June 17, 2020
The XENON1T detector, tucked into an Italian mountainside to search for signs of a mysterious substance in the universe called dark matter, has picked up a new bump in the data that cannot be explained by current models.
An analysis of this excess signal, led by physicists from the University of Chicago, the University of California, San Diego, and the University of Zurich and vetted by the entire XENON collaboration, suggests that it may be evidence of new physics—or an unexpected radioactive contaminant. The results were announced in a seminar on June 17.