Magnetic Field Inhomogeneities and Their Influence on Transmission and Background at the KATRIN Main Spectrometer

The goal of the KATRIN experiment is to measure the absolute mass of the electron-antineutrino with a sensitivity of 200 meV by analyzing the shape of the tritium-beta-decay energy spectrum. The energy analysis is done with a large scale MAC-E filter (magnetic adiabatic collimation and electrostatic filter) with a magnetic field of 0.3 mT in the analyzing plane. This work investigates small disturbances of the magnetic field influencing the transmission and background properties of the setup