Please use this identifier to cite or link to this item:
http://hdl.handle.net/2289/1624
Title: | VLA detection of OH absorption from the elliptical galaxy NGC 1052 |
Authors: | Omar, A. Anantharamaiah, K.R. Rupen, M. Rigby, J. |
Keywords: | GALAXIES: ACTIVE GALAXIES: INDIVIDUAL: NGC 1052 GALAXIES: ISM RADIO LINES: GALAXIES |
Issue Date: | Jan-2002 |
Publisher: | EDP Sciences |
Citation: | Astronomy and Astrophysics, 2002, Vol.381, pL29-L32 |
Abstract: | VLA observations of OH absorption towards the elliptical galaxy NGC 1052 are presented. Both OH lines, at 1665 and 1667 MHz, were detected in absorption towards the center of NGC 1052. The hyperfine ratio of the two OH lines (tau 1667/tau 1665) is 2.6+/-0.8 as compared to 1.8 expected for the excitation under LTE conditions for an optically thin cloud. The column density of OH is estimated to be 2.73 (+/-0.26)*E14 cm-2 assuming Tex ~ 10 K. The centers of both the OH lines are redshifted from the systemic velocity of the galaxy by ~ 173 km s-1. The velocity of OH line coincides with the velocity corresponding to the strongest HI absorption. We suggest that OH absorption is arising from a molecular cloud falling towards the nucleus. The OH line, though narrower, is found to be within the much broader and smoother H2O megamaser emission. The possible link between OH/HI and H2O emission is discussed. |
URI: | http://hdl.handle.net/2289/1624 |
ISSN: | 0004-6361 |
Alternative Location: | http://arxiv.org/abs/astro-ph/0111268 http://dx.doi.org/10.1051/0004-6361:20011604 |
Copyright: | (2002) by the European Southern Observatory (ESO). |
Appears in Collections: | Research Papers (A&A) |
Files in This Item:
File | Description | Size | Format | |
---|---|---|---|---|
2002 A&A V381 L29p.pdf | 4p. | 176.72 kB | Adobe PDF | View/Open |
Items in RRI Digital Repository are protected by copyright, with all rights reserved, unless otherwise indicated.