Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: X-ray and soft gamma-ray spectra of Broad-Line Radio Galaxies   We study X-ray and soft gamma-ray spectral properties of BLRGs using data
from Ginga, ASCA, OSSE and EXOSAT. The X-ray spectra are well fitted by an
intrinsic power-law continuum with an energy index of alpha ~ 0.7, moderately
absorbed by a cold medium. In addition, the Ginga spectra show Fe K-alpha lines
with an average equivalent width of ~ 100 eV, and, in some cases, Compton
reflection humps. However, the latter components are significantly weaker than
both those seen in radio-quiet Seyferts and those expected if the Fe K-alpha
lines were due to reflection. Some ASCA and EXOSAT spectra show soft X-ray
excesses below ~ 3 keV. When that component is taken into account, the Fe
K-alpha lines in the ASCA data become unresolved with equivalent widths < 200
eV. Multiple observations of 3C 390.3 and 3C 382 show the Fe K-alpha line
approximately constant in flux but accompanied by strong continuum variations.
This indicates the bulk of the line is formed by matter at a distance much
larger than an accretion-disk scale, consistent with the ASCA line width
measurements. The column density of the matter required to account for the
observed line fluxes is N_H > 10^23 cm^-2. Such a medium is in the
line-of-sight in 3C 445 but it has to be out of it in other objects, in which
the observed N_H are substantially lower. Thus, a cold medium with that N_H and
covering a large solid angle is out of the line-of-sight in most objects. The
spectra of BLRGs break and become softer above ~ 100 keV, as shown by a
simultaneous ASCA/OSSE observation of 3C 120 and by the OSSE spectra being on
average much softer than the X-ray spectra. Finally, we find the X-ray and
gamma-ray spectral properties of Cen A intrinsically very similar to BLRGs
studied here.

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The categories of this paper are: cs
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The categories of this paper are: q-alg
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The categories of this paper are: adap-org
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The categories of this paper are: q-fin
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The categories of this paper are: comp-gas
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The categories of this paper are: plasm-ph
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The categories of this paper are: ao-sci
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The categories of this paper are: hep-ex
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The categories of this paper are: q-bio
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The categories of this paper are: math-ph
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The categories of this paper are: physics
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The categories of this paper are: nucl-ex
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The categories of this paper are: stat
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The categories of this paper are: acc-phys
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The categories of this paper are: gr-qc
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The categories of this paper are: funct-an