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On the influence of Stark broadening on Si I lines in stellar atmospheres

M. S. Dimitrijevic·T. Ryabchikova·L. C. Popovic·D. Shulyak·V. Tsymbal
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Abstract

We study the influence of Stark broadening and stratification effects on Siılines in the rapidly oscillating (roAp) star 10 Aql, where the Siı6142.48 Åand 6155.13 Ålines are asymmetrical and shifted. First we have calculated Stark broadening parameters using the semiclassical perturbation method for three Siılines: 5950.2 Å, 6142.48 Åand 6155.13 Å. We revised the synthetic sp$ calculation code taking into account both Stark width and shift for these lines. From the comparison of our calculations with the observations we found that Stark broadening + the stratification effect can explain asymmetry of the Siı6142.48 Åand 6155.13 Ålines in the atmospere of roAp star 10 Aql.

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M. S. Dimitrijevic, T. Ryabchikova, L. C. Popovic, D. Shulyak, V. Tsymbal. 2003-04-22. On the influence of Stark broadening on Si I lines in stellar atmospheres. https://doi.org/10.1051/0004-6361%3A20030561

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