12:00–1:00 pm Zoom Room
Nicholas Rodd, UC Berkeley, "Evidence the 3.5 keV line is not from dark matter decay"
X-ray observations of nearby clusters and galaxies have reported an unexpected X-ray line around 3.5 keV. This line has received significant attention due to its possible explanation through decaying dark matter, as predicted by, for example, sterile neutrino dark matter. I will present evidence the line does not originate from dark matter decay. In particular, using over 30 Ms of XMM-Newton blank-sky observations, no evidence for the 3.5 keV is found within the ambient halo of the Milky Way. I will outline how these observations result in the strongest limits to-date on the lifetime of dark matter in this mass range, and also mention an ongoing re-analysis of the original 3.5 keV discovery.