6.7 GHz methanol absorption toward the Seyfert 2 galaxy NGC 3079

Free access article

Issue		A&A Volume 484, Number 3, June IV 2008


Page(s)		L43 - L46
Section		Letters
DOI		http://dx.doi.org/10.1051/0004-6361:200809985
Published online		15 May 2008

A&A 484, L43-L46 (2008)
DOI: 10.1051/0004-6361:200809985

Letter

6.7 GHz methanol absorption toward the Seyfert 2 galaxy NGC 3079

C. M. V. Impellizzeri, C. Henkel, A. L. Roy, and K. M. Menten

Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, 53121 Bonn, Germany
e-mail: violette@mpifr-bonn.mpg.de

Received 16 April 2008 / Accepted 2 May 2008

Abstract
The detection of the 6.7 GHz line of methanol (CH₃OH) is reported for the first time toward an object beyond the Magellanic Clouds. Using the Effelsberg 100 m telescope, two absorption features were identified toward the Seyfert 2 galaxy NGC 3079. Both components probably originated on lines-of-sight toward the central region, presumably absorbing the radio continuum of the nuclear sources A, B, and E of NGC 3079. One absorption feature, at the systemic velocity, is narrow and may arise from gas not related to the nuclear environment of the galaxy. The weaker blue-shifted component is wider and may trace outflowing gas. Total A-type CH₃OH column densities are estimated to be between a few times 10¹³ and a few times 10¹⁵ cm^-2. Because of a highly frequency-dependent continuum background, the overall similarity of HI, OH, and CH₃OH absorption profiles hints at molecular clouds that cover the entire area occupied by the nuclear radio continuum sources (~4 pc).

Key words: galaxies: Seyfert -- galaxies: nuclei -- galaxies: starburst -- galaxies: active -- galaxies: individual: NGC 3079 -- radio lines: galaxies

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.