  This paper gives the 2006 self-consistent set 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 also may be found
on the World Wide Web at physics.nist.gov/constants.
