Precision Atomic Spectroscopy for Improved Limits on Variation of the Fine Structure Constant and Local Position Invariance
Abstract
We report tests of local position invariance and the variation of fundamental constants from measurements of the frequency ratio of the 282-nm 199Hg+optical clock transition to the ground state hyperfine splitting in 133Cs. Analysis of the frequency ratio of the two clocks, extending over 6 yr at NIST, is used to place a limit on its fractional variation of <5.8×10−6 per change in normalized solar gravitational potential. The same frequency ratio is also used to obtain 20-fold improvement over previous limits on the fractional variation of the fine structure constant of |˙αα|<1.3×10−16 yr−1, assuming invariance of other fundamental constants. Comparisons of our results with those previously reported for the absolute optical frequency measurements in H and 171Yb+ vs other 133Cs standards yield a coupled constraint of −1.5×10−15<˙α/α<0.4×10−15 yr−1 and −2.7×10−15
Repository Citation
Fortier, T.M., N. Ashby, J.C. Bergquist, M.J. Delaney, et al. 2007. "Precision Atomic Spectroscopy for Improved Limits on Variation of the Fine Structure Constant and Violation of Local Position Invariance." Physical Review Letters 98(7).
Publisher
American Physical Society
Publication Date
1-1-2007
Publication Title
Physical Review Letters
Department
Physics and Astronomy
Document Type
Article
DOI
https://dx.doi.org/10.1103/PhysRevLett.98.070801
Language
English
Format
text