Dr. Kartick Sarkar

Energy produced by supernovae or supermassive black holes play a major role in dictating the evolution of galaxies. The produced energy is directly responsible for heating the star-forming gas in the interstellar medium or stopping the gas to reach the galaxy, thus suppressing overall star formation. The interaction between the produced energy and the interstellar medium is often mediated by bubbles and winds. In this talk, I will discuss how observations of supernovae remnants and winds are affected by non-equilibrium ionization and dynamically changing radiation fields. I will show that in such fast-evolving systems, the normal assumption about equilibrium ionization leads to significantly different observational outcomes. I will further discuss a set of superbubbles in our Galaxy, known as the Fermi/eROSITA bubbles. These bubbles are observed to have sizes of 8-12 kpc and are visible in radio, X-ray, and gamma rays. I will finally discuss my theoretical models to constrain the origin of these bubbles.