Hyperfine Structure Measurements on Plutonium-239

Abstract

The atomic hyperfine structure of plutonium-239 has been investigated by the atomic-beam magnetic resonance method. Research has centered about a relatively highly populated electronic energy level having unit angular momentum which is probably the first excited state of a ground-state ${}_{}{}^7{}_{}{}^{}F$ term arising from the configuration ${\mathrm{}\left(5f\right)\mathrm{}}^6{\mathrm{}\left(6d\right)\mathrm{}}^0{\mathrm{}\left(7s\right)\mathrm{}}^2$. Atomic and hyperfine structure constants for this level are found to be $I=\frac{1}{2}$, $J=1\mathrm{}$, $g_J=1.4975\mathrm{}\pm 0.0010$, $\Delta \nu =7.683\mathrm{}\pm 0.060$ Mc/sec.