Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A Long XMM-Newton Observation of An Extreme Narrow Line Seyfert 1: PG
  1244+026   We explore the origin of the strong soft X-ray excess in Narrow Line Seyfert
1 galaxies using spectral-timing information from a 120ks {\it XMM-Newton}
observation of PG 1244+026. Spectral fitting alone cannot distinguish between a
true additional soft X-ray continuum component and strongly relativistically
smeared reflection, but both models also require a separate soft blackbody
component. This is most likely intrinsic emission from the disc extending into
the lowest energy X-ray bandpass. The {\it RMS} spectra on short timescales
(200-5000s) contain both (non-disk) soft excess and power law emission.
However, the spectrum of the variability on these timescales correlated with
the 4-10 keV lightcurve contains only the power law. Together these show that
there is fast variability of the soft excess which is independent of the 4-10
keV variability. This is inconsistent with a single reflection component making
the soft X-ray excess as this necessarily produces correlated variability in
the 4-10 keV bandpass. Instead, the {\it RMS} and covariance spectra are
consistent with an additional cool Comptonisation component which does not
contribute to the spectrum above 2 keV.

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The categories of this paper are: hep-lat
12
The categories of this paper are: nucl-th
35
The categories of this paper are: mtrl-th
0
The categories of this paper are: hep-ph
16
The categories of this paper are: stat
37
The categories of this paper are: supr-con
13
The categories of this paper are: quant-ph
3
The categories of this paper are: physics
5
The categories of this paper are: gr-qc
9
The categories of this paper are: nlin
30
The categories of this paper are: q-alg
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The categories of this paper are: bayes-an
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The categories of this paper are: nucl-ex
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The categories of this paper are: q-bio
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The categories of this paper are: hep-ex
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The categories of this paper are: chao-dyn