Special Astrophysics Seminar

Mapping the Baryonic Universe: From Reionization to Present-Day Galaxies

Hamsa Padmanabhan

CITA

The history of the baryonic (normal) matter in the universe is an excellent probe of the formation of cosmic structures and the evolution of galaxies. Over the last decade, considerable effort has gone into investigating the physics of baryonic material, particularly after the epoch of Cosmic Dawn: signalling the birth of the earliest stars and galaxies --- widely considered the ‘final frontier’ of observational cosmology today. The technique of (line) ‘intensity mapping’ (IM) has emerged as a powerful tool to explore this phase of the universe by measuring the integrated emission from sources over a broad range of frequencies. I will overview my current research on the mapping of atomic hydrogen over 12 billion years of cosmic time, based on a data-driven framework developed for interpreting current and future IM observations. I will then describe extensions of this approach which provide a comprehensive picture of molecular gas evolution, and interpret results from ongoing observations. This opens up the exciting potential of constraining fundamental physics from Cosmic Dawn.