The chamber is based on a 150 mm O.D. central tube which permits an effective lens
working distance of 80 mm to be achieved, and provides ample space for a mirror to
redirect light from the face of the target up into the vertically mounted microscope.
The main tube size permits large horizontal ports for a vacuum load-lock for sample
changing, using a magnetically coupled transfer arm, a sample goniometer and a gamma-ray
detector. There are also small ports for two X-ray detectors, particle detectors,
X-ray absorber filter magazine controls, transmitted light illumination, view ports and
electrical feedthroughs [1,2,3].
The microscope used is a Questar SZ-100, a catadioptric reflecting microscope with a
150 mm working distance and a minimum field of view (using a 0.5" CCD camera) of 360 µm.
feature of the SZ-100 is the remote control of the microscope focus and step-zoom
controls. The SZ-100 also provides coaxial reflected light illumination. Transmitted
light illumination is also provided.
The target goniometer provides X travel of 100 mm and
Y,Z travel of 50 mm, and options for axial rotation and a second rotation
degree of freedom using a coaxial linear drive. All axes (X,Y,Z,theta,phi) use stepper motor
drives and computer control. The X and Y axes use micro-stepping to provide resolutions
of 0.6 and 0.08 µm, respectively. The rotation axes have a resolution of 0.01°.
The Amiga control software maintains a list of points and scan areas for analysis.
 C.G. Ryan, D.N. Jamieson, W.L. Griffin, G. Cripps and R. Szymanski, "The New
CSIRO-GEMOC Nuclear Microprobe: First Results, Performance and Recent Applications",
Nucl. Instr. Meth. B181 (2001) 12-19.
 C.G. Ryan, D.N. Jamieson, W.L. Griffin and G. Cripps, "The CSIRO-GEMOC Nuclear Microprobe:
A high-performance system based on a new closely integrated design", Nucl. Instr. Meth. B158 (1999) 97-106.
 C.G. Ryan, D.N. Jamieson, W.L. Griffin, S.H. Sie, G. Cripps and G.F. Suter, "The new CSIRO-GEMOC
Nuclear Microprobe: A new highly integrated design for geoscience applications", proc.
10th Australian Conf. on Nuclear Techniques of Analysis, Canberra, ISSN 1329-8437 (1997) NTA/VSA8.