Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: FEDReD II : 3D Extinction Map with 2MASS and Gaia DR2 data   Aims. We aim to map the 3D distribution of the interstellar extinction of the
Milky Way disk up to distances larger than those probed with the Gaia parallax
alone.
  Methods. We apply the FEDReD (Field Extinction-Distance Relation Deconvolver)
algorithm to the 2MASS near-infrared photometry together with the Gaia DR2
astrometry and photometry. This algorithm uses a Bayesian deconvolution
approach, based on an empirical HR-diagram representative of the local thin
disk, in order to map the extinction as a function of distance of various
fields of view.
  Results. We analysed more than 5.6 million stars to obtain an extinction map
of the entire Galactic disk within $|b|<0.24^{\circ}$. This map provides
information up to $5~\mathrm{kpc}$ in the direction of the Galactic centre and
at more than $7~\mathrm{kpc}$ in the direction of the anticentre. This map
reveals the complete shape of structures known locally, such as the Vela
complex or the split of the local arm. Furthermore our extinction map shows
many large "clean bubbles" especially one in the Sagittarius -- Carina complex,
and four others which define a structure that we nickname the butterfly.

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The categories of this paper are: math-ph
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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: q-alg
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The categories of this paper are: stat
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The categories of this paper are: alg-geom
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The categories of this paper are: bayes-an
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The categories of this paper are: adap-org
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The categories of this paper are: hep-th
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The categories of this paper are: quant-ph
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The categories of this paper are: q-fin
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The categories of this paper are: plasm-ph
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The categories of this paper are: cond-mat
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The categories of this paper are: dg-ga
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The categories of this paper are: physics
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The categories of this paper are: q-bio