Rafael Zavala Molina   (Mexico)

 rafael.zavala @ uni-heidelberg.de

Modeling the the multi-phase gas dynamics of the CGM three-phase, multi-fluid sub-grid model

While cosmological simulations have been successful in reproducing many aspects of galaxy formation, galaxy evolution remains an open and challenging problem. In particular, one of the most persistent difficulties lies in resolving the circumgalactic medium (CGM), whose multi-scale, multi-phase structure plays a crucial role in regulating gas inflows and outflows around galaxies. Observations reveal the coexistence of cold and warm gas phases embedded within hot galactic halos, often confined to cloud structures with characteristic sizes of only tens of parsecs. However, such clouds are expected to be rapidly destroyed by hydrodynamic instabilities and mixing with the surrounding hot medium.

Current cosmological simulations struggle to account for the survival of these structures due to limited spatial resolution and incomplete treatments of gas microphysics and multi-phase dynamics.

Our aim is to develop a three-phase, multi-fluid sub-grid model to study the multi-phase gas dynamics of the CGM. The model will rely on analytical considerations and validated through tests in idealized setups designed to capture the coupling between the cold, warm, and hot gas phases. We will then apply the model to increasingly complex environments, such as isolated disk galaxies. Ultimately, the model will be used to investigate realistic galactic environments and to provide new insights into the physical processes governing galaxy evolution.

Supervisor:    Max Gronke   (ARI)