The Nuclear Moments of Columbium from Hyperfine Structure

Abstract

The hyperfine structure of the arc spectrum of columbium has been examined under conditions of high resolving power. The line patterns of $\ensuremath{\lambda}\ensuremath{\lambda}4059$, 4080, 4117, 4137, 4168, 4649, 4672, 4675, 5344 and 6661 have been studied in detail. Three relatively independent methods have been used to determine the nuclear mechanical moment, $\frac{{I}^{*}h}{2\ensuremath{\pi}}$. All three methods indicate a value of $\frac{9}{2}$ for $I$, the quantum number of nuclear spin. Using the formulas given by Goudsmit, the nuclear $g$-factor has been calculated to be ${g}_{I}=0.83$. This gives for the nuclear magnetic moment ${\ensuremath{\mu}}_{I}=3.7$ nuclear magnetons.