Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Discovery of multiple shells around V838 Monocerotis   We report the discovery of multiple shells around the eruptive variable star
V838 Mon. Two dust shells are seen in IRAS and MSX images, which themselves are
situated in a shell of CO. This securely establishes V838 Mon as an evolved
object. We revisit the light echo, which arises from scattering off the
innermost resolved dust shell, to infer a distance to V838 Mon of >~5.5 kpc.
The dynamical timescales of the ejected shells, location in the Milky Way and
inferred luminosity are consistent with V838 Mon being a low-mass AGB star
experiencing thermal pulses of which the 2002 eruption might have sent the star
into the post-AGB phase. This scenario, however, is inconsistent with the
presence of a (young and massive) B3 V companion.

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The categories of this paper are: mtrl-th
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The categories of this paper are: cs
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The categories of this paper are: eess
2
The categories of this paper are: math
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The categories of this paper are: math-ph
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The categories of this paper are: quant-ph
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The categories of this paper are: atom-ph
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The categories of this paper are: q-alg
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The categories of this paper are: ao-sci
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The categories of this paper are: hep-lat
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The categories of this paper are: plasm-ph
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The categories of this paper are: supr-con
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The categories of this paper are: cmp-lg
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The categories of this paper are: cond-mat
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The categories of this paper are: funct-an
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The categories of this paper are: bayes-an