Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Milky Way-Like Gas Excitation in an Ultrabright Submillimeter Galaxy at
  $z=1.6$   Based on observations with the IRAM 30-m and Yebes 40-m telescopes, we report
evidence of the detection of Milky Way-like, low-excitation molecular gas, up
to the transition CO($J=5-4$), in a distant, dusty star-forming galaxy at
$z_{CO}=1.60454$. WISE J122651.0+214958.8 (alias SDSSJ1226, the Cosmic
Seahorse), is strongly lensed by a foreground galaxy cluster at $z=0.44$ with a
source magnification of $\mu=9.5\pm0.7$. This galaxy was selected by
cross-correlating near-to-mid infrared colours within the full-sky AllWISE
survey, originally aiming to discover rare analogs of the archetypical strongly
lensed submillimeter galaxy SMM J2135-0102, the Cosmic Eyelash. We derive an
apparent (i.e. not corrected for lensing magnification) rest-frame 8-1000
$\mu$m infrared luminosity of $\mu L_\mathrm{IR}=1.66^{+0.04}_{-0.04}\times
10^{13}$ L$_\odot$ and apparent star-formation rate
$\mu\mathrm{SFR}_\mathrm{IR}=2960\pm70$ M$_\odot$ yr$^{-1}$. SDSSJ1226 is
ultra-bright at $S_{350\mu m}\simeq170$ mJy and shows similarly bright low-$J$
CO line intensities as SMM J2135-0102, however, with exceptionally small
CO($J=5-4$) intensity. We consider different scenarios to reconcile our
observations with typical findings of high-$z$ starbursts, and speculate about
the presence of a previously unseen star-formation mechanism in cosmic noon
submillimeter galaxies. In conclusion, the remarkable low line luminosity ratio
$r_{5,2}=0.11\pm0.02$ is best explained by an extended, main-sequence
star-formation mode -- representing a missing link between starbursts to
low-luminosity systems during the epoch of peak star-formation history.

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The categories of this paper are: bayes-an
8
The categories of this paper are: hep-ex
24
The categories of this paper are: dg-ga
12
The categories of this paper are: nucl-th
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The categories of this paper are: alg-geom
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The categories of this paper are: funct-an
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The categories of this paper are: q-alg
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The categories of this paper are: nlin
7
The categories of this paper are: hep-th
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The categories of this paper are: plasm-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: chem-ph
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The categories of this paper are: math-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: econ
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The categories of this paper are: nucl-ex