Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Observations of multiple populations in star clusters   An increasing number of photometric observations of multiple stellar
populations in Galactic globular clusters is seriously challenging the paradigm
of GCs hosting single, simple stellar populations. These multiple populations
manifest themselves in a split of different evolutionary sequences as observed
in the cluster color-magnitude diagrams. Multiple stellar populations have been
identified in Galactic and Magellanic Cloud clusters. In this paper we will
summarize the observational scenario.

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The categories of this paper are: plasm-ph
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The categories of this paper are: mtrl-th
18
The categories of this paper are: econ
10
The categories of this paper are: q-bio
12
The categories of this paper are: nucl-th
26
The categories of this paper are: bayes-an
7
The categories of this paper are: hep-th
24
The categories of this paper are: dg-ga
9
The categories of this paper are: nlin
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The categories of this paper are: solv-int
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The categories of this paper are: quant-ph
14
The categories of this paper are: math-ph
28
The categories of this paper are: alg-geom
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The categories of this paper are: chem-ph
11
The categories of this paper are: hep-lat
3
The categories of this paper are: physics