Measurement of the Proton Moment in Absolute Units

Abstract

By measuring the absolute value of the magnetic field and the frequency required for nuclear resonance absorption in a water sample, the gyromagnetic ratio of the proton has been determined to be ${\ensuremath{\gamma}}_{P}=(2.67528\ifmmode\pm\else\textpm\fi{}0.00006)\ifmmode\times\else\texttimes\fi{}{10}^{4}$ ${\mathrm{sec}.}^{\ensuremath{-}1}$ ${\mathrm{gauss}}^{\ensuremath{-}1}$. With this value and Planck's constant the value of the magnetic moment of the proton in absolute units becomes ${\ensuremath{\mu}}_{P}=(1.4100\ifmmode\pm\else\textpm\fi{}0.0002)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}23}$ dyne cm/gauss.A combination of our result with recent measurements of the proton moment in Bohr magnetons by Gardner and Purcell results in a value of $\frac{e}{m}=(1.75890\ifmmode\pm\else\textpm\fi{}0.00005)\ifmmode\times\else\texttimes\fi{}{10}^{7}$ e.m.u. ${\mathrm{gram}}^{\ensuremath{-}1}$.