Joint Astrophysical Colloquium
The spatially resolved properties of the ISM in galaxies during the Epoch of Reionization
Livia Vallini (INAF-OAS)
Thursday 07/12/2023 @ 14:00, Sala Antonio Sollima (IV piano Battiferro) + remoto
The Epoch of Reionization (EoR) represents a critical phase of the Universe during which the first galaxies started to rapidly form stars eventually ionizing the surrounding IGM. For this reason, shedding light on how the gas is converted into stars, and how this process is influenced by the interstellar medium (ISM) properties and by the possible feedback from AGN holds the key to shed light on the reionization process. In this talk I will present a new physically motivated model that, taking spatially resolved [OIII], [CII] and dust continuum emission as inputs, allows us to derive the gas density, the gas-phase metallicity, and the deviation from the Kennicutt-Schmidt relation over sub-kpc scales in the ISM of high-z sources. I will discuss the application of our method on UV luminous Lyman Break Galaxies and perspectives for including the effect of X-rays from low-luminosity AGN. Our analysis suggests that high [OIII]/[CII] ratios are produced by ongoing starbursts that bring the galaxies above the Kennicutt-Schmidt relation especially in the central regions. This translates into gas depletion times in the range t_dep=80-250 Myr that anticorrelate with the dust temperature.