Tue, Sep 27, 2016, 4:00 pm to 5:30 pm
Dark matter with MeV-to-GeV masses is a theoretically and phenomenologically interesting possibility. In this talk, I will describe how direct-detection experiments can probe this largely unexplored mass range. A particularly promising possibility is that dark matter scatters off electrons, causing ionization or excitation of atoms in a detector target material, which can lead to events containing one or more electrons or photons. I will review how existing XENON10 data probes dark matter with masses as low as a few MeV, and present an improved constraint using recent XENON100 data. After reviewing the challenges for xenon-based experiments to make further progress, I will discuss how experiments with different materials could significantly improve the sensitivity. This includes upcoming experiments using semiconductors (e.g. SuperCDMS, DAMIC) as well as new dedicated experiments using scintillators and other materials. I will focus on ideas that could be realized within the next five years, but also mention other efforts. I will also present a few simple sub-GeV dark matter models, which provide concrete experimental targets, and contrast direct-detection probes with searches at colliders and fixed-target experiments.