MEasurements of the Hydrogen-Deuterium Atomic Magnetic Moment Ratio and of the Deuterium Hyperfine Frequency

The ratio of the hydrogen atomic magnetic moment to that of deuterium has been measured by spin-exchange detection of Zeeman ($\Delta F=0\mathrm{}$, $\Delta m_F=-1\mathrm{}$) transitions in an atomic hydrogen maser. The value of this ratio is found to be 1.000 000 009 4(14) in agreement with a recent theoretical calculation. The spin-exchange technique has also been used to measure the zero-field ground-state deuterium hyperfine frequency. The result is $\Delta \nu \left(\mathrm{D}\right)=327\mathrm{}384352.51\left(5\right)\mathrm{}$ Hz.