Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spectral energy distributions and age estimates of 104 M31 globular
  clusters   We present photometry of 104 M31 globular clusters (GCs) and GC candidates in
15 intermediate-band filters of the Beijing-Arizona-Taiwan-Connecticut (BATC)
photometric system. The GCs and GC candidates were selected from the Revised
Bologna Catalog (v.3.5). We obtain the cluster ages by comparing the
photometric data with up-to-date theoretical synthesis models. The photometric
data used are {\sl GALEX} far- and near-ultraviolet and 2MASS near-infrared
$JHK_{\rm s}$ magnitudes, combined with optical photometry. The ages of our
sample clusters cover a large range, although most clusters are younger than 10
Gyr. Combined with the ages obtained in our series of previous papers focusing
on the M31 GC system, we present the full M31 GC age distribution. The M31 GC
system contains populations of young and intermediate-age GCs, as well as the
`usual' complement of well-known old GCs, i.e., GCs of similar age as the
majority of the Galactic GCs. In addition, young GCs (and GC candidates) are
distributed nearly uniformly in radial distance from the center of M31, while
most old GCs (and GC candidates) are more strongly concentrated.

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The categories of this paper are: nlin
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The categories of this paper are: hep-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: plasm-ph
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The categories of this paper are: chem-ph
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The categories of this paper are: cs
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The categories of this paper are: comp-gas
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The categories of this paper are: bayes-an
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The categories of this paper are: eess
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The categories of this paper are: dg-ga
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The categories of this paper are: quant-ph
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The categories of this paper are: stat
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The categories of this paper are: ao-sci
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The categories of this paper are: hep-ex
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The categories of this paper are: alg-geom
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The categories of this paper are: physics