Now Fully Funded, Innovative Nuclear Monitoring Project Moving Forward

UC Davis Department of Physics Part of Nonproliferation Initiative

WATCHMAN, an international partnership developing new methods for monitoring nuclear reactors, is now fully funded thanks to nearly $12.8 million (£9.7 million) from the United Kingdom’s Fund for International Collaboration. The project is also sponsored by the National Nuclear Security Administration, part of the U.S. Department of Energy.

WATCHMAN is an acronym for Water Cherenkov Monitor of Antineutrinos. The project will test a water-based technology for detecting antineutrinos from reactors. Antineutrinos are harmless particles emitted during fissile nuclear reactions, when the nucleus of an atom splits into smaller parts. Antineutrinos can come from nuclear reactions in space, such as those powering stars, but the radioactive elements in nuclear fuel produce antineutrinos at a steady rate — a telltale sign.

The WATCHMAN detector will be a 50-foot-tall cylinder filled with water and gadolinium, built underground in the Boulby Mine in North Yorkshire, England. Sensors inside the cylinder will keep tabs on antineutrinos from the Hartlepool nuclear power plant, located about 15 miles (25 kilometers) away.

UC Davis is in charge of the WATCHMAN project’s Photosensor Working Group, and will be working with Lawrence Livermore National Laboratory to obtain and test the needed photosensors, worth $17 million. Both undergraduate and graduate students in the UC Davis Neutrino Group — led by Professor Robert Svoboda — have participated in the design and operation of the sensitive detectors required for WATCHMAN. Svoboda’s laboratory has been or is involved with a number of neutrino projects, including the Super-Kamiokande experiment in Japan, the SNO+ experiment (Canada), and the Large Underground Xenon (LUX) dark matter experiment at the Sanford Underground Research Facility in South Dakota.

— Becky Oskin, content strategist in the College of Letters and Science