What is believed to be the "most sensitive dark matter detector in the world" has been operating a mile underground in the hills of South Dakota.
"LUX is blazing the path to illuminate the nature of dark matter." Brown University physicist Rick Gaitskell, co-spokesperson for LUX, said, an Interactions.org news release reported.
LUX is an acronym for Large Underground Xenon experiment.
Dark matter can be observed by its gravitational effects on other objects, but other than that is invisible. It is believed to be the "predominant form of matter in the universe."
Some scientists have said Weakly interacting massive particles (WIMPs), which rarely interact with other matter, are actually dark matter. Researchers are yet to discover the mass of WIMPs.
LUX has a sensitivity to this mysterious matter that is three times greater than any past technology and is It is 20 times better at detecting low-mass WIMPs.
"This is only the beginning for LUX," physicist Dan McKinsey of Yale University, said. "Now that we understand the instrument and its backgrounds, we will continue to take data, testing for more and more elusive candidates for dark matter."
Collisions between normal matter and WIMPs are extremely hard to detect because they happen so seldom. Radiation from the Sun can also make it more difficult to pick up on the signals. LUX is located underground in an effort to shield it from this interfering radiation.
"This supremely quiet environment substantially improves our ability to see WIMPs scattering with xenon nuclei," Gaitskell said.
The detector consists of a six-foot-tall tank filled with negative 150 degrees Fahrenheit liquid xenon. If a WIMP interacts with a xenon atom it "recoils" from the other atoms, which releases photons and electrons. The tank has light detectors at its top and bottom to detect these interactions.
"LUX is a complex instrument," McKinsey said. "but it insures that each WIMP event's unique signature of position and energy will be precisely recorded."
"The universe's mysterious dark sector presents us with two of the most thrilling challenges in all of physics," Saul Perlmutter of DOE's Lawrence Berkeley National Laboratory (Berkeley Lab), a winner of the 2011 Nobel Prize in Physics for discovering the accelerating expansion of the universe, said. "We call it the dark sector precisely because we don't know what accounts for most of the energy and mass in the universe. Dark energy is one challenge, and as for the other, the LUX experiment's first data now take the lead in the hunt for the dark matter component of the dark sector."
