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Online-Workshop "Round & Established 2022“


At the end of August 2022, the online workshop "Round & Established 2022" of the participants of the "Si-Trust" took place. The workshop included 14 groups and 14 time zones and therefore met for 4 hours each on two days. The contributions from 11 of the participating institutes described the experience in handling Si-spheres provided to them by PTB after the "Round & Ready" workshop (2016). Due to the COVID pandemic, the exchange already planned for 2020 was significantly delayed.

The challenges of mass determination of a sphere with a diameter of about 10 cm were solved differently. The colleges reported on the development of tools, the application of the cleaning procedure, and the results achieved. During the workshop, PTB also presented the possibilities of the Digital Calibration Certificate (DCC) for Si spheres as mass standards ("Mass DCC").

Finally, it can be summarised that the challenges have been accepted and good results could be achieved. The sphere could be confirmed as a stable mass standard.




Dorothea Knopf, FB 1.1, eMail: Opens local program for sending emaildorothea.knopf(at)ptb.de