Massive stars in the Milky Way: New clues to understand their properties using large spectroscopic samples

Abstract

Massive stars play a crucial role in the chemo-dynamical evolution of the Milky Way, influencing its circumstellar and interstellar medium and being the primary source of heavy-element production. Despite the importance of this stellar population, existing discrepancies between observational data and theoretical models of massive stars have questioned our understanding of these objects. Studying statistically significant and homogeneous volume-limited samples of massive stars is key to alleviating this situation and to narrow down those discrepancies. The IACOB high-resolution spectroscopic database, with almost 3000 sources and a high degree of completeness, allows us to study the physical and chemical properties of our massive neighbors. Key findings from the analysis of ∼ 900 O-type stars and blue supergiants are presented, providing new empirical constraints for new evolutionary model computations.