Preventing the spread of nuclear weapons: U-Michigan leads $25M project

March 31, 2014

ANN ARBOR—A University of Michigan engineering professor will lead a new $25 million project to help nations with nuclear power safeguard their materials.

The project also will improve monitoring of nations that don’t observe the international nuclear nonproliferation treaty.

The project, funded by the National Nuclear Security Administration, establishes the Center for Verification Technology. The team from 13 universities will work with eight national labs to analyze nuclear nonproliferation efforts, improve technologies for monitoring weapons-grade materials and detecting secret weapon tests, and train the next generation of nonproliferation experts.

“Preventing the spread of nuclear weapons is one of the top priorities both in the U.S. and around the world,” said Sara Pozzi, associate professor of nuclear engineering and radiological sciences at U-M and director of the new center.

In addition to Pozzi, five U-M professors are part of the collaboration and two emeritus faculty serve on the project’s advisory board.

The international Treaty on the Non-Proliferation of Nuclear Weapons has been in force since 1970, with 190 countries currently abiding by it. Nations without nuclear weapons promise to stay that way, and those with nuclear weapons pledge to disarm. For those with nuclear power, this means oversight by the International Atomic Energy Agency. In particular, the IAEA works with cooperating nations to keep close tabs on special nuclear materials—plutonium, uranium-235 and uranium-233. In high concentrations, these materials can be used to make nuclear weapons.

To confirm the peaceful use of nuclear power, the IAEA inspects sites such as reactors and fuel processing facilities. Inspectors use measurement techniques to verify that the amount and concentration of nuclear material present matches the facility’s records. This way, the international community finds out if nuclear material goes missing.

The collaboration will develop new tools to measure these materials without the costly and time-consuming process of opening the storage containers. One method looks for groups of neutrons emitted when short chain reactions occur, a hallmark of such materials. Pozzi’s group is developing new neutron detectors for these measurements.

However, missing material doesn’t necessarily indicate foul play. It is possible for nuclear materials to build up at valves or bends in piping. This lost material can be found, measured and cleaned up with the help of a radiation imager. As the inventor of an effective room-temperature radiation imager, Zhong He, U-M professor of nuclear engineering and radiological sciences, will head the effort for advanced safeguard tools.

To better understand nuclear measurements, Alfred Hero, the R. Jamison and Betty Williams Professor of Engineering in electrical and computer engineering at U-M, will lead a team examining how data from multiple sensors can be used together to answer nonproliferation questions. The work could result in better methods for detecting nuclear detonations and other potentially threatening activities.

The IAEA also oversees disarmament efforts, such as turning nuclear warheads into reactor fuel.

“In Russia, the Megatons to Megawatts program converted hundreds of metric tons from warheads into nuclear fuel used in the U.S.,” Pozzi said. “In these scenarios, again, we need tools to verify that what is being turned into fuel is indeed a nuclear warhead and not some other form of nuclear material.”

Because the designs of the nuclear warheads are still classified, the detection method has to walk a fine line. The data must be clear enough to confirm that the starting material is highly enriched uranium but fuzzy enough that it doesn’t give away the details of the weapon’s design. Richard Lanza of the Massachusetts Institute of Technology leads the disarmament verification group.

For tracking potential illicit nuclear tests, the team will focus on monitoring seismic activity. Earthquakes and nuclear explosions make the ground shake differently, and each can be traced back to its source. Paul Richards of Columbia University heads these studies.

A team led by Alexander Glaser of Princeton University will scrutinize proposals for future disarmament treaties, looking for gaps in their policies that could allow nuclear materials to fall into the wrong hands. And a group led by Kimberlee Kearfott of U-M will address the generation gap in nuclear nonproliferation expertise.

Other U-M collaborators are chief scientist David Wehe and John Lee, professors in nuclear engineering and radiological sciences. U-M President Emeritus James Duderstadt and NERS Professor Emeritus Glenn Knoll will serve on the project’s advisory board. Other university partners are North Carolina State University, University of Hawaii, Pennsylvania State University, Duke University, University of Wisconsin, University of Florida, Oregon State University, Yale University and University of Illinois.

Laboratory partners include the Princeton Plasma Physics Laboratory and several National Laboratories, including Los Alamos, Lawrence Livermore, Sandia, Lawrence Berkeley, Oak Ridge, Pacific Northwest and Idaho.