Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Pristine survey -- VII. A cleaner view of the Galactic outer halo
  using blue horizontal branch stars   We use the Pristine survey CaHK narrow-band photometry, combined with the
SDSS ugr photometry, to provide a cleaner sample of blue horizontal branch
stars in the Galactic halo out to large distances. We demonstrate a
completeness of 91% and a purity of 93% with respect to available spectroscopic
classifications. We subsequently use our new clean sample of these standard
candles to investigate the substructure in the Galactic halo over the Pristine
footprint. Among other features, this allows for a careful tracing of multiple
parts of the Sagittarius stream, providing a measurement independent from other
tracers used and reaching larger distances. Moreover, we demonstrate with this
clean and complete sample that the halo follows a density profile with a
negative power-law slope of 3.5 - 4.0. As the relatively shallow SDSS u-band is
the limiting factor in this technique, we foresee large potential for combining
Pristine survey photometry with the much deeper u-band photometry from the
Canada-France-Imaging Survey.

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The categories of this paper are: math-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: stat
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The categories of this paper are: chao-dyn
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The categories of this paper are: hep-ex
33
The categories of this paper are: plasm-ph
3
The categories of this paper are: physics
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The categories of this paper are: funct-an
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The categories of this paper are: nucl-ex
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The categories of this paper are: nlin
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The categories of this paper are: atom-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: econ
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The categories of this paper are: comp-gas
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The categories of this paper are: q-bio
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The categories of this paper are: nucl-th