A new study of oxygen abundances derived from the O I triplet

Despite being the most abundant element in the Galaxy and the fact that the first determinations of its abundance in large samples of stars date back to the 60s, the evolution of oxygen along the Galactic history is still quite puzzling. In short, the results obtained by analyzing different oxygen abundance indicators (the O I triplet, the forbidden [O I] lines, the near-UV and IR OH molecular lines) are discrepant and prevent us from achieving a satisfactory interpretation of the oxygen evolutionary trend (e.g., [O/Fe] vs. [Fe/H]). Here, we present the preliminary results of a new analysis of the O I triplet in a large sample of halo and disk stars.