Stark-broadened hydrogen line profiles predicted by the model microfield method for calculating electron number densities

This report is the first account on the application of theoretical Stark-br oadening profiles predicted by the model microfield method (MMM) to estimat e electron number density (n(e)) in several laboratory plasmas. The determi nation of n(e) is accomplished by least-squares fitting of the entire emiss ion profile or the wing portions of the emission profile of the H-beta line (486.13 nm) to the theoretical Stark-broadened profiles. Experimental prof iles obtained for the H-beta line from argon and helium inductively coupled plasmas (ICP), a glow discharge, and a high-voltage spark are used to test the new MMM profiles. Results are contrasted with data predicted by the tr aditional 'Unified Theory'. Compared to the 'Unified Theory', the MMM profi les are more accurate in the line center and span over a wide range of temp erature (2500-80000 K) and electron number densities (1 x 10(10)-1 x 10(17) cm(-3)). (C) 2001 Elsevier Science B.V. All rights reserved.