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CIPM, 2003: Recommendation 1
Version française
 
Revision of the Mise en Pratique list of recommended radiations*

The International Committee for Weights and Measures,

considering that

  • improved frequency values for radiations of some high-stability cold ion standards already documented in the recommended radiations list have recently become available;
  • improved frequency values for the infra-red gas-cell-based optical frequency standard in the optical telecommunications region, already documented in the recommended radiations list, have been determined;
  • femtosecond comb-based frequency measurement for certain iodine gas-cell standards on the subsidiary recommended source list have recently been made for the first time, leading to signicantly reduced uncertainty;

proposes that the recommended radiation list be revised to include the following:

  • updated frequency values for the single trapped 88Sr+ ion quadrupole transition and the single trapped 171Yb+ octupole transition;
  • an updated frequency value for the C2H2-stabilized standard at 1.54 µm;
  • updated frequency values for the I2-stabilized standards at 543 nm and 515 nm.


Reference:
Procès-Verbaux des Séances du CIPM (2003), p. 146
Metrologia, 2003, 41(1), 99-108

Note:

Further updates are available on the BIPM website at
http://www.bipm.org/en/publications/mises-en-pratique/standard-frequencies.html.
 
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