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Jon Shirley


First Accuracy Evaluation of NIST-F2

Thomas P. Heavner, Steven R. Jefferts, Jon H. Shirley, Thomas E. Parker, Elizabeth A. Donley, Neil Ashby, Stephan E. Barlow, Filippo Levi, Giovanni Costanzo
We report the first accuracy evaluation of NIST-F2, a second generation laser-cooled Cesium fountain primary standard developed at NIST with a cryogenic (Liquid

Comparing Room Temperature and Cryogenic Cesium Fountains

Steven R. Jefferts, Thomas P. Heavner, Thomas E. Parker, Jon H. Shirley, Elizabeth A. Donley, Filippo Levi, Davide Calonico, C Calosso, Giovanni Costanzo, B. Mongino
We have compared the frequency of a room temperature cesium fountain primary frequency standard with that of a cryogenic (~80K) cesium fountain. This comparison

NIST F1 and F2

Thomas P. Heavner, Thomas E. Parker, Jon H. Shirley, Paul D. Kunz, Steven R. Jefferts
The National Institute of Standards and Technology operates a cesium fountain primary frequency standard, NIST-F1, which has been contributing to International
Created March 26, 2019