Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: AGN feedback and gas mixing in the core of NGC 4636   Chandra observations of NGC 4636 show disturbances in the galaxy X-ray halo,
including arm-like high surface brightness features (tentatively identified as
AGN driven shocks) and a possible cavity on the west side of the galaxy core.
We present Chandra and XMM spectral maps of NGC 4636 which confirm the presence
of the cavity and show it to be bounded by the arm features. The maps also
reveal a ~15 kpc wide plume of low temperature, high abundance gas extending
25-30 kpc to the southwest of the galaxy. The cavity appears to be embedded in
this plume, and we interpret the structure as being entrained gas drawn out of
the galaxy core during previous episodes of AGN activity. The end of the plume
is marked by a well defined edge, with significant falls in surface brightness,
temperature and abundance, indicating a boundary between galaxy and
group/cluster gas. This may be evidence that as well as preventing gas cooling
through direct heating, AGN outbursts can produce significant gas mixing,
disturbing the temperature structure of the halo and transporting metals out
from the galaxy into the surrounding intra-group medium.

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The categories of this paper are: math
13
The categories of this paper are: quant-ph
34
The categories of this paper are: chem-ph
32
The categories of this paper are: atom-ph
16
The categories of this paper are: stat
21
The categories of this paper are: adap-org
27
The categories of this paper are: comp-gas
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The categories of this paper are: cond-mat
0
The categories of this paper are: hep-ph
9
The categories of this paper are: nlin
17
The categories of this paper are: q-fin
8
The categories of this paper are: hep-ex
30
The categories of this paper are: q-alg
36
The categories of this paper are: cmp-lg
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The categories of this paper are: alg-geom
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The categories of this paper are: nucl-th