This Is AuburnElectronic Theses and Dissertations

On the study of atomic and molecular processes affecting Astrophysical Plasma using high-resolution optical and UV spectroscopy

Date

2019-06-13

Author

Nemer, Ahmad

Type of Degree

PhD Dissertation

Department

Physics

Abstract

Rydberg Enhanced Recombination (RER), a recombination process related to dielectronic recombination in which electrons are captured into energy states below the ionization threshold, has been theoretically predicted to occur in low temperature plasmas. First evidence of RER is shown to occur in astrophysical environments, using high resolution optical spectra of planetary nebulae and a UV spectrum of symbiotic stars. RER can significantly impact diagnosed ionic and elemental abundances of important astrophysical species, with implications for cosmological models. The project underlines the importance of including this process in models of photoionized plasmas. ii