Lawrence Livermore National Laboratory recently conducted an experiment on weapons-grade plutonium to assess how resilient a nuclear weapon will prove when it comes up against an adversary’s missile defenses.
The experiment was conducted at the lab’s National Ignition Facility (NIF), where fusion ignition, or the output of more energy than was input, was first achieved from the facility’s laser system. At the NIF, weapons-grade plutonium samples were exposed to “intense, pulsed thermonuclear neutron radiation” to recreate conditions a weapon would encounter from adversarial missile defense systems, according to a lab press release.
Such a weapon could include the W87-1 warhead that will be centered with a plutonium pit, or the warhead’s fissile reactive core that is being developed by the National Nuclear Security Administration.
“This experiment demonstrates how cutting-edge science drives nuclear weapon design and production,” Lawrence Livermore Deputy Director for Strategic Deterrence Brad Wallin said in the lab’s press release Monday. “By providing first-of-its-kind data on plutonium performance, NIF gives us the insight we need to modernize the stockpile and ensure the nation’s deterrent remains credible for the future.”
A newly manufactured warhead based on a previously tested design, W87-1 will be the second of two warheads – the first being the W87-0 – to tip the Air Force’s silo-based Sentinel intercontinental ballistic missile, the replacement for Boeing’s Minuteman III, some time next decade. The first W87-1 pit was diamond stamped, or verified for the nuclear stockpile, in October 2024.
Los Alamos is supposed to make at least 30 pits a year. Savannah River, facing delays and overruns, is supposed to make at least 50, though NNSA has said either plant could make more in a pinch. In 2023, then-NNSA Administrator Jill Hruby said the Savannah River pit plant would probably have to make more than 50 pits a year as soon as it opens.