Title :
A new microwave synthesis chain for the primary frequency standard NIST-F1
Author :
Heavner, T.P. ; Jefferts, S.R. ; Donley, E.A. ; Parker, T.E. ; Levi, F.
Author_Institution :
Time & Frequency Div., National Inst. of Stand. & Technol., Boulder, CO
Abstract :
We present the design and measurements of the microwave synthesis chain presently used in NIST-F1, the laser-cooled cesium fountain primary frequency standard in operation at NIST, Boulder, CO. The chain has been used in two accuracy evaluations of NIST-F1 (January 2005 and July 2005), each of which had a combined (type A and type B) fractional frequency uncertainty of ~ 0.5 times 10-15. Additionally, this synthesis chain was in use during a recent calibration of the 199Hg+ optical clock transition against Cs, which had a fractional uncertainty of 9.1 times 10-16
Keywords :
caesium; frequency standards; laser cooling; measurement uncertainty; microwave measurement; Cs; NIST-F1; fractional frequency uncertainty; laser-cooled cesium fountain; microwave synthesis chain; optical clock transition; primary frequency standard; Calibration; Frequency measurement; Frequency synthesizers; Masers; Measurement standards; Mercury (metals); Microwave measurements; NIST; Optical design; Uncertainty;
Conference_Titel :
Frequency Control Symposium and Exposition, 2005. Proceedings of the 2005 IEEE International
Conference_Location :
Vancouver, BC
Print_ISBN :
0-7803-9053-9
DOI :
10.1109/FREQ.2005.1573950
