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arXiv · 1106.4784

Discovery of Water Vapor in the High-Redshift Quasar APM 08279+5255 at Z=3.91

D. C. Lis·D. A. Neufeld·T. G. Phillips·M. Gerin·R. Neri
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Abstract

We report a detection of the excited 220-211 rotational transition of para-H2O in APM 08279+5255 using the IRAM Plateau de Bure interferometer. At z = 3.91, this is the highest-redshift detection of interstellar water to date. From LVG modeling, we conclude that this transition is predominantly radiatively pumped and on its own does not provide a good estimate of the water abundance. However, additional water transitions are predicted to be detectable in this source, which would lead to an improved excitation model. We also present a sensitive upper limit for the HF J = 1 - 0 absorption toward APM 08279+5255. While the face-on geometry of this source is not favorable for absorption studies, the lack of HF absorption is still puzzling and may be indicative of a lower fluorine abundance at z = 3.91 compared with the Galactic ISM.

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D. C. Lis, D. A. Neufeld, T. G. Phillips, M. Gerin, R. Neri. 2011-06-23. Discovery of Water Vapor in the High-Redshift Quasar APM 08279+5255 at Z=3.91. https://doi.org/10.1088/2041-8205%2F738%2F1%2Fl6

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