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arXiv · 1308.2963

Water Absorption from Gas Very Near the Massive Protostar AFGL 2136 IRS 1

Nick Indriolo·D. A. Neufeld·A. Seifahrt·M. J. Richter
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Abstract

We present ground-based observations of the nu_1 and nu_3 fundamental bands of H2O toward the massive protostar AFGL 2136 IRS 1, identifying absorption features due to 47 different ro-vibrational transitions between 2.468 micron and 2.561 micron. Analysis of these features indicates the absorption arises in warm (T=506+-25 K), very dense (n(H2)>5*10^9 cm^-3) gas, suggesting an origin close to the central protostar. The total column density of warm water is estimated to be N(H2O)=(1.02+-0.02)*10^19 cm^-2, giving a relative abundance of N(H2O)/N(H2)~10^-4. Our study represents the first extensive use of water vapor absorption lines in the near infrared, and demonstrates the utility of such observations in deriving physical parameters.

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Nick Indriolo, D. A. Neufeld, A. Seifahrt, M. J. Richter. 2013-08-13. Water Absorption from Gas Very Near the Massive Protostar AFGL 2136 IRS 1. https://doi.org/10.1088/0004-637x%2F776%2F1%2F8

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