Nuclear reactor safeguards and monitoring with antineutrino detectors

Cubic-meter-sized antineutrino detectors can be used to non intrusively, robustly, and automatically monitor and safeguard a wide variety of nuclear reactor types, including power reactors, research reactors, and plutonium production reactors. Since the antineutrino spectra and relative yields of fissioning isotopes depend on the isotopic composition of the core, changes in composition can be observed without ever directly accessing the core itself. Information from a modest-sized antineutrino detector, coupled with the well-understood principles that govern the core’s evolution in time, can be used to determine whether the reactor is being operated in an illegitimate way. A group at Sandia is currently constructing a 1 ${\mathrm{m}}^{\mathrm{3}}$ antineutrino detector at the San Onofre reactor site in California to demonstrate these principles.