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Comment on the Paper Metrologia 42 49-57 (2005) by K. Szymaniec et al,



Steven R. Jefferts, F Levi


A recent evaluation of the accuracy of National Physical Laboratory (NPL) primary frequency standard NPL CsF1 gives an overall frequency uncertainty of δŅ/Ņ0 = 1 × 10-15. This stated uncertainty includes a correction of a frequency bias of δŅ/Ņ0 = 8 × 10-16{plus or minus} 3 × 10-16 which is attributed by the authors to microwave leakage. We believe that the cause of the frequency bias, its magnitude and its stated uncertainty are in error.


Jefferts, S. and Levi, F. (2006), Comment on the Paper Metrologia 42 49-57 (2005) by K. Szymaniec et al,, Metrologia (Accessed May 28, 2024)


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Created February 1, 2006, Updated February 17, 2017