Laser-Induced Nuclear Orientation of 1-μsRbm85

Frequency-resolved laser-induced gamma-ray anisotropy has been achieved and used to measure the $D_1$ hyperfine structure of the 1-μs isomer ${}_{}{}^{85}{}_{}{}^{}\mathrm{Rb}_{}^m{}_{}{}^{}$. The magnetic dipole moment obtained is $(6.046\mathrm{}\pm 0.010){\mu }_N$ and the isomer shift relative to ${}_{}{}^{85}{}_{}{}^{}\mathrm{Rb}$ is —52±9 MHz. The experiment was performed with a sealed cell containing radioactive ${}_{}{}^{85}{}_{}{}^{}\mathrm{Kr}$ (3 mCi) and natural Rb(∼ 10 mTorr). This method is simple and convenient and promises to be of wide usefulness.