Fully theoretical stellar populations: tailoring models for new and future observing facilities

Abstract

Stellar population synthesis models are invaluable to modern Extragalactic Astrophysics. They provide means to extract stellar masses, star formation histories, chemical enrichment histories and dust content of galaxies from their integrated spectral energy distributions, colours or spectra. These models have been evolving through decades. On the one hand, this happens as a natural consequence of a growing understanding of stellar evolution, chemical evolution and model atmospheres. On the other hand, the rapid technological developments in observation facilities press for the development of models able to exploit new data.The collaboration between the host and the visitor has pioneered the development of fully theoretical models of simple stellar populations with alpha-enhancement (Coelho et al. 2007). These models covered a somewhat limited range of galaxy parameters and were restricted to the visible range of the spectra. The availability of better ingredients and the rapid development of observing facilities prompt us to compile a new version of our models tailored to new and future instruments.We aim to compute a library of simple stellar population models using the code GALAXEV (Bruzual & Charlot 2003), an updated version of the spectral stellar library in Coelho (2014), and the knowledge gathered in recent collaborations (Rodriguez-Merino et al 2020, Coelho et al. 2020). The new models will span ages from 30 Myr to 14 Gyr, metallicities from Z = 0.0001 to 0.024 and two alpha-enhancements ([alpha/Fe] = 0.0 and 0.4).The models will cover from 100 nm to 3 micron at various spectral resolutions. The goal is to cover from the high-spectral resolution that MOSAIC will need to the photometric bands already in place in James Web ST, passing by the quasi-spectral regime of J-PAS. A large fraction of the ingredients needed have been assembled through remote interactions between the host and the visitor, and we expect to have a draft of the work ready by the end of the visit. Moreover, in parallel to the research activities, discussion activities will be offered to the students of the Astronomy graduate program. Such activities will allow the students to learn methods and concepts about this important field in Extragalactic Astrophysics. (AU)