Date of Award
Doctor of Philosophy (PhD)
Electron beam ion traps (EBITs) are small-scale laboratory devices that create and trap highly charged ions (HCI) for spectroscopic studies. These devices create plasma conditions resembling astrophysical environments like stellar winds and supernova remnants, providing valuable insights into astrophysical plasma. Theoretical models for such systems require incorporating relativistic and quantum electrodynamics effects, making experimental studies of HCIs essential for benchmarking these theories.
Spectral analysis of astrophysical and laboratory plasma requires understanding the ionization balance. Accurate atomic data, including excitation, ionization, and recombination cross sections, along with precise knowledge of operating conditions such as electron beam density, electron beam energy, and trapped ion temperature, are essential for simulations. Previous results from the Hitomi mission have highlighted the dominance of systematic uncertainties originating from models and underlying atomic physics over instrumental and statistical uncertainties . As a result, the need for more precise ionization cross-section data has emerged to enhance the modeling accuracy of astrophysical plasma temperatures, with a specific focus on highly charged Fe ions. In the first part of this work, electron-impact ionization cross sections of He-like Fe24+ were measured with the NIST EBIT. In the second part of this work, we aim to contribute more experimental atomic data of the lanthanide element, neodymium (Nd). Those data are expected to be valuable for benchmarking the theoretical model and the development of next-generation EUV lithography sources.
Yang, Yang, "Spectroscopy of Highly Charged Ions for Astrophysical and Laboratory Plasma Diagnostics" (2023). All Dissertations. 3389.
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