#### ${{\mathit \mu}}$ MASS

The mass is known more precisely in u (atomic mass units) than in MeV. The conversion is: 1 u = 931.494 102 42(28) MeV/c${}^{2}$ (2018 CODATA value, TIESINGA 2021 ). The conversion error contributes significantly to the uncertainty of the masses given below.

VALUE (MeV) DOCUMENT ID TECN CHG  COMMENT
$105.6583755$ $\pm0.0000023$
 2021
RVUE 2018 CODATA value
• • We do not use the following data for averages, fits, limits, etc. • •
$105.6583745$ $\pm0.0000024$
 2016
RVUE 2014 CODATA value
$105.6583715$ $\pm0.0000035$
 2012
RVUE 2010 CODATA value
$105.6583668$ $\pm0.0000038$
 2008
RVUE 2006 CODATA value
$105.6583692$ $\pm0.0000094$
 2005
RVUE 2002 CODATA value
$105.6583568$ $\pm0.0000052$
 1999
RVUE 1998 CODATA value
$105.658353$ $\pm0.000016$ 1
 1987
RVUE 1986 CODATA value
$105.658386$ $\pm0.000044$ 2
 1982
CNTR +
$105.65836$ $\pm0.00026$ 3
 1972
CNTR
$105.65865$ $\pm0.00044$ 4
 1971
CNTR
 1 Converted to MeV using the 1998 CODATA value of the conversion constant, $931.494013$ $\pm0.000037$ MeV/u.
 2 MARIAM 1982 give ${\mathit m}_{{{\mathit \mu}}}/{\mathit m}_{{{\mathit e}}}$ = 206.768259(62).
 3 CROWE 1972 give ${\mathit m}_{{{\mathit \mu}}}/{\mathit m}_{{{\mathit e}}}$ = 206.7682(5).
 4 CRANE 1971 give ${\mathit m}_{{{\mathit \mu}}}/{\mathit m}_{{{\mathit e}}}$ = 206.76878(85).
References:
 TIESINGA 2021
RMP 93 025010 CODATA recommended values of the fundamental physical constants: 2018
 MOHR 2016
RMP 88 035009 CODATA Recommended Values of the Fundamental Physical Constants: 2014
 MOHR 2012
RMP 84 1527 CODATA Recommended Values of the Fundamental Physical Constants: 2010
 MOHR 2008
RMP 80 633 CODATA Recomended Values of the Fundamental Physical Constants: 2006
 MOHR 2005
RMP 77 1 NIST Constants
 MOHR 1999
JPCRD 28 1713 CODATA Recommended Values of the Fundamental Physical Constants: 1998;
 Also
RMP 72 351 CODATA Recommended Values of the Fundamental Physical Constants: 1998
 COHEN 1987
RMP 59 1121 CODATA Fundamental Physical Constants 1986 Adjustments
 MARIAM 1982
PRL 49 993 Higher Precision Measurement of the hfs Interval of Muonium and of the Muon Magnetic Moment
 CROWE 1972
PR D5 2145 Precision Measurement of the Magnetic Moment of the Muon
 CRANE 1971
PRL 27 474 Observation of a Quadratic Term in the hfs Pressure Shift for Muonium and a New Precise Value for Muonium $\Delta \nu$