Constrasting Simulations and Observations: What can we learn about galaxy evolution with JWST and ELT-HARMONI

Cosmological simulations have now reached a level of maturity where the size scales that they can probe at Cosmic Noon (peak of the epoch of star formation, at redshifts between 2 and 3) now matches the spatial resolution achieved by state-of-the-art observing facilities such as ELT and ALMA. Thus, for the first time, we are in a position to make predictions (based on simulated galaxies) as to the physical conditions within galaxies at cosmic noon, in a spatially resolved manner, and compare & contrast these predictions with constraints from near-infrared and sub-mm observations.

Active Galactic Nuclei (AGN) form an important component of galaxies at these epochs, and their energy output (so called AGN feedback) has strong consequences for star formation and the evolution of their host galaxies. This thesis project will invoke new computational methods to include the radiative impact of the AGN on the gas and dust within the host galaxy, thus providing us with the ability to accurately predict the fluxes, kinematics and dynamics of a number of emission and absorption features.

Observationally, these features can constrain the physical conditions of the gas and dust within these galaxies, such as temperature, density, ionization state, chemical composition, and line-of-sight extinction. The comparison of observations with the simulations can then be used to hone our understanding of the physics that underpins galaxy evolution over cosmic time.

JWST is a unique observatory that has incredible sensitivity over the entire near-infrared and mid-infrared wavelength range. By analysing JWST integral field spectroscopic observations of nearby galaxies, we can bracket the range of parameter space that is occupied by gas and dust in different regions of the galaxy, such as galaxy scale outflows, the ionization cones (narrow line regions) of AGN, the galaxy's disk, and star-forming regions within it.

These regions include those impacted by the presence of the AGN, and those that are not affected by it. The JWST data will be vital to ensure that the simulations are compatible with observations in terms of the range of physical parameters within each region. Thus, they can be used to improve the robustness and physical accuracy of the models that form a core component of the thesis work.

Once the models are mature, we will use them to inform future observing programmes with the ELT instrument HARMONI, where we plan to use the combination of superb sensitivity and exquisite spatial resolution to probe conditions within galaxies and cosmic noon, and through comparison with simulations, predict the evolution of these objects over cosmic time.