Dimming Starlight with Dark Compact Objects

Abstract

We demonstrate a new technique to search for dark compact objects. When dark matter comprising a dark compact object interacts with photons, the compact object can disperse light traveling though it. As these objects pass between Earth and a distant star, they act as "lampshades" that dim the star. We examine how dimming effects from clumps of dark matter in the Galaxy could be searched for in microlensing surveys, which measure the brightness of stars as a function of time. Using the EROS-2 and OGLE surveys, we show that a dimming analysis of existing data can be used to constrain dark sectors, and could be used to discover dark matter in compact objects.

9 pages main text (4 figures), 4 pages appendix (4 figures). Version accepted to PRL