Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A population of hot, dusty ultra-luminous galaxies at z~2   We report spectroscopic redshifts for 18 microJy-radio galaxies at mean
redshift of z=2.2 that are faint at both submmillimeter (submm) and optical
wavelengths. While the radio fluxes of these galaxies could indicate
far-infrared (far-IR) luminosities comparable to high-redshift
submillimeter-selected galaxies (>10^12 Lsun), none are detected in the submm.
We propose that this new population of galaxies represents an extension of the
high-redshift submm galaxy population, but with hotter characteristic dust
temperatures that shift the peak of their far-IR emission to shorter
wavelengths, reducing the submm flux below the sensitivity of current
instruments. Therefore, surveys in the submm waveband may miss up to half of
the most luminous, dusty galaxies at z~2. Mid-infrared observations with
Spitzer will be a powerful tool to test this hypothesis.

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The categories of this paper are: plasm-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: gr-qc
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The categories of this paper are: quant-ph
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The categories of this paper are: cmp-lg
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The categories of this paper are: econ
0
The categories of this paper are: hep-ph
14
The categories of this paper are: math-ph
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The categories of this paper are: atom-ph
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The categories of this paper are: dg-ga
2
The categories of this paper are: math
9
The categories of this paper are: nlin
1
The categories of this paper are: cs
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The categories of this paper are: q-fin
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The categories of this paper are: hep-lat
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The categories of this paper are: nucl-ex