Work on dark matter experiment begins at Sanford Underground Lab

By Journal staff

As the water level at the Sanford Underground Laboratory at Homestake in Lead reached 5,027 feet, crews have begun to prepare to install the first physics experiment at the 4,850-foot level.

Sanford Lab crews are driving a tunnel to the Davis Cavern on the 4,850-foot level of the lab. That cavern, excavated in 1965, is where nuclear chemist Dr. Ray Davis installed an experiment to measure subatomic particles called neutrinos produced by the sun.

Now, the cavern is being prepared for an experiment that will search for an elusive, never-detected substance called "dark matter." The Large Underground Xenon detector, or LUX, will use 350 kilograms of liquid xenon in a cryostat that will be placed inside a sleeve of water in the Davis Cavern. Experiments to detect and measure neutrinos, dark matter and other subatomic phenomena are installed deep underground to shield them from background cosmic radiation.

Sanford Lab personnel and contractors also have remodeled a former Homestake warehouse as a LUX surface lab, complete with clean room, where scientists will assemble and test the LUX detector before sending it underground in 2010.

Lab officials say the first-ever detection of dark matter will be a major step toward better understanding the fundamental nature of the universe.