On the line shift and oscillator strength of Xe II lines in the spectra of HnMn stars
Aims. The ultimate goal that has motivated this work is to achieve realistic oscillator strength (<i>gf</i>) values to find reliable values of stellar abundances. We aim to compare the <i>gf</i> valúes of Xe ii lines found with different theoretical and experimental methods....
| Authors: | , , |
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| Format: | article |
| Status: | Published version |
| Publication Date: | 2015 |
| Country: | Argentina |
| Institution: | Universidad Nacional de La Plata |
| Repository: | SEDICI (UNLP) |
| Language: | English |
| OAI Identifier: | oai:sedici.unlp.edu.ar:10915/86392 |
| Online Access: | http://sedici.unlp.edu.ar/handle/10915/86392 |
| Access Level: | Open access |
| Keyword: | Ciencias Astronómicas Atomic data Line: identification Stars: abundances Stars: chemically peculiar |
| Summary: | Aims. The ultimate goal that has motivated this work is to achieve realistic oscillator strength (<i>gf</i>) values to find reliable values of stellar abundances. We aim to compare the <i>gf</i> valúes of Xe ii lines found with different theoretical and experimental methods. Methods. We have undertaken calculations using the quasirelativistic and relativistic Hartree-Fock methods. Then we compare these results with those previously obtained from UVES spectra of HgMn stars. Results. 1) Our theoretical <i>gf</i> values are more realistic than those previously obtained for most lines. When we consider only unblended, isolated, relatively noise-free lines, however, our theoretical <i>gf</i> values and Yuce's stellar values differ little from each other. 2) In a discussion of the origin of the previously observed discrepancy between the wavelengths of Xe ii lines deducted from stellar spectra and those published by National Institute of Standards and Technology (NIST), we conclude that stellar wavelengths could be considered the standard wavelengths whenever the densities in stellar atmospheres are smaller than 1 × 10<SUP>16</SUP> part. cm<SUP>-3</SUP>. |
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