Understanding Multi-Wavelength Signatures of Galactic Outflows Through 3-D Simulations

Abstract

Evolution of galaxies is a phenomenon that affects the formation and composition of galaxies, and the intergalactic medium. It is mediated by processes that establish a symbiotic relationship between a galaxy and the surrounding circum-galactic medium (CGM) by enabling the exchange of mass, momentum, energy, and metals between the two. For star-forming galaxies, one side of the exchange is driven by galactic outflows (GOs) emerging from supernovae explosions (SNes). GOs posses a complex, multiphase structure which covers several orders in magnitudes of density and temperature. A complete description of GOs should be able to capture all its characteristics and replicate its multi-wavelength observations. Due to its complicated phase structure, analytical modelling of GOs is limited in scope and therefore, significant effort in this field is devoted to the simulations of these outflows. In this thesis, we use idealised simulations of isolated galaxies to understand GOs from star-forming Milky Way (MW) -type galaxies. We consider the evolution of the outflowing gas over several Myr and focus on the properties of the extraplanar gas. We produce synthetic observations which we compare with existing X-ray and radio observations. By conducting simulations with various star formation rates, we connect the properties of the extraplanar gas with the underlying star formation occurring in the disc. We study the different thermal phases and their kinematical and dynamical properties in GOs as they travel through the CGM. To quantify the interactions taking place between the different phases, we analyse simulations of a local patch of the solar neighbourhood.