The NIST Reference on Constants, Units and Uncertainty Information at the foundation of modern science and technology from the Physical Measurement Laboratory of NIST

CODATA Internationally recommended values of the
Fundamental Physical Constants

The same general procedures were used in the CODATA 2010 adjustment of the values of the constants as in earlier adjustments, for example that of 2006, which is the immediate predecessor of that of 2010. The paper describing in detail the CODATA 2006 adjustment was published simultaneously in two journals and is available to readers electronically:

P. J. Mohr, B. N. Taylor, and D. B. Newell, Rev. Mod. Phys 80(2), 633-730 (2008)

P. J. Mohr, B. N. Taylor, and D. B. Newell, J. Phys. Chem. Ref. Data 37(3), 1187-1284 (2008)

A preprint of the paper describing in detail the CODATA 2010 adjustment should be available on this site by the end of 2011 or in early 2012. Until then, the reader may find the following summary of key points helpful:

Brief Overview of the CODATA 2010 Adjustment of the Values of the Constants

NIST Standard Reference Database 121

Online: October 1994   -   Last update: June 2011