Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: X-raying Chemical Evolution and Galaxy Formation in The Antennae   We present the integrated 411 ks {\it Chandra} ACIS-S exposure of the
Antennae galaxies (NGC 4038/39). Besides a rich population of point-like
sources, this spectacular image reveals a spatially and spectrally complex hot
diffuse gaseous component. For the first time we detect intense line emission
from Fe, Ne, Mg and Si in The Antennae, and obtain a detailed picture of
spatially varied metal abundances in the hot interstellar medium (ISM) of a
galaxy. In certain regions, the abundances of $\alpha$-elements may be many
times solar, while the Fe abundance is sub-solar or near-solar. The differences
in the local metal enrichment of the hot ISM may be related to the local star
formation rates and to the degree of confinement of the enriched hot ISM. We
also report large-scale gaseous features, including two gigantic,
$\sim$10-kpc-scale `loops' extending to the South of the merging disks, and a
low-surface-brightness hot halo, extending out to $\sim$18 kpc. These features
may be related to superwinds from the starburst in The Antennae or result from
the merger hydrodynamics. Their long cooling times suggest that they may
persist to form the hot X-ray halo of the emerging elliptical galaxy.

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The categories of this paper are: acc-phys
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The categories of this paper are: hep-ex
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The categories of this paper are: cond-mat
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The categories of this paper are: alg-geom
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The categories of this paper are: funct-an
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The categories of this paper are: nucl-th
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The categories of this paper are: ao-sci
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The categories of this paper are: math-ph
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The categories of this paper are: cs
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The categories of this paper are: chem-ph
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The categories of this paper are: physics
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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: hep-th
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The categories of this paper are: econ
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The categories of this paper are: q-bio