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Atomic structure and collisional data for elements applicable to magnetically confined fusion plasmas and neutron star mergers Niall Edward McElroy (23656441) PUREID: 678296778 Atomic structure electron-impact excitation dielectronic recombination In this thesis, we develop relativistic and semi-relativistic atomic structures for a number of important systems. They include singly ionised argon (Ar II), six times ionised tungsten (W VII), as well as compatible pairs of structures for neutral through triply ionised (II, I), (III, II), (IV, III) Tellurium Te, Strontium Sr, Yttrium Y and Zirconium Zr. The Ar and W structures are incorporated into collisional electron-impact scattering calculations, with subsequent collisional radiative modelling to investigate further the influx of impurities into magnetically confined fusion plasmas. The structures for Te, Sr, Zr and Y were used to calculate recombination rate coefficients using the Independent Processes and Isolated Resonances approximation. These resultant rates provide atomic data required for accurate NLTE modelling of astrophysical plasmas. Of particular interest are those plasmas formed during binary neutron star mergers, from which these elements are partially believed to originate. To study the atomic structures of these elements, two multiconfigurational atomic structure codes, namely AUTOSTRUCTURE and GRASP0 were utilised. For the electron-impact excitation collisional work, the Dirac R-matrix (relativistic) and Breit-Pauli BP (semi relativistic) R-matrix codes were used. We also discuss minor performance improvements that were implemented in the GPU version of the common outer-region code of these two scattering suites. Based on collisional-radiative models developed from calculations in this thesis, we present potential diagnostic line ratios of interest. 2026-10-01T16:15:23Z Text Thesis 10.17034/32805524.v1 https://figshare.com/articles/thesis/Atomic_structure_and_collisional_data_for_elements_applicable_to_magnetically_confined_fusion_plasmas_and_neutron_star_mergers/32805524 All Rights Reserved