Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Witnessing a merging bullet being stripped in the galaxy cluster,
  RXCJ2359.3-6042   We report the discovery of the merging cluster, RXCJ2359.3-6042, from the
REFLEX II cluster survey and present our results from all three detectors
combined in the imaging and spectral analysis of the XMM-Newton data. Also
known as Abell 4067, this is a unique system, where a compact bullet penetrates
an extended, low density cluster at redshift z=0.099 clearly seen from our
follow-up XMM-Newton observation. The bullet goes right through the central
region of the cluster without being disrupted and we can clearly watch the
process how the bullet component is stripped of its layers outside the core.
There is an indication of a shock heated region in the East of the cluster with
a higher temperature. The bulk temperature of the cluster is about 3.12 keV
implying a lower mass system. Spearheading the bullet is a cool core centred by
a massive early type galaxy. The temperatures and metallicities of a few
regions in the cluster derived from the spectral analysis supports our
conjecture based on the surface brightness image that a much colder compact
component at 1.55 keV with large metallicity (0.75 Zsol) penetrates the main
cluster, where the core of the infalling component survived the merger leaving
stripped gas behind at the centre of the main cluster. We also give an estimate
of the total mass within r500, which is about 2e14Msol from the deprojected
spherical-beta modelling of the cluster in good agreement with other mass
estimates from the M--Tx and M-sigma_v relations.

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The categories of this paper are: cond-mat
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The categories of this paper are: bayes-an
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The categories of this paper are: solv-int
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The categories of this paper are: atom-ph
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The categories of this paper are: q-alg
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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: hep-th
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The categories of this paper are: cmp-lg
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The categories of this paper are: gr-qc
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The categories of this paper are: stat
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The categories of this paper are: patt-sol
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The categories of this paper are: nucl-ex
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The categories of this paper are: hep-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: q-fin