DMTPC: a direction-sensitive dark matter search

A WIMP detector with directional sensitivity could correlate signal events with astrophysical sources, thereby providing a definitive observable signature of dark matter. Our Dark Matter Time-Projection Chamber (DMTPC) collaboration uses a gas-based detector with optical and charge readout to achieve directional sensitivity. We have built a 10 liter prototype detector and operated it in a surface laboratory. The detector consists of two back-to-back time-projection chambers enclosed within a vacuum vessel which is filled with CF$_4$ gas at 75 Torr. I will report on the results from this run, including the first DMTPC limit on the spin-dependent cross section. In addition, I will describe our next-generation detector which we will deploy underground at the WIPP facility in New Mexico (1.6 km water equivalent depth).