Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Interpreting the Mg II h and k Line Profiles of Mira Variables   We use radiative transfer calculations to reproduce the basic appearance of
Mg II lines observed from Mira variables. These lines have centroids that are
blueshifted by at least 30 km/s from the stellar rest frame. It is unlikely
that flow velocities in the stellar atmospheres are this fast, so radiative
transfer effects must be responsible for this behavior. Published hydrodynamic
models predict the existence of cool, downflowing material above the shocked
material responsible for the Mg II emission, and we demonstrate that scattering
in this layer can result in Mg II profiles as highly blueshifted as those that
are observed. However, our models also show that scattering within the shock
plays an equally strong role in shaping the Mg II profiles, and our
calculations illustrate the importance of partial redistribution and the
effects of being out of ionization equilibrium.

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The categories of this paper are: alg-geom
9
The categories of this paper are: nlin
12
The categories of this paper are: nucl-th
7
The categories of this paper are: hep-th
33
The categories of this paper are: plasm-ph
35
The categories of this paper are: mtrl-th
21
The categories of this paper are: adap-org
16
The categories of this paper are: stat
18
The categories of this paper are: econ
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The categories of this paper are: dg-ga
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The categories of this paper are: hep-lat
0
The categories of this paper are: hep-ph
13
The categories of this paper are: quant-ph
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The categories of this paper are: cmp-lg
23
The categories of this paper are: solv-int
34
The categories of this paper are: chem-ph