A supercluster of galaxies captured in an image by the Hubble Space Telescope, with invisible dark matter believed to exist in the regions marked in pinkish-purple. Image: Alamy
The new detector will be constructed at Boulby in North Yorkshire, where scientists have established an underground research center to conduct various experiments on materials, the environment, and other subjects, as reported by The Guardian on August 6th. Some initial efforts to detect dark matter particles have also been carried out at this site. The detector will provide an opportunity to determine the origin of one of the universe’s biggest mysteries – dark matter, according to Professor Chamkaur Ghag, a physicist at the University of London.
Scientists are aware that the universe contains more matter than can be directly observed, as they observe galaxies existing in clusters. Surely, there is additional matter generating gravitational forces to maintain these galaxy clusters. But what constitutes this enigmatic dark matter? After eliminating possibilities, most researchers have concluded that weakly interacting massive particles, known as WIMPs, are likely responsible. These subatomic particles with substantial mass are believed to constitute about 85% of the universe’s mass.
However, WIMPs rarely interact with ordinary matter, prompting researchers to build increasingly sensitive detectors to search for them. The detector’s goal is to capture the light emitted when WIMPs collide with the nuclei of xenon atoms. Despite placing the device deep underground, shielded from cosmic rays and surface-level particle collisions, researchers have yet to detect any WIMPs after two decades of searching.
According to Ghag, when the detector reaches a certain sensitivity level in future generations, the signals it can capture from WIMPs might be confused with signals from other particles, such as neutrinos. This limitation is referred to as the “neutrino fog.”
“The next-generation detectors won’t be the last machines ever developed, but as we move towards the neutrino fog, detecting WIMPs will become even more challenging,” said Professor Sean Paling, the director of the Boulby Underground Laboratory. Currently, several research groups are searching for WIMPs in locations including mining caverns in South Dakota as well as centers in Italy, China, and Japan. Last week, a research team in South Dakota reported that they found no evidence of WIMPs in the detectors used in their experiment.