Measurements of a key radioactive decay nudge a nuclear clock closer to reality
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. The measurement of the energy released in the decay is seven times as precise as estimates based on different types of decays, researchers report in the May 25 Nature. The improved energy measurement could galvanize work toward the first nuclear clock, which would follow in the footsteps of atomic timepieces. “We have already amazing atomic clocks which run very precisely,” says nuclear physicist Sandro Kraemer of KU Leuven in Belgium. Those atomic clocks are based on the physics of the electrons that surround an atom (SN: 10/5/17). A nuclear clock would be based on the atom’s nucleus. Some scientists believe nuclear clocks...