Hyperfine Structure in Silver

Abstract

Twenty lines in the visible spectrum, $\ensuremath{\lambda}7688$ in the infrared, and the two resonance lines $\ensuremath{\lambda}3383$ and $\ensuremath{\lambda}3281$ were studied by means of a hollow cathode source and Fabry-Perot interferometers. All lines in the visible were found to be simple in agreement with the findings of other investigators. $\ensuremath{\lambda}7688$ was found to be a very broad line and lines $\ensuremath{\lambda}3383$ and $\ensuremath{\lambda}3281$ were each found to be double with the weaker component on the longer wavelength side. Photographic plates measured gave an average of 0.055 ${\mathrm{cm}}^{\ensuremath{-}1}$ for the separation in $\ensuremath{\lambda}3383$ and 0.056 ${\mathrm{cm}}^{\ensuremath{-}1}$ in $\ensuremath{\lambda}3281$. It is concluded that the doubling of these lines is due to a splitting of the $5S$ level because of nuclear spin which is probably 3/2.