Using a detector filled with nearly 9 metric tons of liquid xenon, the XENONnT experiment has delivered some of the most sensitive dark matter results ever recorded. In the latest analysis from the XENON collaboration, working deep underground at Italy's Gran Sasso National Laboratory, a blind search found no unexplained signal in 5.9 metric tons of liquid xenon.
The analysis did set unprecedented limits on axion-like particles and light dark matter, producing the most detailed map yet of where dark matter cannot be found. The results rank among the most sensitive direct searches ever performed, further narrowing the possible properties of the elusive particles.
Dark matter is thought to make up roughly 27% of the universe, yet it barely interacts with ordinary matter. Detectors like XENONnT are built to catch the extremely rare recoil a passing dark matter particle would trigger in a xenon atom. So far, every attempt has come up empty — but each null measurement sharpens the picture by ruling out what dark matter cannot be.
The announcement accompanies a Physical Review Letters paper reporting a light dark matter search using 7.83 tonne-years of exposure. As the collaboration keeps collecting data, the question remains whether dark matter will finally be seen directly this decade — or continue to slip out of reach.
