The density-velocity structure of Milky Way dark matter – Implications for DM detection experiments
Subha Majumdar (TIFR)
July 18, 2016
Abstract: Properties of dark matter (DM), determined through direct and indirect detection experiments, depend on synergies between astrophysics and particle physics. For example, the density and velocity distribution function of the dark matter in our neighborhood is crucial in determining the collision rates in DM direct detection experiments. Unfortunately, there is a wide dispersion of observationally determined DM density (and profiles); moreover, the ‘standard halo model (SHO)’, unfavored by observations and simulations, is predominantly used by the particle physics community. Using some of the latest compilation of rotation curve data, we make the first ever observational estimate of the DM phase-space of the Milky Way halo up to 200 Kpc (i.e almost r200). Our results bring out deviations from the SHO as well as differences from numerical simulation predictions, and points to the importance of precise determination of visible matter density and the local standard of rest. Finally, we make some comments on the prospects of improving our current knowledge of Milky Way DM using data from GAIA, and a future mission called THEIA.