Second

Solutions for Time and Frequency Synchronization

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Second

The SI-System of Units defines the second as an atomic Time normal for reasons of an immense improvement of accuracy and long-term consistency towards astronomic Time standards like the “sun- or ephemeris second”. Due to definition, a second is based on the period of a Microwave which is in resonance with the transition of a caesium atom, multiplied by 9.192.631.770. A second can therefore be described as 9.192.631.770 times the duration of a period of a transition between two special levels of the ground state of the Nuclides of a 133 Caesium atoms radiation. This determination has been introduced to ensure the average duration of one day of sun, which has to conform to the position of the sun being at the same location after one full turn. Because of some irregularities due to the slowing down of the earth rotation leap seconds have been introduced.

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