Studies of the interference effect in mixed-type forbidden lines with hyperfine structure are reported. Hyperfine structure and Zeeman patterns at various magnetic fields were obtained for three lines of Bi I and one line of Bi II. Differences in intensity distribution for patterns observed in the L and π directions (ΔM = ±1 components) caused by the interference between electric-quadrupole (EQ) and magnetic-dipole (MD) radiation were looked for. Since the number of Zeeman components is very large (in hundreds), only a general contour of a line broadened by the field could be observed. A special computer program was designed to obtain the predicted contour for various values of the mixing ratio of EQ and MD radiation. The external parameters entered into the program are the J and I values; gJ, A, and B hyperfine-structure constants for each level involved; and the magnitude of the external magnetic field. The selection of profiles best matching the experimental patterns leads to an estimate of the EQ admixture in a given spectral line. The values found were 2.5 ± 0.5% for 4597 Å, 6.5 ± 0.5% for 4615 Å, and 16 ± 1% for 6476 Å of Bi I and 3 ± 1% for 4850 Å of Bi II.
© 1987 Optical Society of America
Jolanta Czerwinska, "Computer simulation of experimental Zeeman-effect patterns of forbidden lines of Bi I and Bi II and estimation of electric-quadrupole admixture in mixed-type radiation," J. Opt. Soc. Am. B 4, 1349-1357 (1987)