EDP Sciences Journals List
Advanced Search
Subscriber Authentication Point
Home All issues Volume 403/3 Article
Free access article

Issue A&A
Volume 403, Number 3, June I 2003
Page(s) L43 - L46
Section Letters
DOI http://dx.doi.org/10.1051/0004-6361:20030577



A&A 403, L43-L46 (2003)
DOI: 10.1051/0004-6361:20030577

Letter

Widespread acetaldehyde near the Galactic Centre

J. N. Chengalur1 and N. Kanekar2

1  National Centre for Radio Astrophysics, Post Bag 3, Ganeshkhind, Pune 411 007
2  Kapteyn Institute, University of Groningen, Post Bag 800, 9700 AV Groningen

(Received 24 February 2003 / Accepted 16 April 2003)

Abstract
We present Giant Meterwave Radio Telescope images of the 1065 MHz emission from the $1_{11}\rightarrow$ 1 10 rotational transition of acetaldehyde (CH 3CHO) in the molecular cloud complex Sgr B2. Our observations are unique in that they have a high spatial resolution ( ${\sim} 4{''}$), while still being sensitive to large-scale emission. Most complex organic molecules in this cloud (e.g. acetone, methyl formate, acetic acid) are concentrated in a very small core, $\sim $0.1 pc across. In contrast, acetaldehyde is found to be spread over a region at least 100 times larger in extent. The line emission is confined to regions with radio continuum emission and correlates well (in both position and velocity) with formaldehyde absorption towards this continuum; this is consistent with earlier single dish results suggesting that it is likely to be weakly mased. Our observations also suggest that grain mantle destruction by shocks plays an important role in the observed gas phase abundance of CH 3CHO in Sgr B2.


Key words: Galaxy: centre -- ISM: clouds -- ISM: molecules -- astrochemistry -- radio lines: ISM

Offprint request: J. N. Chengalur, chengalu@ncra.tifr.res.in

SIMBAD Objects



© ESO 2003


What is OpenURL?

The OpenURL standard is a protocol for transmission of metadata describing the resource that you wish to access. An OpenURL link contains article metadata and directs it to the OpenURL server of your choice. The OpenURL server can provide access to the resource and also offer complementary services (specific search engine, export of references...). The OpenURL link can be generated by different means.
  • If your librarian has set up your subscription with an OpenURL resolver, OpenURL links appear automatically on the abstract pages.
  • You can define your own OpenURL resolver with your EDPS Account. In this case your choice will be given priority over that of your library.
  • You can use an add-on for your browser (Firefox or I.E.) to display OpenURL links on a page (see http://www.openly.com/openurlref/). You should disable this module if you wish to use the OpenURL server that you or your library have defined.