The Nuclear Moments of Technetium-99

The hyperfine structure in the optical spectrum of technetium has been investigated in the region 3600-7000A with a Fabry-Perot interferometer crossed with a quartz prism spectrograph. The light source was a liquid-nitrogen-cooled hollow cathode discharge tube. The nuclear-spin, magnetic moments previously reported by one of us are confirmed ($I=\frac{9}{2}\hslash$ and $\mu =5.5\mathrm{}\pm 0.3$ nm) and are in agreement with a more recent nuclear induction measurement. The quadrupole moment of ${\mathrm{Tc}}^{99}$ is found to be: $Q=(+0.34\mathrm{}\pm 0.17)\times {10}^{-24\mathrm{}}$ ${\mathrm{cm}}^2$.