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Kambic, G. X.

Publications and source records attributed to Kambic, G. X..

Computed tomographic analysis of meteorite inclusions

The feasibility of obtaining nondestructively a cross-sectional display of very dense heterogeneous rocky specimens, whether lunar, terrestrial or meteoritic, by using a fourth generation computed tomographic (CT) scanner, with modifications to the software only, is discussed. A description of the scanner, and of the experimental and analytical procedures is given. Using this technique, the interior of heterogeneous materials such as Allende can be probed nondestructively. The regions of material with high and low atomic numbers are displayed quickly; the object can then be cut to obtain for analysis just the areas of interest. A comparison of this technique with conventional industrial and medical techniques is made in terms of image resolution and density distribution display precision.

Arnold, J. R.↗

A heavy ion beam probe system for investigation of a modified Penning discharge

An ion beam probe diagnostic system can measure time- and space-resolved profiles of plasma space potential and electron density. In combination with a computer iterative technique, the ion beam probe can determine both the space potential profile in plasmas containing strong electric fields and potentials comparable in magnitude to the energy of the probing ion beam. During ion beam probing of a modified Penning discharge, several groups of secondary ions were observed coming from the plasma with a fixed primary beam energy and momentum. The energies of these ions were within 10 percent of the values predicted by a computer-generated model of the potential profile in the plasma. The mechanical and electronic components of the system are described, with particular emphasis on those features required to probe plasma potentials comparable in magnitude to the ion beam energy.

Kambic, G. X.↗

Heavy ion beam probe measurements of radial potential profiles in the Modified Penning discharge

The reported measurements were conducted with the primary beam of an ion beam probe in a plasma discharge in which the space potential represents a large fraction of the primary beam energy. A Lewis ion beam probe similar to the device employed by Jobes et al. (1969) was used in the investigation. The apparatus used in the experiments is discussed along with the experimental procedure. The approximate radial potential profile was obtained by observing the effect of the plasma on the trajectory of the primary beam.

Kambic, G. X.↗

Heavy ion beam probe measurements of radial potential profiles in the modified Penning discharge

A heavy ion beam probe was used to examine the radial potential profile of a plasma in the modified Penning discharge. The plasma has strong (approximately kV) electrostatic potentials near the anode ring which can be a large fraction of the injected ion beam energy. A primary (singly ionized) thallium ion beam is injected through the plasma in the midplane of a double Penning anode ring. After passage through the plasma, primary and secondary (doubly ionized) ions are detected with either a set of flat probes or an electrostatic energy analyzer. A calculation of the primary orbit through the plasma is performed to obtain an approximation to the measured primary beam trajectory. As the real radial potential profile is unknown, an adjustable model is used in the computer program. The adjustable potential profile is varied until the best agreement between measured and calculated trajectories is obtained. Secondary orbits are also predicted using the best fitting adjustable profile. The calculations indicate that secondary beams originating at more than one point in the plasma can be simultaneously observed at the electrostatic analyzer with certain primary beam initial conditions.

Kambic, G. X.↗