Item

Abstract

The ECHo and Holmes experiments investigate the effective electron neutrino mass following the least model-dependent approach by studying the kinematic of the electron capture in ¹⁶³Ho using cryogenic microcalorimeters. Possible systematic shifts in the calorimetric measurements can originate from the decay of ¹⁶³Ho within the solid gold absorber material of the calorimeter. In order to assess if such a systematic shift is present on the current sensitivity level of those experiments, the Q-value of this decay from microcalorimetry is compared to an independently measured one. This cumulative thesis is based on the experimental developments towards and the independent measurement of the Q-value of ¹⁶³Ho electron capture using Penning-trap mass spectrometry. In the first part of this thesis, an injection system for an electron beam ion trap capable of operating with rare isotopes, specifically the artificially produced ¹⁶³Ho, was developed for the creation of highly charged ions. For the Penningtrap measurement, a single highly charged ion in the correct charge state is required and has to be selected from the different charge states produced within in the electron beam ion trap. A Bradbury-Nielsen gate and a very fast high-voltage push-pull switch based on silicon carbide MOSFETs was developed within this thesis to separate the different charge states according to their time-of-flight in the beamline following the electron beam ion trap. These technical developments allowed a measurement of the Q-value of ¹⁶³Ho with the Penning-trap mass spectrometer Pentatrap as the main result of this thesis.