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Time Department
Dr Patrizia Tavella (Department Director)
Ms Aurélie Harmegnies
Mr Raphaël Legouge
Dr Frédéric Meynadier
Dr Gianna Panfilo
Dr Giulio Tagliaferro
Mr Laurent Tisserand
tai(a)bipm.org
BIPM Time Department
Time scales Time FTP server Time Department Database
The plot allows the monitoring of the accuracy of the TAI scale interval with respect to realizations of the SI second by PSFS.
The BIPM is pleased to announce the publication of the first key comparison report embedding machine-readable versions of the document.
In November 2021 a new record of sixteen different frequency standards operated by eleven laboratories contributed to the accuracy of International Atomic Time TAI. They include three recently developed optical lattice clocks. This achievement is another step towards a future redefinition of the second.
An international collaboration between the NICT, INRIM, INAF and BIPM has successfully achieved the frequency comparison of distant optical clocks using two independent radio techniques, VLBI and IPPP.
Two-Way Satellite Time and Frequency Transfer, improved by the Software-Defined Radio (SDR) receiver, has been used for Circular T calculation for the first time in March 2020.
Starting from March 2020, the BIPM Time Department is providing additional graphical information concerning the use of Primary and Secondary Frequency Standards (PSFS) in UTC.
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