Dark Matter Scientists In South Dakota Found A Single Interaction They Cannot Explain
Scientists from the LUX-ZEPLIN experiment, 250 researchers and engineers from 39 institutions operating a detector buried nearly a mile underground in a former gold mine in the Black Hills of South Dakota, presented results Tuesday at a conference in Japan that have the physics world cautiously electrified.
The experiment uses 10 tonnes of ultrapure liquid xenon to detect weakly interacting massive particles, or WIMPs, one of the leading candidates for what dark matter actually is.
After years of data collection, the LZ team recorded a single particle interaction that behaves the way a WIMP would be expected to behave, and that they cannot explain using any known background signal from ordinary matter.
"This event just won't go away even after many, many checks," said University of Sydney physicist Dr. Theresa Fruth. "It's also kind of scary to think, 'Oh, this could be it.'"
They are not claiming it is dark matter. The single event does not meet the five-sigma statistical threshold required to declare a discovery, that would require multiple confirmed interactions. "Importantly, as it's just a single event, we are not claiming that it is dark matter," said researcher Eriksen. "We may be looking at something extraordinary, but we have to be exceptionally rigorous before drawing that conclusion."
Dark matter makes up approximately 85 percent of all matter in the universe, everything visible, from stars to planets to people, is the remaining 15 percent. It has never been directly detected. The LZ experiment will continue collecting data until at least 2028.
