Research

The Antineutrino 

Antineutrinos are emitted by nuclear reactors (among many other natural and artificial sources). As a national security laboratory, LLNL has pioneered what has become a global effort in applied antineutrino physics—exploring antineutrino applications by monitoring nuclear reactors and spent fuel in nonproliferation contexts.

Nuclear reactors, as the birthplace of the world’s plutonium, are of interest from a nonproliferation and national security perspective, and inextricably related to the production and source of antineutrinos in mass quantities. By measuring the rate and energy spectrum of antineutrinos emitted by reactors, the fissile content, operational status, and power level of the reactor can be monitored in near-real-time.

LLNL has a long history of developing technology and using concepts for applied antineutrino physics. A series of experiments performed by Lawrence Livermore and Sandia National Laboratories confirmed that it was possible to extract information about the fissile content of reactor cores with detectors of simple design.

Current efforts include developing technologies to increase sensitivity and/or broaden the utility of antineutrino-based systems, for example:

• Developing detectors that can operate on the Earth’s surface without cosmic ray attenuation
• Inventing solid state materials to facilitate mobility, user acceptance, and new detector concepts
• Investigating large detectors to permit operation at greater standoff distances
• Developing ultra-low threshold detectors to access a higher cross section of neutrino interactions known as coherent scatter
• Working to better understand the practicality of antineutrino detection for end users

Projects