Measurement of the inhomogeneity of the KATRIN tritium source electric potential by high-resolution spectroscopy of conversion electrons from ${}^{83m}$Kr

Abstract

Precision spectroscopy of the electron spectrum of the tritium $\beta$-decay near the kinematic endpoint is a direct method to determine the effective electron antineutrino mass. The KArlsruhe TRItium Neutrino (KATRIN) experiment aims to determine this quantity with a sensitivity of better than 0.3eV (90% C.L.). An inhomogeneous electric potential in the tritium source of KATRIN can lead to distortions of the $\beta$-spectrum, which directly impact the neutrino-mass observable. This effect can be quantified through precision spectroscopy of the conversion-electrons of co-circulated metastable ${}^{83m}$Kr. Therefore, dedicated, several-weeks long measurement campaigns have been performed within the KATRIN data taking schedule. In this work, we infer the tritium source potential observables from these measurements, and present their implications for the neutrino-mass determination.

References in corpus (7)

• Direct Measurements of Neutrino Mass
• The Design, Construction, and Commissioning of the KATRIN Experiment
• Focal-plane detector system for the KATRIN experiment
• Neutral tritium gas reduction in the KATRIN differential pumping sections
• Wideband precision stabilization of the -18.6 kV retarding voltage for the KATRIN spectrometer
• Operation Modes of the KATRIN Experiment Tritium Loop System using ${}^{83\mathrm{m}}$Kr
• Using krypton-83m to determine the neutrino-mass bias caused by a non-constant electric potential of the KATRIN source