ABSTRACT
SPECTROSCOPIC INVESTIGATIONS The plasma properties of mercury-free Na/Sc lamps are investigated at the 1LPP by means of emission spectroscopy with absolute calibration in the wavelength range between 200 and 833 nm. The experimental set-up includes a spectrometer (f = 1 m) with an attached CCD detector. From the
spectroscopic measurements temperature profiles across the plasma radius are determined by analysis of self-reversed spectral lines based upon the method proposed in [3]. Figure 2 shows a radial temperature distribution of a mercury-free lamp at the centre of the arc. The temperature profiles obtained and the calculated densities of
4000 species serve as input parameters for solving the radiative transfer equation. In addition, radiances of selected atomic spectral lines are compared
3 with model calculations. As a result spectral line
parameters for resonance, Stark and van der Waals broadening are determined. Required particle densities of gaseous species are obtained by means of chemical equilibrium calculations.
