Washington: The US has successfully conducted a "subcritical" nuclear test at an underground site in Nevada to study the behaviour of nuclear materials without causing an atomic explosion, authorities said.

In subcritical nuclear tests, no critical mass is formed and no self-sustaining nuclear chain reaction can occur; thus, there is no nuclear explosion.
The scientific data gathered through this subcritical nuclear test called Pollux -- the 27th such experiment to date -- will provide crucial information to maintain the safety and effectiveness of US nuclear weapons, National Nuclear Security Administration (NNSA) said in a statement yesterday.
"Challenging subcritical experiments maintain our capabilities to ensure that we can support a safe, secure and effective stockpile without having to conduct underground testing," NNSA Administrator Thomas D`Agostino said. The previous subcritical experiment, Barolo B, was conducted on February 2, 2011. "Diagnostic equipment fielded by our scientists resulted in more data collected in this single experiment than all other previous subcritical experiments," said NNSA Deputy Administrator for Defence Programmes Don Cook.
"This type of data is critical for ensuring our computer simulations can accurately predict performance, and thus continued confidence in the safety and effectiveness of the nation`s stockpile," he said. NNSA said subcritical experiments examine the behaviour of plutonium as it is strongly shocked by forces produced by chemical high explosives.
PTI