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CODATA recommended values of the fundamental physical constants: 2006



Peter J. Mohr, Barry N. Taylor, David B. Newell


The paper give the 2006 self-consistent set of values of the basic constants and conversion factors of physics and chemistry recommended by the Committee on data for Science and Technology (CODATA) for international use. Further, it describes in detail the adjustment of the values of the constants, including the selection of the final set of input data based on the results of least-squares analyses. The 2006 adjustment takes into account the data considered in the 2002 adjustment as well as the data that became available between 31 December 2002, the closing date of that adjustment, and 31 December 2006, the closing date of the new adjustment. The new data have led to a significant reduction in the uncertainties of many recommended values. The 2006 set replaces the previously recommended 2002 CODATA set and may also be found on the World Wide Web at
Reviews of Modern Physics


Avogadro constant, Boltzmann constant, elementary charge, fine-structure constant, fundamental constants, Josephson effect, Newtonian gravitational constant, particle magnetic moments, particle masses, Planck constant, quantum electrodynamics, quantum Hall effect.


Mohr, P. , Taylor, B. and Newell, D. (2008), CODATA recommended values of the fundamental physical constants: 2006, Reviews of Modern Physics (Accessed April 14, 2024)
Created April 1, 2008, Updated February 19, 2017