Experimental Determination of Transition Probabilities and Stark Widths of S I and S II Lines

Absolute transition probabilities and Stark widths for some prominent multiplets of S I and S II have been determined experimentally. A wall-stabilized arc was operated in SO₂ with a small hydrogen admixture. The spectroscopic measurements were performed photoelectrically. Side-on observations were transformed via the Abel inversion to give the radial dependence of the measured quantities. Measurements of the absolute intensity of O I lines and the width of H_β served for the plasma analysis; the results of these measurements together with the application of equilibrium and conservation relations for arc plasmas enabled the determination of the temperature and various particle densities. Mass-separation effects are taken into account. The measured Stark widths generally agree well with values calculated from Stark-broadening theory; in the case of the S II lines the agreement with recently calculated values is substantially better than that with earlier theoretical data.