Presentation
Stellar spectroscopy allows us to determine the properties and chemical compositions of stars. From this information for stars of different ages in the Milky Way, it is possible to reconstruct the chemical evolution of the Galaxy, as well as the origin of the elements heavier than boron, created mainly in stellar interiors. It is also possible to study stellar formation, and the formation of the Galaxy, from the signature of the Galactic potential on the stellar orbits, and the distributions of mass, ages, and the abundance of heavy elements.
Obtaining high-resolution spectra, as necessary for studies of chemical compositions, requires advanced and efficient instrumentation. This is particularly true for research that calls for large stellar samples, which demands the observation of hundreds or thousands of sources simultaneously. Efficiency requires that the data processing and analysis
are performed in an automated way. The interpretation of spectra is based on physical models of the atmospheres of the stars, from where the light that we observe escapes the stars. The main ingredients for building such models are the fluid
dynamics, and the properties of the atoms, ions, and molecules, especially regarding their interactions with the radiation coming from the stellar interior. Once we have a plausible model, it is possible to compute in detail how the radiation propagates through the stellar atmosphere, and the emergent spectrum, which can then be iteratively compared with the observations to refine the model. This project covers three different research fronts:
- Improving model atmospheres and simulations of stellar spectra.
- Developing tools for data reduction and the analysis of spectroscopic observations, in particular for the determination of chemical abundances in stars. This includes software, computing and instrumentation (e.g. HORUS)
- Designing, preparing, and executing spectroscopic studies of stars aimed at understanding
- the most relevant aspects of the physics of stellar atmospheres,
- the formation and evolution of stars,
- the origin of the chemical elements, and the formation, structure, and
evolution of the Milky Way galaxy.