Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: First Constraints on Iron Abundance versus Reflection Fraction from the
  Seyfert~1 Galaxy MCG--6-30-15   We report on a joint ASCA and RXTE observation spanning an $\sim$ 400~ks time
interval of the bright Seyfert~1 galaxy MCG--6-30-15. The data clearly confirm
the presence of a broad skewed iron line ($W_{K\alpha} \sim$ 266 eV) and
Compton reflection continuum at higher energies reported in our previous paper.
We also investigate whether the gravitational and Doppler effects that affect
the iron line may also be manifest in the reflected continuum. The uniqueness
of this data set is underlined by the extremely good statistics that we obtain
from the approximately four million photons that make up the 2-20 keV RXTE PCA
spectrum alone. This, coupled with the high energy coverage of HEXTE and the
spectral resolution of ASCA in the iron line regime has allowed us to constrain
the relationship between abundance and reflection fraction for the first time
at the 99 per cent confidence level. The reflection fraction is entirely
consistent with a flat disk, i.e. the cold material subtends $\rm 2 \pi$ sr at
the source, to an accuracy of 20 per cent. Monte Carlo simulations show that
the observed strong iron line intensity is explained by an overabundance of
iron by a factor of $\sim$ 2 and an underabundance of the lower-Z elements by a
similar factor. By considering non-standard abundances, a clear and consistent
picture can be made in which both the iron line and reflection continuum come
from the same material such as e.g. an accretion disk.

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The categories of this paper are: atom-ph
11
The categories of this paper are: hep-lat
8
The categories of this paper are: hep-ex
20
The categories of this paper are: acc-phys
31
The categories of this paper are: ao-sci
14
The categories of this paper are: math-ph
28
The categories of this paper are: alg-geom
10
The categories of this paper are: q-bio
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The categories of this paper are: chao-dyn
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The categories of this paper are: eess
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The categories of this paper are: plasm-ph
30
The categories of this paper are: q-alg
29
The categories of this paper are: funct-an
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The categories of this paper are: supr-con
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The categories of this paper are: comp-gas
9
The categories of this paper are: nlin