An advanced dark matter detector that hopes to find a rare collision between a dark matter particle and normal matter has just been approved in the US, with a view to starting the search in 2020.
Called LUX-ZEPLIN (LZ), the detector will be built in Lead, South Dakota, at the Sanford Underground Research Facility. A former gold mine, the detector will be placed 1,480 meters (4,850 feet) underground away from any interference and ready to detect dark matter. It will be at least 100 times more sensitive than current detectors, which have so far failed to find any evidence for dark matter.
The approval came last month when the US Department of Energy passed the Critical Decision 2 and 3b reviews, which cover the scope, cost, and schedule of the ambitious project.
“The nature of the dark matter, which comprises 85 percent of all matter in the universe, is one of the most perplexing mysteries in all of contemporary science,” Harry Nelson, LZ spokesperson and a physics professor at the University of California, Santa Barbara, said in a statement.
“Just as science has elucidated the nature of familiar matter – from the periodic table of elements to subatomic particles, including the recently discovered Higgs boson – the LZ project will lead science in testing one of the most attractive hypotheses for the nature of the dark matter.”
So far the mysterious substance has remained elusive. We can see its effects on galaxies, and it is a crucial component of our accurate models of the universe, but we don’t know what it’s actually made of. LZ will be searching for a hypothesized dark matter particle known as a weakly interacting massive particle (WIMP).
To perform the hunt, LZ will use a chamber filled with 10 tonnes (11 US tons) of purified liquid xenon. Flashes of light and electrical pulses will signify particle interactions, and scientists will be hoping some of these hint at dark matter interacting with normal matter.
“Nobody looking for dark matter interactions with matter has so far convincingly seen anything, anywhere, which makes LZ more important than ever,” said Murdock Gilchriese, LZ project director and a physicist at the Lawrence Berkeley National Laboratory in California, in the statement.
Dark matter is believed to interact only through gravity and not with light, hence why it earned the “dark” prefix. Scientists in many disciplines are trying to constrain the properties of dark matter by using astronomical observations and particle smashers like the Large Hadron Collider. Hopefully, LZ will provide the crucial information that we are still missing.
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