The atomic-beam magnetic resonance method has been applied to measure the h.f.s. separation of the ground state of H and D by observing frequencies of the r-f field required to induce transitions among certain of the magnetic levels of the h.f.s. multiplets in magnetic fields of the order of 1 gauss. The resonance minima were of the theoretical width for transitions which are field independent in the first order. For deuterium we find ${\nu }_{\mathrm{D}}=327.384\mathrm{}\pm 0.003$ Mc which agrees with our previously reported value within the precision claimed for that quantity. For hydrogen we find ${\nu }_{\mathrm{H}}=1420.410\mathrm{}\pm 0.006$ Mc which is less than the value previously reported by 0.06 percent. The ratio of the measured h.f.s. separations, $\frac{{\nu }_{\mathrm{H}}}{{\nu }_{\mathrm{D}}}$, is 4.33867±0.00004.

The h.f.s. separations, ${\nu }_{\mathrm{H}}$ and ${\nu }_{\mathrm{D}}$, may be calculated from known values of the magnetic moment of the proton, ${\mu }_p$, and the magnetic moment of the deuteron, ${\mu }_d$. The measured ${\nu }_{\mathrm{H}}$ and ${\nu }_{\mathrm{D}}$ are larger than the calculated values by 0.24 percent and 0.26 percent, respectively. The ratio $\frac{{\nu }_{\mathrm{H}}}{{\nu }_{\mathrm{D}}}$ may be calculated from the known ratio $\frac{{\mu }_p}{{\mu }_d}$ using the ordinary reduced mass correction (discussed in the section entitled "Discussion of Results" of this paper). This ratio is independent of ${\alpha }^2$ and $R_{\infty }$. The calculated ratio is found to be higher than our value by 0.017 percent. This discrepancy is 18 times the probable error in our measurements.

Close

PrevNext

View figure in article