JPNM

PHYSICAL CONSTANTS

1986 Recommended Values of Some of the Fundamental Physical Constants from the publication Physics Today, August 1987. Editted by Robert E. Zimmerman.

Last changed on October 16, 1995


speed of light in a vacuum    c      2.99792458(1.2) x 10**8 m/s
elementary charge	      e      1.60217733(49) x 10**-19 C
Plank's constant              h      6.6260755(40) x 10**-34 J s
Avogadro constant            N(A)    6.0221367(36) x 10**23 atoms/mole
Unified mass unit             u      1.66 05402(10) x 10**-27 kg
electron rest mass            m(e)   9.1093897(54) x 10**-31 kg
                                     5.48579903(13) x 10-**-4 u
Proton rest mass              m(p)    1.6726231(10) x 10**-27 kg
                                        1.007276470(12) u
Neutron rest mass             m(n)     1.6749286(10) x 10**-27 kg
                                        1.008664904(14) u
Bohr radius                  a(o)      0.529177249(24) x 10**-10m
Classical electron radius      r(e)      2.81794092(38) x 10**-15 m
Bohr magneton                 u(B)      9.2740154(31) x 10**-24 J/T
Nuclear magneton              u(N)      5.0507866(17) x 10**-27 J/T
Electron magnetic moment    u(e)      9.2847701(31) x 10**-24 J/T
Proton magnetic moment       u(p)      1.41060761(47) x 10**-26 J/T
Proton gyromagnetic ratio     p          2.6752212(81) x 10**8 /(sec T)
Radioactivity                 Ci         3.7 x 10**10 Bq

Douglas J. Wagenaar, Ph.D., wagenaar@nucmed.bih.harvard.edu