Directional detection of Galactic Dark Matter is a promising search strategy
for discriminating genuine WIMP events from background ones. Technical progress
on gaseous detectors and read-outs has permitted the design and construction of
competitive experiments. However, to take full advantage of this powerful
detection method, one need to be able to extract information from an observed
recoil map to identify a WIMP signal. We present a comprehensive formalism,
using a map-based likelihood method allowing to recover the main incoming
direction of the signal and its significance, thus proving its galactic origin.
This is a blind analysis intended to be used on any directional data.
Constraints are deduced in the (σn,mχ) plane and systematic
studies are presented in order to show that, using this analysis tool,
unambiguous dark matter detection can be achieved on a large range of exposures
and background levels.Comment: 20 pages, 5 figures Final version to appear in Phys. Lett.