Untersuchungen zum Existenzbereich einer BOLTZMANN‐Verteilung im Argonbogenplasma

Using as plasma source a wall stabilized argon arc working within a restricted parameter range (inner tube diameter = 7 mm, pressure = 30–120 Torr, current = 5‐20 A)) the existence of a Boltzmann equilibrium between spectral energy levels is checked by comparing measured occupation number densities of higher excited levels ( N m, exp ) with the corresponding number densities calculated under the assumption of Boltzmann equilibrium ( N m, calc ). The methods for determination of the quantities N m, exp' T g (2300–5405°K), T e (7170–9950°K) and N e (0.33 – 2.4 × 10 15 cm −3 ) needed for this comparison are described. It can be shown within the limit of experimental error that a Boltzmann equilibrium exists at least for electron densities of N e > 3 · 10 14 cm −3 . The problem of energy balance of that type of arcs used in these experiments is discussed.