Transition probabilities and continuum emission coefficients in an argon arc plasma

Results are presented for the experimentally determined transition probabilities for the Ar I line at 430 nm and the Ar II line at 480.6 nm using both pure argon diagnostics and H beta electron density diagnostics applied to a wall-stabilised arbon arc LTE plasma. Full profile fitting of H beta at N c approximately=2*10 23 m -3 using the Stark-broadening data of Griem (1974) yields electron densities approximately 11% lower than the data of Vidal et al. (1973), the latter being within 2% of the pure argon diagnostic value. Using the pure argon diagnostics, the transition probabilities are: Ar I at 430 nm, A ki =0.372*10 6 s -1 ; Ar II at 480.6 nm, A ki =74.9*10 6 s -1 . Continuum emission coefficients are also given at 431.4 and 482.7 nm.