Speaker
Description
The Fermi Large Area Telescope, with its exceptional sensitivity, has played a crucial role in the indirect search for Weakly Interacting Massive Particles (WIMPs) as dark matter (DM) candidates using gamma rays. However, the domain of dark matter with masses exceeding TeV energies remains less explored. In the case of such heavy dark matter, secondary gamma rays can be produced when high-energy electrons and positrons, resulting from the annihilation or decay of heavy dark matter, lose energy through inverse Compton and synchrotron emissions in the interstellar environment. By searching for these secondary emissions, we can extend the scope of LAT's dark matter search to include more massive dark matter candidates. In this talk, we present recent results on the search for heavy dark matter using 14 years of the Fermi Large Area Telescope (LAT) observations towards nearby dwarf spheroidal galaxies and galaxy clusters. We will show how our extended search strategy has led to stringent constraints on the annihilation and decay of heavy dark matter, which are competitive with those from other high-energy gamma-ray instruments. We also examine a variety of systematic uncertainties associated with the assumptions made in calculating these secondary emissions to demonstrate the robustness of our constraints.
