English
 
Help Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
 
 
DownloadE-Mail
  Experimental Investigations of Ion Charge Distributions, Effective Electron Densities, and Electron-Ion Cloud Overlap in Electron Beam Ion Trap Plasma Using Extreme-Ultraviolet Spectroscopy

Liang, G. Y., Crespo López-Urrutia, J. R., Baumann, T. M., Epp, S. W., Gonchar, A., Lapierre, A., et al. (2009). Experimental Investigations of Ion Charge Distributions, Effective Electron Densities, and Electron-Ion Cloud Overlap in Electron Beam Ion Trap Plasma Using Extreme-Ultraviolet Spectroscopy. Astrophysical Journal, 702(2), 838-850. doi:10.1088/0004-637X/702/2/838.

Item is

Files

show Files

Locators

show

Creators

show
hide
 Creators:
Liang, G. Y.1, Author           
Crespo López-Urrutia, J. R.1, Author           
Baumann, T. M.1, Author           
Epp, S. W.1, Author           
Gonchar, A.1, Author           
Lapierre, A.1, Author           
Mokler, P. H.1, Author           
Simon, M. C.1, Author           
Tawara, H.1, Author           
Mäckel, V.1, Author           
Yao, K.2, Author
Zhao, G.2, Author
Zou, Y.2, Author
Ullrich, J.1, Author           
Affiliations:
1Division Prof. Dr. Joachim H. Ullrich, MPI for Nuclear Physics, Max Planck Society, ou_904547              
2National Astronomical Observatories, CAS, A20 Datun Road, Chaoyang District, Beijing 100012, China TRIUMF, Canadian National Laboratory for Particle and Nuclear Physics, 4004 Wesbrook Mall, Vancouver, BC V6T 2A3, Canada EBIT Lab, Modern Physics Institute, Fudan University, Shanghai 200433, People's Republic of China Department of Physics, University of Strathclyde, Glasgow G4 0NG, UK, ou_persistent22              

Content

show
hide
Free keywords: line: identification; methods: analytical; methods: laboratory
 Abstract: Spectra in the extreme ultraviolet range from 107 to 353 Å emitted from Fe ions in various ionization stages have been observed at the Heidelberg electron beam ion trap (EBIT) with a flat-field grating spectrometer. A series of transition lines and their intensities have been analyzed and compared with collisional-radiative simulations. The present collisional-radiative model reproduces well the relative line intensities and facilitates line identification of ions produced in the EBIT. The polarization effect on the line intensities resulting from nonthermal unidirectional electron impact was explored and found to be significant (up to 24%) for a few transition lines. Based upon the observed line intensities, relative charge state distributions (CSD) of ions were determined, which peaked at Fe23+ tailing toward lower charge states. Another simulation on ion charge distributions including the ionization and electron capture processes generated CSDs which are in general agreement with the measurements. By observing intensity ratios of specific lines from levels collisionally populated directly from the ground state and those starting from the metastable levels of Fe XXI, Fe X and other ionic states, the effective electron densities were extracted and found to depend on the ionic charge. Furthermore, it was found that the overlap of the ion cloud with the electron beam estimated from the effective electron densities strongly depends on the charge state of the ion considered, i.e. under the same EBIT conditions, higher charge ions show less expansion in the radial direction.

Details

show
hide
Language(s): eng - English
 Dates: 2009-08-17
 Publication Status: Issued
 Pages: -
 Publishing info: -
 Table of Contents: -
 Rev. Type: Peer
 Identifiers: eDoc: 441475
DOI: 10.1088/0004-637X/702/2/838
 Degree: -

Event

show

Legal Case

show

Project information

show

Source 1

show
hide
Title: Astrophysical Journal
  Alternative Title : ApJ
Source Genre: Journal
 Creator(s):
Affiliations:
Publ. Info: -
Pages: - Volume / Issue: 702 (2) Sequence Number: - Start / End Page: 838 - 850 Identifier: -