Cryogenic fountain development at NIST and INRIM: preliminary characterization

• Published in: IEEE transactions on ultrasonics, ferroelectrics, and frequency control Vol. 57; no. 3; pp. 600 - 605
• Main Authors: Levi, F., Calosso, C., Calonico, D., Lorini, L., Bertacco, E.K., Godone, A., Costanzo, G.A., Mongino, B., Jefferts, S.R., Heavner, T.P., Donley, E.A.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: New York, NY IEEE 01.03.2010; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Blackbody; Cryogenics; Electromagnetic heating; Exact sciences and technology; Ferroelectric materials; Frequency; Frequency control; Frequency standards; Interrogation; Laboratories; Measurements common to several branches of physics and astronomy; Metrology, measurements and laboratory procedures; Microwaves; NIST; Nitrogen; Physics; Temperature dependence; Testing; Time and frequency; Uncertainty; Atomic standard; Microwave radiation; Cryogenics; Cesium; Frequency measurement; Cryogenic temperature; Atomic clocks

This paper describes the new twin laser-cooled Cs fountain primary frequency standards NIST-F2 and ITCsF2, and presents some of their design features. Most significant is a cryogenic microwave interrogation region which dramatically reduces the blackbody radiation shift. We also present a preliminar...