Large Underground Xenon (LUX) dark matter detector

The LUX dark matter detector seen here suspended in its protective water tank, before water is added.

In July 2012, a team of scientists, engineers and technicians spent two days moving a titanium vessel the size of a phone booth from a surface laboratory at the Sanford Undergeround Research Facility to a cavern nearly a mile beneath the surface of the Black Hills of South Dakota. This one-of-a-kind cylindrical container—nicknamed "the can" by its inventors—is a sophisticated vacuum thermos designed to hold ultra-pure liquid xenon, cooled to a minus 160 degrees F. The liquid xenon will bathe an array of photosensors, each capable of sensing a single photon of light.

The "can" is the core component of the Large Underground Xenon detector, or LUX, which, when fully operational, could become the most sensitive experiment yet to search for the elusive substance called dark matter.

LUX has been installed in the Davis Campus at the 4,850-foot level of the Sanford Underground Research Facility. The great depth of the Davis Campus will shield the LUX detector from the noise of cosmic radiation found on the surface of the earth. The LUX detector also has been installed in a 71,600-gallon tank of pure, deionized water, that will further protect the experiment from extraneous "noise," such as naturally occurring radiation from the surrounding rock.

In this ultra-quiet environment, LUX will search for dark matter particles dubbed "weakly interacting massive particles," or WIMPs. Thought to comprise more than 80 percent of the matter in the universe, WIMPs so far have never been directly detected. The LUX experiment could be taking data by early 2013.

The LUX international collaboration includes 17 universities and laboratories. They are:

  • Brown University
  • Case Western Reserve University
  • The University of Rochester
  • Imperial College London
  • Edinburgh University
  • Lawrence Livermore National Laboratory
  • South Dakota School of Mines and Technology
  • The University of Maryland
  • Texas A&M University
  • The University of California, Davis
  • University College London
  • LIP Coimbra, Portugal
  • The University of South Dakota
  • Lawrence Berkeley National Laboratory
  • The University of California, Berkeley
  • The University of California, Santa Barbara
  • Yale University



  • LUX filled with liquid xenon

    February 4, 2013

    On Sunday researchers working on the Large Underground Xenon (LUX) experiment finished filling the dark matter detector with liquid xenon.

    The process had begun Thursday. Yale University physicist Dan McKinsey, a spokesman for LUX, was underground that morning, but he pointed out that most of the work was being done by young postdocs and even younger graduate students.

  • LUX water tank filled, dark matter search nears

    November 3, 2012

    The Large Underground Xenon dark matter detector, nicknamed LUX, has been fully submerged in water in a large stainless steel tank 4,850 feet underground in the Davis Campus.

    “This is a major step forward on the road to an operational detector in early 2013,” said Sanford Lab Director Mike Headley said. (Read the Sanford Lab press release here. See our In the News page for media coverage.)

  • LUX heading to planetariums

    September 2, 2012

    A noted astronomer and photographer from the Adler Planetarium in Chicago recently visited the 4850 Level to shoot time-lapse images for a new planetarium show about dark matter.

    José Francisco Salgado is the director of photography for “Dark Secret of the Big Bang,” which is being produced by physicist Michael Barnett of Lawrence Berkeley National Laboratory.

    “Dark Secret” will include time-lapse photography and animations from the Sanford Lab and from the Large Hadron Collider at CERN in Switzerland.