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Panoramic view of the clock hall at PTB with the four caesium clocks CS1, CS2, CSF1 and CSF2.

Unit of Time

Working Group 4.41

Sequence of operations in a measurement cycle

Scheme of operation of a fountain frequency standard, illustrated as a time sequence from left to right. Laser beams are represented by red arrows, white arrows inidcate that the laser beams are blocked.

Schematic of operation of a fountain frequency standard, illustrated as a time sequence