With a wall-stabilized arc source, we have measured the relative transition probabilities of 100 lines of neutral nitrogen in the visible and near-infrared spectrum and have normalized our data to an absolute scale utilizing four recent lifetime results. We estimate that the expanded uncertainties of our data are in the range of +11 -15 %. For a number of 3s -3p and 3p -3d multiplets, we have measured complete sets of lines and observe that most 3p-3d multiplets show considerable departure from LS coupling, while the 3s-3p multiplets adhere to it within +20%. Agreement between intermediate coupling calculations and our experimental data for the 3p-3d multiplets is noticeably better, but significant di6'erences are still encountered for two multiplets originating from the 3d P level.PACS number(s): 32.70.Cs, 32.90.+ a

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Line shapes of P (A, =4686 A) and Pp (A, =3203 A) of He II and of some C Iv lines are analyzed for plasmas in the parameter range 10 m & X, & 5 & 10 m and kT, & 11 eV for the electron density and temperature. The light source is a gas-liner pinch, a quite new device, which is optimized to produce a homogeneous test plasma. The light emission of helium and carbon takes place only from a very limited region of the central plasma. The spectral lines are analyzed with respect to the line broadening and the He u lines additionally to the asymmetry. For the investigation of the CIv lines, transitions were selected which came from different upper energy levels and which were broad and intense enough for a reliable measurement.They cover the wavelength region 948 to 0 5805 A. By comparing the results with different theories, it is found that the experimental values are about a factor of 2 higher than the theoretical ones.

Experimental and theoretical Stark broadening studies of the Paschen beta line of hydrogen (lambda=1.28 microm) are reported. Line shape measurements were performed at electron densities of the plasma between 3.5 x 10(15) cm(-3) and 7.5 x 10(15) cm(-3), applying as the light source a wall-stabilized arc operated at atmospheric pressure in a helium-hydrogen gas mixture. The radiation of the plasma, emitted from nearly homogeneous plasma layers in the end-on direction, was registered with the use of a grating spectrometer equipped with a charge coupled device detector. The measured light outputs were calibrated against signals obtained from a tungsten strip radiation standard. The experimentally determined line profiles are compared with results of new Stark broadening calculations based on simulation techniques. The measured broadening, shift, and asymmetry parameters are also compared with results of previous Stark broadening calculations and other experimental data obtained at electron densities higher as well as lower than ours.