The DarkSide-50 experiment at the Gran Sasso National Laboratory in Italy has completed its experimental run, the research collaboration announced today (Feb. 21). The experiment did not find any potential dark matter particles, but it did demonstrate that the technology could reject “false positive” signals from natural radioactivity or other sources. That will give researchers more confidence in data from the next, larger experiment, DarkSide-20k.
Four UC Davis physicists – Associate Professor Emilija Pantic, postdoctoral researchers Tessa Johnson and Luca Pagani, and graduate student Ben Schlitzer – are members of the DarkSide-50 research collaboration, which includes scientists from a number of universities in the U.S., Europe, Russia and Brazil. Pantic’s laboratory focuses on detecting rare particles, such as neutrinos or candidates for dark matter, with detectors based on liquid argon.
The DarkSide-50 experiment was based on a cylinder containing 50 kilograms of liquid argon. Particles entering the chamber would set off a tiny flash of light that could be detected and analyzed.
The experiment was designed to search for Weakly Interacting Massive Particles, or WIMPs, a possible candidate for the “dark matter” thought to make up much of the universe. DarkSide-50 is a prototype for the much larger DarkSide-20k experiment, which should have an enhanced ability to detect dark matter. DarkSide-20k is expected to begin operating in 2021.
UC Davis physicists also took part in the LUX dark matter experiment at the Sanford Underground Research Facility in Lead, South Dakota.
Construction and operation of the DarkSide-50 detector was supported by the U.S. National Science Foundation, the Italian Istituto Nazionale di Fisica Nucleare, the U.S. Department of Energy, the Russian Science Foundation, the Polish National Science Center and the Foundation for Polish Science. The project also received financial support from the French Institut National de Physique Nucléaire et de Physique des Particules, the UnivEarthS Labex program of Sorbonne Paris Cité, and from the São Paulo Research Foundation (FAPESP), Brazil.