Possible dark matter signal detected

Scientists searching for the mystery of dark matter have recorded an unusual particle interaction that could offer an important clue.  However researchers say it is too early to call it a discovery.

The signal was detected by the LUX-ZEPLIN (LZ) experiment at the Sanford Underground Research Facility in South Dakota nearly a mile underground.

The LZ experiment uses around 10 tons of highly pure liquid xenon to search for WIMPs (Weakly Interacting Massive Particles) which are among the leading theoretical candidates for dark matter.

During the experiment scientists found a signal that is difficult to explain using known background processes.  The signal had a statistical significance of 2.6 sigma after accounting for the “look elsewhere effect.” This is below the level normally required to confirm a scientific discovery.

Scientists believe about 85% of the matter in the universe is dark matter. It cannot be seen directly but its presence is inferred from the gravitational effects it has on galaxies and large scale structures in the universe.

The LZ team will continue collecting data. If the signal becomes stronger with future observations it could mark a major step forward in the search for dark matter. If it disappears it may turn out to be an unknown background effect instead.