The agent will take part to the ANR-funded VIEWS project (Voyega Into the Engine with the Webb Space telescope). This project aims to explore the interplay between black-hole feeding and AGN-feedback (star formation regulation by Active Galactic Nuclei) mechanisms in the core of massive galaxies. VIEWS leverages the capabilities of the James Webb Space Telescope cycle 3 project GO5018 to provide high-resolution imaging and spectroscopy of six selected Brightest Cluster Galaxies. Two categories of scientific objectives will be addressed. The first one is related to AGN feedback at intermediate scales, to the cooling of the gas and the regulation of star formation around the galaxies: do the cooling filaments fuel star formation ? How is the AGN-feedback energy dissipated and how does it affect star formation and galaxy growth via kpc-scale filaments ? The second category of studied questions relates to the feeding of the black hole and the feedback loop at small scales, focusing on the formation and physical state of circum-nuclear disks: how much gas is accreted in the central disk and available to eventually feed the supermassive black hole compared to the total mass budget of the large scale cooling filaments ? What are the processes of feedback at play in the circum-nuclear region ?

To address these questions, the applicant will combine state-of-the-art emission models for photoionized, photodissociated, and shocked gas (CLOUDY, Meudon PDR, and Paris-Durham codes) to disentangle the relative contributions of radiative and mechanical energy to JWST spectra. Using existing and newly computed model grids, the postdoc will develop an integrated framework to infer excitation conditions and quantify the impact of fast, tenuous shocks on ionized line emission. In parallel, high-resolution 3D MHD simulations of fast shocks interacting with dense interstellar clouds will be carried out with an advanced RAMSES code that includes time-dependent chemistry and radiative cooling. These simulations will self-consistently follow the transfer of mechanical energy, molecular excitation, and resulting emission—providing the first fully coupled view of how shocks shape the multiphase ISM and guiding the interpretation of JWST observations.

The successful candidate will work within the "Astrophysics" team at Laboratoire de Physique de l'École Normale Supérieure (LPENS), an institute that maintains a lively visitor program and hosts regular workshops and conferences throughout the year. The successful candidate will be immersed in an internationally visible research environment in the Paris Campus, with rich intellectual and computational resources.
The appointment is for 2 years with a salary including French social security benefits. Funding will also be allocated for travel.