Tritium source systematics of the KArlsruhe TRItium Neutrino (KATRIN) Experiment(pdf)
KATRIN will perform a direct, kinematics-based measurement of the neutrino mass with a sensitivity of 200 meV (90 % C. L.). The neutrino mass is obtained by determining the shape of the spectrum of tritium β decay electrons close to the endpoint of 18.6 keV with a spectrometer of MAC-E filter type. To achieve the planned sensitivity, the systematic measurement uncertainties have to be carefully controlled and evaluated. Main sources of systematics are the MAC-E filter on the one hand and the windowless gaseous tritium source (WGTS) on the other hand. This talk will focus on the systematics of the WGTS. The WGTS is a 16 m long cryostat operated at 30 K. Most of the operational parameters of the WGTS have to be stable at or even below the per mille level and have to meet further strict requirements. This presentation will give an overview of WGTS systematics and will discuss their individual impact on the neutrino mass determination.