21-cm cosmology topics

by Dr Francisco Villaescusa-Navarro (Center for Computational Astrophysics, Flatiron Institute)

Thursday 15 Feb 2018, 15:00 → 16:00 US/Eastern

small seminar room (BNL)

Hydrogen is the most abundant element of the Universe. Once reionization is completed, a fraction of it remains neutral and emitting radiation with a wavelength of 21 centimeters. That radiation can be detected by radio-telescopes, and through the intensity mapping technique, very large volumes of the Universe can be surveyed very efficiently. The goal of future surveys is to do precision cosmology using that technique. In order to extract the maximum information from those surveys accurate theoretical predictions are needed in the mildly/fully non-linear regime. I will discuss what are the main ingredients we need to model the abundance and clustering properties of cosmic neutral hydrogen, from linear to fully non-linear scales. I will show how we are investigating and calibrating those ingredients using the most advanced cosmological hydrodynamic simulation ever run. I will discuss how we can use neutral hydrogen to weigh neutrinos and to learn about the nature of dark matter, and how well the future Square Kilometer Array (SKA) can constraint them. Finally, I will discuss the prospects of detecting the Baryonic Acoustic Oscillations peak with the SKA and the importance of the design and strategy in radio-surveys.