Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Initial Results from The Spitzer Young Stellar Cluster Survey   We report initial results from IRAC observations of four young stellar
clusters. These regions are part of a larger Spitzer survey of 31 young stellar
groups and clusters within 1 kpc of the Sun. In each of the four clusters,
there are between 39 and 85 objects with colors inconsistent with reddened
stellar photospheres. We identify these objects as young stars with significant
emission from circumstellar dust. Applying an analysis developed in a companion
paper (Allen et al. 2004), we classify these objects as either pre-main
sequence stars with disks (class II) or protostellar objects (class I). These
show that the sites of recent star formation are distributed over multi-parsec
size scales. In two clusters, Cepheus C and S140, we find protostars embedded
in filamentary dark clouds seen against diffuse emission in the IRAC bands.

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The categories of this paper are: math
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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: gr-qc
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The categories of this paper are: q-alg
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The categories of this paper are: patt-sol
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The categories of this paper are: cs
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The categories of this paper are: cmp-lg
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The categories of this paper are: chao-dyn
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The categories of this paper are: hep-ph
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The categories of this paper are: math-ph
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The categories of this paper are: physics
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The categories of this paper are: dg-ga
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The categories of this paper are: eess
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The categories of this paper are: adap-org