Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Resonant Absorption in the AGN spectra emerging from photoionized gas:
  differences between steep and flat ionizing continua   We present photoionization models accounting for both photoelectric and
resonant absorption. Resonance absorption lines from C, O, Ne, Mg, Si S and Fe
between 0.1 and 10 keV are treated. In particular we consider the complex of
almost 60 strong Fe L absorption lines around 1 keV. We calculate profiles,
intensities and equivalent widths of each line, considering both Doppler and
natural broadening mechanisms. Doppler broadening includes a term accounting
for turbulence of the gas along the line of sight. We computed spectra
transmitted by gas illuminated by drastically different ionizing continua and
compared them to spectra observed in flat X-ray spectrum, broad optical
emission line type 1 AGN, and steep X-ray spectrum, narrow optical emission
line type 1 AGN. We show that the $\sim 1$ keV absorption feature observed in
moderate resolution X-ray spectra of several Narrow Line Seyfert 1 galaxies can
be explained by photoionization models, taking into account for resonance
absorption, without requiring relativistic outflowing velocities of the gas, if
the physical properties of these absorbers are close to those found in flat
X-ray spectrum Seyfert 1 galaxies.

18
The categories of this paper are: econ
11
The categories of this paper are: hep-lat
4
The categories of this paper are: cond-mat
12
The categories of this paper are: nucl-th
21
The categories of this paper are: adap-org
9
The categories of this paper are: nlin
3
The categories of this paper are: physics
37
The categories of this paper are: supr-con
29
The categories of this paper are: funct-an
28
The categories of this paper are: alg-geom
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The categories of this paper are: eess
20
The categories of this paper are: acc-phys
32
The categories of this paper are: atom-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: nucl-ex
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The categories of this paper are: bayes-an