Hfs Separations and Hfs Anomalies in theP122State ofGa69,Ga71,Tl203, andTl205

By use of the method of atomic beam magnetic resonance, the ground-state hyperfine structure splittings in the two common gallium and thallium isotopes have been measured. The measured values are: $\Delta \nu \left({\mathrm{Ga}}^{69}\right)=(2677.9875\mathrm{}\pm 0.0010)\times {10}^6$ ${\sec }^{-1\mathrm{}}$, $\Delta \nu \left({\mathrm{Ga}}^{71}\right)=(3402.6946\mathrm{}\pm 0.0013)\times {10}^6$ ${\sec }^{-1\mathrm{}}$, $\Delta \nu \left({\mathrm{Tl}}^{203}\right)=(21\mathrm{}105.447\pm 0.005)\times {10}^6$ ${\sec }^{-1\mathrm{}}$, and $\Delta \nu \left({\mathrm{Tl}}^{205}\right)=(21\mathrm{}310.835\pm 0.005)\times {10}^6$ ${\sec }^{-1\mathrm{}}$. A comparison of the ratio of the dipole coupling constants in the ground state of the two isotopes with the ratio of the nuclear $g_I$ factors yields the hfs anomaly. Theoretical and experimental values of the anomaly are compared.