Hyperfine Structure of the Multipole Lines of Bismuth (Bi i)*

Abstract

Four multipole lines of Bi i 4597, 4615, 5640, and 6476 Å were reinvestigated by means of a high-resolving apparatus. In addition to the hyperfine components corresponding to ΔF = 0, ±1, for the first time components corresponding to ΔF = ±2 were observed in the case of a mixed multipole line (4615 Å). Relative intensities of hyperfine-structure components of multipole lines calculated using the formulas of Hill (for magnetic-dipole radiation) and of Rubinowicz (for electric-quadrupole radiation) are compared with the experimentally observed patterns. For the line 4615 Å, about 20% admixture of electric-quadrupole radiation to the total intensity of the line is found, while for the other three the admixture is estimated not to exceed 10%.