Development of advanced diagnostics for high energy density plasmas

<p>The field of high-energy density physics explores the properties of matter at extreme conditions, crucial for both astrophysical insights and in the pursuit of fusion energy. However, the complexity of competing forces influencing material behaviour within this regime necessitates experimen...

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Autore principale: Poole, H
Altri autori: Gregori, G
Natura: Tesi
Lingua:English
Pubblicazione: 2024
Soggetti:
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author Poole, H
author2 Gregori, G
author_facet Gregori, G
Poole, H
author_sort Poole, H
collection OXFORD
description <p>The field of high-energy density physics explores the properties of matter at extreme conditions, crucial for both astrophysical insights and in the pursuit of fusion energy. However, the complexity of competing forces influencing material behaviour within this regime necessitates experimental validation of theoretical models. One powerful experimental technique capable of probing the equation of state is Thomson scattering.</p> <p>This thesis investigates the use of Thomson scattering across diverse experimental setups in the high-energy density regime. Bayesian inference techniques are employed for inferring thermodynamic conditions from experimental observations. Firstly, the feasibility of using Thomson scattering to discern in-flight conditions within inertial confinement fusion implosions is presented. Spatially-integrated synthetic scattering spectra are generated to infer information about the inhomogeneous compressed shell under various adiabat capsule conditions. Secondly, a multi-messenger platform using velocimetry and in situ angularly and spectrally resolved X-ray scattering is fielded to measure the thermodynamic conditions and ion structure factor of warm dense matter silicon. The observed liquid scattering is used to infer the pressure, density and temperature state without relying on equation of state models. In addition, the measurements are sufficient to distinguish between and rule out some ion screening models. Finally, temporally-resolved optical Thomson scattering is utilised to characterise turbulent plasmas generated at two high-power laser facilities. These platforms aim to understand magnetic-field generation and amplification to reconcile observations in the universe. Perturbative heating effects induced by the Thomson probe are observed on one platform, affecting the inferred conditions and influencing the mechanisms driving magnetic field amplification. The results from these experiments demonstrate the power of Thomson scattering to benchmark theoretical modelling, in particular when used in conjunction with alternate <em>in situ</em> diagnostics.</p>
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spelling oxford-uuid:d948c60f-e8f3-4843-98a6-97e2bb50466f2024-08-19T15:52:10ZDevelopment of advanced diagnostics for high energy density plasmasThesishttp://purl.org/coar/resource_type/c_db06uuid:d948c60f-e8f3-4843-98a6-97e2bb50466fInertial confinement fusionThomson scatteringHigh-density plasmasEnglishHyrax Deposit2024Poole, HGregori, GRegan, S<p>The field of high-energy density physics explores the properties of matter at extreme conditions, crucial for both astrophysical insights and in the pursuit of fusion energy. However, the complexity of competing forces influencing material behaviour within this regime necessitates experimental validation of theoretical models. One powerful experimental technique capable of probing the equation of state is Thomson scattering.</p> <p>This thesis investigates the use of Thomson scattering across diverse experimental setups in the high-energy density regime. Bayesian inference techniques are employed for inferring thermodynamic conditions from experimental observations. Firstly, the feasibility of using Thomson scattering to discern in-flight conditions within inertial confinement fusion implosions is presented. Spatially-integrated synthetic scattering spectra are generated to infer information about the inhomogeneous compressed shell under various adiabat capsule conditions. Secondly, a multi-messenger platform using velocimetry and in situ angularly and spectrally resolved X-ray scattering is fielded to measure the thermodynamic conditions and ion structure factor of warm dense matter silicon. The observed liquid scattering is used to infer the pressure, density and temperature state without relying on equation of state models. In addition, the measurements are sufficient to distinguish between and rule out some ion screening models. Finally, temporally-resolved optical Thomson scattering is utilised to characterise turbulent plasmas generated at two high-power laser facilities. These platforms aim to understand magnetic-field generation and amplification to reconcile observations in the universe. Perturbative heating effects induced by the Thomson probe are observed on one platform, affecting the inferred conditions and influencing the mechanisms driving magnetic field amplification. The results from these experiments demonstrate the power of Thomson scattering to benchmark theoretical modelling, in particular when used in conjunction with alternate <em>in situ</em> diagnostics.</p>
spellingShingle Inertial confinement fusion
Thomson scattering
High-density plasmas
Poole, H
Development of advanced diagnostics for high energy density plasmas
title Development of advanced diagnostics for high energy density plasmas
title_full Development of advanced diagnostics for high energy density plasmas
title_fullStr Development of advanced diagnostics for high energy density plasmas
title_full_unstemmed Development of advanced diagnostics for high energy density plasmas
title_short Development of advanced diagnostics for high energy density plasmas
title_sort development of advanced diagnostics for high energy density plasmas
topic Inertial confinement fusion
Thomson scattering
High-density plasmas
work_keys_str_mv AT pooleh developmentofadvanceddiagnosticsforhighenergydensityplasmas