Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: NLTE analysis of Sr lines in spectra of late-type stars with new
  R-matrix atomic data   We investigate statistical equilibrium of neutral and singly-ionized
strontium in late-type stellar atmospheres. Particular attention is given to
the completeness of the model atom, which includes new energy levels,
transition probabilities, photoionization and electron-impact excitation
cross-sections computed with the R-matrix method. The NLTE model is applied to
the analysis of Sr I and Sr II lines in the spectra of the Sun, Procyon,
Arcturus, and HD 122563, showing a significant improvement in the ionization
balance compared to LTE line formation calculations, which predict abundance
discrepancies of up to 0.5 dex. The solar Sr abundance is log A = 2.93 \pm 0.04
dex, in agreement with the meteorites. A grid of NLTE abundance corrections for
Sr I and Sr II lines covering a large range of stellar parameters is presented.

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The categories of this paper are: physics
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The categories of this paper are: quant-ph
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The categories of this paper are: stat
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The categories of this paper are: hep-lat
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The categories of this paper are: atom-ph
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The categories of this paper are: hep-th
9
The categories of this paper are: nlin
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The categories of this paper are: nucl-ex
10
The categories of this paper are: q-bio
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The categories of this paper are: eess
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The categories of this paper are: chao-dyn
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The categories of this paper are: math-ph
30
The categories of this paper are: q-alg
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The categories of this paper are: bayes-an
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The categories of this paper are: funct-an
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The categories of this paper are: hep-ex