Voyager probing Dark Matter
- Mr. Mathieu BOUDAUD
- Mr. Mathieu BOUDAUD (LPTHE, Paris, France)
We take advantage of spacecraft Voyager 1's capacity for detecting interstellar CRs since it crossed the heliopause in 2012. This opens up a new avenue to probe DM through CR electrons and positrons in the sub-GeV energy range. From a complete description of the transport of electrons and positrons at low energy, we derive predictions for both the secondary astrophysical background and the pair production mechanisms relevant to DM annihilation or decay down to the MeV mass range. We combine the constraints from the Voyager and AMS-02 data to get novel limits covering a very extended DM particle mass range, from MeV to TeV. For p-wave annihilation, we make use of the Eddington method to compute the velocity average annihilation cross section from the most recent constrained mass model of the Galaxy. Primordial black holes are also motivated candidates for dark matter. Black holes with a mass smaller than ~10^17 g are expected to inject electrons and positrons in the Galaxy through Hawking radiation. We derive novel constraints on the contribution of primordial black holes to dark matter in this mass window. Though extracted from a completely different and new probe, these bounds have a strength similar to those obtained with the extragalactic gamma ray background.