Astronomy and Astrophysics – Astrophysics – Galaxy Astrophysics
Scientific paper
2009-04-15
Astronomy and Astrophysics
Astrophysics
Galaxy Astrophysics
Accepted for publication in Astronomy and Astrophysics
Scientific paper
An isolated HI cloud with peculiar properties has recently been discovered by Dedes, Dedes, & Kalberla (2008, A&A, 491, L45) with the 300-m Arecibo telescope, and subsequently imaged with the VLA. It has an angular size of ~6', and the HI emission has a narrow line profile of width ~ 3 km/s. We explore the possibility that this cloud could be associated with a circumstellar envelope ejected by an evolved star. Observations were made in the rotational lines of CO with the IRAM-30m telescope, on three positions in the cloud, and a total-power mapping in the HI line was obtained with the Nancay Radio Telescope. CO was not detected and seems too underabundant in this cloud to be a classical late-type star circumstellar envelope. On the other hand, the HI emission is compatible with the detached-shell model that we developed for representing the external environments of AGB stars. We propose that this cloud could be a fossil circumstellar shell left over from a system that is now in a post-planetary-nebula phase. Nevertheless, we cannot rule out that it is a Galactic cloud or a member of the Local Group, although the narrow line profile would be atypical in both cases.
Bertre Th. Le
Gerard Emmanuelle
Libert Yannick
Matthews Lynn Diane
Thum Clemens
No associations
LandOfFree
CO and HI observations of an enigmatic cloud does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with CO and HI observations of an enigmatic cloud, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and CO and HI observations of an enigmatic cloud will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-591830