%0 Journal Article
%T Water Absorption from Gas Very Near the Massive Protostar AFGL 2136 IRS 1
%A Nick Indriolo
%A D. A. Neufeld
%A A. Seifahrt
%A M. J. Richter
%J Physics
%D 2013
%I arXiv
%R 10.1088/0004-637X/776/1/8
%X 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.
%U http://arxiv.org/abs/1308.2963v1