Second Generation Cesium Fountain Primary Frequency Standards at NIST
نویسنده
چکیده
NIST is currently investigating the design of a second-generation cesium-fountain primary frequency standard. The design goals of this standard include an ultimate frequency inaccuracy of δf/f < 10 and achievable stability better than σy(τ) < 10/τ. This standard is expected to eventually replace NIST-F1, the current U.S. primary frequency standard [1]. In the context of reaching frequency uncertainties of δf/f < 10 it is necessary to review the current limitations of cesium fountain primary standards, as well as limitations imposed by reporting such standards to the Bureau International des Poids et Mesures (BIPM), by comparing standards between national metrology laboratories and by internal uses of the fountain output frequency.
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