Publication Date


Advisor(s) - Committee Chair

Martin Longmire, James Parks, George Moore

Degree Program

Department of Physics and Astronomy

Degree Type

Master of Science


This investigation was undertaken in order to confirm and to extend earlier studies of processes whereby energy and angular momentum are transferred from external to internal degrees of freedom in low velocity collisions between ions and atoms. Specifically, this investigation sought to verify the proper functioning of a device designed to study low velocity atomic and molecular collisions, to confirm results obtained in an earlier study of spectra produced by collisions of He+ions with argon atoms, and to extend the energy and wavelength ranges of this study to 1500 eV and 6200 Å, respectively.

The data was in the form of stripchart recordings taken at five beam energies, 600 eV, 800 eV, 1000 eV, 1250 eV, and 1500 eV. A basic analysis of this data was carried out; i.e., lines were identified, their wavelengths determined, and intensities calculated. In addition, the energy dependencies of the emission cross sections of twelve fully resolved lines were plotted and a partial Grotian diagram was drawn.

The apparatus was frund to be functioning properly at energies about 609 eV but not a lower energies. Lipeles' energy and wavelength ranges were extended successfully, and in several instances his findings were confirmed (cf. Lipeles 1971). The visible Ar II spectrum was quite rich with twenty-nine lines being observed, six of which had not been detected previously. In addition, a single line was observed from neutral argon and a single band from molecular nitrogen, a contaminant in the argon target gas.


Atomic, Molecular and Optical Physics | Physical Sciences and Mathematics | Physics