The Institute plant had a small spill a few days ago. The chemical released Sunday was liquid cesium sulfate, and it posed no danger to the public, said Larry Kilgore, a shift supervisor at the plant.

Some of the highest levels of radioactive cesium-137, a major by-product of nuclear power generation, are now found in the somewhat salty groundwater beneath sand beaches tens of kilometers away ...

When the cesium second was defined in 1967, it was based on a measurement of the number of cycles of the radiation from a particular cesium-133 transition with reference to the second commonly ...