Radiative energy loss in a two-temperature argon plasma

We have calculated the total radiative loss in an argon plasma at wavelengths from 100 nm to 100 µm (zero absorption) as a function of temperature (3000–15,000 K) for several pressures (10-1 × 106Pa) under LTE and non-LTE conditions. The investigated non-equilibrium aspects are deviations of the neutral ground state population with respect to the equilibrium population (partial LTE). A difference between heavy particle and electron temperature is included. When the calculated total radiative loss is divided by the square of the electron density, a curve is obtained which gives the total radiative loss as a function of temperature. The influences of pressure and deviations from LTE on this curve are small and in many cases negligible. Almost all influences of pressure and deviations from equilibrium are incorporated in the electron density. Absolute measurements in an inductively-coupled plasma can be simulated with realistic values of the b factor (Boltzmann decrement).