Doctoral Dissertations

Keywords and Phrases

Coherence Length; Differential Cross Sections; Ionization; Single-Center Interference; Two-Center Interference; Wave Packet

Abstract

"It has been well established, that projectile coherent properties are important for the study of atomic fragmentation processes. Recent studies of ionization of molecular hydrogen had demonstrated that measured double differential cross sections (DDCS) are very sensitive to the coherent length of the projectile. These measurements have been performed with varied coherence length of the projectiles by controlling the geometry of the collimating slits, which are placed before the target. Later, fully differential cross sections (FDCS) for a coherent and an incoherent projectile beam has been study for the same collision system and the results confirmed the important role of intrinsic projectile coherence properties. In the study, a new insight into the interference term as a function of the phase angle was obtained. By analyzing the FDCS as a function of the momentum transfer and of the recoil-ion momentum, single-center interference and two-center interference were identified and separated from each other. Single-center interference could be studied selectively and in detail by measuring FDCS for ionization of helium, because two-center interference is obviously absent. Ab initio calculations were able to well reproduce the data, in which the projectiles are described by a wave packet of varying width. This comparison shows that single-center interference is due to a coherent superposition of a range of impact parameters leading to the same scattering angle"--Abstract, page iv.

Advisor(s)

Schulz, Michael

Committee Member(s)

Madison, Don H.
Peacher, Jerry
Fischer, Daniel
Samaranayake, V A.

Department(s)

Physics

Degree Name

Ph. D. in Physics

Publisher

Missouri University of Science and Technology

Publication Date

Summer 2016

Journal article titles appearing in thesis/dissertation

  • Separation of single-and two-center interference in ionization of H2 by proton impact
  • Influence of the post-collision interaction on interference effects in ionization of H2 by proton impact
  • Fully differential study of ionization in p + H2 collisions near electron - projectile velocity matching
  • Fully differentials study of wave packet scattering in ionization of Helium by proton impact

Pagination

x, 86 pages

Note about bibliography

Includes bibliographic references.

Rights

© 2016 Thusitha Priyantha Arthanayaka, All rights reserved.

Document Type

Dissertation - Open Access

File Type

text

Language

English

Library of Congress Subject Headings

Ionization
Collisions (Nuclear physics) -- Mathematical models
Nuclear fragmentation
Electron impact ionization
Cross sections (Nuclear physics)
Wave packets

Thesis Number

T 10945

Electronic OCLC #

958280628

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