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The Planck constant, watt and vacuum balances, and an evolving Mise en pratique for the kilogram in North America

Published

Author(s)

Jon R. Pratt, David B. Newell, Zeina J. Kubarych, Stephan Schlamminger, Darine El Haddad, Ruimin Liu, Edwin R. Williams, Dave Inglis, Barry M. Wood, Carlos Sanchez, Richard Green

Abstract

We report preparations underway at the National Institute of Standards and Technology (NIST) in the United States and at the National Research Council (NRC) in Canada to support the redefinition of the international system of units (SI) and the development of a Mise en pratique for the unit of mass. NIST and the NRC possess two of the world’s most precise moving coil watt balances and are developing a collaborative plan to reconcile differences between the respective measurement platforms by testing their ability to mutually realize the kilogram from the Planck constant. The important role to be played by mass metrology and new facilities, such as the NIST magnetic levitation balance and the NRC vacuum comparator, to establish the necessary link between a mass as measured in vacuum and its value in air will be considered.
Proceedings Title
Conference on Precision Electrical Measurements (CPEM) 2012, Conference Digest
Conference Dates
July 1-6, 2012
Conference Location
Washington, DC
Conference Title
Conference on Precision Electromagnetic Measurements 2012

Keywords

fundamental electrical measurements, fundamental constants, mass metrology, watt balance, magnetic levitation balance, vacuum mass, revised SI

Citation

Pratt, J. , Newell, D. , Kubarych, Z. , Schlamminger, S. , El, D. , Liu, R. , Williams, E. , Inglis, D. , Wood, B. , Sanchez, C. and Green, R. (2012), The Planck constant, watt and vacuum balances, and an evolving Mise en pratique for the kilogram in North America, Conference on Precision Electrical Measurements (CPEM) 2012, Conference Digest, Washington, DC (Accessed May 4, 2024)
Created July 1, 2012, Updated December 16, 2019