J. Phys. Colloques
Volume 42, Numéro C8, Décembre 1981Troisième Symposium sur les Etalons de Fréquence et la Métrologie / Third Symposium on Frequency Standards and Metrology
|Page(s)||C8-233 - C8-240|
J. Phys. Colloques 42 (1981) C8-233-C8-240
PERFORMANCE OF THE NRC PRIMARY TIME STANDARDS CsV, CsVI A, CsVI B, CsVI CA.G. Mungall, H. Daams, J.S. Boulanger et C.C. Costain
National Research Council, Ottawa, Canada.
The 2.1 m NRC primary clock CsV and the three 1 m NRC CsVI primary clocks have estimated limits of accuracy of 1 and 1.5 x 10-13 respectively, and estimated probable accuracies of 5 and 7 x 10-14. The frequency stabilities of all four clocks are similar, with the value of σ (2, τ) approaching 1 x 10-14 for τ = 105 s. Re-evaluations of the accuracy of CsV, performed at yearly intervals, have shown no significant change in this estimate. In addition, comparisons with the cesium standard of the PTB, CsI, made during the past four years, indicate long-term agreement to within a few parts in 1014. No seasonal variation between these two standards is apparent, in contrast with that evident between them and TAI.