Astrophysics Seminar
On the interplay between galaxies and their dark matter haloes
Speaker: Dr. Jonathan Freundlich (Observatoire astronomique de Strasbourg, France)
In the LCDM model, the formation and evolution of galaxies are inextricably linked to their surrounding dark matter haloes. However, baryonic processes within galaxies can in turn affect the dark matter distribution, notably through different feedback processes driven by stellar evolution and active galactic nuclei. I will review observational and theoretical tensions pertaining to the interplay between galaxies and their dark matter haloes, with the goal to leverage these challenges to either refine our understanding of baryonic processes within LCDM or guide the exploration of alternative models.
On one side, observations concurrently reveal strikingly tight correlations between baryonic and dark matter masses, yet show a diversity in observed rotation curves at any given mass. On the other side, state-of-the-art cosmological simulations do not agree on the effect of feedback processes on dark matter haloes and are thus unable to reproduce the full spectrum of the observed diversity. Observational constraints on the evolution of the dark matter distribution and the scaling relations between baryonic and dark matter masses across cosmic time would help address these challenges, for example with the upcoming Square Kilometer Array.