Optical spectral variability of IRAS 20508+2011 (Klochkova+, 2006)

Physics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Stars: Atmospheres, Spectroscopy, Abundances

Scientific paper

Based on high-resolution spectra we revealed variability of the optical spectrum of the cool star identified with the IR source IRAS 20508+2011. Over the five years of our observations, the radial velocity derived from photospheric absorption lines varied in the interval Vr=15-30km/s. In the same time, the H(alpha) profile varied from an intense bell-shaped emission line with a small absorption to 2-peaked emission with a central absorption feature below the continuum level. At all but one epoch, the positions of the metallic photospheric lines were systematically shifted relative to the H(alpha) emission: Delta Vr=Vr(met)-Vr(Halpha,emis)~-23km/s. The NaD doublet lines shown a complex profile with broad (half-width about 120km/s) emission and photospheric absorption, as well as an interstellar component. We used model atmospheres to determine the physical parameters and chemical composition of the star's atmosphere: Teff=4800K, logg=1.5, Vt=4.0km/s and metallicity [Fe/H]=-0.36. We detected overabundances of oxygen [O/Fe]=+1.79 (with the ratio [C/O]~-0.9), and alpha-process elements, as well as a deficit of heavy metals. The totality of the parameters suggests that the optical component of IRAS 20508+2011 is an "O-rich" AGB star with luminosity Mv~-3mag that is close to its evolution transition to the post-AGB stage.
(1 data file).

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Optical spectral variability of IRAS 20508+2011 (Klochkova+, 2006) 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 Optical spectral variability of IRAS 20508+2011 (Klochkova+, 2006), we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Optical spectral variability of IRAS 20508+2011 (Klochkova+, 2006) will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1659465

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.