Measurements of a key radioactive decay nudge a nuclear clock closer to reality

Scientists detected light emitted when a special type of thorium nucleus decayed

An overhead photo of the nuclear physics facility ISOLDE at CERN.

To observe a radioactive decay that’s key to building a nuclear clock, scientists used the nuclear physics facility ISOLDE at CERN near Geneva (pictured).

CERN

Hickory dickory dock, this nucleus could make a great clock.

A special variety of the element thorium hosts an atomic nucleus that could be used to keep time, scientists say. In a first, researchers have measured a type of decay of this thorium nucleus that releases a single particle of light.