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The National Nuclear Security Administration (NNSA) changed the design for the nuclear core of a planned intercontinental ballistic missile warhead late last year, a senior agency official said Tuesday. Altering the design of the W87-1 plutonium pit, being developed by the agency’s Lawrence Livermore National Laboratory in California for the Air Force’s planned Sentinel missile, will delay the first copy of the crucial weapon component by about a year, said Marvin Adams, deputy administrator for defense programs at NNSA. “The…
