Mainz 2014 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
T: Fachverband Teilchenphysik
T 89: Niederenergie-Neutrinophysik 4
T 89.4: Talk
Wednesday, March 26, 2014, 17:35–17:50, P106
Removal of Stored Electrons in the KATRIN Main Spectrometer — •Daniel Hilk for the KATRIN collaboration — Institut für Experimentelle Kernphysik, KIT, Karlsruhe
The goal of the KATRIN experiment is to determine the effective mass of the electron anti neutrino by measuring the electron energy spectrum of the tritium beta decay near the endpoint. The goal is to reach a sensitivity of the neutrino mass of 200meV for which an ultra-low background level of 10−2 counts per second is mandatory. Electrons from single radioactive decays of radon and tritium in the KATRIN main spectrometer can be stored for hours. While cooling down via ionization of residual gas molecules, they produce hundreds of secondary electrons, which can reach the detector and contribute to the background signals. In order to suppress this background component, several methods are investigated to remove stored electrons, such as the application of an electric dipole field and the application of magnetic pulses. This talk introduces the theory of background production mechanisms due to stored electrons and the removal by active methods in the main spectrometer. In context of the spectrometer- and detector-commissioning phase in summer 2013, measurement results of the application of the electric dipole- and magnetic pulse-method are presented. This work was supported by the BMBF under grant no. 05A11VK3 and by the Helmholtz Association.