Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A Merger Origin for X-Structures in S0 Galaxies   Using numerical simulation, we study the response of a disk galaxy to a
merger involving a low-mass satellite companion. During a prograde satellite
accretion, the disk galaxy forms a strong bar in response to the perturbation
of the companion. After the accretion event is over, the bar buckles vertically
due to a bending instability, sending disk material well out of the disk plane.
The material forms into an X-shaped feature when seen edge-on, morphologically
similar to X-structures observed in several S0/Sa galaxies. The mechanism
described here unites previously suggested accretion and bar instability
hypotheses for forming X-structures into a self-consistent scenario for
merger-induced formation and evolution of S0 galaxies. To complement these
models, we also present observations of the peculiar S0 galaxy Hickson 87a. The
thick disk, isophotal warping, and strong X-structure described in the merger
model are all evident in Hickson 87a, suggesting this galaxy may be an
excellent example of such merger-induced galaxy evolution.

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The categories of this paper are: chem-ph
27
The categories of this paper are: comp-gas
13
The categories of this paper are: quant-ph
15
The categories of this paper are: nucl-ex
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The categories of this paper are: atom-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: adap-org
3
The categories of this paper are: physics
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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: bayes-an
5
The categories of this paper are: gr-qc
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The categories of this paper are: econ
2
The categories of this paper are: math
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The categories of this paper are: mtrl-th
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The categories of this paper are: cmp-lg