Michaela Hirschmann - A modern theoretical framework for the cosmic evolution of galactic nebular emission lines

A modern theoretical framework for the cosmic evolution of galactic nebular emission lines

by Michaela Hirschmann (Ecole Polytechnique Federale de Lausanne & INAF - Trieste)

Abstract: Optical and UV emission lines in observed galaxy spectra provide important diagnostics for the interstellar medium and their excitation sources in galaxies. After an introductive review of the current state of the art in the theory of nebular emission lines of galaxies, a novel method will be presented to model the luminosities of optical and UV emission lines of simulated galaxies over cosmic time. The lines originate from the exposure of chemical elements in the galactic interstellar medium to the radiation field from accreting supermassive black holes and massive stars, and can be used to trace the physical conditions for star formation and supermassive black hole growth. In the case of UV lines, this analysis can be pushed to the earliest cosmic epochs, probing the extreme conditions of the interstellar medium and radiation fields expected in primeval galaxies. We demonstrate how such an approach can be combined with the performances of new-generation observing facilities over the next decade, such as JWST, to design novel high-redshift observational programs able to prove or disprove current theoretical models.

Contact: G. De Lucia