Long term measurement of the Sr 87 clock frequency at the limit of primary Cs clocks

authored by: R. Schwarz, S. Dörscher, A. Al-Masoudi, E. Benkler, T. Legero, U. Sterr, S. Weyers, J. Rahm, B. Lipphardt, C. Lisdat
Abstract: We report on a series of 42 measurements of the transition frequency of the 429 THz (5s2) S01-(5s5p) P03 line in Sr87 taken over three years from 2017 to 2019. They were performed at the Physikalisch-Technische Bundesanstalt (PTB) between the laboratory strontium lattice clock and the primary caesium fountain clocks CSF1 and CSF2. The length of each individual measurement run has been extended by use of a hydrogen maser as a flywheel to improve the statistical uncertainty given by the Cs clocks. We determine an averaged transition frequency of 429228004229873.00(0.07) Hz with 1.5×10-16 fractional uncertainty at the limit of the current realization of the unit hertz. Analysis of the data provides an improved limit on the coupling of the gravitational potential of the Sun to the proton-electron mass ratio μ and confirms the limits on the temporal drift of μ.
External Organisation(s): Physikalisch-Technische Bundesanstalt PTB
Type: Article
Journal: Physical Review Research
Volume: 2
ISSN: 2643-1564
Publication date: 08.2020
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: General Physics and Astronomy
Electronic version(s): https://doi.org/10.1103/PhysRevResearch.2.033242 (Access: Open)

BibTeX

@article{b131b418f76b4bf295aeb8d99945c5ed,
title = "Long term measurement of the Sr 87 clock frequency at the limit of primary Cs clocks",
abstract = "We report on a series of 42 measurements of the transition frequency of the 429 THz (5s2) S01-(5s5p) P03 line in Sr87 taken over three years from 2017 to 2019. They were performed at the Physikalisch-Technische Bundesanstalt (PTB) between the laboratory strontium lattice clock and the primary caesium fountain clocks CSF1 and CSF2. The length of each individual measurement run has been extended by use of a hydrogen maser as a flywheel to improve the statistical uncertainty given by the Cs clocks. We determine an averaged transition frequency of 429228004229873.00(0.07) Hz with 1.5×10-16 fractional uncertainty at the limit of the current realization of the unit hertz. Analysis of the data provides an improved limit on the coupling of the gravitational potential of the Sun to the proton-electron mass ratio μ and confirms the limits on the temporal drift of μ.",
author = "R. Schwarz and S. D{\"o}rscher and A. Al-Masoudi and E. Benkler and T. Legero and U. Sterr and S. Weyers and J. Rahm and B. Lipphardt and C. Lisdat",
note = "Publisher Copyright: {\textcopyright} 2020 authors. Published by the American Physical Society.",
year = "2020",
month = aug,
doi = "10.1103/PhysRevResearch.2.033242",
language = "English",
volume = "2",
journal = "Physical Review Research",
issn = "2643-1564",
publisher = "American Physical Society",
number = "3",
}