Daniel Santos (LPSC) "Directional Direct Dark Matter Detection and Neutrino Spectroscopy with MIMAC"

The hypothesis of the existence of non-baryonic dark matter in our galactic halo is supported by all astrophysical observations performed from cosmological to local scales. The measurement of one clear experimental signal of this matter represents one of the most important challenges for physics today. The direct detection of an elastic collision with a target nucleus of a weakly interacting massive particle (WIMP), the most accepted candidate for such a matter, has to be discriminated from those produced by neutrons and neutrinos, which produce the same expected signal. The only non-ambiguous signature to be able to discriminate the WIMP events from neutrons-induced events is to correlate these elastic collisions in the detector with the relative motion of our Solar system with respect to the galactic halo. The measurement of thedirection of the nuclear recoil track in 3D of a few tens of keV is called “directional detection”. The directional detection opens a new field in cosmology: it brings the possibility to build a map of nuclear recoils exploring the galactic halo and gives access to a particle characterization of dark matter. The MIMAC (MIcro-tpc MAtrix of Chambers) collaboration has developed in the last years an original prototype detector based on the direct coupling of a pixelized Micromegas with a special developed fast self-triggered electronics showing the feasibility of a new generation of directional detectors. The flexibility of the MIMAC detector to change the nucleus target, changing its mass and spin, makes possible to adapt the search of candidates proposed by the large mass direct detection projects as LUX, Xenon1T, SCDMS or Edelweiss. In the next years, these large mass detectors will either detect some candidates or the neutrino background floor will limit them. In both cases a directional detector will be needed to confirm the galactic halo origin of such candidates or to go further the neutrino background. The MIMAC angular resolution measured coupling one of the chambers with COMIMAC, a dedicated facility developed allowing ionization quenching factor measurements and electron calibration, will be shown. The localization of the 3D track by the cathode signal will be described and the new possibilities open by this new directional detector in the neutron spectroscopy will be illustrated.