eprintid: 20759
rev_number: 12
eprint_status: archive
userid: 2520
dir: disk0/00/02/07/59
datestamp: 2016-06-01 07:42:27
lastmod: 2016-06-17 12:05:42
status_changed: 2016-06-01 07:42:27
type: doctoralThesis
metadata_visibility: show
creators_name: Bekker, Hendrik
title: Optical and EUV spectroscopy of highly charged ions near the 4f–5s level crossing
subjects: ddc-500
subjects: ddc-530
divisions: i-130200
adv_faculty: af-13
abstract: In recent years, various highly charged ions (HCI) with optical transitions have been proposed for metrology and searches of a possible variation of the fine-structure constant α. Optical transitions in HCI are uncommon due to the scaling of energy levels with atomic number Z^2 . At the 4f–5s level crossing, three configurations are nearly degenerate, and thus many optical transitions can exist. The complex many-electron couplings reduce the accuracy of
current calculations. Moreover, experimental data to benchmark the predictions is lacking. Spectra in the optical and extreme-ultraviolet (EUV) range of several ion species near the 4f–5s level crossing were measured at the Heidelberg electron beam ion trap. A collisional-radiative model was employed for the interpretation of the EUV data, resulting in the first identification of the long sought-after 5s–5p transitions in Pm-like Re^14+ , Os^15+ , Ir^16+ , and
Pt^17+. The characteristic line shapes of optical transitions in Ir17+ were studied, with the aim of identifying transitions with a high sensitivity to α-variation. Previously suggested candidates could be excluded and new candidates were proposed. This data provides a stringent benchmark for state-of-the-art precision atomic theory.
date: 2016
id_scheme: DOI
id_number: 10.11588/heidok.00020759
ppn_swb: 1657186415
own_urn: urn:nbn:de:bsz:16-heidok-207590
date_accepted: 2016-05-18
advisor: HASH(0x561a6291e480)
language: eng
bibsort: BEKKERHENDOPTICALAND2016
full_text_status: public
citation:   Bekker, Hendrik  (2016) Optical and EUV spectroscopy of highly charged ions near the 4f–5s level crossing.  [Dissertation]     
document_url: https://archiv.ub.uni-heidelberg.de/volltextserver/20759/1/HendrikBekker_PhD-thesis_160403_final.pdf