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

Lis, D. C. and Neufeld, D. A. and Phillips, T. G. and Gerin, M. and Neri, R. (2011) Discovery of Water Vapor in the High-redshift Quasar APM 08279+5255 at z = 3.91. Astrophysical Journal Letters, 738 (1). Art. No. L6. ISSN 2041-8205. doi:10.1088/2041-8205/738/1/L6.

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We report a detection of the excited 2_(20)-2_(11) rotational transition of para-H_2O 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 large velocity gradient 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 hydrogen fluoride (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 interstellar medium.

Item Type:Article
Related URLs:
URLURL TypeDescription DOIArticle
Lis, D. C.0000-0002-0500-4700
Neufeld, D. A.0000-0001-8341-1646
Neri, R.0000-0002-7176-4046
Additional Information:© 2011 The American Astronomical Society. Received 2011 June 1; accepted 2011 June 23; published 2011 August 9. This work is based on observations carried out with the IRAM Plateau de Bure interferometer. IRAM is supported by INSU/CNRS (France), MPG (Germany), and IGN (Spain). This research has been supported by NASA through an award issued by JPL/Caltech and by the NSF grant AST-0540882 to the Caltech Submillimeter Observatory. We thank Pierre Cox for allocating Director’s Discretionary Time to allow these observations to be carried out and an anonymous referee for constructive and helpful comments.
Funding AgencyGrant Number
Institut national des sciences de l'Univers (INSU)UNSPECIFIED
Instituto Geográfico Nacional (IGN)UNSPECIFIED
Centre National de la Recherche Scientifique (CNRS)UNSPECIFIED
Subject Keywords:cosmology: observations; galaxies: active; galaxies: high-redshift; galaxies: individual (APM 08279+5255); ISM: molecules
Issue or Number:1
Classification Code:PACS: 98.58.Bz; 98.62.Py; 98.80.Es; 98.54.Aj
Record Number:CaltechAUTHORS:20110922-154954787
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Official Citation:Discovery of Water Vapor in the High-redshift Quasar APM 08279+5255 at z = 3.91 D. C. Lis et al. 2011 ApJ 738 L6
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:25414
Deposited By: Ruth Sustaita
Deposited On:23 Sep 2011 15:21
Last Modified:09 Nov 2021 16:33

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