Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: NGC 4654: gravitational interaction or ram pressure stripping?   The Virgo cluster spiral galaxy NGC 4654 is supposed to be a good candidate
for ongoing ram pressure stripping based on its very asymmetric HI
distribution. However, this galaxy also shows an asymmetric stellar
distribution. Numerical simulations using ram pressure as the only perturbation
can produce a tail structure of the gas content, but cannot account for its
kinematical structure. It is shown that a strong edge-on stripping event can
produce an asymmetric stellar distribution up to 800 Myr after the stripping
event, i.e. the galaxy's closest passage to the cluster center. Simulations
using a gravitational interaction with the companion galaxy NGC 4639 can
account for the asymmetric stellar distribution of NGC 4654, but cannot
reproduce the observed extended gas tail. Only a mixed interaction,
gravitational and ram pressure, can reproduce all observed properties of NGC
4654. It is concluded that NGC 4654 had a tidal interaction ~500 Myr ago and is
continuing to experience ram pressure.

28
The categories of this paper are: alg-geom
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The categories of this paper are: comp-gas
33
The categories of this paper are: plasm-ph
7
The categories of this paper are: hep-th
32
The categories of this paper are: atom-ph
2
The categories of this paper are: math
36
The categories of this paper are: cmp-lg
3
The categories of this paper are: physics
23
The categories of this paper are: solv-int
34
The categories of this paper are: chem-ph
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The categories of this paper are: q-alg
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The categories of this paper are: ao-sci
8
The categories of this paper are: hep-ex
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The categories of this paper are: q-fin
10
The categories of this paper are: q-bio
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The categories of this paper are: patt-sol