RECENT IMPROVEMENTS IN NIST-F1 AND RESULTING ACCURACIES OF δf/f<7× 10 †
نویسندگان
چکیده
Since our last publication describing the accuracy budget for NIST-F1 (a laser-cooled Cs fountain primary frequency standard) we have made many improvements resulting in nearly a factor of 2 reduction in the uncertainty in the realization of the SI second. Recently we reported a combined standard fractional uncertainty of 0.67×10.
منابع مشابه
NIST-F1: recent improvements and accuracy evaluations∗
In the last several years we have made many improvements to NIST-F1 (a laser-cooled Cs fountain primary frequency standard at the National Institute of Standards and Technology (NIST) in Boulder, Colorado) resulting in a reduction by over a factor of 2 in the uncertainty of the realization of the SI second. The two most recent accuracy evaluations of NIST-F1 had combined standard fractional unc...
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تاریخ انتشار 2004