%0 Journal Article
%T Unique Signature of Dark Matter in Ancient Mica
%A Daniel P. Snowden-Ifft
%A Andrew J. Westphal
%J Physics
%D 1997
%I arXiv
%R 10.1103/PhysRevLett.78.1628
%X Mica can store (for >1 Gy) etchable tracks caused by atoms recoiling from WIMPs. Because a background from fission neutrons will eventually limit this technique, a unique signature for WIMPs in ancient mica is needed. Our motion around the center of the Galaxy causes WIMPs, unlike neutrons, to enter the mica from a preferred direction on the sky. Mica is a directional detector and despite the complex rotations that natural mica crystals make with respect to this WIMP ``wind,'' there is a substantial dependence of etch pit density on present day mica orientation.
%U http://arxiv.org/abs/astro-ph/9701215v1