Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Diffuse Light in Hickson Compact Groups: The Dynamically Young System
  HCG 44   Compact groups are associations of a few galaxies in which the environment
plays an important role in galaxy evolution. The low group velocity dispersion
favors tidal interactions and mergers, which may bring stars from galaxies to
the diffuse intragroup light. Numerical simulations of galaxy clusters in
hierarchical cosmologies show that the amount of the diffuse light increases
with the dynamical evolution of the cluster. We search for diffuse light in the
galaxy group HCG 44 in order to determine its luminosity and luminosity
fraction. Combining with literature data, we aim to constrain the dynamical
status of Hickson compact groups. We use Intra Group planetary nebulae (IGPNe)
as tracers of diffuse light. These are detected by the so-called on band-off
band technique. We found 12 emission line objects in HCG 44, none of them
associated with the galaxies of the group. 6/12 emission line objects are
consistent with being IGPNe in HCG 44, but are also consistent with being
Ly$\alpha$ background galaxies. Thus we derive an upper limit to the diffuse
light fraction in HCG 44 of 4.7%. We find a correlation between the fraction of
elliptical galaxies and the amount of diffuse light in Hickson compact groups.
Those with large fraction of diffuse light are those with large fractions in
number and luminosity of E/S0 galaxies. We propose an evolutionary sequence for
Hickson compact groups in which the amount of diffuse light increases with the
dynamical evolution of the group.

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The categories of this paper are: math
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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: eess
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The categories of this paper are: nucl-th
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The categories of this paper are: funct-an
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The categories of this paper are: cs
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The categories of this paper are: stat
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The categories of this paper are: cmp-lg
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The categories of this paper are: hep-ex
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The categories of this paper are: cond-mat
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The categories of this paper are: chao-dyn
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The categories of this paper are: alg-geom
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The categories of this paper are: adap-org
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The categories of this paper are: q-fin
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The categories of this paper are: hep-th