Measuring Dark Matter Distribution in Directional Direct Detection

Direct detection of dark matter with directional sensitivity offers not only measurement of both recoil energy and direction of dark matter, but also a way to understand dark matter distribution in the Galaxy. Maxwell distribution is usually supposed as the distribution near the Earth, however, deviation from that, caused by tidal streams in the Galaxy, has been suggested. We explore the possibility of distinguishing the distribution by direct detection using nuclear emulsions.