SMuK 2023 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

P: Fachverband Plasmaphysik

P 20: Laser Plasmas III/Codes and Modeling III

P 20.4: Vortrag

Donnerstag, 23. März 2023, 18:30–18:45, CHE/0091

1D Vlasov simulations of the Windowless Gaseous Tritium source of the Karlsruhe Tritium Neutrino experiment — •Anna Josephine Schulze and Felix Spanier — University of Heidelberg

The aim of the Karlsruhe Tritium Neutrino (KATRIN) experiment is to precisely determine the neutrino mass by measuring the electron energy spectrum of the tritium-beta-decay. The high energy of this decay is also the reason for a plasma to develop inside the windowless gaseous tritium source (WGTS). Interactions between the plasma and metallic walls lead to the formation of a plasma sheath and with it an electrostatic potential arises. This can modify the resulting energy spectrum. Therefore, the behaviour of the plasma and especially its wall-interaction was estimated using a 1D simulation. It is based on solving the Vlasov-Poisson system with an Eulerian scheme to compute the electric potential along the middle axis of the tritium source. This technique allows for stronger density gradients as well as atomic processes to be considered. In general, however, it is more computationally expensive than a particle-in-cell method. Initial results yield a plasma potential of Δ φ = 0.047 V and show a backflow of electrons, leading to the development of a two-stream instability in the plasma. Currently, the code is further developed to simulate a larger area of the WGTS and to consider more effects, including recombination.