Experimental Innovation Allows New Look at Plutonium Behavior at Extreme Conditions

Plutonium diffraction experiments at Lawrence Livermore National Laboratory in Livermore, California, are enabling researchers, for the first time, to test theoretical models about how plutonium behaves at high-pressure conditions.

The theoretical models are a key input for stockpile stewardship simulations to maintain and verify the nation’s nuclear deterrent.

“These experiments provide important new data on plutonium for our stockpile stewardship simulations,” said Phil Calbos, principal assistant deputy administrator for the National Nuclear Security Administration’s Office of Defense Programs. “We congratulate the LLNL team for their continued innovation that will be key to improving our ability to maintain and verify the nation’s nuclear arsenal.”

Last month NNSA researchers carried out the eighth plutonium diffraction experiment at LLNL’s National Ignition Facility. As the world’s largest and highest-energy laser system, NIF’s extreme temperatures, densities and pressures allow researchers to focus on the atomic structure of plutonium at conditions relevant to nuclear weapons.

LLNL researchers used a newly developed double backlighter platform to collect data twice during the most recent experiment. This development lets researchers explore the phase changes of plutonium, one of the most complex elements known to man.