Systematics and background suppression in the KATRIN experiment

TL;DR

The KATRIN experiment aims to measure the neutrino mass with unprecedented sensitivity by improving signal rate and background suppression techniques in a scaled-up spectrometer setup.

Contribution

This paper presents systematic methods for background reduction and systematic error control in the KATRIN neutrino mass experiment.

Findings

Achieved a low background rate through active and passive suppression techniques.

Enhanced energy resolution of 0.93 eV in the scaled-up spectrometer.

Projected sensitivity of 0.2 eV/c^2 for neutrino mass measurement.

Abstract

Recent neutrino mass experiments at Mainz and Troitsk using tritium beta-decay have reached their sensitivity potential, yielding upper limits of about 2 eV/c^2 for the electron antineutrino mass. The KArlsruhe TRItium Neutrino experiment (KATRIN), designed to reach a sensitivity of 0.2 eV/c^2 (90% C.L.), will improve the signal rate by a factor of about 100 with respect to previous experiments while maintaining the same low background level at an enhanced energy resolution of 0.93 eV of the spectrometer which is scaled up by a factor of 10 in linear dimensions. This low background rate can only be achieved by active and passive reduction of the background components induced by the spectrometer itself and in the detector region. Furthermore, sources of systematic errors such as energy losses inside the tritium source or fluctuations of the energy scale of the spectrometer need to be carefully controlled and analysed. An overview of KATRIN's method to reduce the background rate and to determine the systematics as well as the sensitivity on the neutrino mass will be presented.