Title :
First comparison of remote cesium fountains
Author :
Parker, T. ; Hetzel, P. ; Jefferts, S. ; Weyers, S. ; Nelson, L. ; Bauch, A. ; Levine, J.
Author_Institution :
Nat. Inst. of Stand. & Technol., Boulder, CO, USA
fDate :
6/23/1905 12:00:00 AM
Abstract :
The frequencies of the cesium fountain primary frequency standards at the National Institute of Standards and Technology and the Physikalisch-Technische Bundesanstalt have been compared. Two-way satellite time and frequency transfer and GPS carrier-phase were the principal frequency-transfer techniques used to make the comparison. For the 15-day interval in which both fountains were in operation the frequencies were compared with an additional uncertainty due to the comparison process of only 6.2 × 10-16. The two standards agree within their stated one-sigma uncertainties of ~ 1.7 × 10-15
Keywords :
Global Positioning System; atomic clocks; caesium; frequency standards; measurement uncertainty; synchronisation; transfer standards; Allan deviation; Cs; GPS carrier-phase; NIST standards; PTB standards; TWSTFT; additional uncertainty; cesium fountain; primary frequency standards; Atomic clocks; Atomic measurements; Extraterrestrial measurements; Frequency; Global Positioning System; Masers; NIST; Satellites; Stability; Uncertainty;
Conference_Titel :
Frequency Control Symposium and PDA Exhibition, 2001. Proceedings of the 2001 IEEE International
Conference_Location :
Seattle, WA
Print_ISBN :
0-7803-7028-7
DOI :
10.1109/FREQ.2001.956161
