Laverick, Michael

PhD thesis supervised by Lobel, A.; Van Winckel, H. (KU Leuven)

Abstract: Accurate atomic transition data are crucial input parameters for the modelling of stars. The fundamental atomic data, such as oscillator strengths and rest wavelengths, governs our very understanding and interpretation of the internal structures, atmospheres, and evolution of stars and stellar environments. As such, any errors and uncertainties in the adopted atomic data run the risk of systematically propagating throughout the entire field of astronomy. Reproducing stellar environments in the laboratory is an exceptionally difficult task, and substantial work is required to obtain large quantities of accurate atomic transition and collisional data. Theoretical calculations of atomic transitions are often required to supplement the missing experimental data, however such calculations can be susceptible to systematic errors and simplifications. A small number of databases offer compilations of such experimental and theoretical atomic data, often containing data that are complementary to one another. Unfortunately despite the tremendous ongoing efforts of atomic data producers and atomic data providers very little information is available on the accuracy of the data, complicating the interpretation of results for astrophysics and other disciplines. The PhD thesis forms an important part of the "Belgian Repository of fundamental Atomic data and Stellar Spectra" project (the BRASS project) which seeks to take the first crucial steps towards removing systematic errors in the input atomic data required for quantitative stellar spectroscopy. The main science goal of the PhD, and of the BRASS project, is to provide accurate and quality-assessed atomic transitions to the community via a new online repository. In addition to the atomic data, we shall also provide many stellar spectra, of high-resolution and high signal-noise ratio, to the community. The atomic data and stellar spectra will be presented together interactively via the repository alongside all assessment results and meta-data associated with both the spectra and transitions. The repository promises to be an important reference for stellar spectroscopy for years to come, providing thorough, extensive, and high-quality work in a clear and accessible manner to the community.

Keyword(s): Stellar quantitative spectroscopy ; Atomic databases ; Stellar atmospheres ; Radiative transfer
Note: Atomic data and stellar spectra of the PhD thesis are online available at http://brass.sdf.org/
ISBN: LIRIAS2820621
Links: link; link2
Funding: BR/143/A2/BRASS