Volume 419, Number 1, May III 2004
|Page(s)||191 - 201|
|Section||Interstellar and circumstellar matter|
|Published online||23 April 2004|
The connection between W31, SGR 1806–20, and LBV 1806–20: Distance, extinction, and structure
Université Paris VII and Service d'Astrophysique, CEA Saclay, 91191 Gif-sur-Yvette Cedex, France
2 Department of Astronomy, University of Florida, 211 Bryant Space Science Center, Gainesville, FL 32611, USA e-mail: firstname.lastname@example.org
Corresponding author: S. Corbel, email@example.com
Accepted: 3 October 2003
We present new millimeter and infrared spectroscopic observations towards the radio nebula G10.0-0.3, which is powered by the wind of the Luminous Blue Variable star LBV 1806-20 also closely associated with the soft gamma-ray repeater SGR 1806-20, and believed to be located in the giant Galactic H ii complex W31. Based on observations of CO emission lines and NH3 absorption features from molecular clouds along the line of sight to G10.0-0.3, as well as the radial velocity and optical extinction of the star powering the nebula, we determine its distance to be 15.1 kpc in agreement with Corbel et al. ([CITE]). In addition, this strengthens the association of SGR 1806-20 with a massive molecular cloud at the same distance. All soft gamma-ray repeaters with precise location are now found to be associated with a site of massive star formation or molecular cloud. We also show that W31 consists of at least two distinct components along the line of sight. We suggest that G10.2-0.3 and G10.6-0.4 are located on the -30 km s-1 spiral arm at a distance from the Sun of kpc and that G10.3-0.1 may be associated with a massive molecular cloud at the same distance as the LBV star, i.e. 15.1 kpc, implying that W31 could be decomposed into two components along the line of sight.
Key words: stars: neutron / stars: individual: SGR 1806-20 / stars: individual: LBV 1806-20 / ISM: individual: W31 / Galaxy: structure / Galaxy: kinematics and dynamics
© ESO, 2004
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.