Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spatially-Resolved Study of Recombining Plasma in W49B Using XMM-Newton   W49B is the youngest SNR to date that exhibits recombining plasma. The two
prevailing theories of this overionization are rapid cooling via adiabatic
expansion or through thermal conduction with an adjacent cooler medium. To
constrain the origin of the recombining plasma in W49B, we perform a
spatially-resolved spectroscopic study of deep XMM-Newton data across 46
regions. We adopt a 3-component model (with one ISM and two ejecta components),
and we find that recombining plasma is present throughout the entire SNR, with
increasing overionization from east to west. The latter result is consistent
with previous studies, and we attribute the overionization in the west to
adiabatic expansion. However, our findings contrast these prior works as we
find evidence of overionization in the east as well. As the SNR is interacting
with molecular material there, we investigate the plausibility of thermal
conduction as the origin of the rapid cooling. We show that based on the
estimated timescales, it is possible that small-scale thermal conduction
through evaporation of clumpy, dense clouds with a scale of 0.1-1.0 pc can
explain the observed overionization in the east.

5
The categories of this paper are: gr-qc
2
The categories of this paper are: math
25
The categories of this paper are: patt-sol
0
The categories of this paper are: hep-ph
22
The categories of this paper are: chao-dyn
19
The categories of this paper are: eess
31
The categories of this paper are: ao-sci
16
The categories of this paper are: stat
37
The categories of this paper are: supr-con
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The categories of this paper are: cond-mat
28
The categories of this paper are: alg-geom
3
The categories of this paper are: physics
26
The categories of this paper are: bayes-an
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The categories of this paper are: mtrl-th
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The categories of this paper are: cs
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The categories of this paper are: q-bio