Title :
The new PTB primary cesium clocks
Author :
Bauch, Andreas ; Fischer, Bernd ; Heindorff, Thomas ; Schroder, Roland
Author_Institution :
Phys.-Tech. Bundesanstalt, Braunschweig, Germany
fDate :
4/1/1993 12:00:00 AM
Abstract :
One of the two primary clocks with a vertically directed cesium beam. CS4, has been running at constant operating parameters as a frequency standard since November 1991. Its main design features are reported. The contributions to its frequency uncertainty connected with C field, cavity phase difference, and second-order Doppler effect are given. The relative frequency difference between CS4 and CS2 averaged over six months is -12×10-15. The measured frequency instability of CS4 is 8×10-12/√τ for sample times τ, 300 s⩽τ⩽20000 s
Keywords :
atomic beams; atomic clocks; caesium; frequency stability; measurement standards; 300 to 20000 s; C field; CS2; CS4; Cs beam; PTB; cavity phase difference; frequency instability; frequency uncertainty; primary clocks; relative frequency difference; second-order Doppler effect; Atomic beams; Clocks; Coils; Detectors; Doppler effect; Frequency; Magnetic shielding; Ovens; Phase detection; Structural beams;
Journal_Title :
Instrumentation and Measurement, IEEE Transactions on
