Background Reduction Methods and Vacuum Technology at the KATRIN Spectrometers

The goal of KATRIN 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. To minimize the background due to residual gas ionization, a pressure in the lower 10E-11 mbar region is required. This work focuses on the applied vacuum technology. In addition a system of LN2 cooled baffles was designed that eliminates radon-induced background, which is essential for a neutrino mass measurement