2020/11/10 by F. M. Fränkle, Fränkle, F. M., Schaller, A. +35 · 1 voice · 1 citation
Physics and Astronomy · #Dark Matter and Cosmic Phenomena #FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #Instrumentation and Detectors (physics.ins-det) #Neutrino Physics Research #Nuclear physics research studies
paper · pdf · doi:10.48550/arxiv.2011.05107
openalex publication_date 2020/11/10 · openalex created_date 2020/11/23 · openalex updated_date 2026/07/28
The goal of the KArlsruhe TRItrium Neutrino (KATRIN) experiment is the determination of the effective electron antineutrino mass with a sensitivity of 0.2 eV/c2 at 90% C.L. This goal can only be achieved with a very low background level in the order of 0.01 counts per second. A possible background source is α-decays on the inner surface of the KATRIN Main Spectrometer. Two α-sources, 223Ra and 228Th, were installed at the KATRIN Main Spectrometer with the purpose of temporarily increasing the background in order to study α-decay induced background processes. In this paper, we present a possible background generation mechanism and measurements performed with these two radioactive sources. Our results show a clear correlation between α-activity on the inner spectrometer surface and background from the volume of the spectrometer. Two key characteristics of the Main Spectrometer background -the dependency on the inner electrode offset potential, and the radial distribution - could be reproduced with this artificially induced background. These findings indicate a high contribution of α-decay induced events to the residual KATRIN background.