About this reference

(For a catalog of this site, see Detailed contents.)

Welcome to the NIST Reference on Constants, Units, and Uncertainty, one of the technical activities of the Fundamental Constants Data Center of the NIST Physical Measurement Laboratory. The contents of this site have been prepared by Peter J. Mohr, David B. Newell, Barry N. Taylor, and E. Tiesinga of the Data Center.

This site was designed, edited and programmed by Michael Douma under the direction of Drs. Taylor and Mohr.

All material has been authored or co-authored by Drs. Mohr, Newell, Taylor and Tiesinga, with the exception of sections otherwise identified. The bibliographic database portion was designed and programmed by Michael Douma and Dr. Mohr.

For details about how this site has changed, see version history.