Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
RECOMBINATION RATE COEFFICIENTS OF BORON-LIKE Ne
Stockholm University, Faculty of Science, Department of Physics.
Stockholm University, Faculty of Science, Department of Physics.
Stockholm University, Faculty of Science, Department of Physics.
Show others and affiliations
2013 (English)In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 771, no 2, 78- p.Article in journal (Refereed) Published
Abstract [en]

Recombination of Ne5+ was measured in a merged-beam type experiment at the heavy-ion storage ring CRYRING. In the collision energy range 0-110 eV resonances due to 2s(2)2p -> 2s2p(2) (Delta n=0) and 2s(2)2p -> 2s(2)3l (Delta n=1), core excitations were observed. The experimentally derived rate coefficients agree well with the calculations obtained using AUTOSTRUCTURE. At low energies, recombination is dominated by resonances belonging to the spin-forbidden 2s2p(2)(P-4(J))nl series. The energy-dependent rate coefficients were convoluted with a Maxwell-Boltzmann electron energy distribution to obtain plasma recombination rate coefficients. The data from the literature deviate from the measured results at low temperature.

Place, publisher, year, edition, pages
2013. Vol. 771, no 2, 78- p.
Keyword [en]
atomic data, atomic processes, plasmas
National Category
Physical Sciences
Research subject
Physics
Identifiers
URN: urn:nbn:se:su:diva-92764DOI: 10.1088/0004-637X/771/2/78ISI: 000321340700003OAI: oai:DiVA.org:su-92764DiVA: diva2:641964
Note

AuthorCount:7;

Available from: 2013-08-20 Created: 2013-08-20 Last updated: 2017-12-06Bibliographically approved
In thesis
1. Electron - Ion Recombination Data for Plasma Applications: Results from Electron Beam Ion Trap and Ion Storage Ring
Open this publication in new window or tab >>Electron - Ion Recombination Data for Plasma Applications: Results from Electron Beam Ion Trap and Ion Storage Ring
2012 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

This thesis contains results of electron-ion recombination processes in atomic ions relevant for plasma applications. The measurements were performed at the Stockholm Refrigerated Electron Beam Ion Trap (R-EBIT) and at the CRYRING heavy-ion storage ring. Dielectronic recombination (DR) cross sections, resonant strengths, rate coefficients and energy peak positions in H-like and He-like S are obtained for the first time from the EBIT measurements. Furthermore, the experimentally obtained DR resonant strengths are used to check the behaviour of a scaling formula for low Z, H-and He-like iso-electronic sequences and to update the fitting parameters. KLL DR peak positions for initially He- to B-like Ar ions are obtained experimentally from the EBIT measurements. Both the results from highly charged sulfur and argon are compared with the calculations performed with a distorted wave approximation.

Absolute recombination rate coefficients of B-like C, B-like Ne and Be-like F ions are obtained for the first time with high energy resolution from storage ring measurements. The experimental results are compared with the intermediate coupling AUTOSTRUCTURE calculations. Plasma rate coefficients of each of these ions are obtained by convoluting the energy dependent recombination spectra with a Maxwell-Boltzmann energy distribution in the temperature range of 103-106 K. The resulting plasma rate coefficients are presented and compared with the calculated data available in literature.

Place, publisher, year, edition, pages
Stockholm: Department of Physics, Stockholm University, 2012. 64 p.
Keyword
Highly charged ions, Atomic processes, Atomic data, Electron-ion recombination, Plasmas
National Category
Physical Sciences Atom and Molecular Physics and Optics
Research subject
Physics
Identifiers
urn:nbn:se:su:diva-75311 (URN)978-91-7447-497-8 (ISBN)
Public defence
2012-05-14, sal FA31, AlbaNova universitetscentrum, Roslagstullsbacken 21, Stockholm, 10:00 (English)
Opponent
Supervisors
Note

At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 4: Accepted. Paper 5: Accepted. Paper 6: Manuscript. Paper 7: Manuscript.

Available from: 2012-04-22 Created: 2012-04-14 Last updated: 2013-08-20Bibliographically approved
2. Interaction of atomic ions with electrons: Recombination rate coefficients for C1+, F5+, Ne5+, S14+,S15+
Open this publication in new window or tab >>Interaction of atomic ions with electrons: Recombination rate coefficients for C1+, F5+, Ne5+, S14+,S15+
2012 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

This thesis concentrates on electron-ion interaction studies, in particular focusing on dielectronic recombination (DR) of highly charged ions relevant to astrophysics and plasma physics. The measurements were performed at the Stockholm Refrigerated Electron Beam Ion Trap (R-EBIT) and at the CRYRING heavy-ion storage ring. For the R-EBIT measurements a newly developed time-of-flight (TOF) technique for separation of ions and detecting the charge state distribution was utilized. By using ion intensities derived from the TOF spectra as input parameters in the rate equations, energy dependent DR rate coefficients for S15+ and S14+ ions were obtained for the first time. Resonance energies and cross sections calculated within the relativistic many-body perturbation theory for S15+ agree well with the experimental data. In addition to the TOF spectra, the x-ray spectra have been also collected. The combination of these two measurements allows us to separate the photo-recombination and the excitation spectra, from which the excitation rate coefficients for S15+ and S14+ ions were extracted.

From the storage ring measurements absolute recombination rate coefficients for C1+, F5+, and Ne5+ions as a function of electron-ion collision energy were obtained. These were reported for the first time with high energy resolution. The experimental results were compared with results obtained from AUTOSTRUCTURE calculations. Temperature dependent rate coefficients have been also derived for the studied ions and compared with calculations available in the literature.

Place, publisher, year, edition, pages
Stockholm: Department of Physics, Stockholm University, 2012. 71 p.
National Category
Atom and Molecular Physics and Optics
Research subject
Physics
Identifiers
urn:nbn:se:su:diva-75912 (URN)978-91-7447-529-6 (ISBN)
Public defence
2012-06-11, FB41, AlbaNova universitetscentrum, Roslagstullsbacken 21, Stockholm, 14:00 (English)
Opponent
Supervisors
Note

At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: Accepted. Paper 5: Manuscript. Paper 6: Accepted. Paper 7: Manuscript.

Available from: 2012-05-10 Created: 2012-05-03 Last updated: 2013-08-20Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text

Search in DiVA

By author/editor
Mahmood, SultanOrban, IstvanAli, SafdarSchuch, Reinhold
By organisation
Department of Physics
In the same journal
Astrophysical Journal
Physical Sciences

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 57 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf