Date of Award
6-1991
Degree Name
Master of Arts
Department
Physics
First Advisor
Dr. John A. Tanis
Second Advisor
Dr. Emanual Kamber
Third Advisor
Dr. Alvin Rosenthal
Access Setting
Masters Thesis-Open Access
Abstract
Ionization of helium target atoms by He+ projectiles colliding with helium at energies of 0.125 to 3.0 MeV/u is investigated. Cross sections for single and double ionization, and ratios o f double-to-single ionization are determined for each outgoing projectile charge state, and are compared to previous studies. For the lowest energies investigated, the ratios are consistent with the two-step mechanism in which the projectile interacts separately with each target electron. At the highest energies, the ratios reach nearly constant values indicating approach to the high velocity limit. At these high energies, however, the ratios are all higher than the value predicted by the empirical equation of Knudsen et al. (1984). Furthermore, the constant ratios in the high velocity limit are strongly dependent on the outgoing projectile charge state indicating different amount of electron correlation being responsible for double ionization associated with projectile capture, loss, or no charge change, respectively.
Recommended Citation
Forest, Jun, "Double Ionization of Helium by Intermediate to High Velocity He+ Projectiles" (1991). Masters Theses. 969.
https://scholarworks.wmich.edu/masters_theses/969