Physicists utilizing the LUX-ZEPLIN (LZ) dark matter detector deep underground in a former South Dakota gold mine say they’ve recorded a single particle interplay that they’ll’t simply clarify, however they’re a good distance from claiming a discovery.
To seek for darkish matter, LZ makes use of photomultiplier tubes (proven right here earlier than set up within the detector) to seize gentle from particle interactions. Picture credit score: Matthew Kapust / Sanford Underground Analysis Laboratory.
The LZ experiment is a world collaboration of 250 scientists and engineers from 39 establishments.
The detector makes use of 10 tons of ultrapure liquid xenon 1.6 km (one mile) beneath floor on the Sanford Underground Analysis Facility in South Dakota.
Managed by Lawrence Berkeley Nationwide Laboratory, it’s optimized to search for WIMPs (weakly interacting huge particles).
“We anticipate darkish matter interactions to be extraordinarily uncommon, so it wouldn’t take many to characterize the primary actual detection of darkish matter,” mentioned Dr. Carmen Carmona, chief of the LZ experiment group at Penn State.
“That’s why even a single occasion stands out to us. Actually, this specific sign got here from a area of the dataset we hadn’t beforehand examined, and it took our group months of extra work on understanding potential causes of backgrounds to rule out typical explanations for it.”
The LZ group analyzed 220 stay days of information collected between March 2023 and April 2024, this time looking for a broader vary of potential WIMP interactions that would deposit extra vitality within the detector than earlier searches lined.
If attributable to darkish matter, the particle accountable would seemingly have a mass of at the least 200 GeV/c2 (gigaelectronvolts), or greater than 200 occasions the mass of a proton, suggesting a extra unique interplay than the only theoretical fashions predict
The sign stays properly in need of the 5-sigma threshold physicists require to say a discovery. The brand new evaluation stands at 2.6 sigma, that means there’s roughly a 0.5% likelihood it’s merely a statistical fluke from recognized backgrounds.
“We’re very intrigued to see this occasion within the information, within the area the place we anticipate darkish matter to indicate up and the competing backgrounds are very low,” mentioned Brown College’s Professor Rick Gaitskell, spokesperson for LZ.
“With just one occasion, we don’t wish to get forward of ourselves. We’re not claiming to have seen darkish matter.”
“However now we have seen one thing fascinating that we wish to share with the scientific group for his or her enter.”
The group’s results can be submitted to the journal Physical Review Letters.
