The KATRIN experiment aims to determine the neutrino mass scale with a sensitivity of 200 meV/c2
The KArlsruhe Tritium Neutrino experiment KATRIN [1] aims to measure an ‘effective mass’ of the electron anti-neutrino, given by an incoherent sum over the mass eigenstates [2]. It performs kinematic measurements of tritium β
The outline of the KATRIN experiment is depicted in Fig. 1 [1, 2]. Molecular tritium is fed into the 10m long beam tube of the windowless gaseous tritium source (WGTS [6]). Superconducting magnets along the beam line create an adiabatic guiding field in a 191Tcm2
A precise knowledge of the transmission properties of the KATRIN main spectrometer is crucial to limit systematic uncertainties and reach the desired neutrino mass sensitivity. The transmission properties are affected by inhomogeneities of the electromagnetic fields in the main spectrometer. In addition to simulations, dedicated measurements are necessary to determine the spectrometer transmission function over the complete magnetic flux tube. Such measurements require a mono-energetic and angular-selective electron source, which we present in this work. A pulsed electron beam allows us to access additional information from the electron time-of-flight (ToF) [19].
