Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A High Resolution Study of the Hydra A Cluster with Chandra: Comparison
  of the Core Mass Distribution with Theoretical Predictions and Evidence for
  Feedback in the Cooling Flow   The cooling flow cluster Hydra A was observed during the orbital activation
and calibration phase of the Chandra Observatory. While the X-ray image of the
cluster exhibits complex structure in the central region as reported in
McNamara $etal$, the large scale X-ray morphology of the cluster is fairly
smooth. A spectroscopic analysis of the ACIS data shows that the gas
temperature in Hydra A increases outward, reaches a maximum temperature of 4
keV at 200 kpc, and then decreases slightly at larger radii. The distribution
of heavy elements is nonuniform, with a factor of two increase in the Fe and Si
abundances within the central 100 kpc. Beyond the central 100 kpc the Si-to-Fe
abundance ratio is twice solar, while the Si-to-Fe ratio of the central excess
is consistent with the solar value. One of the more surprising results is the
lack of spectroscopic evidence for multiphase gas within the bulk of the
cooling flow. Beyond the central 30 kpc, the ACIS spectra are adequately fit
with a single temperature model. The addition of a cooling flow component does
not significantly improve the fit. Only within the central 30 kpc (where the
cooling time is less than 1~Gyr), is there spectroscopic evidence for
multiphase gas. However, the spectroscopic mass deposition rate is more than a
factor of 10 less than the morphologically derived mass accretion rate at 30
kpc. We propose that the cooling flow region is convectively unstable due to
heating by the central radio source which significantly reduces the net
accretion rate.

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The categories of this paper are: bayes-an
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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: supr-con
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The categories of this paper are: q-bio
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The categories of this paper are: hep-th
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The categories of this paper are: patt-sol
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The categories of this paper are: atom-ph
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The categories of this paper are: hep-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: dg-ga
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The categories of this paper are: cond-mat
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The categories of this paper are: cs
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The categories of this paper are: chao-dyn
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The categories of this paper are: math-ph
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The categories of this paper are: quant-ph