EDP Sciences
Free Access
Volume 402, Number 2, May I 2003
Page(s) 635 - 645
Section Formation, structure and evolution of stars
DOI https://doi.org/10.1051/0004-6361:20030293
Published online 14 April 2003

A&A 402, 635-645 (2003)
DOI: 10.1051/0004-6361:20030293

The line-of-sight distribution of water in the SgrB2 complex

C. Comito1, P. Schilke1, M. Gerin2, T. G. Phillips3, J. Zmuidzinas3 and D. C. Lis3

1  Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, 53121 Bonn, Germany
2  Laboratoire de Radioastronomie Millimétrique, Observatoire de Paris and École Normale Supérieure, 24 rue Lhomond, 75231 Paris Cedex 05, France
3  California Institute of Technology, Downs Laboratory of Physics 320-47, Pasadena, CA 91125, USA

(Received 17 December 2002 / Accepted 27 February 2003)

We report the detection, with the Caltech Submillimeter Observatory, of the 894-GHz HDO( 11,1-00,0) transition, observed in absorption against the background continuum emission of the SgrB2 cores M and N. Radiative transfer modeling of this feature, together with the published data set of mm and submm HDO and H 218 transitions, suggests that ground-state absorption features from deuterated and non-deuterated water trace different gas components along the line of sight. In particular, while the HDO line seems to be produced by the large column densities of gas located in the SgrB2 warm envelope, the H 218 ground-state transition detected by SWAS and KAO at 548 GHz (Neufeld et al. 2000; Zmuidzinas et al. 1995a) is instead a product of the hot, diffuse, thin gas layer lying in the foreground of the SgrB2 complex.

Key words: astrochemistry -- ISM: individual objects: SgrB2 -- ISM: abundances -- ISM: molecules

Offprint request: C. Comito, ccomito@mpifr-bonn.mpg.de

SIMBAD Objects

© ESO 2003

Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.

Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.

Initial download of the metrics may take a while.