the ytterbium single-ion clock and the caesium fountain clock of PTB. Credit must be given to the creator.

Even your Macbook or smartphone displays time which is synchronized to the NIST-F1 clock, a cesium fountain atomic clock (aka the ‘Atomic Clock’) that is part of a global consortium of atomic ...

Clearly that’s not good enough for a clock at CERN, the European Laboratory for Nuclear Research, where [Daniel] works as an RF engineer. With access to a 10-MHz timebase from a cesium fountain ...

A feedback loop is also used to stabilize the 578-nm laser frequency to the clock transition. Absolute frequency measurements are carried out relative to a local caesium-fountain primary frequency ...