Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Observing and modeling the dynamic atmosphere of the low mass-loss
  C-star R Sculptoris at high angular resolution   We study the circumstellar environment of the carbon-rich star R Scl using
the near- and mid-infrared high spatial resolution observations from the
ESO-VLTI instruments VINCI and MIDI. These observations aim at increasing our
knowledge of the dynamic processes in play within the very close circumstellar
environment where the mass loss of AGB stars is initiated. Data are interpreted
using a self-consistent dynamic model. Interferometric observations do not show
any significant variability effect at the 16 m baseline between phases 0.17 and
0.23 in the K band, and for both the 15 m baseline between phases 0.66 and 0.97
and the 31 m baseline between phases 0.90 and 0.97 in the N band. We find
fairly good agreement between the dynamic model and the spectrophotometric data
from 0.4 to 25 $\mu$m. The model agrees well with the time-dependent flux data
at 8.5 $\mu$m, whereas it is too faint at 11.3 and 12.5 $\mu$m. The VINCI
visibilities are reproduced well, meaning that the extension of the model is
suitable in the K-band. In the mid-infrared, the model has the proper extension
to reveal molecular structures of C2H2 and HCN located above the stellar
photosphere. However, the windless model used is not able to reproduce the more
extended and dense dusty environment. Among the different explanations for the
discrepancy between the model and the measurements, the strong nonequilibrium
process of dust formation is one of the most probable. The complete dynamic
coupling of gas and dust and the approximation of grain opacities with the
small-particle limit in the dynamic calculation could also contribute to the
difference between the model and the data.

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The categories of this paper are: hep-ph
34
The categories of this paper are: chem-ph
19
The categories of this paper are: eess
3
The categories of this paper are: physics
18
The categories of this paper are: econ
26
The categories of this paper are: bayes-an
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The categories of this paper are: cs
27
The categories of this paper are: comp-gas
17
The categories of this paper are: q-fin
35
The categories of this paper are: mtrl-th
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The categories of this paper are: cond-mat
21
The categories of this paper are: adap-org
10
The categories of this paper are: q-bio
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The categories of this paper are: math-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: plasm-ph