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2018 Samuel Wesley Stratton Award

Rabb, Vocke

Rabb, Vocke


Drs. Rabb and Vocke are recognized for extraordinary contributions to an international effort to redefine the kilogram. They developed a unique analytical method and corrected a previously unknown source of measurement bias that resolved disagreements among the results of different national metrology institutes. Their exceptional insights enable, for the first time, consensus measurements of the Avogadro constant, and by extension the Planck constant, at a level needed for the redefinition of the kilogram.


Savelas A. Rabb

Research Chemist
Material Measurement Laboratory

Robert D. Vocke

Physical Scientist
Material Measurement Laboratory