SMuK 2023 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
P: Fachverband Plasmaphysik
P 15: Laser Plasmas II/Low Pressure Plasmas and their Applications II
P 15.4: Vortrag
Donnerstag, 23. März 2023, 15:00–15:15, CHE/0089
Collisional radiative modelling for molecular hydrogen plasmas applying MCCC cross sections — •Richard Christian Bergmayr, Dirk Wünderlich, and Ursel Fantz — Max-Planck-Institut für Plasmaphysik, Garching, Germany
Molecular hydrogen (H2) occurs in a variety of plasmas (e.g. negative ion source and fusion divertor plasmas). Collisional radiative (CR) models enable the characterization of these plasmas not only by their plasma parameters in combination with emission spectroscopy, but also to evaluate effective reaction rates (e.g. for molecular assisted recombination (MAR), a mechanism that may contribute to the detachment in divertors). CR models balance (de-)populating mechanisms of excited states in terms of coupled rate equations. Recent studies using a CR model for the triplet system of H2 have shown that applying electron impact excitation cross sections calculated by the molecular convergent close-coupling (MCCC) method in the adiabatic-nuclei formulation show an improved agreement with measurements in low-pressure plasmas compared to models based on previously available cross sections. In this work a CR model for the electronic states of the singlet system of H2 applying MCCC cross sections is presented showing likewise as the triplet model better agreement with measurements than previous models. Furthermore, the models for the singlet and triplet system are coupled. Thereby it is possible to estimate also the influence of (optically forbidden) spin-mixing processes. In a next step this knowledge can be used to create a (ro-)vibrationally resolved model for H2, as (ro-)vibrational excitation is expected to enhance MAR.