Sprecher
Beschreibung
The KArlsruhe TRItium Neutrino (KATRIN) experiment measures the effective electron antineutrino mass by precision spectroscopy of the endpoint region of the kinematic tritium β-decay spectrum. Using a high-luminosity gaseous molecular tritium source with an electrostatic spectrometer with magnetic adiabatic collimation, an upper limit of 0.45 eV/c² (90% C.L.) on the neutrino mass is currently set by KATRIN, using the first 25% of the total dataset. For the upcoming analysis of the final data set, corresponding to 1000 days of data taking and thus strongly enhanced statistics, a very precise knowledge of all systematic effects is essential. The dominant systematic contributions are source-related: The energy loss due to inelastic scatterings in the source and the gas density. This talk focuses on calibration measurements and methods to determine source-related systematic contributions with the monoenergetic angular-selective photoelectron source (arXiv: 2603.15918).