The DRIFT Directional Search for Dark Matter with Spin-Dependent Couplings

University Of New Mexico, Albuquerque NM

Investigators

Abstract

In this era of precision cosmology, measurements suggest that ordinary matter represents only a fraction of the total matter density in the Universe. The rest, whose effect we can only see gravitationally, appears to be dark. Particle physics models suggest that dark matter is composed of relic weakly interacting massive particles (WIMPs) left over from the Big Bang. Efforts to directly detect WIMPs are hampered by small interaction probabilities and large backgrounds that mimic expected dark matter signals. Fortunately, a number of unique dark matter signatures exist that can be used to discriminate against backgrounds and decisively identify WIMP interactions. The largest and most robust of these signatures, based on the predicted behavior of the WIMP flux as the Sun-Earth system moves through the galaxy, is a day-night modulation of nuclear recoil directions in the lab frame. The intellectual merit of this proposal resides in the Directional Recoil Identification From Tracks (DRIFT) Experiment's unique and powerful capabilities being brought to bear on one of the most important questions in science today. This award provides funds to support this group and to provide the funds for fiducializing DRIFT and retrofitting the present DRIFT detector in the Boulby (U.K.) Mine with such a system. Broader impacts of this work include the training of students (including under-represented minorities) in increasingly rare small-scale experiments, giving them exposure to a wide range of hardware and software experience. The UNM DRIFT group has demonstrated this capability with previous NSF funding. The DRIFT detector technology has promising applications to axion searches, Homeland Security and double-beta decay experiments.