München 2019 – wissenschaftliches Programm
HK 54.52: Poster
Donnerstag, 21. März 2019, 16:30–19:00, Foyer Theresanium
An electroluminescence tracking TPC for high rates — •Markus Ball, Kevin Dojan, Bernhard Ketzer, and Konstantin Muenning — Helmholtz Institut für Strahlen und Kernphysik, Universität Bonn
Time Projection Chambers (TPC) are used both for tracking of charged particles and the search for rare events. The requirements for these two fields of applications are rather different. A high drift velocity, low diffusion and small distortions of the drifting electrons are mandatory for tracking, especially at high rates. Distortions are primarily induced by ions drifting back from the avalanche multiplication region into the drift region. This ion backflow could be completely eliminated by exploiting a different concept for signal amplification based on excitation instead of ionization, i.e. electroluminescence. The excited noble gas atoms form dimers, which emit photons with a gas-specific wavelength, which is typically in the deep UV region. This concept is widely used in rare-event TPCs. We plan to adapt it to develop a zero-ion-backflow tracking TPC for future applications in high-rate experiments. This requires the addition of a quench gas in order to achieve higher drift velocities and limit the diffusion. The quencher, however, also reduces the light yield. The goal is to find a gas mixture, which is suitable for tracking and amplification by electroluminescence. GARFIELD++ simulations provide some guidance, but the final validation has to come from experiment. The poster will present simulation results and a demonstrator setup, which are currently being assembled. This work was supported by BMBF.