Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Correlation Between H\alpha\ Emission and Visual Magnitude During
  Long-Term Variations in Classical Be Stars   H\alpha\ equivalent widths and UBV magnitudes are calculated for Be star disk
models that grow in size and/or density with time. We show that these simple
models are consistent with the known Be star classes of positive and inverse
correlations between long-term variations in H\alpha\ and V magnitude as
identified by Harmanec. We support the conclusion of Harmanec that the
distinction is controlled by the inclination of the disk to the line of sight.
We demonstrate that the strength of these correlations, particularly those of
an inverse correlation where the system becomes fainter as the H\alpha\
emission strength grows, is strongly influenced by the scale height of the
inner Be star disk and the extent of the gravitational darkening of the central
B star due to rapid rotation. This dependence may allow coordinated
spectroscopic and photometric observations to better constrain these poorly
known Be star parameters.

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The categories of this paper are: hep-lat
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The categories of this paper are: hep-ph
27
The categories of this paper are: comp-gas
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The categories of this paper are: gr-qc
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The categories of this paper are: acc-phys
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The categories of this paper are: quant-ph
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The categories of this paper are: supr-con
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The categories of this paper are: bayes-an
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The categories of this paper are: atom-ph
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The categories of this paper are: eess
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The categories of this paper are: alg-geom
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The categories of this paper are: q-bio
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The categories of this paper are: ao-sci
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The categories of this paper are: plasm-ph
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The categories of this paper are: q-fin
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The categories of this paper are: solv-int