Rutgers University Astrophysics Seminar
The HI view of the low mass Universe
Dwarf galaxies are important testbeds for galaxy formation and cosmology. With their small sizes and low gravitational potential wells, they are extremely susceptible to feedback and disruption. Discrepancies between observations of dwarf galaxies and results from simulations have been used to test our cosmological model and as motivation to improve the resolution and feedback implementation of simulations. The current era of large, blind neutral hydrogen (HI) surveys hold a lot of promise for studies of dwarf galaxies. HI surveys preferentially select isolated, field galaxies, providing a strong complement to existing in-depth studies of dwarf galaxies near more massive galaxies. Practically, HI observations also offer a measure of the internal kinematics of a source, critical for constraining the dark matter halo and connecting observations to simulations. One key example is the behavior of dwarf galaxies on the baryonic Tully-Fisher relation, which relates their total baryonic mass to their rotational velocity, and I will highlight how two different HI-selected dwarf galaxy populations from the ALFALFA HI survey can test our understanding of this fundamental relation. I will also discuss the exciting future for HI studies of dwarf galaxies with ongoing surveys such as the Apertif imaging surveys and the HI emission component of the MIGHTEE survey.