Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The NGC 4013 tale: a pseudo-bulged, late-type spiral shaped by a major
  merger   Many spiral galaxy haloes show stellar streams with various morphologies when
observed with deep images. The origin of these tidal features is discussed,
either coming from a satellite infall or caused by residuals of an ancient,
gas-rich major merger. By modelling the formation of the peculiar features
observed in the NGC 4013 halo, we investigate their origin. By using GADGET -2
with implemented gas cooling, star formation, and feedback, we have modelled
the overall NGC 4013 galaxy and its associated halo features. A gas-rich major
merger occurring 2.7-4.6 Gyr ago succeeds in reproducing the NGC 4013 galaxy
properties, including all the faint stellar features, strong gas warp,
boxy-shaped halo and vertical 3.6 mum luminosity distribution. High gas
fractions in the progenitors are sufficient to reproduce the observed thin and
thick discs, with a small bulge fraction, as observed. A major merger is able
to reproduce the overall NGC 4013 system, including the warp strength, the red
colour and the high stellar mass density of the loop, while a minor merger
model cannot. Because the gas-rich model suffices to create a pseudo-bulge with
a small fraction of the light, NGC 4013 is perhaps the archetype of a late-type
galaxy formed by a relatively recent merger. Then late type, pseudo-bulge
spirals are not mandatorily made through secular evolution, and the NGC 4013
properties also illustrate that strong warps in isolated galaxies may well
occur at a late phase of a gas-rich major merger.

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The categories of this paper are: stat
27
The categories of this paper are: comp-gas
20
The categories of this paper are: acc-phys
9
The categories of this paper are: nlin
33
The categories of this paper are: plasm-ph
23
The categories of this paper are: solv-int
22
The categories of this paper are: chao-dyn
28
The categories of this paper are: alg-geom
4
The categories of this paper are: cond-mat
32
The categories of this paper are: atom-ph
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The categories of this paper are: eess
18
The categories of this paper are: econ
31
The categories of this paper are: ao-sci
3
The categories of this paper are: physics
10
The categories of this paper are: q-bio
7
The categories of this paper are: hep-th