Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Chandra X-Ray Observatory: Progress Report and Highlights   Over the past 13 years, the Chandra X-ray Observatory's ability to provide
high resolution X-ray images and spectra have established it as one of the most
versatile and powerful tools for astrophysical research in the 21st century.
Chandra explores the hot, x-ray-emitting regions of the universe, observing
sources with fluxes spanning more than 10 orders of magnitude, from the X-ray
brightest, Sco X-1, to the faintest sources in the Chandra Deep Field South
survey. Thanks to its continuing operational life, the Chandra mission now also
provides a long observing baseline which, in and of itself, is opening new
research opportunities. In addition, observations in the past few years have
deepened our understanding of the co-evolution of supermassive black holes and
galaxies, the details of black hole accretion, the nature of dark energy and
dark matter, the details of supernovae and their progenitors, the interiors of
neutron stars, the evolution of massive stars, and the high-energy environment
of protoplanetary nebulae and even the interaction of an exo-planet with its
star. Here we update the technical status, highlight some of the scientific
results, and very briefly discuss future prospects. We fully expect that the
Observatory will continue to provide outstanding scientific results for many
years to come.

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The categories of this paper are: q-fin
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The categories of this paper are: quant-ph
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The categories of this paper are: nucl-ex
31
The categories of this paper are: ao-sci
2
The categories of this paper are: math
4
The categories of this paper are: cond-mat
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The categories of this paper are: eess
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The categories of this paper are: solv-int
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The categories of this paper are: comp-gas
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The categories of this paper are: hep-lat
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The categories of this paper are: nucl-th
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The categories of this paper are: hep-ex
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The categories of this paper are: acc-phys
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The categories of this paper are: q-alg
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The categories of this paper are: gr-qc
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The categories of this paper are: bayes-an