Doctoral Dissertations
Date of Award
6-1987
Degree Type
Dissertation
Degree Name
Doctor of Philosophy
Major
Physics
Major Professor
Ivan A. Sellin
Committee Members
J. E. Bloor
Abstract
A novel time-of-flight technique was used to measure average energies of ions produced by inner-shell photoionization of inert-gas atoms with synchrotron radiation in order to investigate the feasibility of developing a Very Cold ion Source (VCIS). Multiply-charged Ne, Ar, Kr, and Xe ions were produced in vacancy cascades following inner-shell photoionization by x rays from a wiggler line at Stanford Synchrotron Raaiation Laboratory, and the resulting charge-state distributions and average kinetic energies were measured using a time-of-flight spectrometer. Ion energies were found to correspond essentially to room temperature, and observed ion intensities show promise for future use in very-low-energy atomic collisions and precision spectroscopy studies.
Recoil energies were similarly measured for Ne and Ar ions produced by swift-ion impact using the EN Tandem accelerator at Oak Ridge National Laboratory. Average energies for the higher charge states were found to be up to 2 orders of magnitude larger than for those produced by photoionization. Impact parameters important in the collision processes were inferred from measured recoil energies using a screened-Coulomb scattering model. Knowledge of recoil-ion energies may be useful for the future development of parasitic low-energy ion sources on heavy-ion accelerators.
Recommended Citation
Short, Robert Timothy, "Recoil-energy measurements of slow highly-charged ions produced by synchrotron radiation and by swift-ion impact. " PhD diss., University of Tennessee, 1987.
https://trace.tennessee.edu/utk_graddiss/12168