Date of Award
Doctor of Philosophy
Dr. John A. Tanis
Dr. Norah Berrah
Dr. Dean W. Halderson
Dr. Emanuel Y . Kamber
Projectile charge changing and target ionization cross sections are measured for 0.5 to 8 qMeV Li^q+ + He (q=1,2,3) collisions. Total cross sections for single-electron capture (for L i^1,2,3+) and single-electron loss (for L i^1,2+) are obtained and compared to existing experimental and theoretical data. Also, single and double target ionization of He associated with specific outgoing projectile charge states are identified using coincidence techniques. Cross sections for target ionization associated with no projectile charge change (direct ionization), single-electron capture, and single-electron loss are measured and compared to existing experimental data and to available calculations. Double-to-single target ionization ratios R are obtained and interpreted in terms of theoretical formulations involving electron - nucleus interactions and electron - electron interactions. It is found that R for direct ionization is nearly independent of the incident projectile charge state and can be described by the semi-empirical scaling rule of Knudsen et al. (1984). However, the R values associated with single-electron loss and single electron capture by the projectile depend strongly on the incident charge state of the projectile. Furthermore, R for a given incoming projectile charge state varies strongly with the reaction channel. Effective charges for Li^+ and Li2^+ associated with single and double target ionization are also calculated.
In the second part of this dissertation the control program and data acquisition software for an electron spectrometer system utilizing two plane-mirror analyzers (PMA) are described. This system will be used to measure the energy and angle of electrons ejected in ion-atom collisions.
Woitke, Oliver, "Ionization and Charge Changing in 0.5 - 8 qMeV Li^q+ + He (q=1,2,3) Collisions and Setup of an Electron Spectrometer Control System" (1996). Dissertations. 1725.