Jeu. 02/03/2017 14:00 Grande Ourse, Bâtiment 13, Etage 1
POULIN Vivian (LAPTh Annecy) Constraining Dark Matter decay with Cosmology
(LUPM/Interactions fondamentales, Astroparticules et Cosmologie)
Although the existence of Dark Matter (DM) is by now well-established thanks to a variety of observations on many different scales, its nature is still unknown and so are many of its most basics properties, such as its lifetime. Moreover, even if obvious arguments require that most of the DM is stable on timescales of (at least) the lifetime of the universe, a fraction of it could be in the form of unstable exotic particles that are free to decay at much shorter times. In the literature, numerous relics from the early universe have been proposed in many extensions of the standard model of particle physics, in some cases unstable to processes injecting electromagnetic (e.m.) forms of energy (e.g. ‘superWIMP’, R-parity breaking SUSY models, Sterile neutrinos, Primordial black holes …), but also non-e.m. ones (e.g. the Majoron scenario). In this talk, I would like to review how CMB temperature and polarization anisotropies can be used as powerful probes of the abundance of such electromagnetically *and non-electromagnetically* decaying exotic particles, depending on their lifetime. I will then emphasize the synergy with CMB spectral distortions and Big Bang Nucleosynthesis studies when e.m. channels are switched on, and illustrate how the 21cm signal, one of the main target of future experiments, could be used in order to improve (but not always) over current sensitivity.
Pour plus d'informations, merci de contacter Lavalle J.