title: Measurement of a high energy resolution and high  statistics 163Ho electron capture spectrum for the  ECHo experiment
creator: Velte, Clemens
subject: 530
subject: 530 Physics
description: The goal of the ECHo collaboration is to reach a sub-eV sensitivity on the effective  electron neutrino mass by the analysis of the high energy resolution and high  statistics 163Ho electron capture spectrum measured with metallic magnetic micro  calorimeters. Within this thesis several measurements have been performed for detector  optimization and for a study of the spectral shape of the 163Ho . In a first  measurement the heat capacity of Ho-ions implanted in gold absorbers was measured.  It was found that an implanted activity per pixel of a = 10 Bq does not  compromise in a noticeable way the performance of the detector at T = 20 mK. To  test the performance of MMC detectors shielded by rock and to check this option  of operation for future ECHo phases, an experiment was performed in an underground  lab. This measurement allowed for the first time a detailed investigation  of the 163Ho spectral shape. Furthermore, was a first high statistic 163Ho spectrum  acquired. The analysis allows for a determination of the Q-value of the 163Ho EC  with Q = 2.837 +- 0.005 (stat) +- 0.005 (syst) keV and to perform a first analysis of the end  point region of the spectrum to extract an effective electron neutrino mass.
date: 2020
type: Dissertation
type: info:eu-repo/semantics/doctoralThesis
type: NonPeerReviewed
format: application/pdf
identifier: https://archiv.ub.uni-heidelberg.de/volltextserverhttps://archiv.ub.uni-heidelberg.de/volltextserver/27340/1/Dissertation.pdf
identifier: DOI:10.11588/heidok.00027340
identifier: urn:nbn:de:bsz:16-heidok-273401
identifier:   Velte, Clemens  (2020) Measurement of a high energy resolution and high statistics 163Ho electron capture spectrum for the ECHo experiment.  [Dissertation]     
relation: https://archiv.ub.uni-heidelberg.de/volltextserver/27340/
rights: info:eu-repo/semantics/openAccess
rights: http://archiv.ub.uni-heidelberg.de/volltextserver/help/license_urhg.html
language: eng