Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: First results of X-shooter observations of IGR sources   X-shooter is a second generation ESO-VLT instrument that had its first light
in October 2009. It is a single object medium-resolution spectrograph whose
main feature is the capability of covering simultaneously in a single
observation the range from 3000 to 24000 Angstrom. This unique capability is
very well suited to investigate the complex spectra of the optical counterparts
of X/gamma ray sources which usually display signatures of different components
in emission and absorption. In July 2012 we observed with X-shooter a small
sample of counterparts of bright IGR sources in order to better determine their
physical properties. We present the first results of these observations.

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The categories of this paper are: supr-con
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The categories of this paper are: cond-mat
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The categories of this paper are: quant-ph
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The categories of this paper are: hep-lat
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The categories of this paper are: bayes-an
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The categories of this paper are: nucl-th
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The categories of this paper are: cmp-lg
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The categories of this paper are: q-bio
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The categories of this paper are: math-ph
2
The categories of this paper are: math
1
The categories of this paper are: cs
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The categories of this paper are: hep-ex
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The categories of this paper are: mtrl-th
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The categories of this paper are: chem-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: acc-phys