Non-intrusive flow diagnostics are essential for studying the physics of hypersonic flow wake regions. To advance the development of next generation hypersonic vehicles and to improve computational fluid dynamics techniques in the hypersonic regime, NASA needs a suitable non-intrusive diagnostic technique to measure velocity, density, and temperature. We will present our work on developing a seedless, non-intrusive diagnostic technique using excited state argon atoms, prepared via multi-photon excitation. In this dissertation, we report results on the first phase of this hypersonic wake measurement project. In particular, we have redesigned and characterized the performance of a high energy, nanosecond pulsed Ti:Sapphire laser. Using this laser, we have studied in argon, a three-photon excitation that yields a long-lived metastable state via radiative decay. Our measurements were conducted over a range of pressures both with and without a krypton buffer gas. We compare our measured results to detailed calculations of the excitation pathway and describe the physical processes that govern the excitation and decay processes. Finally, we provide a roadmap for the next phase of the project.
","abstract_html":"<p>Non-intrusive flow diagnostics are essential for studying the physics of hypersonic flow wake regions. To advance the development of next generation hypersonic vehicles and to improve computational fluid dynamics techniques in the hypersonic regime, NASA needs a suitable non-intrusive diagnostic technique to measure velocity, density, and temperature. We will present our work on developing a seedless, non-intrusive diagnostic technique using excited state argon atoms, prepared via multi-photon excitation. In this dissertation, we report results on the first phase of this hypersonic wake measurement project. In particular, we have redesigned and characterized the performance of a high energy, nanosecond pulsed Ti:Sapphire laser. Using this laser, we have studied in argon, a three-photon excitation that yields a long-lived metastable state via radiative decay. Our measurements were conducted over a range of pressures both with and without a krypton buffer gas. We compare our measured results to detailed calculations of the excitation pathway and describe the physical processes that govern the excitation and decay processes. Finally, we provide a roadmap for the next phase of the project.</p>","abstract_has_math":false,"creators":["Mills, Jack L."],"institution":null,"degree_name":"Doctor of Philosophy (PhD)","degree_level":"Dissertation","degree_discipline":"Physics","degree_department":null,"school":null,"contributors":["Charles I. Sukenik","R. Jeffery Balla","Lepsha Vuskovic","Ted Rogers","Gordon Melrose"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2016,"date_issued":"2016-10-01T07:00:00Z","date_published":"2016-10-01T07:00:00Z","updated_at":"2026-07-24T03:34:02Z","subjects":["Flow diagnostics","Fluid dynamics","Hypersonic flow wake regions","Hypersonic vehicles","Ti:Sapphire laser","Atomic, Molecular and Optical Physics"],"languages":[],"rights":["In Copyright. URI: http://rightsstatements.org/vocab/InC/1.0/ This Item is protected by copyright and/or related rights. You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s).
"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["9781369560152"],"render_values":[{"text":"9781369560152","href":null,"code":true}]}]},"links":{"outbound_url":"https://digitalcommons.odu.edu/physics_etds/5","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Charles I. Sukenik","R. Jeffery Balla","Lepsha Vuskovic","Ted Rogers","Gordon Melrose"]},{"key":"dc:creator","label":"Author","values":["Mills, Jack L."]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.available","label":"Dc Date Available","values":["2017-02-08T08:00:00Z"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Physics"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Doctor of Philosophy (PhD)"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Flow diagnostics","Fluid dynamics","Hypersonic flow wake regions","Hypersonic vehicles","Ti:Sapphire laser","Atomic, Molecular and Optical Physics"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:rights","label":"Dc Rights","values":["In Copyright. URI: http://rightsstatements.org/vocab/InC/1.0/ This Item is protected by copyright and/or related rights. You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s).
"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["9781369560152","https://digitalcommons.odu.edu/physics_etds/5"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Non-intrusive flow diagnostics are essential for studying the physics of hypersonic flow wake regions. To advance the development of next generation hypersonic vehicles and to improve computational fluid dynamics techniques in the hypersonic regime, NASA needs a suitable non-intrusive diagnostic technique to measure velocity, density, and temperature. We will present our work on developing a seedless, non-intrusive diagnostic technique using excited state argon atoms, prepared via multi-photon excitation. In this dissertation, we report results on the first phase of this hypersonic wake measurement project. In particular, we have redesigned and characterized the performance of a high energy, nanosecond pulsed Ti:Sapphire laser. Using this laser, we have studied in argon, a three-photon excitation that yields a long-lived metastable state via radiative decay. Our measurements were conducted over a range of pressures both with and without a krypton buffer gas. We compare our measured results to detailed calculations of the excitation pathway and describe the physical processes that govern the excitation and decay processes. Finally, we provide a roadmap for the next phase of the project.
"]},{"key":"dc:title","label":"Title","values":["Investigation of Multi-Photon Excitation in Argon with Applications in Hypersonic Flow Diagnostics"]}]}],"canonical_facts":{"dc:contributor":["Charles I. Sukenik","R. Jeffery Balla","Lepsha Vuskovic","Ted Rogers","Gordon Melrose"],"dc:creator":["Mills, Jack L."],"dc:date.available":["2017-02-08T08:00:00Z"],"dc:description.abstract":["Non-intrusive flow diagnostics are essential for studying the physics of hypersonic flow wake regions. To advance the development of next generation hypersonic vehicles and to improve computational fluid dynamics techniques in the hypersonic regime, NASA needs a suitable non-intrusive diagnostic technique to measure velocity, density, and temperature. We will present our work on developing a seedless, non-intrusive diagnostic technique using excited state argon atoms, prepared via multi-photon excitation. In this dissertation, we report results on the first phase of this hypersonic wake measurement project. In particular, we have redesigned and characterized the performance of a high energy, nanosecond pulsed Ti:Sapphire laser. Using this laser, we have studied in argon, a three-photon excitation that yields a long-lived metastable state via radiative decay. Our measurements were conducted over a range of pressures both with and without a krypton buffer gas. We compare our measured results to detailed calculations of the excitation pathway and describe the physical processes that govern the excitation and decay processes. Finally, we provide a roadmap for the next phase of the project.
"],"dc:identifier":["9781369560152","https://digitalcommons.odu.edu/physics_etds/5"],"dc:rights":["In Copyright. URI: http://rightsstatements.org/vocab/InC/1.0/ This Item is protected by copyright and/or related rights. You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s).
"],"dc:subject":["Flow diagnostics","Fluid dynamics","Hypersonic flow wake regions","Hypersonic vehicles","Ti:Sapphire laser","Atomic, Molecular and Optical Physics"],"dc:title":["Investigation of Multi-Photon Excitation in Argon with Applications in Hypersonic Flow Diagnostics"],"thesis:degree_discipline":["Physics"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Doctor of Philosophy (PhD)"]},"updated_at":"2026-07-24T03:34:02Z"}