Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Empirical properties of Very Massive Stars   In this contribution we present the properties of the most massive stars
known by the end of 2013. We start with a summary of historical claims for
stars with masses in excess of several hundreds, even thousands of solar
masses. We then describe how we determine masses for single stars. We focus on
the estimates of luminosities and on the related uncertainties. We also
highlight the limitations of evolutionary models used to convert luminosities
into masses. The most luminous single stars in the Galaxy and the Magellanic
Clouds are subsequently presented. The uncertainties on their mass
determinations are described. Finally, we present binary stars. After recalling
some basics of binary analysis, we present the most massive binary systems and
the estimates of their dynamical masses.

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The categories of this paper are: cond-mat
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The categories of this paper are: patt-sol
32
The categories of this paper are: atom-ph
18
The categories of this paper are: econ
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The categories of this paper are: adap-org
36
The categories of this paper are: cmp-lg
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The categories of this paper are: hep-ph
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The categories of this paper are: quant-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: solv-int
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The categories of this paper are: plasm-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: comp-gas
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The categories of this paper are: hep-ex
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The categories of this paper are: alg-geom
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The categories of this paper are: bayes-an