Except in horror movies, most scientific experiments don’t start with scientists snooping around narrow, deserted hallways. But a tucked-away location in the recesses of the Department of Energy’s (DOE) Oak Ridge National Laboratory (ORNL) provided exactly what Yuri Efremenko was looking for.
Efremenko, an ORNL researcher and University of Tennessee at Knoxville professor, is the spokesperson for the COHERENT experiment, which is studying neutrinos. The team uses five particle detectors to identify a specific interaction between neutrinos and atomic nuclei. The most abundant particles in the universe, neutrinos are extremely light and have no electric charge. They interact very little with other particles. In fact, trillions pass through the Earth every second, leaving no impression. Needless to say, they’re notoriously difficult to detect.
At first, the team surveyed a bustling area near the Spallation Neutron Source (SNS), a DOE Office of Science user facility at ORNL in Tennessee. The neutrons the SNS produces drive 18 different instruments that surround the SNS like spokes on a wheel. The SNS also produces neutrinos, which fly off in all directions from the particle accelerator’s target. But putting the neutrino detectors on the same floor as the SNS would expose the devices to background particles that would increase uncertainties.