber, microscope and detector systems to provide good focussing perform ance, a normal viewing microscope and large solid-angle detectors. The key to this design is a new quadrupole quintuplet lens system which uses a new design for each quadrupole, with pole-tip extensions and yoke cut-outs for detectors, permitting an effective working distance of SO mm and unrestrict ed access for detectors at 135 degrees. Further features of the new probe i nclude: large area X-ray, gamma-ray and particle detectors, digital signal processors, electrostatic on-demand beam-switching and scanning Questar lon g-range microscope, computer-controlled sample goniometer, sample-change va cuum-lock, anti-vibration mounting and efficient beam shaping using compute r-controlled object and divergence limiting slits. (C) 1999 Elsevier Scienc e B.V. All rights reserved.