The FERRUM Project: Experimental transition probabilities of [Fe II] and astrophysical applications
(2003) In Astronomy & Astrophysics 397(3). p.11431149 Abstract
 We report on experimental transition probabilities for thirteenforbidden [Fe II] lines originating from three different metastable FeIi levels. Radiative lifetimes have been measured of two metastablestates by applying a laser probing technique on a stored ion beam.Branching ratios for the radiative decay channels, i.e. M1 and E2transitions, are derived from observed intensity ratios of forbiddenlines in astrophysical spectra and compared with theoretical data. Thelifetimes and branching ratios are combined to derive absolutetransition probabilities, Avalues.We present the first experimental lifetime values for the two Fe IIlevels a<SUP>4</SUP>G<SUB>9/2</SUB> and... (More)
 We report on experimental transition probabilities for thirteenforbidden [Fe II] lines originating from three different metastable FeIi levels. Radiative lifetimes have been measured of two metastablestates by applying a laser probing technique on a stored ion beam.Branching ratios for the radiative decay channels, i.e. M1 and E2transitions, are derived from observed intensity ratios of forbiddenlines in astrophysical spectra and compared with theoretical data. Thelifetimes and branching ratios are combined to derive absolutetransition probabilities, Avalues.We present the first experimental lifetime values for the two Fe IIlevels a<SUP>4</SUP>G<SUB>9/2</SUB> and b<SUP>2</SUP>H<SUB>11/2</SUB>and Avalues for 13 forbidden transitions froma<SUP>6</SUP>S<SUB>5/2</SUB>, a<SUP>4</SUP>G<SUB>9/2</SUB> andb<SUP>4</SUP>D<SUB>7/2</SUB> in the optical region. A discrepancybetween the measured and calculated values of the lifetime for theb<SUP>2</SUP>H<SUB>11/2</SUB> level is discussed in terms of levelmixing. We have used the code CIV3 to calculate transitionprobabilities of the a<SUP>6</SUP>Da<SUP>6</SUP>S transitions.We have also studied observational branching ratios for lines from 5other metastable Fe II levels and compared them to calculated values. Aconsistency in the deviation between calibrated observational intensityratios and theoretical branching ratios for lines in a wider wavelengthregion supports the use of [Fe II] lines for determination of reddening. (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/record/130609
 author
 organization
 publishing date
 2003
 type
 Contribution to journal
 publication status
 published
 subject
 keywords
 atomic data, stars: individual: Eta Carinae, ISM: dust, extinction
 in
 Astronomy & Astrophysics
 volume
 397
 issue
 3
 pages
 1143  1149
 publisher
 EDP Sciences
 external identifiers

 wos:000180249800041
 scopus:0037249906
 ISSN
 00046361
 DOI
 10.1051/00046361:20021557
 language
 English
 LU publication?
 yes
 id
 7416faee50c541ea9ec30a405c0087b7 (old id 130609)
 date added to LUP
 20070713 10:41:51
 date last changed
 20180107 09:51:27
@article{7416faee50c541ea9ec30a405c0087b7, abstract = {We report on experimental transition probabilities for thirteenforbidden [Fe II] lines originating from three different metastable FeIi levels. Radiative lifetimes have been measured of two metastablestates by applying a laser probing technique on a stored ion beam.Branching ratios for the radiative decay channels, i.e. M1 and E2transitions, are derived from observed intensity ratios of forbiddenlines in astrophysical spectra and compared with theoretical data. Thelifetimes and branching ratios are combined to derive absolutetransition probabilities, Avalues.We present the first experimental lifetime values for the two Fe IIlevels a<SUP>4</SUP>G<SUB>9/2</SUB> and b<SUP>2</SUP>H<SUB>11/2</SUB>and Avalues for 13 forbidden transitions froma<SUP>6</SUP>S<SUB>5/2</SUB>, a<SUP>4</SUP>G<SUB>9/2</SUB> andb<SUP>4</SUP>D<SUB>7/2</SUB> in the optical region. A discrepancybetween the measured and calculated values of the lifetime for theb<SUP>2</SUP>H<SUB>11/2</SUB> level is discussed in terms of levelmixing. We have used the code CIV3 to calculate transitionprobabilities of the a<SUP>6</SUP>Da<SUP>6</SUP>S transitions.We have also studied observational branching ratios for lines from 5other metastable Fe II levels and compared them to calculated values. Aconsistency in the deviation between calibrated observational intensityratios and theoretical branching ratios for lines in a wider wavelengthregion supports the use of [Fe II] lines for determination of reddening.}, author = {Hartman, Henrik and Derkatch, A. and Donnelly, M. P. and Gull, T. and Hibbert, A. and Johansson, Sveneric and Lundberg, Hans and Mannervik, S and Norlin, L.O. and Rostohar, D. and Royen, P. and Schef, P.}, issn = {00046361}, keyword = {atomic data,stars: individual: Eta Carinae,ISM: dust,extinction}, language = {eng}, number = {3}, pages = {11431149}, publisher = {EDP Sciences}, series = {Astronomy & Astrophysics}, title = {The FERRUM Project: Experimental transition probabilities of [Fe II] and astrophysical applications}, url = {http://dx.doi.org/10.1051/00046361:20021557}, volume = {397}, year = {2003}, }