title: High-precision mass measurements of neutron-deficient Tl isotopes at ISOLTRAP and the development of an ultra-stable voltage source for the PENTATRAP experiment
creator: Böhm, Christine
subject: ddc-530
subject: 530 Physics
description: Atomic masses and hence binding energies of nuclides are of great importance for studies of nuclear structure since they reflect all effective interactions in a nucleus.  Within this thesis the masses of seven nuclides, namely 194Au, 194Hg, 190,193,198Tl and 202,208Pb, were determined at the Penning-trap mass spectrometer ISOLTRAP at ISOLDE/CERN.  The thallium region in the chart of isotopes is of special interest due to the occurrence of nuclear structure effects like low-lying isomers, level inversion, shape coexistence  and deformations. These effects are investigated by applying finite-difference mass formulas, such as the two-neutron separation energies or the so-called empirical  pairing gaps. The second topic addressed within the present thesis is an ultra-stable voltage source, called StaReP (Stable Reference for Penning Trap Experiments),  which was developed at the Max-Planck-Institut für Kernphysik. It is one of the  key components of the high-precision mass spectrometer PENTATRAP, containing a tower of five Penning traps. A 25-channel voltage source with a relative stability  of few 10^−8 over a period of 10 minutes in the range of 0 to −100V is mandatory for PENTATRAP aiming for mass measurements with relative mass uncertainties  of ≤ 10^−11. Mass values with such a high precision allow for stringent tests of quantum electrodynamics in strong electric fields, testing Einstein’s mass-energy relation  E = mc^2 as well as measurements of decay energies (Q-values) with applications in neutrino physics.
date: 2015
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/18106/1/Boehm_Diss_pdf_A.pdf
identifier: DOI:10.11588/heidok.00018106
identifier: urn:nbn:de:bsz:16-heidok-181065
identifier:   Böhm, Christine  (2015) High-precision mass measurements of neutron-deficient Tl isotopes at ISOLTRAP and the development of an ultra-stable voltage source for the PENTATRAP experiment.  [Dissertation]     
relation: https://archiv.ub.uni-heidelberg.de/volltextserver/18106/
rights: info:eu-repo/semantics/openAccess
rights: http://archiv.ub.uni-heidelberg.de/volltextserver/help/license_urhg.html
language: eng