EDP Sciences
Free Access
Issue
A&A
Volume 388, Number 2, June III 2002
Page(s) L44 - L47
Section Letters
DOI https://doi.org/10.1051/0004-6361:20020630
Published online 31 May 2002


A&A 388, L44-L47 (2002)
DOI: 10.1051/0004-6361:20020630

Letter

Detection of HD in emission towards Sagittarius B2

E. T. Polehampton1, 2, J.-P. Baluteau3, C. Ceccarelli4, 5, B. M. Swinyard2 and E. Caux6

1  Astrophysics, University of Oxford, Keble Road, Oxford, OX1 3RH, UK
2  Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire, OX11 0QX, UK
3  Laboratoire d'Astrophysique de Marseille, CNRS & Université de Provence, BP 8, 13376 Marseille Cedex 12, France
4  Observatoire de Bordeaux, BP 89, 33270 Floirac, France
5  Laboratoire d'Astrophysique, Observatoire de Grenoble, BP 53, 38041 Grenoble Cedex 09, France
6  CESR CNRS-UPS, BP 4346, 31028 Toulouse Cedex 04, France

(Received 4 February 2002 / Accepted 23 April 2002)

Abstract
The giant molecular cloud Sagittarius B2, located near the Galactic Centre, has been observed in the far-infrared by the ISO Long Wavelength Spectrometer. Wavelengths in the range 47-196  $\mu$m were covered with the high resolution Fabry-Pérot spectrometer, giving a spectral resolution of 30-40 km s -1. The $J=1\rightarrow0$ and $J=2\rightarrow1$ rotational transitions of HD fall within this range at 112  $\mu$m and 56  $\mu$m. A probable detection was made of the ground state $J=1\rightarrow0$ line in emission but the $J=2\rightarrow1$ line was not detected above the noise. This allowed us to calculate an upper limit on the temperature in the emitting region of approximately 80 K and a value for the deuterium abundance in the Sgr B2 envelope of $\rm D/H=(0.2{-}11)\times10^{-6}$.


Key words: ISM: abundances -- galaxy: centre -- ISM: molecules -- ISM: individual objects: Sagittarius B2

Offprint request: E. Polehampton, etp@astro.ox.ac.uk

SIMBAD Objects



© ESO 2002

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.