Physicists Mine Cosmic Answers Deep Underground
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A Mile Below the Earth's Surface, Lab Experiments Focus on Dark Matter, Other Mysteries
LEAD, S.D.At 7:30 a.m. on a recent Tuesday, about a dozen scientists pulled on steel-toed boots and filed into a steel cage that once ferried hundreds of gold miners to work.
Their destination: a new laboratory 11 minutes and a mile beneath the earth's surface that could deliver answers to some cosmic questions.
While scientists at CERN in Europe have been grabbing headlines recently by using an enormous accelerator in a hunt for the Higgs boson particle, the team here at the Sanford Underground Research Facility have lofty goals of their own but a very different approach.A hallway in the former Homestake gold mine in South Dakota, which has been converted into a physics lab in recent years.
They are betting on the power of the quiet, sheltered darkness of the former Homestake gold mine to, among other things, help find dark matter, the so-far invisible particles that are believed to make up as much as 25% of the universe's mass.
The earth's surface is bombarded with tiny particles that come from outer space, and they create a noisy setting for experiments. By placing the lab a mile underground, fewer particles reach the experiments, which allows scientists more control when trying to examine different particle interactions