Determination of the Dipole Moment and Isotope Shift of RadioactiveHg197by "Double Resonance"

Abstract

Paramagnetic resonance was established between $m$-sublevels ($\Delta m=\pm 1$, $\Delta F=0\mathrm{}$) of the ${}_{}{}^3{}_{}{}^{}P_1^{}{}_{}{}^{}$ state of radioactive ${\mathrm{Hg}}^{197}$ at 3000 Mc/sec. From these data the nuclear interaction constant $A$ was found to be (513.5±1)×${10}^{-3\mathrm{}}$ ${\mathrm{cm}}^{-1\mathrm{}}$, and barring hfs anomalies it lead to a ratio of moments $\frac{{\mu }_{197}}{{\mu }_{199}}=\frac{A_{197}}{A_{199}}=1.045\mathrm{}$; further, the nuclear spin of ${\mathrm{Hg}}^{197}$ was ascertained to be ½. The double resonance was combined with magnetooptic scanning to give the isotope shift of ${\mathrm{Hg}}^{197}$, which was found to be in the 2537 A line + (91±5)×${10}^{-3\mathrm{}}$ ${\mathrm{cm}}^{-1\mathrm{}}$ from ${\mathrm{Hg}}^{198}$. The radioactive mercury was produced by the ${\mathrm{Au}}^{197}(d, 2n){\mathrm{Hg}}^{197}$ reaction and used in vapor form. Satisfactory signals were obtained with as few as 3×${10}^{12}$ atoms.