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Spectroscopy

Constants, Units, and Uncertainty (CODATA)

Every four years, the Committee on Data for Science and Technology (CODATA) issues recommended values of the fundamental physical constants. The values are determined by a least-squares adjustment, based on all the available theoretical and experimental information. The selection and assessment of data is done under the auspices of the CODATA Task Group on Fundamental Constants.

There will be an adjustment of the constants to provide the values for a revision of the International System of Units (SI) expected to take place in 2018.

News and Updates

Projects and Programs

Plasma Metrology

Experimental and computational techniques in support of commercial and scientific uses of plasmas.

Publications

Software

Tools and Instruments

Awards

2015 French Award

The group is recognized for exceptional creativity and dedication in forging and continually improving the world's most comprehensive...

2009 APS Fellow - Yuri Ralchenko

Any active APS member is eligible for nomination and election to Fellowship. The criterion for election is exceptional contributions to the...