- June 26, 2017, 2:00 pm US/Central
- Thomas Lacroix, University of Montpellier / CNRS
Indirect detection techniques are a very promising avenue to look for dark matter (DM) particles by exploiting astrophysical observations. This is especially interesting when studying the centers of galaxies, where DM over-densities are expected. Moreover, DM particles may be significantly clustered in galactic cores around supermassive black holes, forming density spikes.
I will present several original ways to study the inner DM profile in two neighboring galaxies, M87 and Centaurus A, where the case for DM spikes is fairly strong. I will discuss the constraints on the DM annihilation cross section obtained by studying the spectral energy distribution of M87’s core. Then I will show that one can go a step further by using the ground-breaking Event Horizon Telescope to probe the
spatial morphology of the DM-induced synchrotron signal in the very inner region of M87, in the millimeter band. Finally, I will move on to higher energies and discuss the implications for DM of the hardening we reported in the Fermi-LAT gamma-ray spectrum of Centaurus A’s core.