Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A Gravitational Lens Solution for IRAS F10214+4724   We show that the high redshift IRAS source F10214 is highly magnified by the
gravitational field of an intervening elliptical galaxy, accounting for its
many anomalous properties. Detailed radio and near-IR images identify the IRAS
source with a symmetric arc, centered on a red object, or lensing galaxy. To
explain the observed structures, the center of the source must much more highly
magnified than its outer regions. Lensing predicts a small counterimage to the
arc, which we find adjacent to the lensing galaxy. A red component in the
observed spectrum suggests a lens redshift of unity, and the lens model yields
a mass estimate of $M(r<3kpc)\approx10^{11}{M_solar}$, consistent with an
ordinary elliptical galaxy. We present new high-resolution optical images which
show a thin arc of emission, implying an intrinsically small source ($<0.5kpc$)
which is highly magnified ($\sim20\times$). Since the optical is strongly
polarized with a Seyfert~II spectrum, we propose that the optical arc is
magnified image of the inner region of an obscured AGN. The obscuring ``torus''
will be similarly magnified, naturally accounting for the large IR flux. We
show that finding objects like F10214+4724 in redshift surveys is probable,
given the level of magnification bias expected for compact luminous IRAS
sources. Such cases represent the obscured AGN counterparts to the lensed QSO
population and, because of their extended sizes, are useful in determining the
mass distribution in the lensing galaxies.

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The categories of this paper are: chem-ph
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The categories of this paper are: supr-con
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The categories of this paper are: nucl-ex
9
The categories of this paper are: nlin
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The categories of this paper are: physics
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The categories of this paper are: plasm-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: quant-ph
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The categories of this paper are: cond-mat
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The categories of this paper are: math
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The categories of this paper are: dg-ga
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The categories of this paper are: funct-an
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The categories of this paper are: hep-th
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The categories of this paper are: gr-qc
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The categories of this paper are: econ
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The categories of this paper are: hep-ex