New Spectral Line of Barium Enhances Stellar Abundance Analysis

Recent research has identified a new near-infrared (near-IR) spectral line of barium, a key s-process element, which could enhance our understanding of stellar populations and their chemical evolution. The study, titled "M giants with IGRINS IV. Identification and characterization of a near-IR line of the s-element Barium," was conducted by G. Nandakumar and colleagues and focuses on the analysis of 37 M giants in the solar neighborhood using the IGRINS spectrometer on the GEMINI South telescope.

The researchers successfully observed the barium line at a wavelength of 23,253.56 Å in the K band, demonstrating its utility for abundance analysis in M giants and cooler K giants with higher metallicities. This spectral line becomes weaker at higher temperatures, limiting its application primarily to these cooler stars. The identification of this line allows for the inclusion of barium in the trends of other heavy elements previously studied, such as copper, zinc, yttrium, cerium, neodymium, and ytterbium.

The implications of this discovery are significant for the study of nucleosynthetic channels, particularly the s-process and r-process, especially in regions obscured by dust, such as the Galactic Center. By expanding the available spectral lines for analysis, this research opens new avenues for understanding the chemical evolution of stars and the dynamics of stellar populations in our galaxy.

For further details, the paper can be accessed at arXiv:2408.12971.