Date of Award
8-1998
Degree Name
Doctor of Philosophy
Department
Physics
First Advisor
Dr. Thomas W. Gorczyca
Second Advisor
Dr. Emanuel Kamber
Third Advisor
Dr. Gerald Hardie
Fourth Advisor
Dr. Gordon Berry
Abstract
This dissertation, which is in the area of atomic physics, concentrates on the study of the interaction between VUV-soft X-ray radiation and atoms in the gas phase. The main area of interest is the study of Auger decay in atoms utilizing the process known as the resonance Auger effect, where an inner shell electron is excited to an unfilled orbital followed by the ejection of an Auger electron. The measurements in this thesis were performed by using the high resolution Atomic, Molecular and Optical Physics undulator beam line, which utilizes a spherical grating monochromator at the Advanced Light Source at Lawrence Berkeley National Laboratory. The research focused on three rare gases, argon, krypton and xenon. For argon, high resolution angular-resolved measurements of the 2p —» 4s, 3d, 4d resonant Auger lines have been achieved. By measuring photoelectron spectra simultaneously at two different angles using efficient time of flight spectrometers, the angular distributions anisotropy parameters P have been measured, and relative intensities have been evaluated for each of the resolved final ionic states. For krypton, the resonant Auger decay of all the photoexcited Kr 3dy2^n X nl (n = 5-9) states have been studied using an angle resolved two dimensional photoelectron spectroscopic technique, in which the electron yield was measured as a function of both photon energy and electron kinetic energy. Angular distributions, spectator and shake probabilities have been derived for the Kr 3d 'np —» 4s'I4p'lmp + e‘ (n= 5-9, m = 5-11) resonance Auger decay. The results show that the spectator-core coupling is strong at lower n (n = 5,6) but it lessens for higher n, with a shake up of m = n + l preferred. Finally for xenon, the autoionization resonances and angular distribution of the 4d —» 6p decay spectrum were studied utilizing the Auger resonant Raman effect. Using this technique, (3 parameters of almost all 5p4 (3P, lD, lS) 6p final ionic states were determined. These results contribute to our understanding of atomic structure and dynamics of inner shell processes and hopefully w ill stimulate further experimental and theoretical work.
Access Setting
Dissertation-Open Access
Recommended Citation
Farhat, Ahmad H., "Angle-Resolved Studies of Inner Shell Excitations for Argon, Krypton and Xenon using Third Generation Synchrotron Sources" (1998). Dissertations. 1563.
https://scholarworks.wmich.edu/dissertations/1563