Experimental studies of the wing broadening of theD _β line

Abstract

The profiles of theD _β line from a homogeneous high density deuterium plasma (electron density ≈10¹⁷ cm⁻³) generated in aT-tube, have been investigated over a wavelength range of ±300 Å from the line centre. After correcting for the contributions from the underlying continuum and from the adjoiningD _β line, the observed profiles in the main body of the line are in close agreement with the corresponding theoretical Stark profiles. In the line wings on the other hand, the observed intensities are consistently higher than those predicted by the various asymptotic wing formulae. It is shown that this discrepancy may be resolved and close agreement obtained in all cases with a minor empirical correction to the wing formulae. The corrections resulting from adopting this procedure for the Ly-α line is briefly discussed.