Speaker
Description
In this contribution, we present a project specifically dedicated to conducting a comprehensive, homogeneous, and precise analysis of the abundances of carbon, nitrogen, and oxygen (CNO) in a large set of stars belonging to all main Galactic stellar populations. We are using the results to investigate the chemical enrichment history of these elements and explore the effects of evolutionary mixing processes on their abundances in stellar atmospheres. These three elements are essential for life as we know it, being part of all the main molecules currently considered biomarkers in exoplanetary atmospheres (e.g., CO2, H2O, CH4, and N2O). Therefore, understanding the origin and history of CNO also has implications for the quest to find life in the Universe.
To achieve our goal, we have started an ambitious analysis strategy based on our previous experience and recent methodological developments. Our sample consists of a combination of spectra from new observations and publicly available data from several stellar surveys. We are using a set of reference stars with accurate stellar parameters to ensure the accuracy of the results obtained from the new spectra. Moreover, the same set of reference stars is used to improve the accuracy of the stellar parameters and the precision of the abundances available from large surveys, following calibration methods that we developed in previous work.
Combining abundances, ages, and stellar orbits, we are performing among other things a stellar population and radial migration analysis to pinpoint the Galactic region of origin of the stars in the sample. In this way, we can investigate for the first time the local details of the CNO enrichment as a function of the Galactic radius in a large volume of the Milky Way. In this contribution we aim to present the main idea and first results of the study.