| Contemporary cosmological observations strongly suggest the presence of weakly interacting massive particles (WIMPs) which have not been directly detected to date. In this paper, I discuss the cosmological evidence which suggests the presence of WIMPs, and the justification for believing the cosmological models built around this evidence are sound. I will then discuss the expected WIMP-nucleon interaction rate, and methods of directly detecting these interactions, emphasizing liquid xenon two phase time projection chambers. Two of these liquid xenon time projection chambers will be discussed in detail, from design philosophies, construction, operation, and results to date. Finally, a novel method of calibrating large liquid xenon detectors with 83 mKr will be discussed. Calibration with a 83 mKr source allows for low energy electronic recoils in the fiducial region of the detector, a calibration need which traditional external sources cannot meet. The development of the 83 mKr source for use in a low-background dark matter detector is discussed. |
