The search for massive compact halo objects

Abstract

We are develo** a dedicated, semi-automatic system with which we will conduct a definitive search for massive objects (such as brown dwarfs and Jupiters) which plausibly might comprise the dark matter in the halo of the Milky Way galaxy. This search will be conducted by making photometric measurements on up to ten million Magellanic Cloud (or Galactic Bulge) stars, each night for four years, in order to detect the occasional amplification of these stars by the gravitational microlens effect. Simulations have shown that this effect can be used to survey the mass range 10⁻⁷ - 100M _⊙, with sufficient sensitivity to detect ten or more convincing amplification events if objects in this mass range make up the halo dark matter. This means that (i) if these objects make up the halo dark matter, this experiment will detect microlens effects; (ii) if these objects do not comprise the dark matter, this experiment will establish that fact.