title: Precision Mass and Mass-Ratio Measurements of Neon and Ytterbium Isotopes for Tests of Fundamental Physics
creator: Door, Menno
subject: ddc-530
subject: 530 Physics
description: During the research for this thesis, several mass ratios were measured with a relative uncertainty of a few  parts per trillion using the cryogenic Penning trap mass spectrometer Pentatrap. The determination  of the mass ratio of the 20Ne isotope against the 12C isotope reached a relative uncertainty of 4×10−12  and, with a deviation of 4 standard deviations to the former literature value, results in the most precise  mass measurement in atomic mass units to date and an improvement of this mass value by a factor of  nineteen. This precision mass determination is used in a test of the theory of quantum electrodynamics  (QED), especially confirming one- and two-loop corrections of bound-state QED at highest precision.  The determination of mass ratios between the five stable even ytterbium isotopes reached a precision of  also 4×10−12. These mass ratios are used in a King plot analysis of isotope shifts in atomic transitions to  exclude the existence of a proposed new boson mediating a new 5th force. The measurements improve  the respective mass ratios determined from literature masses by one to two orders of magnitude. Lastly,  the binding energies of the valence electrons in 172Yb41+ and 172Yb42+ are determined to sub-eV  precision as a cross-check of the measurement accuracy and a test of the theoretical models and  methods used to calculate these binding energies.    The presented cyclotron frequency determinations show an improvement of at least a factor of two  compared to previous measurements of isotope mass ratios at Pentatrap and an improvement of a  factor of six in the determination of binding energies of highly charged ions, made possible by an upgrade  of the experiments detection system within this thesis. The measurement of the mass of 20Ne was the  first measurement of light ions and the first measurement against the atomic mass unit reference 12C  at this experiment, and, with the precision demonstrated, paves the way for further high-precision mass  determinations in atomic mass units in this experiment. The presented accuracy of binding energy determinations  will enable stringent tests of QED-theory in the future by determining the binding energies  of electrons in heavier atoms and higher charge states.
date: 2024
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/35208/1/thesis_door.pdf
identifier: DOI:10.11588/heidok.00035208
identifier: urn:nbn:de:bsz:16-heidok-352080
identifier:   Door, Menno  (2024) Precision Mass and Mass-Ratio Measurements of Neon and Ytterbium Isotopes for Tests of Fundamental Physics.  [Dissertation]     
relation: https://archiv.ub.uni-heidelberg.de/volltextserver/35208/
rights: info:eu-repo/semantics/openAccess
rights: Please see front page of the work (Sorry, Dublin Core plugin does not recognise license id)
language: eng