Optogalvanic spectroscopy of the hyperfine structure of the $5p^65d$ ${}^2D_{3/2,5/2}$ and $5p^64f$ ${}^2F^o_{5/2,7/2}$ levels of La III

Abstract

We measure the hyperfine structure of the 5p 6 5d 2 D 3/2 , 5p 6 5d 2 D 5/2 , 5p 6 4f 2 F o 5/2 , and 5p 6 4f 2 F o 7/2 levels in doubly-ionized lanthanum (La III; La 2+ ) in a hollow cathode lamp using optogalvanic spectroscopy. Analysis of the observed spectra allows us to determine the hyperfine A coefficients for these levels to be A D3/2 = 412( 4) MHz, A D5/2 = 20(5) MHz, A F 5/2 = 319(2) MHz, and A F 7/2 = 155(4) MHz; and provide estimates for the hyperfine B coefficients as B D3/2 = 105(29) MHz, B D5/2 = 157(40) MHz, B F 5/2 = −2(53) MHz, and B F 7/2 = 171(51) MHz.