Astronomy and Astrophysics – Astrophysics – Solar and Stellar Astrophysics
Scientific paper
2011-04-21
Astronomy and Astrophysics
Astrophysics
Solar and Stellar Astrophysics
16 pages, 4 figures, ApJL, accepted
Scientific paper
Hot subdwarf B stars (sdBs) are evolved core helium-burning stars with very thin hydrogen envelopes. In order to form an sdB, the progenitor has to lose almost all of its hydrogen envelope right at the tip of the red giant branch. In binary systems, mass transfer to the companion provides the extraordinary mass loss required for their formation. However, apparently single sdBs exist as well and their formation is unclear since decades. The merger of helium white dwarfs leading to an ignition of core helium-burning or the merger of a helium core and a low mass star during the common envelope phase have been proposed. Here we report the discovery of EC 22081-1916 as a fast rotating, single sdB star of low gravity. Its atmospheric parameters indicate, that the hydrogen envelope must be unusually thick, which is at variance with the He-WD merger scenario, but consistent with a common envelope merger of a low-mass, possibly substellar object with a red-giant core.
Classen L.
Geier Stephan
Heber Uli
No associations
LandOfFree
The fast rotating, low gravity subdwarf B star EC 22081-1916 - Remnant of a common envelope merger event 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 The fast rotating, low gravity subdwarf B star EC 22081-1916 - Remnant of a common envelope merger event, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The fast rotating, low gravity subdwarf B star EC 22081-1916 - Remnant of a common envelope merger event will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-177997