Determination of the hyperfine structure of the level 32P32/ of23Na by time-resolved level-crossing spectroscopy

Abstract

Fluorescence from the 3²P states of sodium was studied as a function of time and magnetic field. By the use of a computer the signals were biased in favour of the longer-lived atoms and integrated over time. The improved resolution of the resulting level-crossing curves allowed the positions of level crossings to be determined with improved accuracy. Satisfactory agreement between theory of the line shape and experimental profiles was obtained after allowance had been made for the non-uniform spectral distribution of the exciting radiation; it was also necessary to allow for a small temperature-dependent component of the signal. An iterative analysis of the level-crossing curves leads to the values a=18.7+or-0.1 MHz, b=3.0+or-0.2 MHz for the hyperfine interaction constants of the level 3²P₃2/. These results are compared with those of other authors for the same level and for the level 4²P₃2/.