Orateur
M.
Stefano Magni
(Université Montpellier 2)
Description
The knowledge of the high velocity tail of the WIMP velocity distribution function has a strong
impact on the way direct detection (DD) may constrain or discover light WIMPs in the GeV
mass range. Recently, there have been important observational efforts to estimate the so-called
Galactic escape speed at the position of the Earth, like for instance the analysis published in early
2014 by the RAVE Collaboration (Piffl et al., 2014), which is of interest in the perspective of
reducing the astrophysical uncertainties in DD. Nevertheless, these new estimates cannot be used
blindly as they rely on assumptions in the dark halo modelling, which induce tight correlations
between the escape speed and other local astrophysical parameters (circular velocity, dark matter
density, distance to the Galactic center). We make a self-consistent study of the implications of
the RAVE results on DD assuming isotropic DM velocity distributions, both Maxwellian and
ergodic. Taking as reference the experimental sensitivities currently achieved by LUX, CRESST2,
and SuperCDMS, we show that the uncertainties inferred for the exclusion curves in the low
WIMP mass region are moderate. We discuss the level of (dis)agreement of these results with
other independent astrophysical constraints.
Auteurs principaux
Dr
Julien Lavalle
(Lab. Univers et Particules de Montpellier (LUPM))
M.
Stefano Magni
(Université Montpellier 2)
