Pre-submission Thesis Presentation

Galaxies are the building blocks of our universe. The way they evolve is still being debated. The galaxies consist of three components: a galactic disc, a dark matter halo, and a diffuse gaseous halo, known as the Circumgalactic medium (CGM), surrounding galactic disks. It is now apparent that the CGM plays a crucial part in galaxy evolution. The CGM is the habitat for large-scale gas flows that fundamentally regulate the evolution of the galaxy by providing fresh and recycled gaseous fuel for star formation and regulating the galaxy's interactions with other galaxies. Using theoretical models, simulations, and observations, we investigated the detailed structure (first part of my talk) and interactions (second part of my talk) of the CGM. 

In the first part of my talk, I will discuss our investigation of the crucial role of photoionization and temperature fluctuations on the highly ionized oxygen ions in the CGM of galaxies of varying masses. In this part, I will also discuss how OVIII column density, gamma-ray, and radio background observations help us constrain the cosmic ray population in the CGM; one of the big mysteries in CGM studies. In the next part, I will highlight two interactions of CGM gas with two different components: one with cosmic rays and another with satellite galaxies in light of idealized simulations. By exploring these interactions and structures of the CGM, we connect the dots and better understand how galaxies evolve.