Line Ratio in the C-like Ion Spectrum O III: Testing Atomic Theory Predictions Through the Observation of Galaxies

The progress made in atomic structure computations has indicated that certain line ratios of forbidden transitions may be slightly different from earlier assumptions. In order to check this theory, we evaluate previous observations of dwarf galaxies by the UVES spectrograph at the VLT telescope on ESO Paranal for the line ratios of branched decays in C-like oxygen ions [O III] that are insensitive to the local environment. Our findings show that the observed line ratio for [O III] (r=3.005±0.237) aligns with recent theoretical predictions based on more sophisticated models, while it deviates from older computations. Additionally, the analysis of line profiles suggests that, in some cases, the spectral resolution was insufficient to fully resolve dynamic substructures within the galaxies. Our results emphasize the importance of improved data quality and consistency for future studies, especially for future searches of finestructure constant variations at higher redshifts using this method.