Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: XMM-Newton observations of the Lockman Hole IV: spectra of the brightest
  AGN   This paper presents the results of a detailed X-ray spectral analysis of a
sample of 123 X-ray sources (46 being type-1 AGN and 28 type-2 AGN) detected
with XMM-Newton in the Lockman Hole field. Using a single power law model our
sources' average spectral slope hardens at faint 0.5-2 keV fluxes but not at
faint 2-10 keV fluxes. We explain the effect in terms of an increase in X-ray
absorption at faint fluxes. The average spectral slope of our sources is ~1.9
with an intrinsic dispersion of ~0.28. We detected X-ray absorption in 37% of
the sources, ~10% in type-1 AGN and ~77% in type-2 AGN. Using X-ray fluxes
corrected for absorption, the fraction of absorbed objects and the absorbing
column density distribution did not vary with X-ray flux. Our type-1 and type-2
AGN do not appear to have different continuum shapes, but the distribution of
intrinsic absorption is different among both classes. A significant fraction of
our type-2 AGN (5 out of 28) were found to display no substantial absorption.
We discuss possible interpretations to this in terms of Compton-thick AGN and
intrinsic Broad Line Region properties. An emission line compatible with Fe
Kalpha was detected in 8 sources with rest frame equivalent widths 120-1000 eV.
The AGN continuum or intrinsic absorption did not depend on X-ray luminosity
and/or redshift. Soft excess emission was detected in 18 objects, but only in 9
could we fit this spectral component with a black body model. The 0.5-2 keV
luminosities of the fitted black body were not significantly different in
type-1 and type-2 AGN, although the temperatures were slightly higher in type-2
AGN than in type-1 AGN. For 9 sources (including 1 type-1 AGN and 3 type-2 AGN)
a scattering model provided a better fit of the soft excess emission.

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The categories of this paper are: cond-mat
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The categories of this paper are: hep-th
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The categories of this paper are: econ
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The categories of this paper are: math
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The categories of this paper are: funct-an
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The categories of this paper are: math-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: quant-ph
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The categories of this paper are: cmp-lg
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The categories of this paper are: mtrl-th
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The categories of this paper are: plasm-ph
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The categories of this paper are: solv-int
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The categories of this paper are: hep-lat
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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: chem-ph