The radiative production and destruction of atomic states

In recombining plasma of low electron density, the lower part of an atomic energy scheme is completely determined by radiative processes. Atoms of a certain level are produced by decay of atoms of higher bound levels (cascade) or two particle recombination (capture) and destroyed by radiative decay. The kinetics of these radiative processes are discussed as functions of the energy of the level. The authors confine themselves to hydrogenic systems where levels can be `labeled' by their principal quantum number

A scaling rule for molecular electronic transition dipole moments

Guided by the work of Woerdman and Monyakin, we propose rules that allow the electronic transition dipole moment for a transition in one molecule to be determined from that of a similar one in an isovalent species. The rule can be applied to asymptotically allowed and forbidden transitions. We have tested it by applying it in two specific cases: the moments for the A 1X 1 and X 1B 1 transitions in Na2 are found from those in Li2, which are asymptotically allowed and the moments for the BX transition in O2, Se2, and Te2 which are asymptotically forbidden, are found from moment data for S2. Transition moments calculated with this rule are within 15% of the available literature values and behavior as a function of internuclear separation is well described

Power interruption experiments on ICP and MIP

Abstract only. Incompleet

Experimental evidence for the complete saturation phase in the argon neutral system

An experimental study of the population densities of excited states confirms the existence of the complete excitation saturation phase in the argon neutral system. Collisional radiative coefficients r/sub m//sup (1)/ are independent of n/sub e/ and decrease with decreasing ionization energy. At higher n/sub e/-values the levels are observed to come consecutively into Saha equilibrium (PLTE

An analytical excitation for an ionizing plasma

From an analytical model for the population of high-lying excited levels in ionizing plasmas it appears that the distribution is a superposition of the equilibrium (Saha) value and an overpopulation. This overpopulation takes the form of a Maxwell distribution for free electrons. Experiments for He II, Na I and Ar I confirm the general validity of the mode

Numerical simulation of plasma creation and expansion in an argon arc

Abstract only

Radiative transfer in high-current Ar-Hg discharges

Mixtures of noble gases and mercury are widely used in lighting applications, e.g. fluorescent lamps. To optimise the performance of these light sources, numerical modelling has been carried out with the help of PLASIMO, a computer program which is being developed at the Eindhoven University of Technology. The most important process in efficient light sources is also the one which is least understood: the production and transport of resonant radiation. Attempts were made to provide an accurate description of radiative transfer in the plasmas under consideration. Various solutions to the Holstein equation will be presented and discussed. In order to incorporate these solutions into thefluid model PLASIMO, a novel Collisional Radiative Model has been developed. It is discussed in a second contribution to this conference ('Towards a general Collisional Radiative Model, Van Dijk et al.

On the influence of ionization-recombination and radiative losses in thermal plasma modelling

The authors have investigated the influences of the ionization/recombination and the radiative energy loss on the particle and temp. distributions in a pure argon inductively coupled plasma. To calc. the flow and the temp. field an axi-sym. 2-temp. numerical fluid model has been used. Comparisons were made between results obtained by using different types of data for the effective ionization/recombination coeff. and for the radiative energy losses. Exptl. data and a hybrid collisional-radiative model were used for the effective ionization and recombination coeff. For the total radiative loss also exptl. data and a non-local thermal equil. model were applied. With the numerical fluid model it was possible to trace the effects of non-equil. aspects of ionization and recombination on the electron and heavy particle temp. and the electron d. profiles. The electron d. is the most suitable parameter to distinguish the different sets for the ionization/recombination coeff. and the radiative energy loss. [on SciFinder (R)