Volume 417, Number 1, April I 2004
|Page(s)||107 - 114|
|Section||Interstellar and circumstellar matter|
|Published online||16 March 2004|
Laboratoire d'Astronomie de Marseille, 2 place Le Verrier, 13248 Marseille Cedex 04, France
2 Laboratoire d'Astrophysique de l'Observatoire de Grenoble, BP 53, 38041 Grenoble Cedex 9, France
3 Observatoire de Bordeaux, 2 rue de l'Observatoire, 33270 Floirac, France
Corresponding author: D. Russeil, firstname.lastname@example.org
Accepted: 2 December 2003
We present 12CO(1–0), 12CO(2–1) and/or 13CO(1–0) observations, obtained with the 15 m SEST telescope, in the direction of 252 southern HII regions located within 2° of the galactic plane and in the interval 280. The data presented here are an important contribution to the study of the large scale structure of our Galaxy (not discussed here) as molecular information is part of the multi-wavelength study of the galactic plane. We used kinematical criteria to distinguish between lines associated with HII regions and non-associated ones. We find that HII regions are associated with molecular lines exhibiting a line-width larger than 2.5 km s-1. From a kinematical point of view we find that the velocity difference (Vco-VHII) peaks at 0 km s-1. Non-associated CO lines with the same kinematics as diffuse Hα emission (the Warm Interstellar Medium) are used to extract some statistical properties encountered in this more diffuse medium. We can determine the velocity of the three diffuse ionised gas layers detected in Hα: -3.6, -26.5 and -45.5 km .
Key words: ISM: molecules / ISM: HII regions / ISM: clouds
© 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.