Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Analysis of the Herschel/HEXOS Spectral Survey Towards Orion South: A
  massive protostellar envelope with strong external irradiation   We present results from a comprehensive submillimeter spectral survey toward
the source Orion South, based on data obtained with the HIFI instrument aboard
the \textit{Herschel Space Observatory}, covering the frequency range 480 to
1900 GHz. We detect 685 spectral lines with S/N $>$ 3$\sigma$, originating from
52 different molecular and atomic species. We model each of the detected
species assuming conditions of Local Thermodynamic Equilibrium. This analysis
provides an estimate of the physical conditions of Orion South (column density,
temperature, source size, \& V$_{LSR}$). We find evidence for three different
cloud components: a cool (T$_{ex} \sim 20-40$ K), spatially extended ($> 60"$),
and quiescent ($\Delta V_{FWHM} \sim 4$ km s $^{-1}$) component; a warmer
(T$_{ex} \sim 80-100$ K), less spatially extended ($\sim 30"$), and dynamic
($\Delta V_{FWHM} \sim 8$ km s $^{-1}$) component, which is likely affected by
embedded outflows; and a kinematically distinct region (T$_{ex}$ $>$ 100 K;
V$_{LSR}$ $\sim$ 8 km s $^{-1}$), dominated by emission from species which
trace ultraviolet irradiation, likely at the surface of the cloud. We find
little evidence for the existence of a chemically distinct "hot core"
component, likely due to the small filling factor of the hot core or hot cores
within the \textit{Herschel} beam. We find that the chemical composition of the
gas in the cooler, quiescent component of Orion South more closely resembles
that of the quiescent ridge in Orion-KL. The gas in the warmer, dynamic
component, however, more closely resembles that of the Compact Ridge and
Plateau regions of Orion-KL, suggesting that higher temperatures and shocks
also have an influence on the overall chemistry of Orion South.

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The categories of this paper are: bayes-an
36
The categories of this paper are: cmp-lg
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The categories of this paper are: plasm-ph
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The categories of this paper are: adap-org
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The categories of this paper are: math
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The categories of this paper are: econ
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The categories of this paper are: funct-an
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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: supr-con
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The categories of this paper are: comp-gas
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The categories of this paper are: nlin
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The categories of this paper are: physics
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The categories of this paper are: stat
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The categories of this paper are: q-alg
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The categories of this paper are: q-bio