World's Most Sensitive Dark Matter Detector Gets a Boost

Scientists assemble the LUX dark matter detector. (Credit: Matthew Kapust/Sanford Underground Research Facility) One truism for me that I suspect holds some tiny bit of general truth for many across the broad, beautiful swath of humanity is that the longer I live the more history compresses. Today the work Brahe, Kepler and Galileo did to understand the geometry of the solar system doesn’t seem as distant to me as the scenes from Happy Days did shortly after we landed on the moon. When I teach astronomy and physics I circle back to certain ideas repeatedly. One of these ideas is related to the evolving sense of the flow of time, wherever it may slip. This concept centers on my need to get students to come to terms with the notion that the ideas in their textbooks got there as a result of real struggles by real people. As clear and obvious as the textbook physics may appear, it almost assuredly was a dirty mess at the time. I am reminded of these things by the latest reports from the LUX dark matter experiment that’s looking for evidence of the Weakly Interacting Massive Particles (WIMPs), which are likely to constitute the dark matter filling the universe. The LUX detector consists of 815 pounds of liquid xenon located about a mile underground in the former Homestake gold mine in South Dakota. The mine was the place where Ray Davis conducted the earliest solar neutrino experiments, experiments that led to his Nobel Prize in 2002. When a particle hits the xenon a flash of “scintillation” light is produced as well as electrons from ionized xenon. These electrons are “drifted” to a region where more light is produced.