Working Group Members

CCTF Working Group on Primary and Secondary Frequency Standards (CCTF-WGPSFS)


Dr Stefan Weyers

Physikalisch-Technische Bundesanstalt



Dr Gérard Petit

Bureau international des poids et mesures



Terms of reference

  • to develop and propose standards for the documentation of frequency biases and uncertainties, operational details, and frequency transfer uncertainties for Primary and Secondary Frequency Standards (PFSs and SFSs). Develop and propose standards for the reporting of the results of a PFS/SFS evaluation to the BIPM;
  • to provide a forum to evaluate and discuss the consistency among primary frequency standards;
  • to provide a forum to discuss and assess the overall knowledge of the accuracy of the SI second for use in establishing the frequencies of secondary standards (microwave and optical) and possibly an eventual redefinition of the second;
  • to interact with the BIPM on issues related to PFS/SFS contributions to the accuracy of TAI, particularly in the process of integration of the first reports of a standard;
  • to encourage and facilitate direct comparisons between primary and secondary frequency standards;
  • to encourage and support laboratories with new standards under construction.

List of meetings

Meetings and related documents

CCTF logo

Asset Publisher

Working Groups