New Search for Monochromatic Neutrinos from Dark Matter Decay (pdf)

In 2013, the IceCube experiment brought to light the existence of a flux of very high energy neutrinos. The origin of those neutrinos is shown to be extraterrestrial, as they do not fit atmospheric backgrounds at high energy. Still, where those neutrinos are exactly sourced from remains an open question. In the context of dark matter searches, the discovery of a neutrino line would provide a smoking gun for the existence of the dark matter particle. We recently performed a search for such a line, which we propose to review in this talk. Not having found any significant hint for such a signal in the analysed dataset, we derived new bounds on the monochromatic neutrino signal produced from dark matter particle decays. We show a very strong improvement of the limits compared to most recent analyses from the IceCube collaboration. We also discuss how these limits now compare to the ones obtained with gamma lines, the other possible smoking gun for dark matter.