Henrik Hartman
Researcher (Leave of Absence)
The FERRUM project: metastable lifetimes in Cr II
Author
Summary, in English
Parity forbidden radiative transitions from metastable levels are observed in spectra of low-density astrophysical plasmas. These lines are used as probes of the physical conditions, made possible due to the long lifetime of their upper level. In a joint effort, the FERRUM project aims to obtain new and accurate atomic data for the iron-group elements, and part of this project concerns forbidden lines. The radiative lifetimes of the metastable energy levels 3 d4(a 3 D)4 s c4 D 5/2 and 3 d4(a 3 D)4 s c4 D 7/2 of singly ionized chromium have been measured. The experiment has been performed at the ion storage ring CRYRING. We employed a laser-probing technique developed for measuring long lifetimes. In this article, we present the lifetimes of these levels to be t5/2= 1.28(16) s and t7/2= 1.37(7) s, respectively. A comparison with previous theoretical work shows good agreement and the result is discussed in a theoretical context.
Department/s
- Lund Observatory - Undergoing reorganization
Publishing year
2012
Language
English
Pages
1636-1639
Publication/Series
Monthly Notices of the Royal Astronomical Society
Volume
420
Issue
2
Full text
- Available as PDF - 243 kB
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Links
Document type
Journal article
Publisher
Oxford University Press
Topic
- Astronomy, Astrophysics and Cosmology
Keywords
- atomic data
- methods: laboratory
- techniques: spectroscopic
- astronomical data bases: miscellaneous
Status
Published
ISBN/ISSN/Other
- ISSN: 1365-2966