Speaker
Description
The first months of JWST science operations have brought forward multiple AGN candidates in the early universe. Acquiring high quality spectra across such epochs is imperative for constraining how early universe galaxy populations may have existed, and can help explore the nature of their stellar populations, in addition to AGN components if present. Dedicated study of such high-redshift sources yields opportunities to add to this picture, and may additionally contribute to discussions of AGN feedback in early Universe galaxies, as well as metal enrichment during the epoch of reionization.
One instance relating to these endeavours is the study of SMACS S06355, a galaxy at redshift z = 7.66 with potential NeIV emission (Brinchmann (2023)), which cannot be produced by star formation alone. This talk will present a further spectroscopic analysis on this galaxy, through use of spectral analysis and the SED fitting code BEAGLE-AGN (Vidal-García, Plat & Curtis-Lake et al. (2022)), the AGN extension of the code BEAGLE (BayEsian Analysis of GaLaxy sEds; Chevallard & Charlot (2016)). This tool is able to characterise Type II AGN by retrieving physical parameters of the narrow line region.
The application of this to SMACS S06355 therefore allows us to extract information about the galaxy in relation to its AGN based attributes as well as its star formation, in a simultaneous manner. These include both AGN and HII region metallicities, ionisation parameters and SFR. Paired with high-redshift sources, these methods present exciting opportunities to characterise AGN and star-forming components concurrently in some of the most pivotal epochs of the Universe’s lifetime.
