Abstract
We investigate the sensitivity of the Gamma-ray Large Area Space Telescope(GLAST) to indirectly detect weakly interacting massive particles (WIMPs)through the $\gamma$-ray signal that their pair annihilation produces. WIMPsare among the favorite candidates to explain the compelling evidence that about80% of the mass in the Universe is non-baryonic dark matter (DM). They areserendipitously motivated by various extensions of the standard model ofparticle physics such as Supersymmetry and Universal Extra Dimensions (UED).With its unprecedented sensitivity and its very large energy range (20 MeV tomore than 300 GeV) the main instrument on board the GLAST satellite, the LargeArea Telescope (LAT), will open a new window of discovery. As our estimatesshow, the LAT will be able to detect an indirect DM signature for a large classof WIMP models given a cuspy profile for the DM distribution. Using the currentstate of the art Monte Carlo and event reconstruction software developed withinthe LAT collaboration, we present preliminary sensitivity studies for severalpossible sources inside and outside the Galaxy. We also discuss the potentialof the LAT to detect UED via the electron/positron channel. Diffuse backgroundmodeling and other background issues that will be important in setting limitsor seeing a signal are presented.