Radiation Detection

Researchers at LLNL use their understanding of the interactions of radiation with matter to develop predictive models that aid discovery of new candidate radiation-sensing materials. One example is the development of strontium iodide (SrI2), a material that offers better energy-resolving performance than previous industry-standard sensing materials.

Our researchers have also discovered the first ever energy-resolving plastic radiation-sensing material, which promises better efficiency as a large-size detector (and at a potentially much lower production cost).

Better energy resolution dramatically improves the ability to identify suspect radiation sources and reject nuisance false alarms.

Advanced Data Analytics

LLNL researchers develop technologies that use data analytic capabilities to extract valuable information from massive data streams. Deep neural networks (DNNs) and machine learning offer ways to sift through these data streams for clues about nuclear weapons proliferation.

Data can be found in peer-reviewed scientific journals, local newspaper articles, patent applications, purchase orders for materials or equipment and even job postings for nuclear-relevant skills. This evidence can help detect, characterize and track the status of a state’s nuclear fuel cycle activities, including those that could assist in the clandestine development of nuclear weapons.

Materials Production Detection

Uranium enrichment is an important technology for both civil and military nuclear applications. A nation’s capability to enrich uranium is therefore of extreme interest to the international counterproliferation community.

All enrichment processes work, directly or indirectly, by exploiting the small difference in atomic mass between the uranium-235 and uranium-238 isotopes. The gas centrifuge separation process uses a system known as a “cascade,” in which the output is based on the previous stage.

To detect the production of materials useful for a nuclear weapons program, we model cascades from enrichment facilities.

Weapons Development Detection and Verification

LLNL’s nonproliferation programs focus on detecting and monitoring activities that could indicate a proliferant state’s involvement in a clandestine weapons-development program. These activities could also indicate an interest in acquiring weapons-usable nuclear material, equipment, technology or expertise.

Our R&D efforts concentrate on characterizing the signatures from manufacturing processes, nuclear stockpiles and nuclear explosions. We also develop state-of-the-art instrumentation to verify foreign nuclear fuel cycle and weapons-development activities.

Nuclear Detonation Detection and Forensics

LLNL advances the underlying technical capability for detecting foreign nuclear weapon detonations, both in space and on the ground. A particular focus is on locating, identifying and characterizing low-yield events. Such efforts meet strategic military requirements as well as test ban treaty monitoring and verification obligations. We are continuing R&D in technical nuclear forensics to better characterize special nuclear materials samples pre- and post-detonation. To this end, we mine data from our historic nuclear test program to improve information from prompt signals and fallout samples.