High-accuracy measurement of the black-body radiation frequency shift of the ground-state hyperfine transition in 133Cs

Published

February 7, 2014

Author(s)

Steven R. Jefferts, Thomas P. Heavner, Thomas E. Parker, Jon H. Shirley, Elizabeth A. Donley, Neil Ashby

Abstract

We report a high-accuracy direct measurement of the blackbody radiation shift (BBR) of ¹³³Cs ground state hyperfine transition. This frequency shift is one of the largest systematic frequency biases encountered in realizing the current definition of the SI second. Uncertainty in the correction of the BBR frequency shift has led to its being the focus of intense theoretical effort by a variety of research groups. Our experimental measurement of the shift used two laser-cooled primary frequency standards operating at different temperatures. We achieved an uncertainty a factor of five smaller than the previous best direct measurement. These results tend to validate the claimed accuracy of the recently calculated values.

Citation

Physical Review Letters

Volume

112

Pub Type

Journals

Keywords

Blackbody Radiation, Cesium Clock, Primary Frequency Standard

Citation

Jefferts, S. , Heavner, T. , Parker, T. , Shirley, J. , Donley, E. and Ashby, N. (2014), High-accuracy measurement of the black-body radiation frequency shift of the ground-state hyperfine transition in ¹³³Cs, Physical Review Letters (Accessed October 18, 2025)